PMK or Pyrocat HD for enlarging 4x5 negs?

[brian steinberger]

Without starting a war, I'm looking for experiences, comparisons, and or suggestions between PMK and Pyrocat HD for enlarging 4x5 negs on VC paper. I'm shooting mostly FP4 and some Tri-X and TMY. I develop my 4x5 negatives in a JOBO 3010, and have used rollo pyro so far, and the stain is VERY prominent. Not sure if I like bullet proof negs. Looking for suggestions.

What difference would I see between PMK's yellowish-green stain, and Pryocat's brown stain?

Thanks!

[steve simmons]

The color of the stain will vary somewhat depending on the film and the chemical content of the water. If you are using a JOBO the Rollo is a good choice so I would not try something new again..
Have you tried printing the negs you've already processed?

I would limit yourself to one film for awhile until you get more experience. Tri-X or Fp4+ would be my choices.

good luck


steve simmons

[Jorge Gasteazoro]

The stain for pyrocat is brownish, the one for PMK is green this is regardless of water source or film like it was erroneously posted by simmons and due to the developing agent. If you plan to enlarge my preference would be a pyrogallol developer like PMK, the best would rollo pyro since it was designed to be used on rotary machines like the Jobo.

I think the green stain is more beneficial to enlarging and VC papers than the brown stain given by Pyrocat HD.

[Jay DeFehr]

I think the best staining developer for enlarging and for rotary processing is 510-Pyro, but Rollo Pyro should be good too. The color of pyro stain v catechol stain has no impact on printing with VC papers.

Jay

[sanking]

Without starting a war, I'm looking for experiences, comparisons, and or suggestions between PMK and Pyrocat HD for enlarging 4x5 negs on VC paper. I'm shooting mostly FP4 and some Tri-X and TMY. I develop my 4x5 negatives in a JOBO 3010, and have used rollo pyro so far, and the stain is VERY prominent. Not sure if I like bullet proof negs. Looking for suggestions.

What difference would I see between PMK's yellowish-green stain, and Pryocat's brown stain?

Thanks!

Brian,

Do you mean that you are getting a lot of B+F or general stain? If it is a lot of B+F stain, something may be wrong with your materials since normally you should get fairly low B+F with Rollo Pyro in rotary processing. Also, water quality issues can sometimes result in higher general stain. Or, your film may be old and have developed some B+F, which becomes much higher with staining developers. However, Tri-X and TMY are subject to develop a fair degree of stain with rotary processing, even when the film is fresh. Then again, you may have just overexposed the negative by a stop or two.

For what it is worth I would suggest you consider Pyrocat-MC for rotary processing. It has very high acutance, good proportional stain and very low B+F, even with long development times. I have switched to it for rotary processing of all my films, though I continue to recommend Pyrocat-HD for tray processing and for the various forms of minimal agitation.

Sandy King

[Ralph Barker]

Let's keep the discussion to the technical issues and personal experience, without personal differences entering into the discussion.

[steve simmons]

If you want to know how a staining developer works there was an article in the Sept/Oct 06 issue of View Camera with Sandy King, Jay deFehr, and John Wimberly discussing just this topic. We have placed the artice in the Free Articles section of the View Camera web site. The other source I would suggest is The Book of Pyro by Gordon Hutchings which is available from Photographer's Formulary and Bostick and Sullivan.These are four of the best people around to get info about these developers.

According to Jay, Sandy and John the color of the stain is somewhat variable and depends on the staining chemical used, and the particular film, - see page 43 of the Sept/Oct 06 issue lower right hand column. In Gordon Hutchings experience, now going on 26+ years the other variables are the chemical content of the water and the agitation pattern which affects the aerial oxidation. This rings true with my experience as well which is over the same span of time.

The stain, regardless of the color has a lot of advantages, especially for printing with vc paper.

steve simmons

[brian steinberger]

Sandy,

Yes, I got alot of base+fog stain, but I also overcooked them, as you might recall from a previous post a few days earlier. Will overdevelopment add alot of b+f stain?

I havent had time to run more tests. Not til this weekend. It's dark this time of year til I get off work.

I was wondering about the benefits of Pyrocat HD, because now I'm using PMK for tank development of medium format and Rollo Pyro for 4x5 in my JOBO. I'd be nice to use one developer for all films.

Steve,

No, I haven't tried printing my negs from my first test since they were way over developed, even though amazingly the proof sheet wasn't that bad. The highlights were brought back down quit a bit by the stain. It's amazing cause the dense areas in the negs are VERY dense!

It's hard to find times for rotary processing. I'll start, as recommended by Sandy to reduce the time recommended by Gordon in the book of Pyro by 40-50%. That means from 12min w/Tri-x in Rollo Pyro (70 degrees) to 8 minutes in the JOBO 3010.

Thanks for the help!

[steve simmons]

My strong suggestion to you is to pick one developer- here I would suggest Rollo since you have some experience with it, and one film, FP4+ if you want a film speed of approx 100 or Tri-X if you need something faster. Jumping from one staining developer to another is only going to keep you confused and wondering if the next one will be better. They are all good.

If your proof sheet looked pretty good then I would stop shooting and work with that group of negs for awhile and see how they actually print. Until you've had some working experience with these negs you don;t really have a basis for making any changes or evaluating what changes you are making.

steve simmons

[Steve Wadlington]

A question, not wanting to start any arguments, about color of stain relating to scanning the film for digital darkroom. Any pro/cons on the different stain colors?

[sanking]

Sandy,

Yes, I got alot of base+fog stain, but I also overcooked them, as you might recall from a previous post a few days earlier. Will overdevelopment add alot of b+f stain?



My goodness yes. Overdevelopment should always be avoided, but overdevelopment plus overexposure with pyro staining developers is worse than the plague. The use of pyro staining developers requires good control of exposure and development or exposure times will be very, very long.


Sandy King

[sanking]

A question, not wanting to start any arguments, about color of stain relating to scanning the film for digital darkroom. Any pro/cons on the different stain colors?

Film developed in both pyrogallol and pyrocatechin based developers scan well. Most of my current printing is with digital negatives from scanned PMK and Pyrocat-HD negatives and I have been very pleased with the results from both types of negatives.

Sandy King

[Steve Wadlington]

Thanks Sandy. I have used HC-110 for years because it is so stable and long lived. I sometimes go a long time between developing. The pyrocat HD in glycol sounds like the ticket.

[Jay DeFehr]

Steve,

if you like HC110, you might consider 510-Pyro (pyrostains.blogspot.com/). 510-Pyro is a single solution, like HC110, and enjoys a similar shelf life.

Jay

[chilihead]

12 minutes for Tri X !!!! No wonder your base fog is high!!!! That is way, way ,way to long!!! What dilution are you using is also what I would ask !!! Dilution is everything (almost) with Rollo!!! After extensive work and I mean extensive- I have found Rollo is a masterful developer -capable of perfect development - 4x5, 8x10 and - 35mm!!! Perfect stain, low B/F, and absolutley CONSISTENT. Not to mention keeping qualities that are just plain marvelous... Harold Leban (inventor of Rollo) was a genius when he came up with this developer for work with the Jobo!

[Jim Noel]

I use Rollo and Pyrocat HD in addition to trying some other staining developers.

I like both Rollo and PCAt but if I intend to enlarge the negatives I prefer PCat because at similar temperatures, rotation speeds, etc I get far less base stain with it. This enables me to have shorter exposures under the enlarger.

I have not tried Pyrocat M as Sandy suggests, but will do so the next time I mix a batch.

[Jorge Gasteazoro]

The green stain does have a relevant effect on the way VC papers react or "see" the light. This has been a well known fact for many, many years. The color stain might vary slightly with the type of water used, or film, but it is not an easily seen variation or imprtant for that matter.

