For people who haven't used pyro

[jp]

68532

Just a quicky comparison showing the tint of the negatives. The left negative is developed in hc110. The right negative is a pyro developed negative. (probably PMK but I'm not 100% certain; the other would be pyrocat-HD). I skip the pyro-reuse, so I get image stain and not general stain.

The brownish stain intensifies the visual look of the negative, making it appear overdone to the naked eye. However, it's tint is that of a amber safelight, so that brown stain is invisible to normal silver paper. The silver paper will receive the normal silver image without the brown stain interfering with contrast. When it's contact printed with a UV process (fill in the name of your fave alternative process), the warm tint and ultraviolet are complementary and it makes for a denser negative under those exposure conditions.

The powdered concentrate is bad for the lungs, so care should be exercised in mixing it, or you can do as I do and buy liquid concentrate. I consider it cheap compared to some of the other developer choices. The pyrocat-HD liquid concentrate for 50 liters of developer is <$30 at B&H. The concentrate is very long lasting, and you don't need much, typically 10ML from bottles A & B to do 1L of stock.

Contrast varies with agitation amount and frequency, and of course length of development. Nothing wrong with xtol/hc110/rodinal/d76, you just get additional choices and flexibility with the pyro developers, and negatives ready for both darkroom and UV printing.

[bigdog]

The brownish stain ... is that of a amber safelight, so that brown stain is invisible to normal silver paper. The silver paper will receive the normal silver image without the brown stain interfering with contrast.

If this is true, then why have so many other photographers all but insisted I convert to pyro for my roll film? :confused:

[Jay DeFehr]

68532

Just a quicky comparison showing the tint of the negatives. The left negative is developed in hc110. The right negative is a pyro developed negative. (probably PMK but I'm not 100% certain; the other would be pyrocat-HD). I skip the pyro-reuse, so I get image stain and not general stain.

The brownish stain intensifies the visual look of the negative, making it appear overdone to the naked eye. However, it's tint is that of a amber safelight, so that brown stain is invisible to normal silver paper. The silver paper will receive the normal silver image without the brown stain interfering with contrast.

I'm afraid the above is not quite accurate. First, a properly exposed and processed stained negative should look thinner to the eye than a properly exposed/processed non-stained negative, because stain is more transparent to the eye than it is to printing paper, which brings me to the second point.

Image stain is not invisible to printing paper-- graded or VC. Image stain creates print density with both types of papers, but the effect with VC papers is more complicated than with graded papers. With graded papers, image stain creates print density much like silver density does, but without the grain-- more stain = more contrast, because the stain is proportional-- more intense in the high values than in the low values.

With VC papers, the stain creates print density and acts as a low contrast filter. The consequence of these two opposing effects is that a stained negative will always print on VC paper with a split-grade-effect. The high values will print as if through a yellow filter, while the low values-- being little stained-- will print as if unfiltered, according to the light source.

If you imagine a stained, 21 step transmission scale with no general stain, with step 1 being the lowest density, and step 21 the highest, the stain will begin to be measurable at some step after #1. For the purposes of this example, let's imagine the stain is not measurable at step #3, but it is at step #4. In this case, steps 1-3 are neutral, or unfiltered, and will print on graded or VC paper identically (theoretically). Steps 4-21 will print as if yellow filtration increases with each step. In an actual negative, this is a stepless transition from non-stained, to maximum stain, in proportion to silver density, but it's not quite this simple, because the stain produces print density, increasing global contrast, but decreasing local contrast as print density increases. Step #21 is still more dense than step #20, so global contrast increases, but it prints on an effectively lower paper grade, decreasing local contrast at that step. The effect is often observed to be a preservation of highlight detail, with a flattening of local contrast. To increase contrast, we would add magenta filtration, but this may have unintended consequences.

