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Bill_1856
10-Aug-2011, 13:59
In addition to the staining effect, does developing in Pyro give a broader effective sensitivity to thick emulson films (such as Adox CHS or Arista.EDU Ultra) than standard developers such as D76, Rodinal, or Xtol?
I am anticipating using the film in an ancient camera with a single shutter speed, and Gawd knows what it is, probably around 1/25 or 1/50. I want as much wiggle room with the exposure as possible.
At least the aperture is marked F:9/11/16 which is probably ASA not the old US designation.
Diafine is not an option as for once I don't need/want the extra speed, and I've never had any luck with stand development.

jp
10-Aug-2011, 14:07
For maximum wiggle room, some ND filters might get you the exposure you're after.

I think there are film exposure limitations that are not resolved by magic bullet developer. I think it kinda depends on the subject matter and how fussy you are about dense highlights and how you can deal with contrast by VC printing or scanning. If you overexpose the shadows and there aren't much for highlights, printing it shouldn't be a problem for example. I think with PMK you can overexpose the highlights a bit more than d76/xtol as it will compress them a little.

onnect17
10-Aug-2011, 15:24
In addition to the staining effect, does developing in Pyro give a broader effective sensitivity to thick emulson films (such as Adox CHS or Arista.EDU Ultra) than standard developers such as D76, Rodinal, or Xtol?
I am anticipating using the film in an ancient camera with a single shutter speed, and Gawd knows what it is, probably around 1/25 or 1/50. I want as much wiggle room with the exposure as possible.
At least the aperture is marked F:9/11/16 which is probably ASA not the old US designation.
Diafine is not an option as for once I don't need/want the extra speed, and I've never had any luck with stand development.

Bill, you should visit pyrocat-hd.com for links
IMHO, its the staining the one doing the magic. Also, check with Sandy for details.
Here's a shot developed in pyrocat-hd using a small tank. I was in Myakka State Park two weeks ago.

Jay DeFehr
10-Aug-2011, 17:09
Hi Bill,

I too have a few old cameras with just one shutter speed and aperture. I usually figure these things were made to use Verichrome, or similar, on sunny days, outdoors. I also figure if the shutter isn't accurate, it's probably slow. Your camera might not relate to any of my assumptions, but I tend to use ISO 100 films in these things. Incidentally, none of the films you mention are thick emulsion films. I don't know if we can still buy thick emulsion film, unless it's X-Ray film. When I need a developer I'm sure won't let me down, I use 510-Pyro. I use it up here in Alaska shooting an old Kodak 2A, and developing in a tin can without a thermometer, graduate, timer, or film reel, and it never lets me down. I put one or two ml of 510-Pyro in about a 1/2 liter of water with my roll of film curled up in the bottom and agitate for about a minute, then take a shower. After my shower, I agitate for about another minute, then get dressed. After I'm dressed I pour out the developer and fix/wash, etc. I always get printable negatives. Why is 510-Pyro so reliable? I suspect there is no single reason, but a combination of factors. 510-Pyro has enormous developing capacity. One photographer used a 1:1000 dilution to develop 11x14 sheet film with good results, though very long developing times. So, if there's any concentrate in your developer, it will probably develop your film, given enough time. It also has excellent keeping properties. I've found old, partial bottles of concentrate of unknown origin, black as used motor oil that worked perfectly fine. It doesn't seem to be very sensitive to contamination, because it has never just outright failed the way catechol developers can. Then there's all the stuff we know about staining and tanning that make these kinds of developers so useful. Taken in aggregate, 510-Pyro is just extremely robust and simple to use. There's almost no way to abuse it. You can use it for any film format, because it produces very fine grain and excellent sharpness, and you can use any method of development you like, from trays, to tanks, to tubes, to ziplock bags, from semi-stand to rotary, and everything in-between. The only circumstance in which I would avoid it is when developing old, fogged film. The pyro will stain the fog just like it does the image silver, and exacerbate the condition.

Good luck, and have fun with your old camera. I love finding an old camera on a shelf or in a bin, putting some film in it, and making photos. I need to pass some of my old cameras along to make room for new old cameras.:D

Bill_1856
10-Aug-2011, 17:34
Thanks Jay. I'm so out of date that I never even heard of 510-Pyro. Guess that I'll have to find the newest edition of Anchell's handy dandy developing guide (mine is the 2nd edition, briefly mentioning Pyro).
Incidentally, I didn't know that people in Alaska showered. My u-no-what shrivels up just imagining it!