The main difference is the color of the stain which will give different results. I used to use graded paper and for that staining or non staining developers made no difference and in fact was pretty happy with Tmx RS.

As Sandy posted, I think your problem is not the developer but a reasonable way to figure out your correct exposure/development settings.

[Jay DeFehr]

Jorge,

my point was that pyro and catechol produce the same effect, not that there is no effect. If you're starting with a white light, and using subtractive filters (yellow=minus blue and magenta= minus green), it is simply a matter of how yellow the stain is. The result of the stain is a Yellow Filter Effect, which acts to extend the Exposure Scale of VC printing papers, and reduce print contrast. The YFE can be neutralized with magenta filtration, at which point the negative will print more or less as predicted by Blue channel densitometry. I say more or less, because the proportional nature of image stain warps the paper curve at one end or the other, or both to a lesser extent, depending on filtration. For this reason, stained negatives will never print on VC papers exactly like they print on graded papers, regardless of filtration.

Jay

[Jorge Gasteazoro]

I think you need to be more specific. Of course they can produce the same effect but the filtration would be different, therefore the color of the stain results in a different behavior for the paper. If, as you say, the color of the stain had no effect, then the filtration would be the same for both types of stain. This is an important distinction, specially if you are heading down the road of developer manufacturing, testing and experiment design.

Which reminds me, where do you get the light bands or strips they use for the sensitometers? As you know, they come with blue/green, or just blue or green. I would like to put one that is white (preferably 5500 ºK). Is this what you did with your sensitometer and where did you buy the band?

[Kirk Gittings]

May I say that I really appreciate the civility of this discussion. All of you guys have allot of knowlegde and experience to share. Even when it apears to be contradictory, it is all valid. Like Photoshop, there are numerous ways to achieve a given result, some are better for some outputs than others, some are more or less difficult to achieve, but all are successful to some degree and worth investigating.

[scott_6029]

Brian, based on your comment regarding printing, I would offer the following....You said it didn't print all that bad...stained vs. regular developed negatives can be misleading until you print. So, my advice is expose, develop and print, then make judgements....

Also, for me, I prefer less stain (shorter print times and is working great for me on azo), so I use pyro mc (tray develop) (or HD - I can't tell a whole lot of difference honestly between mc and hd, except for a little less stain with mc) - slightly longer development times - since I shuffle 6 or 8 negs at a time it would be considered minimal agitation.

I have found that overexposure is really a bad thing with pyro. I rate my films at box speed or higher....you may want to test your film speed rating. If you overexpose, it looks a lot like fog and contrast is lost. You may hear folks say, cut your box speed in half or more....well with pyro, this isn't always a good thing.....

Try rating at box speed or more, meter shadows for zone 3 and develop accordingly...to get the highlights you are envisioning.

Scott

[brian steinberger]

Thanks everyone!

Chilihead,

I'm using the standard dilution for rollo pyro (1:2:100). I would prefer to not mess with dilution until I get more experience.

Sandy,

Why, Pyrocat MC over HD? And why would you prefer less stain?

Thanks!

[sanking]

Thanks everyone!

Chilihead,

I'm using the standard dilution for rollo pyro (1:2:100). I would prefer to not mess with dilution until I get more experience.

Sandy,

Why, Pyrocat MC over HD? And why would you prefer less stain?

Thanks!

Pyrocat-MC gives slighly more acutance with rotary processing than either Pyrocat-HD or Rollo Pyro. This is the main reason I introduced the -MC variation. Rotary processing with -MC gives an edgy look, compared to a creamy look with -HD. The difference is not great.

As for stain, we don't want less proportional stain, but B+F or general stain is undesirable so that is what I want to see less of. When developing for alternative printing you need very long development times to reach the needed CI. With rotary processing, these long times tend to produce more general stain. You will get less general stain in this type of condition with -MC than -HD. Again, the difference is not great.

Sandy King

[Jay DeFehr]

I think you need to be more specific. Of course they can produce the same effect but the filtration would be different, therefore the color of the stain results in a different behavior for the paper. If, as you say, the color of the stain had no effect, then the filtration would be the same for both types of stain. This is an important distinction, specially if you are heading down the road of developer manufacturing, testing and experiment design.

Which reminds me, where do you get the light bands or strips they use for the sensitometers? As you know, they come with blue/green, or just blue or green. I would like to put one that is white (preferably 5500 ºK). Is this what you did with your sensitometer and where did you buy the band?


Hi Jorge.

When we measure the stain with the blue channel of our densitometers, we're measuring the yellowness of the stain, because yellow-minus blue. So it doesn't matter whether the stain was formed by catechol or pyrogallol, it only matters how yellow it is. In other words, a catechol stained neg that measures log 1.0 by Blue channel densitometry will produce the same print density with VC paper as a pyrogallol stained negative that measures 1.0 by blue channel densitometry, and both negatives will require the same amount of magenta filtration to neutralize. Please overlook any typos, I just returned from the optometrist, where I had my pupils dilated, and so I'm typing blind. My point is that the two agents differ only in degree. Pyro developers generally produce more stain than catechol developers do, but this is not universal.

My sensitometer uses a very bright white LED as its light source, and a Stouffer 21 step transmission scale.

Regarding stain:

Image stain is good, general stain is bad. There is no advantage to limiting image stain, except as a means of reducing general stain. Overexposure is the enemy of stained negatives, as others have rightly stated. and is proportionally more detrimental when using developers that produce significant general stain.

For those printing stained negs with VC papers, it is critical that the YFE is neutralized before assessing film development. Keep in mind that the exposing light is formed below the negative, so adding magenta filtration to neutralize the YFE doesn't contract the paper's Exposure Scale, but approximates a no-filter condition. If you don't neutralize the YFE you are essentially printing at grade 1-0, and you'll see the highlight compresion so often associated with stained negs and VC papers.

Jay

[sanking]

My take on this is that the color of the stain matters, but that the use of filtration can balance it.

I explain it this way. Start by understanding that the emulsion of VC papers consists of two different parts or coatings: a blue sensitive high contrast part or coating, and a green sensitive or low contrast part or coating. As you introduce more and more magenta into the filtration package, either by the use of higher number VC filters or by dialing in more magenta on color heads, you progressively block more and more green light. Eventually you will block almost all green light, and at that point only the high contrast blue sensitive part of the emulsion is exposed, and the VC paper will print almost exactly as a graded paper. At this point highlight compression, which results from the impact of the yellow/brown/green stain on the green sensitive part of the emulsion, is entirely eliminated. This happens with all staining developers, regardless of the exact color, but the color of the stain does determine how much magenta filtration is needed to balance the effect. If you are using a VC or MC filter set, the filter number at which most light to the green layer is blocked is about #3.5, though this will vary by filter set. Another complication is that VC papers are not all the same, i.e. their point of optimum sensitivity to both blue and green light varies.

This issue is of such fundamental importance to understanding highlight compression when printing with VC papers with stained negatives that I am almost stunned that it has not been sufficiently explained to this point in the literature. But of course, you could only fully see how this work if you test these premises with good sensitometry.

Sandy

[Eric Biggerstaff]

Hey everyone,

Thanks for a great (and civil) discussion on staining developers. I have learned a lot from this thread and I appreciate that it has maintained a polite tone despite the difference of opinion.

Please keep it up.

[Jay DeFehr]

Hi Sandy.