Let's go back to the 21 step transmission scale, with measurable stain beginning on step #4. When we add magenta filtration, it adds to the yellow, creating neutral density equal to the value of magenta filtration, which makes printing times longer, and cancels the yellow filter effect up to the value of the magenta filtration. For example, if step #4 has 10 units of yellow stain, and we add 10 units of magenta filtration, we get 20 units of neutral density at step #4, and +10 units of magenta filtration at step #3. The net effect of adding 10 units of magenta filtration is to increase contrast and printing time by 10 units, but the increase in contrast is inversely proportional to the stain, being greatest where the stain is least intense, ie, in the low values, so stained negatives will always print on VC paper with a split-grade-effect, regardless of the filtration used.

I hope this helps to clarify some of the issues surrounding the printing of stained negatives.

[jp]

um. Thanks. I was trying to keep it simple. I kinda took for granted that people would understand different developers provide different tonal results. I didn't specify whether those results were optically or chemically caused. Jay credits difference to optical and has a thorough explanation.

With regard to Jay's first point, I find thinner negatives print slightly better than I imagine, and thick looking negatives don't print as hard as they look in the darkroom. I think we look at different things to judge a negative. Looks are deceiving compared to normal negatives. Regarding results from high values and low values, I see different results from PMK and Pyrocat-HD, so there's definitely chemical differences involved, and I'm not an expert on the optical differences between two pyro developers.

Bigdog, I use pyro developers for rollfilm because I want mental and process consistency with what I shoot for LF. Same reason I use the same brand and choice of film for LF and MF. I also like how highlights and shadows can be handled by pyro (which could also be obtained with skillful use of non-pyro developers if I were willing to add complexity) I don't print things monsterously enough or use a grainy enough film to judge based on grain.

[rwhb1]

I just want to say thanks for the education.

Russ

[Kimberly Anderson]

Processing 4x10's in PMK right now. I'm of the opinion that you can't over-develop in PMK.

[Robert Hall]

Nice description Jay, thanks for taking the time to do so.

R

[cdholden]

My understanding of how it works might slide into my brain a little easier if I had a step wedge. Seeing that I don't, I'm just going to develop a few more negatives and try my hand at printing them this weekend. I think seeing the results of that will be the translation to understand what was typed above.

[Jay DeFehr]

No problem, Robert. I've been trying to wrap my head around these issues for years, and the use of specialized equipment goes a long way towards sorting it all out, but I still do a lot of head scratching.

CD, getting a good print from a stained negative is not much different than getting one from a non-stained negative. Adding magenta filtration still increases contrast, but the yellow filter becomes unnecessary, as it's built in to the negative. What gets tricky is trying to understand how to adjust film exposure and development with a staining developer to get a better print on VC paper. If you follow the non-stained negative practice of increasing film development until you get normal contrast without filtration on VC paper, you're chasing a moving target, because with increased development comes increased yellow filtration. You should make peace with the fact that an optimally exposed and processed stained negative requires magenta filtration for normal contrast on VC paper. If you can accept and embrace this fact, you can avoid a lot of frustration and second-guessing in the darkroom. Good luck!

[cdholden]

It's been a long time since my last printing session. It was VC then and I didn't like it. I've got a stock of Grades 2 and 3 that I'm going to dive into this weekend. My thought is that without the "variable" part, it should be easier to nail down a decent print.

[Robert Hall]

As has been stated many times in the past, the yellow filtration offers a proportional softening of the highlights, where it is most needed, supposedly to render better highlight separation. I've not gotten in to the sensitometry of it as I simply love how a negative prints well on silver or in an alt process such as the platinotype.

Happy printing

[Jay DeFehr]

It's been a long time since my last printing session. It was VC then and I didn't like it. I've got a stock of Grades 2 and 3 that I'm going to dive into this weekend. My thought is that without the "variable" part, it should be easier to nail down a decent print.