Armando, Myakka Park is my Point Lobos -- I'm out there at least once nearly every week.

Jay DeFehr
10-Aug-2011, 17:44
Bill,

I don't think you're out of date; most people have never heard of 510-Pyro, but it is in the latest Darkroom Cookbook. As for showering in Alaska, when it's -40F, a hot shower feels pretty good!

Greg Blank
10-Aug-2011, 17:59
Pyro does not increase the sensitivity, as a matter of fact few if any developers do that.

Sensistivity is measured at the toe of film which is the shadow area where exposure first occurs. Developer differences are apparent only in control the mid tones and the highlights- imop. If you typically have a wide range of values in a scene then a Pyro negative "can" contain more higher values in a printable area relative to a printing paper than say the same scene exposed and developed in say straight D76. But even that will vary depending on how the chemistry is used. In other words if you study the use of any developer you can get excellent results. For instance: I have used PMK for years, but have been recently using HC110 F dilution.

mikebarger
10-Aug-2011, 18:37
+1 for 510 Pyro, excellent developer and I have abused it. ;)

onnect17
10-Aug-2011, 19:14
Bill, I use both, pyrocat-hd and 510-pyro with similar results IMO. Any will be good to start.
If using a Jobo go for speed. Avoid the motor base, too slow. If using small tanks, one inversion every 15 secs will do.
I'm not a fan of stand development neither.

Robert Ley
10-Aug-2011, 20:56
Armondo, I had always assumed that in the instruction for the Jobo Expert film Drums, a slower rotation speed was to be used. I have always used a slower speed on my CPA-2 and it has worked well.

Jay, I have bought the 510 pyro from you and frankly have never tried it. After this thread I am going to definitely give it a try as I am running some tests on several new films (new to me). I need ball park development times for HP-5+, TMAX 400 (new)
Arista EDU Ultra 200, and Arista EDU 200 and 400 (I think that this is Fortepan) I use a Jobo Expert as above.

Jay DeFehr
10-Aug-2011, 21:58
Hi Robert,

If you bought 510-Pyro from me, it must be well aged by now! I'm sure it's fine. For ballpark times, 510-Pyro 1:100 = times for D-76 stock. Good luck, and let me know if I can help.

onnect17
11-Aug-2011, 07:34
Robert, It's my believe the level of agitation is a function of the linear speed (linked to rotational speed + diameter of the tank), tank/reel design (flaps, etc.) and unused tank space. An expert tank in the CPP could agitate more than a 2500 in a CPE.
The used developer should be quite dark with enough agitation.

Jim Noel
11-Aug-2011, 08:12
My old standby for such problems is Divided D-23 by inspection.

Jay DeFehr
11-Aug-2011, 08:16
Armando,

I have a different view of agitation. I see a spectrum of effective agitation with just enough to avoid bromide streaks, mottling, etc. on one end, and on the other end, the point beyond which increased agitation no longer results in increased contrast. In my testing I've found no difference in contrast between the most gentle continuous agitation, and the most vigorous. All that excess vigor produces foam, oxidation, and the occasional leak, or dislodged film, but little else. Continuous agitation, however gentle, is well beyond danger of bromide streaks and mottling and other effects of under-agitation. I see no advantage to fast rotating/vigorous continuous agitation.

onnect17
12-Aug-2011, 09:23
Jay, If I remember correctly I was not happy with some results when I used the slow speed in the jobo. I will test both developers later with different levels of agitation and compare the results. Thanks again for your input and, of course, I will post the results.

sanking
12-Aug-2011, 14:18
Jay, If I remember correctly I was not happy with some results when I used the slow speed in the jobo. I will test both developers later with different levels of agitation and compare the results. Thanks again for your input and, of course, I will post the results.

Look forward to your results. My experience is pretty much in accord with the opinion offered by Jay, i.e. beyond the point needed to achieve even development there is nothing achieved with faster/more vigorous agitation, except for the fact that there will be more contrast with more vigorous agitation than with slow agitation.

However, my instinct tells me that your results may be highly dependent on the exact developer and the amount of solution used per given film area, and if a staining developer, on the type and amount of anti-oxidizing agent, and on whether or not high stain is or is not important.

Sandy

nolindan
13-Aug-2011, 09:22
You may want to use a very wide latitude film, like TMAX, and develop it in a developer that gives a very straight line characteristic like D-76.