I've been investigating these effects using a color analyzer and a color densitometer, and you're on the right track, but still a little off. The object is to neutralize the light below the negative, so it's neither blue, nor green. Most light sources require balancing even without a negative in the carrier. Once the light source is balanced, or neutralized, placing a stained negative in the carrier introduces the Yellow Filter Effect (YFE). If that stained negative happens to be a step scale, one can place the probe of the color analyzer beneath any step of the scale and determine how much magenta filtration is required to neutralize that particular step. The only color in the negative that has any effect on the VC paper is Yellow, which is minus-blue (remember we're talking about subtractive filtration), and which creates the YFE that expands the Exposure Scale of the VC paper. Yellow+Magenta= Neutral Density, so adding magenta filtration neutralizes the YFE at the point of measurement by the analyzer probe. If the probe is placed beneath the densest step of the scale, the highlight compression is totally eliminated, and the shadow contrast is increased because the proportional image stain is practically absent in the thinnest parts of the negative, and the magenta filtration neutralized by the YFE in the highlights remains magenta in the shadows. The highlight and shadow contrasts are balanced by the placement of the neutralization point on the scale. This allows for very fine control when used intelligently. As I stated in an earlier post, and again here, the only color of stain that mattters is yellow, the color measured by Blue channel densitometry, so .1 densty from a catechol neg = .1 density from a pyro neg, both will produce the same print density with VC paper, and both will require the same amount of magenta filtration to neutralize. There is absolutely no advantage to one agent or the other regarding stain color for printing on VC papers, and I hope that particular myth will die a timely death.

Jay

[Jorge Gasteazoro]

a catechol stained neg that measures log 1.0 by Blue channel densitometry will produce the same print density with VC paper as a pyrogallol stained negative that measures 1.0 by blue channel densitometry, and both negatives will require the same amount of magenta filtration to neutralize.

I disagree with this statement because while what you say is true, it matters in what step that 1.0 density it was reached. For example you might read a 1.0 in step 11 for a green stain and you might read the same 1.0 in step 9 for a yellow stain. If we agree that paper "sees" green and blue then where it "sees" the green and blue matters.

For example you might be able to correct for the difference in the stain with filtration but that difference could mean that my enlarger might or might not have enough blue light to make up for the difference in the yellow stain.

[sanking]

The object is to neutralize the light below the negative, so it's neither blue, nor green. Most light sources require balancing even without a negative in the carrier.

Jay

Jay,

At what wavelength in nm should the light source be balanced? And why that wavelength?

Sandy King

[sanking]

If we agree that paper "sees" green and blue then where it "sees" the green and blue matters.



And it is important to remember that VC papers don't "see" equally all the way from a specific wavelength in the blue to a specific wavelength in the green. Rather, there is a specific peak in the blue, and another in the green , with a fairly large bandwith in between the two where VC papers have no sensitivity.

Sandy King

[Jay DeFehr]

I disagree with this statement because while what you say is true, it matters in what step that 1.0 density it was reached. For example you might read a 1.0 in step 11 for a green stain and you might read the same 1.0 in step 9 for a yellow stain. If we agree that paper "sees" green and blue then where it "sees" the green and blue matters.

For example you might be able to correct for the difference in the stain with filtration but that difference could mean that my enlarger might or might not have enough blue light to make up for the difference in the yellow stain.


Hi Jorge.

First, the differences in stain density betrween pyro and catechol developers are not great. My point is to correlate negative densitometry to print density and contrast. Stained negatives that match in gradient as measured by blue channel densitometry will print the same way on VC papers and require the same amount of magenta filtration to neutralize. We can forget about green because we're talking about subtractive filtration, and green doesn't enter into the equation directly. Our light source starts out more or less white and becomes more or less blue or green by subtracting one or the other. Yellow = minus Blue, Magenta = minus Green, and Yellow+Blue= Neutral Density. As a subtractive filter, the only colors that matter are Yellow and Magenta, and stained negatives produce print density by virtue of their yellowness. Let's take a real world example; a negative developed in a pyro developer to a gradient of .42 to print on the equivalent of grade 3 on VC paper. The density at step 1 measures 1.23 by blue channel densitometry. My color head requires 21 units of Magenta to neutralize the light source so that it's neither Blue nor Green on the easel, as measured by my analyzer. The negative step that measures 1.23 requires an additional 13 units of Magenta to neutralize for a total of 34 units of Magenta. So you see negatives scaled to middle grades of paper don't require excessive amounts of magenta filtration to neutralize, and are easily managed by any normal enlarger light source.

Sandy,

my analyzer doesn't display nm values because they're not really important or useful in practice. what's important is that the light source is balanced in reference to Blue and Green, or in other words, neither more Blue nor more Green, as these are the only colors to which the paper is sensitive. How the specific VC paper responds to changes in filtration is a separate subject, and I recommend Paul Butzi's article on calibrating color heads for printing VC papers as a good primer.

Jay

[sanking]

Hi Jorge.

Let's take a real world example; a negative developed in a pyro developer to a gradient of .42 to print on the equivalent of grade 3 on VC paper. The density at step 1 measures 1.23 by blue channel densitometry. My color head requires 21 units of Magenta to neutralize the light source so that it's neither Blue nor Green on the easel, as measured by my analyzer. The negative step that measures 1.23 requires an additional 13 units of Magenta to neutralize for a total of 34 units of Magenta.

Jay

And at that point, what does the curve of the step wedge print look like in the highlights? Is there shouldering, or is it a straight line? Can you show an example?

I agree that when you up the magenta to the point where the green sensitive coating of the emulsion is not exposed the print should respond rather precisely to blue channel sensitometry. But when you do that, you should lose the compensating effect in the highlights, which is one of the main reasons many people like to use staining developers with VC papers.



Sandy King

[Jay DeFehr]

Hi Sandy.

The Magenta filtration is not increased to the point that the exposing light is strictly blue, but neutral, containing both blue and green. If one wants to induce highlight shouldering, one needs only to reduce Magenta filtration, effectively placing the neutral point lower on the scale, but highlight shouldering is not always a good thing, since it reduces separation and can make the highlights appear flat. In my opinion, it is better to scale the negative to the printing paper than to rely on highlight compression to tame highlights. In my own printing, I find the increased shadow contrast resulting from neutralizing the YFE more useful than the highlight compression resulting from the YFE. In any case, knowing the materials gives the printer the option to induce highlight compression, or to avoid it.

Jay

[Jorge Gasteazoro]

First, the differences in stain density betrween pyro and catechol developers are not great. My point is to correlate negative densitometry to print density and contrast. Stained negatives that match in gradient as measured by blue channel densitometry will print the same way on VC papers and require the same amount of magenta filtration to neutralize. We can forget about green because we're talking about subtractive filtration, and green doesn't enter into the equation directly.

I disagree with this, green does enter the equation. I am afraid you are getting confused with substractive light theory. The use of a magenta filter does not mean an absence of green light. In fact the light that reaches the negative is green, it just so in the amount that was cut off by the filter.

So and emulsion that is sensitve to green will result in darker prints because a green colored negative will let more green light through than a brownish negative. In fact, if you leave the filtration settings the same and you develop the two different color negatives to the same contrast index the resulting prints will be totally different.

[sanking]

Hi Sandy.

The Magenta filtration is not increased to the point that the exposing light is strictly blue, but neutral, containing both blue and green. If one wants to induce highlight shouldering, one needs only to reduce Magenta filtration, effectively placing the neutral point lower on the scale, but highlight shouldering is not always a good thing, since it reduces separation and can make the highlights appear flat. In my opinion, it is better to scale the negative to the printing paper than to rely on highlight compression to tame highlights. In my own printing, I find the increased shadow contrast resulting from neutralizing the YFE more useful than the highlight compression resulting from the YFE. In any case, knowing the materials gives the printer the option to induce highlight compression, or to avoid it.