CD, making a good print might be easier on VC paper, depending on the negative, but adjusting your film development based on feedback from printing is surely simpler when using graded papers, and I recommend this approach to those new to staining developers. A negative scaled to graded papers will also print well on VC papers (with appropriate filtration), but the reverse is not always true.

For printing on graded papers, especially grade 3 as opposed to grade 2, it can be easy to develop too much contrast into your negative. Decreasing development often results in a loss of film speed, and this is where the old adage about exposing for the shadows and developing for the highlights falls short. In order to expose for the shadows, one must know one's film's speed at a given degree of development. In any case, it's easy to see, when it happens, and simple enough to correct. If you give an extra stop (over box speed) of exposure for scenes of higher than normal contrast, it will probably compensate for the loss of film speed resulting from the decreased development required to keep highlights under control. This is why some staining developers produce more than box speed when printing on VC papers, but less when printing on graded papers. In summary, if you're printing on graded paper, you might want to give a little more exposure and a little less development than if you were printing on VC paper. Good luck!

[Ken Lee]

Is it true that in the days when people first started using Pyro for "dual-purpose" negatives (silver + UV-sensitive alt processes) only graded papers were available ?

[Jay DeFehr]

Is it true that in the days when people first started using Pyro for "dual-purpose" negatives (silver + UV-sensitive alt processes) only graded papers were available ?

Conceivably, since staining developers, UV processes and graded silver papers preceded VC papers.

[bobherbst]

No. I started using polycontrast papers in 1970. Pyro has been around as a developer for at least 130 years, probably longer.
I wrote about "dual purpose" negatives in my first View Camera article on pyro in 1997. I am sure many others already knew this property long before that article appeared.

Jay DeFehr clearly has a fine grasp of the issues and practical aspects of printing silver gelatin with pyro negatives. I will add one comment. Not all pyro negatives will look thin to the human eye. Those developed in PMK appear closer to "normal" than those developed in any pyrogallol/sodium carbonate formula. PMK (sodium metaborate) yields a green stain rather than the yellowish brown stain of the carbonate formulas. Personally, I hate looking at a green negative, but many students in my workshops brought PMK negatives and prefer it. What I learned from all of those workshops is that the density of PMK negatives "looks" closer to a non-pyro negative in terms of density than those developed in carbonate based pyro developers. At first I didn't understand why until someone pointed out to me that the human eye is more sensitive to green. Hence the negative appears denser to the human eye. Green is composed of blue and yellow. The blue component of the stain passes the UV light. It is the yellow component which blocks the UV light.

I also noticed that those students working with PMK negatives seemed to need fewer attempts to get the printing time and contrast mixture right for Pt/Pd prints compared to those students with negatives developed in carbonate-based pyro developers.


Is it true that in the days when people first started using Pyro for "dual-purpose" negatives (silver + UV-sensitive alt processes) only graded papers were available ?

[Ken Lee]

"I started using polycontrast papers in 1970."

Bob - I was referring to users of Pyro in an earlier era, like Weston in the 1920's and 30s. I guess I'm asking when Polycontrast papers were introduced.

[wclark5179]

Thanks for the info.

It's one of the nice ingredients of this site as people willingly share knowledge.

Interesting read is "The Book of Pyro" by Gordon Hutchings

I use both PMK and WD2D+

[Jay DeFehr]

Thanks for the info.

It's one of the nice ingredients of this site as people willingly share knowledge.

Interesting read is "The Book of Pyro" by Gordon Hutchings

I use both PMK and WD2D+

Hello!

I'd be interested to know why you use both PMK and WD2D+? Under what circumstances would you use one over the other?

[wclark5179]

Maybe I'm goofy, but I've read good comments on both developers. I started with WD2D+, then I bought "The Book of Pyro," reading it peaked my interest. Perhaps I should make pictures in my studio, using 2 rolls of film same brand of film ISO and batch, develop one in PMK and the other in John Wimberleys solution. Give me a week or so and I'll post some photos on the albums place.