Plan on overexposure, such that your worst lit subject will be correctly exposed. Do not overdevelop - err on the underdevelopment side.

Your well lit scenes will produce very dense negatives but they will be printable.

Pyro developers tend to produce a marked shoulder - this can make highlights easier to print as they don't need burning in to preserve detail. However if you overexpose you will get rather a flat (though dense) negative.

The shouldering will be even more pronounced if you use old-technology 'thick' films that have their own pronounced shoulder.

For wide latitude the combination of something like EDU and Pyro may be the worst choice you can make. EDU film also suffers from extreme reciprocity failure. At 1/25 of a second you will find it hard to tolerate any underexposure or preserve deep shadow detail. When plenty of light is available (short shutter speeds required [because of high light intensity at the film plane]) the film performs admirably. I have found it necessary to use the widest aperture possible when using EDU film and to be very careful not to overexpose.


As mentioned by several posters, ND filters will be a help in balancing the exposures. If you don't have ND filters you can always press a polarizing filter into service or use a #25 filter (or a combination of the two). For a real cut in intensity couple a deep red filter with a deep blue.

Ken Lee
13-Aug-2011, 09:34
Pyro developers tend to produce a marked shoulder


This article (http://unblinkingeye.com/Articles/PCat/PCat3/pcat3.html) shows some data to the contrary. I admit, I know very little about sensitometry - but don't see any shoulders at all. Have I overlooked something ?

For example, here's FP4+ in a popular Pyro developer, PMK:
http://unblinkingeye.com/Articles/PCat/PCat3/Fig4.jpg

On a related note, I really like how this film responds to changes in development time: TMY in Pyrocat HD (taken from the same article)

http://unblinkingeye.com/Articles/PCat/PCat4/Fig24.jpg

sanking
13-Aug-2011, 09:54
Good point, Ken,

Most modern pyro staining and tanning developers do not produce a shoulder of the type seen in old time compression developers. Rather, the curve of pyro negatives is very linear, with little toe or shoulder (though this may vary some with film type). If you print these negatives with blue sensitive papers (graded papers and AZO, Lodima) and/or with UV sensitive processes they print with a very stright line.

The idea that pyro developers shoulder is apparently due to the effect they have on the highlights when printing with VC papers, which are sensitive to both blue and green light. This is explained by Gordon Hutchins in his Book of Pyro, p. 43. "During development, the negative gains silver density from shadow to highlight. It is also gaining a proportional amount of image stain. This yellowish-green stain is not only printing density also a contrast reducing color with variable contrast paper. As the negative image increases silver and stain density, is is gaining a color mask that reduces the printing contrast. This stain reduces contrast proportionately but it is most noticeable in the highlights."

My own suggestion for the OP would be to use a film like Acros, which has very low reciprocity failure, and develop it in a pyro staining and tanning developer. No point in arguing which one as there are many useful formulas.

Sandy

nolindan
13-Aug-2011, 10:01
It is the added density component of the stain that seems to produce shouldering in the print.

If you measure the density with a densitometer then shouldering may or may not be apparent. Even using the UV channel of a graphic-arts densitometer won't accurately predict the effective density of the negative when it is printed.

How much shouldering depends on the combination of film, developer, paper, paper grade and VC filter (if used).

And some combinations of materials and processes will show less shouldering with pyro.

My experiments indicate the stain produced by pyro doesn't act as a VC filter but acts as simple density. The color of pyro stain is closer to the color of a safelight filter than it is to a VC filter. See an interminable thread on APUG for more.

Because of the high emotions that surround the use of staining developers I do not participate in discussions of the subject but simply post my own findings. I have noticed that no two people have had the same experience with the developers. Pyro is like religion in that nobody knows for sure [and is probably why emotions tend to rush in very early in any discussion].

YRWV [your results will vary]

sanking
13-Aug-2011, 14:09
Pyro is like religion in that nobody knows for sure [and is probably why emotions tend to rush in very early in any discussion].

YRWV [your results will vary]

No religion implied in my previous post. I just wanted to correct a factual error in one of your earlier posts, where you stated.

"Pyro developers tend to produce a marked shoulder - this can make highlights easier to print as they don't need burning in to preserve detail. However if you overexpose you will get rather a flat (though dense) negative."