Jay

OK, but if eliminating highlight compensation is the point why not just use a non-staining developer?

Or, if you use a staining developer and the goal is to balance the blue and green light so as to eliminate compensation, just take a step wedge developed in a staining developer to the DR you want (as measured by blue channel sensitometry) , then contact print it with varying amounts of magenta filtration until the ES (which you can read directly by counting the steps form Dmax to paper white) matches the DR of the negative?

As I mentioned earlier, if all you want to do is eliminate highlight compression all you have to do is dial in enough magenta filtration, either by using about a #3.5 VC filter, or dialing in the required amount with a color head. At that point a stained negative printed on VC papers will pretty much match a print made with a non-stained negative on graded paper or on VC paper.

Sandy King

[Jay DeFehr]

I disagree with this, green does enter the equation. I am afraid you are getting confused with substractive light theory. The use of a magenta filter does not mean an absence of green light. In fact the light that reaches the negative is green, it just so in the amount that was cut off by the filter.

So and emulsion that is sensitve to green will result in darker prints because a green colored negative will let more green light through than a brownish negative. In fact, if you leave the filtration settings the same and you develop the two different color negatives to the same contrast index the resulting prints will be totally different.

Hi again, Jorge.

I wrote that green doesn't enter the equation directly, and it doesn't. We are talking about subtractive filtration, and Magenta does equal minus green. The light starts off as more or less white in the head, and as it passes through the filters, of which the stained negative is one, light of specific colors is subtracted, thereby changing the color balance of the exposing light. The operative color of the stained negative is Yellow, not green, and subtracts Blue to make the color balance shift towards green. By adding Magenta (minus-green) filtration, the color balance is shifted back towards Blue.

A densitometer works in the same way. The negative acts as a subtractive filter, and since Yellow = minus Blue, Blue channel densitometry measures the yellowness of the stain, so that a negative that measures X will print Y on VC paper, regardless of the agent responsible for the stain. You can test this for yourself if you have a color reflection/transmission densitometer.

Jay

[Jay DeFehr]

OK, but if eliminating highlight compensation is the point why not just use a non-staining developer?

Or, if you use a staining developer and the goal is to balance the blue and green light, just take a step wedge developed in a staining developer to the DR you want (as measured by blue channel sensitometry) , then contact print it with varying amounts of magenta filtration until the ES (which you can read directly by counting the steps form Dmax to paper white) matches the DR of the negative?.

Sandy King

Hi Sandy.

I could rephrase your question as: If highlight compression is the point, why use a staining developer with graded papers, or UV processes? The point is to know how the materials work together, and to use that knowledge to make better prints. The method you describe above is nowhere near as convenient, quick or efficient as using a color analyzer. My analyzer also doubles as a digital timer and automatically compensates for changes in aperture, filtration, enlarger height, etc.. Iterations of contact printing a stepwedge is crude to say the least.

There are many advantages offered by staining developers that have nothing to do with highlight compression, and I'd have thought you'd know that. There's no reason these benefits shouldn't transfer to VC papers without obligatory highlight compression.

Jay

[sanking]

Hi Sandy.

There are many advantages offered by staining developers that have nothing to do with highlight compression, and I'd have thought you'd know that. There's no reason these benefits shouldn't transfer to VC papers without obligatory highlight compression.

There are many advantages offered by staining developers that have nothing to do with highlight compression, and I'd have thought you'd know that.

Jay

Actually what I meant to have asked was, "OK, but if eliminating highlight compensation is the point, why not just use a non-staining tanning developer?

Tanning non-staining developers offer the same benefits to VC papes as tanning staining developers, when you eliminate the stain as a source of compensation, as I presume you know?

Sandy

[Jay DeFehr]

Actually what I meant to have asked was, "OK, but if eliminating highlight compensation is the point, why not just use a non-staining tanning developer?

Tanning non-staining developers offer the same benefits to VC papes as tanning staining developers, when you eliminate the stain as a source of compensation, as I presume you know?

Sandy

I disagree. Since image stain makes up part of the highlight density, where grain is most apparent, a staining developer reduces the appearance of grain, without reducing the appearance of sharpness by the use of a solvent developer. In short, staining developers offer all the same benefits when used with VC papers as they do when used with graded papers, with the addition of the option of introducing highlight compression.

Jay

[sanking]

I disagree. Since image stain makes up part of the highlight density, where grain is most apparent, a staining developer reduces the appearance of grain, without reducing the appearance of sharpness by the use of a solvent developer. In short, staining developers offer all the same benefits when used with VC papers as they do when used with graded papers, with the addition of the option of introducing highlight compression.

Jay

But a neutral tone stain does the same thing. It is a proportional image dye stain that also reduces the appearance of grain. By example, the dye stain in C-41 B&W films gives negatives of very fine grain.

Sandy

[Jay DeFehr]

Sandy,

I don't understand your objections. Are you suggesting that a C-41 film will produce the same image characteristics as a pyro stained neg? It seems like you're picking nits, but if you do have a point, I'm sorry I've missed it.

Jay

[sanking]

Sandy,

I don't understand your objections. Are you suggesting that a C-41 film will produce the same image characteristics as a pyro stained neg? It seems like you're picking nits, but if you do have a point, I'm sorry I've missed it.

Jay

OK, let's just leave it at that. No point in continuing an exchange where there is no communication.

[Jay DeFehr]

Sandy,

I'm doing my best to communicate, but I find your line of inquiry a little obtuse. I might be a little slow, but if you want to rephrase your question, I'll do my best to answer.

Jay

[sanking]

Sandy,

I'm doing my best to communicate, but I find your line of inquiry a little obtuse. I might be a little slow, but if you want to rephrase your question, I'll do my best to answer.

Jay

Jay,

Sorry to be so obtuse.

As for the question (s), another day perhaps.


Sandy

[Jay DeFehr]

I look forward to it, Sandy.

Jay

[John Bowen]

Jay, Sandy and Jorge,

I feel as though I'm earning my Phd in staining developers. Thanks to all of you for a great and very educational exchange.

[sanking]

Jay, Sandy and Jorge,

I feel as though I'm earning my Phd in staining developers. Thanks to all of you for a great and very educational exchange.


There was some very good information in this thread. I would just like to highlight a couple of points on which we all appear to agree.

1. Printing on Graded Papers. The stain itself does not give any highlight compensation (shouldering, compression) when printing with graded papers. You may get some compensation from the developer exhausting, as you get with some non-staining developers designed for this purpose, but you get none from the stain itself.

Importance of this fact? This is important for sensitometry because it means that if you take densitometer through a filter that is about the same in wavelength as the spectral sensitivity of graded papers you will get an accurate indicator of real printing density.

2. Printing on VC papers. There will be highlight compensation as long as the filtration allows a significant percentage of green light to reach the paper. Typically this would be the case with VC filters #3 and below, or when about equal amounts of yellow or magenta are dialed in on color enlargers, with cyan set to 0.
Highlight compensation disappears for all practical purposes with filter #3.5 and above, or with an equivalent setting on the color head of y =12, M=65. The exact numbers will vary somewhat because of slight differences in spectral sensitivity of VC papers. The same concept applies to printing with separate green and blue light sources.

Importance? This means that if you want compensation in the highlights from your staining developer you must develop your negatives to a fairly high CI (by blue channel densitometry) so that you can reduce contrast by adding yellow filtration. If you do the opposite, i.e. develop the negatives to a low CI you will have to add magenta filtration to get sufficient contrast, and you eliminate the compensation in the highlights. My own tests suggest that you need to develop to a CI of about .70 or .75 when printing on VC papers with staining developers. This is of course a much higher CI than would be needed for a #2 silver paper.