[Jay DeFehr]

Maybe I'm goofy, but I've read good comments on both developers. I started with WD2D+, then I bought "The Book of Pyro," reading it peaked my interest. Perhaps I should make pictures in my studio, using 2 rolls of film same brand of film ISO and batch, develop one in PMK and the other in John Wimberleys solution.

Well, if you're goofy, so am I! Curiosity explains most of my choices about materials and equipment. There was a time when I had every known (to me) staining developer on my shelves, and several non-staining ones, too! It was an education. One of the things I learned is how demanding it is to meaningfully compare developers. Good luck, and enjoy!

[Cor]

Nice description on Pyro stain, Jay!

I have posted before on using PyrocatHD on IR negatives. Because it is sometimes hard to predict how much IR light there is, negatives can become quite dense, and processing in Pyro can nicely reduce contrast in these highlights. But sometimes there is just too much stain, and no filter 4 or 5 can bring contrast sufficiently back. A solution is to print on graded paper (not sensitive to Pyro stain, or perhaps not that much, I don't know)

I have also successfully removed the Pyro stain from too dense a negatives.

For non-IR film I basically stopped using PyrocatHD, in my hands it's too finicky in the development process (Jobo 2509n(?) reel and Jobo CPE2), although I now use a Expert 3010 drum on a Simma roller, and that is a big improvement, not edge density build up anymore.

Anyway in my regular Silver Gelatine work I could not see a clear superiority of PyrocatHD over XTol 1:1.

OTOH I recently started to shoot 8*10 HP5+, process in XTol instead of Pyro, and when I want to see the same negative in say platinum, I bleach and re process in Pyro,

All and all not too scientific, but fun nevertheless...;-)..

Best,

Cor

[Jay DeFehr]

Thanks, Cor. The bleach/re-develop option doesn't get mentioned often, but it's a good one, and might have some advantages over developing in a staining developer, initially. And switching to a graded paper can provide a significant boost in contrast over printing on VC paper. There are many paths to any desired end!

[bigdog]

I use pyro developers for rollfilm because I want mental and process consistency with what I shoot for LF. Same reason I use the same brand and choice of film for LF and MF. I also like how highlights and shadows can be handled by pyro (which could also be obtained with skillful use of non-pyro developers if I were willing to add complexity).

Fair enough.

I do not use sheet film. (Why I'm on this forum is up for discussion, I guess ...) ;) All of my local "photography friends" are sheet film shooters. A number of them use pyro and swear by it. One even bought me some to try, but I just haven't gotten around to it yet.

My reasoning is this: I am satisfied with what I get out of my 120 roll film and my current processes. I make the vast majority of my prints with a small amount of magenta filtration (sometimes as little as 5 on the dichro head) or no filtration at all on vc paper. The use of yellow for contrast control is rare, and with having to hit a compromise for multiple negatives on a roll of film, I like what I'm getting.

That being said, I am about to start a new project that will have a lot of highlights and potentially some high contrast subjects and I may just have to try pyro if I can't print some of what I'm shooting. This thread has increased my interest and I may "get around" to opening my gift yet.

Cheers,

PS: It's info like this that keeps me coming back here from time to time.

[ic-racer]

a split-grade-effect. .

What does that look like?

[Jay DeFehr]

What does that look like?

It looks like the low values are printed on a harder grade of paper than the high values.

[jp]

Fair enough.

That being said, I am about to start a new project that will have a lot of highlights and potentially some high contrast subjects and I may just have to try pyro if I can't print some of what I'm shooting. This thread has increased my interest and I may "get around" to opening my gift yet.


I shot a metal concert with 35mm tmy2 developed in PMK. The hard high contrast lighting (too much lights and speaker for a smaller stage) would have been impossible to tame with digital, and no fill flash was used. I didn't worry too much about the highlights because I knew the PMK would develop it fine. The final images came out great. Go shoot a roll of whatever in different high contrast situations and give your gifted developer a try.