Sorry, but this is just nonsense. Most Pyro negatives do not have a marked shoulder, and it is experience on my part (having tested several thousands of such negatives), not religion, that leads me to make this statement. You can measure the densities of a pyro stained negative in Green(Visual), Blue or UV light and you will get a very linear straight line response with most pyro formulas, depending on the characteristics of the film.

You are obviously confusing the inherent curve of a film negative with what happens when the film is used to make a positive by some specific process.

Sandy King

nolindan
13-Aug-2011, 16:15
You are obviously confusing the inherent curve of a film negative with what happens when the film is used to make a positive by some specific process.

No, I wasn't confusing the two. But I think I left some confusion in my wake by leaving the impression that I was talking about the denistometer curve of the negative - which is not the case at all

I was indeed talking about what happens when a positive is made from a negative developed in a staining developer.

It is, after all, the print that matters.

With conventional films, densitometer results translate well into what can be expected when a print is made. This is not normally the case with staining developer, though it is possible to develop a function that will correlate denistometer readings to print tones for specific densitometer/film/developer/developing method/enlarger illumination/filtration/paper combinations. There are, of course, instances where densitometer readings and print tones do indeed follow each other.

There is no reason to be up in arms about staining developers causing an increase shouldering in some material/process combinations. In most instances shouldering is a good thing. Without shouldering, small highlights in the image can be the devil when one wants to reveal any level of detail. The same applies to a toe. In both cases one trades off highlight/shadow contrast for detail preservation and ease of printing. However, if really overexposed negatives are expected, as seems to the be case in the OP's application, then a shoulder should be avoided.

I think the only intelligent advice that one can give regarding staining developers is 'try it and see if you like it'. Some do, some don't. De gustibus non est disputandum.

Jay DeFehr
13-Aug-2011, 20:09
Nicolas,

My results are much different than yours. Stain does act as a contrast filter, and it's very easy to test. Make a uniform exposure to a sheet of film and develop to a moderately high density in a staining developer. Place the processed negative over a stepwedge and contact print it on VC paper, and graded paper, and compare to prints made of the stepwedge alone on both papers. The prints made from the stepwedge alone on VC and graded papers will determine the difference in the contrast of the two papers with the given light source. Subtracting this value from the prints made with the stained film on graded and VC papers will give you the value for the contrast filter effect of the stain used in your tests. What you will find is very much in line with practical experience; when adjusted for differences in paper contrasts with the light source used, no difference in contrast will be obtained by printing the stepwedge and stained film on graded paper compared to printing without the stained film on the same paper. This is a simple test but it accounts for all the variables. One doesn't even need a densitometer to run the experiment, or calculate contrast; just count the number of steps with clear distinction on the prints. The density of the stained film doesn't matter, but developing to a moderately high density will ensure significant stain. And there's no need to bleach the silver out of the film, which could change the color of the stain. The silver is neutral density and will have no effect on the contrast of the print.

nolindan
14-Aug-2011, 08:38
My results are much different than yours. Stain does act as a contrast filter, and it's very easy to test. Make a uniform exposure ...

As you say - "My results are much different than yours"...

http://www.apug.org/forums/forum37/88869-effect-pyro-stain-vc-paper-contrast.html

sanking
14-Aug-2011, 13:15
As you say - "My results are much different than yours"...

http://www.apug.org/forums/forum37/88869-effect-pyro-stain-vc-paper-contrast.html

Thanks for the link to this thread. I had not been to APUG in a long time and was not aware of this discussion. After looking at your test results I agree with Kirk Keyes, who wrote , "The so-called evidence above does not show that the stain can affect contrast with VC papers because the tests used to derive the "evidence" were flawed in design. The flaw is that a uniform stain was applied to the step wedge exposures and that's not the state of the stain in a pyro-developed negative. The stain is not uniform, it varies proportionally to the amount of silver present in the negative."

Have you actually made the test described by Jay in a previous message? And if so, what were the results? I assume that if you have made this simple tests you would have found what is very wide practical experience, i.e. that a stained negative prints with a different contrast on a VC paper compared to a graded paper. I am curious how you explain the difference in the way a stained negative prints on VC compared to a graded paper, if it is not due to the color of the stain?

Sandy

Drew Wiley
15-Aug-2011, 10:27
Pyro squabbles again??? Well, my personal experience strongly agrees with that of
Sandy and Jay. And I've plotted enough of TMax to know that #76 does not produce
a straight line - it produces a sag in the curve, maybe not a bad one, but a distinct
sag. You can get a straighter line with HC-110, and an even better one with TMaxRS.
Pyro does not accentuate a shoulder, though this might be confused with the fact old-style TMX shouldered off more than the current version.