About the pyrogallol versus pyrocatechin stain color. As we know, a pyrogallol developer typically gives a yellow or yellow green , while pyrocatechin gives a brown stain. If we expose and develop two step wedges so that all 21 steps match with blue channel densitometry on the pyrogallol yellow stain and the pyrocatechin brown stain they will print the same on graded papers. This should not surprise anyone. Whatever the color, if you read the negative with a filter than matches the spectral sensitivity of the process, you will get an accurate indicator of printing density.

However, if you now print the same step wedge on VC paper, using the same filtration package for both, the brown stain negative will print with greater contrast. The stain of both negatives has the same effect on the high contrast blue sensitive part of the emulsion, but brown stain blocks more light to the low contrast green sensitive layer than yellow stain. There is no question but that you can force the two step wedges to print the same way by adjusting filtration, but they definitely will not print the same way using the same the light source with the same filtration package, unless of course that package contains so much magenta that the green sensitive layer of the VC paper is not exposed.

I recently carried out some tests to compare this very thing, using PMK and Pyrocat-HD. I used four films, two t-grain films and two traditional films, and I developed all of the samples to the same CI measured by blue channel. Then I made prints, using the same exposure time and the same filter, a #3, for all of the tests. When the step wedge prints were processed I read the densities, making final adjustments to match equivalent mid-tone densities at the same step. When I plotted the curves and compared them it was clear that in every case the negatives developed in PMK gave slightly more compensation/shouldering in the highlights than the negatives developed in Pyrocat-HD. The difference in results would have been greater had I used a #2 filter. Obviously, had I chosen to change the filtration up to a #4 or #5 the low contrast green sensitive part of the emulsion would not have been exposed, and at that point the two different negatives would have printed the same. It would also have been possible, within certain limits, to match results with the two developers, had that been a goal.

I have all this data and will eventually publish it with full notes so that others can test it for themselves if they like, but for now I can tell you for certain that the color of the stain does indeed matter when printing on VC papers, and virtually every serious printer who has ever compared results with pyrogallol and pyrocatechin type developers knows this to be the case.

Sandy King

[Kirk Gittings]

A very good sumation in terms even I can understand. Thanks.

[Jay DeFehr]

Hi again, Sandy.

We disagree on some of the points on which you feel we agree, specifically, point #2. The amount of Magenta filtration required to neutralize the YFE, and eliminate highlight compression will vary with the density of the negative. A #3.5 filter, or a filter seting of Y12 + M65 (=M53, by the way) are arbitrary, as illustrated by my example in an earlier post.


Importance? This means that if you want compensation in the highlights from your staining developer you must develop your negatives to a fairly high CI (by blue channel densitometry) so that you can reduce contrast by adding yellow filtration. If you do the opposite, i.e. develop the negatives to a low CI you will have to add magenta filtration to get sufficient contrast, and you eliminate the compensation in the highlights. My own tests suggest that you need to develop to a CI of about .70 or .75 when printing on VC papers with staining developers. This is of course a much higher CI than would be needed for a #2 silver paper.

This is not accurate. There's no need to add Yellow filtration because the stained negative is a Yellow filter. Any negative that prints normally with the light source neutralized at the easel will show highlight compression if the magenta filtration is reduced. A negative developed to a CI of .75 is scaled to a grade 0 paper, as I've said. At that point the VC paper is at or near its maximum Exposure Scale, and yellow filtration has no further effect. This degree of development is detrimental to grain and sharpness, and poison to 35mm/120 shooters.

Pyro v catechol:

Here we disagree again, and I think I know why. First of all, you're using VC filters in crude increments instead of a color head with stepless filtration, so the YFE is not precisely neutralized. Second, just because two negatives are developed to the same CI doesn't mean their curves are identically shaped, or that they will print identically. This is just as true of non-stained negatives as of stained negatives. I suggest that the highlight compression you saw with PMK has more to do with the imprecise neutralization of the YFE, and the working characteristics of that developer than the color if its stain.

With the YFE neutralized, the exposing light below the negative is neither more Green nor more Blue, and effectively prints as a graded paper would, but with a slightly steeper shoulder due to the increased shadow contrast. This bears repeating; with the YFE neutralized, the exposing light is neutral, neither more Green nor more Blue, so the color of the negative has been converted to neutral, as far as the paper is concerned. This is a very important point; the color of the negative is neutral as far as the paper is concerned. That is the heart of the issue, and if you can bend your mind to understand this, everything else follows logically.

Testing the stain colors for print density is a simple test. First, create identical densities as measured by Blue channel densitometry. A sensitometer works very precisely, but contact printing a stepwedge will do just fine. Once the steps of identical density are identified, measure them with the analyzer probe to determine how much Magenta will be required to neutralize the YFE. Since the analyzer and densitometer are calibrated, both negatives will require the same amount of magenta. With the indicated magenta filtration dialed in, print the negatives at the same time, on the same sheet of paper, and process normally. When dry, measure the reflection densities of the printed negatives. No surprise, they match as well. This is a much more conclusive test than yours because it eliminates the shapes of the curves and other non-essential charceristics as variables. You are simply not equipped to perform these kinds of tests with any degree of precision. Again, pyro stain= catechol stain regading their printing characteristics with VC papers, and I do consider myself a serious printer. The fact is that however serious other printers might be, none have taken the time to do the analysis I've done, with the appropriate equipment and experiment design, as your own methods illustrate.

Jay

[Jorge Gasteazoro]

A very good sumation in terms even I can understand. Thanks.

Agreed.....

[lee\c]

I use Pyrocat HD 2+2+100 use a Durst 138s with condensers and print on various VC papers. I use a green filter for soft and a blue filter for the hard printer. Obviously I split filter print. How does this new found info work for me?

lee\c

[Jay DeFehr]

Hi Lee.

If you've developed a system that works for you, stick with it. The problem is that it's very difficult to scale your negatives to a particular Exposure Scale, or paper grade by trial and error methods unless the YFE is neutralized. Otherwise the Exposure Scale of the paper keeps moving around with negative development, and doesn't stabilize until it's bottomed out at grade 0, which requires a needlessly dense and contrasty negative. You could eliminate the green filter from your workflow, and allow the negative itself to act as the low contrast filter. Start with a base exposure with no filter, and then find the time for the exposure with the magenta filter that gives you the best print. If your print is overexposed before it reaches optimum contrast, reduce the base exposure and start over. A few iterations should get you where you want to be. Again, the problem is in scaling your negatives. How do you curently scale your negatives?

Jay

[sanking]

Jay.

1. I have tested with both VC filters and with a BES 23-CII enlarger with a color head.

2. You may consider yourself a serious printer, and that may or may not be true. In any event, I did not say you were not a serious printer. However, your insistence that pyrogallol stain is the same as pyrocatechin stain on VC papers is just plain wrong. If step wedge negatives are developed in pyrogallol and pyrocatechin developers to the same CI, as measured by blue light densitometry, they will print identically on graded papers but they *will not* print identically on VC papers with the same filtration package, unless you increase magenta filtration to the point where all light to the low contrast green layer of the emulsion is blocked. One could adjust filtration so that at some point they print the same, but they will not print the same with the same filtration package, unless light to the green layer is blocked.

3. The shape of the curve, which you describe as one of the "non-essential characteristics" is very important. The fact that the densities match at any two or three points on the curve does not tell you the full story of toe and shoulder shape. For that, you must look at the plotted curve.

4. There is a fundamental error of concept in the way you are using the color analyzer, IMO. Balancing the color so that what you call the yellow filter effect is neutralized does not necessarily convert the color to neutral "as far as the paper is concerned" because the the analyzer does not know what color is neutral to the paper. The actual color to which the paper is neutral may be weighted heavily toward the blue, or toward the green. And analyzer only tells you what it sees, not what the paper sees.

5. The concept of the YFE may have some use, but the more important issue is the color of the exposing light. VC papers are sensitive to light that peaks at two wavelengths, one the green, another in the blue. Many people expose VC papers with two light systems, one blue and one green, and match contrast to the number of units of exposure of each that are applied to the paper. Try printing the step wedge negatives developed in pyrogallol and pyrocatechin developers to the same CI using the same units of blue and green light and see what happens.

Sandy King

[brian steinberger]

So, if I run tests to determine personal film speed test, and development time using a staining developer, say I get my personal EI (assuming .1 above fb+f) now want to test for development time. I shoot a few zone VIII exposures and enlarge the negatives to lightest tone visable on paper, what grade do I use? And how does the stain not affect the results of the Zone VIII test?

If you read a zone VIII density though a densitometer to eliminate the yellow stain and come up with an appropiate density for VC paper (1.29) but then go to print with this density, due to the stain wouldn't the results would come up short (due to highlight compression)?

Sorry if I'm confusing. Do you understand what I'm trying to ask?

[sanking]

Hi Lee.

You could eliminate the green filter from your workflow, and allow the negative itself to act as the low contrast filter.

Jay

How much potential contrast control would you have using only the stain in the negative. For example, in an example you gave earlier where step 1 measures 1.23 by blue channel densitometry, how much of that density is stain? Probably not much more than .20, right?

By contrast, a #1 yellow filter blocks more than twice that amount, easily over log .040. It would seem to me that one would have a lot more potential control with the filter than the stain in the negative.

But I don't use the kind of split color printing so perhaps I am missing an important point here.

Sandy King

[Jorge Gasteazoro]

If step wedge negatives are developed in pyrogallol and pyrocatechin developers to the same CI, as measured by blue light densitometry, they will print identically on graded papers but they *will not* print identically on VC papers with the same filtration package, unless you increase magenta filtration to the point where all light to the low contrast green layer of the emulsion is blocked.

Everybody that has tested these developers and done this with VC papers knows this. To keep arguing about this is an exercise in futility. Jay is never going to be convinced and there is no argument that we can present that will do so.

[sanking]

Everybody that has tested these developers and done this with VC papers knows this. To keep arguing about this is an exercise in futility. Jay is never going to be convinced and there is no argument that we can present that will do so.

Well, I am going to bow out of the thread at this point. As I indicate, I have complete data to support my own conclusions, and will eventually publish the data, after it has reviewed by the two persons who agreed to work with me on the pyro project. So eventually everyone can look at the results and test for themselves to verify or repudiate the methodology and conclusions.

I assume Jay will also try to publish his data and conclusions. However, I would recommend that he have it reviewed by someone else who understands the sensitometry of pyro developers before doing so.

Sandy

[Jay DeFehr]

Hi Sandy.


I guess when you wrote:

[QUOTE]I can tell you for certain that the color of the stain does indeed matter when printing on VC papers, and virtually every serious printer who has ever compared results with pyrogallol and pyrocatechin type developers knows this to be the case.

I took it to mean that you don't consider me a serious printer, since I absolutely disagree with you on this subject.


1. I have tested with both VC filters and with a BES 23-CII enlarger with a color head.

Perhaps you could explain why you chose to use Yellow + Magenta filtration for your tests with the color head? The bottom line is that without a color analyzer, you can't accurately neutralize the YFE.



If step wedge negatives are developed in pyrogallol and pyrocatechin developers to the same CI, as measured by blue light densitometry, they will print identically on graded papers but they *will not* print identically on VC papers, unless you increase magenta filtration to the point where all light to the low contrast green layer of the emulsion is blocked. One could adjust filtration so that at some point they print the same, but they will not print the same with the same filtration package, unless light to the green layer is blocked.

Sorry, but this is not true. Negative density X will print density Y on VC paper regardless of the agent responsible for the stain when the YFE is neutralized. there is no need to develop to a specifc CI to test the neg density v printing density, and it introduces all kinds of variables that have nothing to do with the experiment.


3. The shape of the curve, which you describe as one of the "non-essential characteristics" is very important. The fact that the densities match at any two or three points on the curve does not tell you the full story of toe and shoulder shape. For that, you must look at the plotted curve.

You've misunderstood me. The shape of the curve is most certainly non-essential when the object of the experiment is to determine whether matching densities as determined by blue channel densitometry produce matching print densities with VC papers using the same filtration. Remember, we're debating the effect of the color of the stain on VC papers, not the working properties of the developers.



4. There is a fundamental error of concept in the way you are using the color analyzer, IMO. Balancing the color so that what you call the yellow filter effect is neutralized does not necessarily convert the color to neutral "as far as the paper is concerned" because the the analyzer does not know what color is neutral to the paper. The actual color to which the paper is neutral may be weighted heavily toward the blue, or toward the green. And analyzer only tells you what it sees, not what the paper sees.

There's no error of concept. As I stated in an earlier post, most light sources require neutralization even without a negative in the carrier. This is a simple calibration procedure. With the light source neutralized according to the analyzer, neither more green, nor more blue, a stepwedge is printed on the VC paper in question, and the Exposure Scale of the paper determined by reflection densitometry. When the Exposure Scale measures in the grade 2 range, it indicates a neutral light source. You're making this more complicated than it needs to be.


5. The concept of the YFE may have some use, but the more important issue is the color of the exposing light. VC papers are sensitive to light that peaks at two wavelengths, one the green, another in the blue. Many people expose VC papers with two light systems, one blue and one green, and match contrast to the number of units of exposure of each that are applied to the paper. Try printing the step wedge negatives developed in pyrogallol and pyrocatechin developers to the same CI using the same units of blue and green light and see what happens.




I've covered these issues already, but will repeat myself here; the color of the exposing light is neutral, as determined by the calibration procedure noted above. It comes as no surprise to me that neutral to the color analyzer is also neutral to the VC paper, and once the YFE is neutralized, the exposing light is neutral, and the color of the negative is neutralized, pyro and catechol negs print identically. To test the effect of the color of the stain on VC papers, it is just common sense to isolate the color as a variable, and introducing non-essential characteristics into the experiment invalidates the results. These are practical, hands-on results, and not theory dependant on undefined peak spectral sensitivities. I've done the work, and I'm confident in my results. This information has never been presented, and is of great value to those printing stained negatives with VC papers, despite your unfounded objections. In my opinion you're doing a disservice to users of staining developers by trying to obfuscate the concepts involved.

Jay

[Jay DeFehr]

Everybody that has tested these developers and done this with VC papers knows this. To keep arguing about this is an exercise in futility. Jay is never going to be convinced and there is no argument that we can present that will do so.

Hi Jorge.

Sandy has commented many times that an in-depth investigation of the effects of stained negatives with VC papers has not been done. I've done the work, so I won't be persuaded by erroneous information based on flawed experimental design, no matter how long it's been propogated, or by whom. I've pointed out the flaws in Sandy's methodology that explain his flawed results, if you'd like to post your testing methodology, I'd be happy to analyse it for errors as well. The goal is good information, not maintanence of the staus quo.


So, if I run tests to determine personal film speed test, and development time using a staining developer, say I get my personal EI (assuming .1 above fb+f) now want to test for development time. I shoot a few zone VIII exposures and enlarge the negatives to lightest tone visable on paper, what grade do I use? And how does the stain not affect the results of the Zone VIII test? If you read a zone VIII density though a densitometer to eliminate the yellow stain and come up with an appropiate density for VC paper (1.29) but then go to print with this density, due to the stain wouldn't the results would come up short (due to highlight compression)?


Hi Brian.

you've identified the problems very well, and they are some of the reasons printing stained negatives on VC papers have been so frustrating for so many. Due to the YFE, your paper's Exposure Scale moves around with negative development, so trying to calibrate your system is like trying to hit a moving target. To get useful exposure and development information from your tests, your paper's ES must be constant, and the only way to do that is to neutralize the YFE with magenta filtration. To do so precisely requires the use of a color analyzer/timer. If you don't have an analyzer/timer, I recommend doing your calibrations with graded paper. Once your calibration procedure is complete, it can be transferred to VC paper by matching the graded paper's Exposure Scale by adding magenta filtration. Once this is done, you can increase or decrease print contrast by increasing or deceasing magenta filtration to fine tune your prints. It might seem like an unnecessary complication to use a graded paper for calibration when you intend to print on VC paper, but if you don't have a color analyzer/timer, it will save you much frustration and wasted time and material trying to hit that moving target. I hope this makes some sense, but if it doesn't let me know and I'll try to clarify.

Jay

[Jorge Gasteazoro]

I'd be happy to analyse it for errors as well.

This assumes you know what you are doing and have experience in experiment design. So far, the arguments you have presented only tells me you dont understand color theory and filtration and your basic premise that the stain does not matter is flawed. We have tried to show you where you are wrong but you wont listen in your unshakeable beleif that you alone are right.

In a nut shell, two different color negatives project two diffrent light spectra on the paper, VC paper reacts differently to these two kinds of spectra even if you dont want to beleive it.

I am sorry Jay, but I doubt there is anything you can teach me about experiment design, so I will decline your offer to check my work for errors, better and more prepared people than you have done this.

[Jorge Gasteazoro]

Well, I am going to bow out of the thread at this point. As I indicate, I have complete data to support my own conclusions, and will eventually publish the data, after it has reviewed by the two persons who agreed to work with me on the pyro project. So eventually everyone can look at the results and test for themselves to verify or repudiate the methodology and conclusions.

I assume Jay will also try to publish his data and conclusions. However, I would recommend that he have it reviewed by someone else who understands the sensitometry of pyro developers before doing so.

Sandy

I am done with this too, the sensitometry here is very basic, and to keep arguing in circles is pointless. When someone cannot understand or wont acknowledge a very simple fact then communication is impossible. Bottom line, I have not seen any evidence, not has anybody presented any evindence that stain color does not matter with VC papers, but I have seen enough data and preform enough experiments myself to know that it does. This is all I need to know, so I guess I am putting this thread in the ignore section.

[sanking]

I've covered these issues already, but will repeat myself here; the color of the exposing light is neutral, as determined by the calibration procedure noted above. It comes as no surprise to me that neutral to the color analyzer is also neutral to the VC paper, and once the YFE is neutralized, the exposing light is neutral, and the color of the negative is neutralized, pyro and catechol negs print identically. To test the effect of the color of the stain on VC papers, it is just common sense to isolate the color as a variable, and introducing non-essential characteristics into the experiment invalidates the results. These are practical, hands-on results, and not theory dependant on undefined peak spectral sensitivities. I've done the work, and I'm confident in my results. This information has never been presented, and is of great value to those printing stained negatives with VC papers, despite your unfounded objections. In my opinion you're doing a disservice to users of staining developers by trying to obfuscate the concepts involved.

Jay

I promised to bow out of this thread but not just yet.

It strikes me that it is about time for Brian Ellis to drop by and ask, "Anyone for D-76." And in this case it would be highly appropriate.

You point out that with your system, if the "color of the negative is neutralized, pyro and catechol negs print identically." Well, yes, they do, but they also print identically to a negative developed in a non-staining developer developed to the same CI. And all three negative willl then print the same way on graded papers.

Now, did everybody get that? By neutralizing the stain you are depending for system accuracy in exposure on the fact that you have essentially thrown out of the system what many consider the most important characteristic of staining developers when printed on VC papers, i.e. the ability to control extreme highlight detail with compensation. This, after all, is at the heart of Gordon Hutchins' promotion of the staining developer PMK in The Book of Pyro.

It is a waste of time to design a system that allows you to print with a staining developer so that it gives the same results as if printing with a traditional negative. In this case IMO you might as as well use a non-staining developer, or a developer that tans but does not stain. Or a B&W C-41 if available in your format. You will get similar results without all the intellectual masturbation.

I would very much like to see a good study on the use of staining developers with VC papers. It appears to me that your study does not cut the mustard, for the reasons already given.

Sandy King

[Jay DeFehr]

Hi Sandy.

I'm glad you haven't abandoned this discussion because it gives me a chance to clear up the misconceptions you've raised.


You point out that with your system, if the "color of the negative is neutralized, pyro and catechol negs print identically." Well, yes, they do, but they also print identically to a negative developed in a non-staining developer developed to the same CI. And all three negative willl then print the same way on graded papers.

You're still having trouble with the basic concepts. No, stained negatives won't print on VC papers exactly like non-stained negatives, or stained negatives printed on graded papers, even when the YFE is neutralized, because of the proportional nature of image stain. When the YFE is neutralized at the point of highest density, the light is still magenta in the shadow areas of the negative, where there is little stain. The result is an increase in the shoulder of the paper curve, which indicates increased shadow contrast in the print. Now, did you get that?


By neutralizing the stain you are depending for system accuracy in exposure on the fact that you have essentially thrown out of the system what many consider the most important characteristic of staining developers when printed on VC papers, i.e. the ability to control extreme highlight detail with compensation. This, after all, is at the heart of Gordon Hutchins' promotion of the staining developer PMK in The Book of Pyro.


First, there can be no system accuracy if the paper's Exposure Scale changes with film development, and the only way to fix the exposure scale of the paper is to neutralize the YFE. Once that is done, the printer is free to re-introduce the YFE for highlight compression, if so desired. The idea that highlight compression is the cheif advantage of a staining developer is pure nonsense, and would argue against the use of staining developers with graded papers or UV processes. That being said, a printer who understands his materials would have no trouble utilizing that particular control when it's an advantage to do so, and wouldn't need to develop his film to a ludicrous CI of .75 to make it work.


It is a waste of time to design a system that allows you to print with a staining developer so that it gives the same results as if printing with a traditional negative. In this case IMO you might as as well use a non-staining developer, or a developer that tans but does not stain. Or a B&W C-41 if available in your format. You will get similar results without all the intellectual masturbation.

Okay Sandy, apparently a lesson in the advantages of staining developers is in order.

1) Proportional image stain.

Proportional image stain means that the stain is formed in proportion to the silver density, and is greatest in the regions of highest silver density, or the highlights, where grain is most apparent. This means that less silver density is required to produce a given print density, which in turn means that since image stain is grainless, there is less grain for a given print density. This advantage applies equally to graded papers, and VC papers, unless the negative to be printed on VC paper is developed to an extreme CI to print without filtration.

2) Emulsion tanning:

Pyro and to a lesser degree, catechol, tan photographic gelatin. The tanning action hardens the emulsion in proportion to the exposure, so that regions of high exposure harden, restricting access to the emusion by the developer, and thereby encouraging the formation of adjacency effects. Certain staining/tanning developers also exhibit a compensating effect as the developer exhausts in the highlight regions, due in part to the hardening of the emulsion there. These benefits also apply equally to graded and VC papers, but these enhanced acutance effects rely on the thinnest negatives consistent with adequate shadow detail, and are significantly reduced, or eliminated when the negative is overexposed and/or overdeveloped.

There are other advantages that apply specifically to UV processes, and are irrelevant to this discussion.

If you sincerely believe that a non-staining developer, or C-41 film will produce the same image characteristics as a staining/tanning developer, you've got a lot of homework to do, and your opinion carries no weight. The fact is that the system I've described allows the printer to target his negatives to a specific Exposure Scale of his choice, and to fine tune the degree of highlight compression/shadow contrast to suit his personal vision. The alternative you favor is no sytem at all, and leaves the printer to either accept highlight compression, or print on grade 00 paper. Now I leave you to your masturbation.

Jay

[brian steinberger]

Jay,

I should use graded paper for the zone VIII tests? This makes sense. But what if the graded paper's exposure scale isn't the same as the VC variety? What kind of analyzer are you using? Are they reasonably priced used?

[sanking]

Hi Sandy.

(many snips)

I'm glad you haven't abandoned this discussion because it gives me a chance to clear up the misconceptions you've raised.

Now, did you get that?

Okay Sandy, apparently a lesson in the advantages of staining developers is in order.

you've got a lot of homework to do, and your opinion carries no weight.

Now I leave you to your masturbation.

Jay



Jay,

I had expected that we could discuss the issues without resort to snide remarks and personal insults.

Too bad.

Sandy

[ajduran]

I don't want a highlight compensating effect from a tanning/staining developer. I use a tanning/staining developer because:

A. Tanning developers such as pyro and catechol give excellent sharpness.
B. Image stain is reputed to reduce the appearance of grain, especially in highlight areas such as the sky, where it would be most noticeable.

Sandy, from what you are saying, if I don't want any highlight compensating effect on VC papers then I should reduce development to the point that my negatives require approximately grade 3.5 filtration. In this case, do you still feel there is any real benefit to a tanning/staining developer with VC papers or would one be just as well to use a slightly finer grained but fairly sharp non staining developer? Most of what I have read indicates that when pyro/catechol developers are formulated to give no stain the grain is fairly significant. Whether or not this would make a difference with an 8x10 or 16x20 from a 4x5 negative is a different issue but grain is something I don't much care for.

Andy

[Jay DeFehr]

Hi Brian.

The beauty of VC papers is that their Exposure Scales are variable, and adjustable by the use of contrast filtration. Once your calibrations are completed on graded paper, all you need to do is match the exposure scale of the VC paper to the ES of the graded paper. You can do this precisely by contact printing a stepwedge, but practically speaking, all you have to do is adjust the magenta filtration to get the best print, which will reflect your calibration.

Color analyzers are very inexpensive used, because color printers have gone digital in droves, and have flooded the market with their used equipment. I use a Jobo ColorStar analyzer/digital timer, and recommend it highly. I strongly suggest you look for one that is both an analyzer and timer, and will compensate automatically for changes in aperture, filtration, enlarger height, etc.. A color head combined with this kind of analyzer represents the best system currently available for printing stained negatives on VC papers. I've been speaking with some manufacturers about producing a VC head that works on the principles I've described, and hopefully they will determine that the market warrants the expense of developing the system, but I think it's a coin toss at this point. Good luck, and let me know if I can be of any help.

Jay

[Jay DeFehr]

The idea that printers prize staining developers for the highlight compression they produce when uncorrected for VC paper is a myth, in my opinion. In my experience, most printers express frustration with staining developers for printing with VC papers because they have trouble calibrating their systems, and get flat prints unless they significantly overdevelop their negatives. I've addressed these problems and described a system that gives the printer complete control over his materials.

Sandy,

I don't want to play your victim game, so I won't go back and snip all of your snide comments. If your ego is bruised, that's your problem, not mine.

Jay

[sanking]

I
Sandy, from what you are saying, if I don't want any highlight compensating effect on VC papers then I should reduce development to the point that my negatives require approximately grade 3.5 filtration. In this case, do you still feel there is any real benefit to a tanning/staining developer with VC papers or would one be just as well to use a slightly finer grained but fairly sharp non staining developer? Most of what I have read indicates that when pyro/catechol developers are formulated to give no stain the grain is fairly significant. Whether or not this would make a difference with an 8x10 or 16x20 from a 4x5 negative is a different issue but grain is something I don't much care for.

Andy


If highlight compensation with VC papers is not important for you, and grain size is, I would recommend that you switch to a non-staining developer, especially for 35mm and roll film for printing on VC papers. For this purpose Xtol gives finer grain than any of the pyrogallol or pyrocatechin based developers.

Sandy King

[Jay DeFehr]

Sandy,

while I appreciate your recommendation, I choose a developer based on total imaging characteristics, and not just one specific characteristic. On the other hand, if I want to utilize highlight compression with VC paprs, I know exactly how to do it. If highlight compression is important to you, I recommend you avoid graded papers and UV processes, or choose a developer that allows for compensation with those materials. Hypercat is very good in that regard, much better than Pyrocats.

Jay

[sanking]

Sandy,

while I appreciate your recommendation, I choose a developer based on total imaging characteristics, and not just one specific characteristic. On the other hand, if I want to utilize highlight compression with VC paprs, I know exactly how to do it. If highlight compression is important to you, I recommend you avoid graded papers and UV processes, or choose a developer that allows for compensation with those materials. Hypercat is very good in that regard, much better than Pyrocats.

Jay


Thanks for your recommendation.

However, having never seen any of your work (and don't know anyone else who has), either in the print media or on exhibition in a public forum, your recommendation about print quality and your reasons for choosing a developer does not carry a lot of weight with me.

Let me know when your work can be viewed outside of Boise. I woudl love to see it.

Sandy

[Jay DeFehr]

Sandy,

do you have a problem with Boise? Do you think my prints would look different outside of our city limits? I'm perfectly content to show my prints to anyone who wants to see them, and I'm intelligent enough to understand that a lot of low quality work is exhibited and printed all over the world, so don't confuse exhibition with quality. If youre ever in Boise and want to see some prints, just let me know, I'd be happy to oblige. In the meantime, you might consider learning to interpret film curves, they can tell you a lot about a film/developer combination without needing to see a print. Once you get the hang of it, you can spot compensation in a film curve at a glance.

Now, if you're finished with your childishness, maybe you could describe your procedure for calibrating a staining developer/VC paper system? I'm very curious to know how you manage these issues.

Jay

[ajduran]

If highlight compensation with VC papers is not important for you, and grain size is, I would recommend that you switch to a non-staining developer, especially for 35mm and roll film. Xtol gives finer grain than any of the pyrogallol or pyrocatechin based developers.

Sandy King

Thanks for your reply Sandy

Andy

[sanking]

[QUOTE=Jay De Fehr;207028]Sandy,

do you have a problem with Boise? Do you think my prints would look different outside of our city limits? Jay[/QUOTE


I have no idea what your prints look like.

However, if you seek credibility for your opinions about print quality you need to establish it through showing your own work, perhaps starting in Boise, and then on a national and international level, and in print publications if possible.

You won't get any free passes on this. No one does. One has to establish credibility with real prints, shown in print media and in exhibition.

Sandy King

[sanking]

Sandy?........

That's about what I expected. I hope you'll post your method for the benefit of all of us who print stained negatives with VC papers.

Jay

I already posted the method earlier in this thread. Develop to a fairly high CI (about .65 - .75), as measured by blue channel sensitomery and use yellow or magenta filtration to control contrast. And be reminded that if you go higher than a VC #3.5 ( or the equivalent in using a color head), there will be no highlight compensation because of the blocking of green light to the emulsion of the paper.

My premise is that for VC silver papers highlight compensation is desired. If it is not, I would suggest switching to an non-staining developer like Xtol, especially for 35mm and medium format work.

Is that clear enough for you?

Sandy King