IanG
15-Aug-2011, 10:50
In addition to the staining effect, does developing in Pyro give a broader effective sensitivity to thick emulson films (such as Adox CHS or Arista.EDU Ultra) than standard developers such as D76, Rodinal, or Xtol?
I am anticipating using the film in an ancient camera with a single shutter speed, and Gawd knows what it is, probably around 1/25 or 1/50. I want as much wiggle room with the exposure as possible.
At least the aperture is marked F:9/11/16 which is probably ASA not the old US designation.
Diafine is not an option as for once I don't need/want the extra speed, and I've never had any luck with stand development.

Just to correct you the Adox/EFKE CHS films are thin emulsion technoloy, they pioneeered them in the early 1950's and later Kodak. Ilford etc also changed to thinner layer emulsions in the early 1960's.

The only thick emulsion "old style" films made in recent years were Fortepan 200 & 400 which were based on pre-WWII Kodak Super X and Tri-X which the plant manufacured before being taken over first by the Germans and later by the Communists.

Ian

Drew Wiley
15-Aug-2011, 11:27
With the demise of Super-XX, I'm not aware of any true thick emulsions films being made, though things like HP5 and Bergger (Forte) 200 sometimes behave similarly in certain circumstances.

IanG
15-Aug-2011, 12:51
With the demise of Super-XX, I'm not aware of any true thick emulsions films being made, though things like HP5 and Bergger (Forte) 200 sometimes behave similarly in certain circumstances.

Bergger/Forte Pan 200 is based on pre-WWII Super XX after all the Forte factory was originally owned by Kodak (UK), (not EKCo).

HP3 was quite a thick emulsion I used some in the 1960'sbut HP4 & 5 were/are different.

Ian

IanG
15-Aug-2011, 12:52
Just to correct you the Adox/EFKE CHS films are thin emulsion technoloy, they pioneeered them in the early 1950's and later Kodak. Ilford etc also changed to thinner layer emulsions in the early 1960's.

The only thick emulsion "old style" films made in recent years were Fortepan 200 & 400 which were based on pre-WWII Kodak Super XX and Tri-X which the plant manufacured before being taken over first by the Germans and later by the Communists.

Ian

Drew Wiley
15-Aug-2011, 13:21
Doesn't make sense. Bergger 200 has a distinctly finer grain and thinner emulsion than
Super XX, and doesn't respond to things like water bath etc in the same manner at all.
It appears to be a more modern emulsion than Super-XX, and resembles it only in
terms of pan sensitivity and its straight line, which won't climb to the same gamma.
In fact, I'm shooting the last of my Bergger 200 8X10 sheets this month.

IanG
16-Aug-2011, 02:19
Doesn't make sense. Bergger 200 has a distinctly finer grain and thinner emulsion than
Super XX, and doesn't respond to things like water bath etc in the same manner at all.
It appears to be a more modern emulsion than Super-XX, and resembles it only in
terms of pan sensitivity and its straight line, which won't climb to the same gamma.
In fact, I'm shooting the last of my Bergger 200 8X10 sheets this month.

You have to remember that Kodak first released Super-XX just before WWII when films were very different, their factory in Hungary continued film & paper production under the Germans, later State control.

So effectively the same pre WWII emulsions evolved in different ways, Forte's emulsions were improved with help from Bergger but would have been slowly evolving anyway prior to that.

The Forte/Bergger 200 isn't that fine grained compared to modern Tri-X or HP5 but it's still not bad. I discovered that the 3 boxes of 10x8 EFKE PL25 I thought had are actually Fortepan 200 from the last production run - there's only a tiny sticker with the Emulsion name etc.

Ian

Bill_1856
17-Aug-2011, 18:59
I have several hundred sheets of 4x5 Berreger 200 and 9x12 Efke 100 in my freezer. Do these qualify as thick emulsion films?
Thanks.

fridrik
18-Aug-2011, 12:33
Regarding the pyro discussion above. I maybe a simple general-purpose-developer-user but how could pyro (or any other developer for that matter) change the shoulder of a curve. To my understanding the shoulder is just a function of the silver content of the film emulsion so that when you expose and develope such that all silver is released then you have a shoulder appearing. So this is only dependent on the film you use and has nothing to do with the developer. (This is of course assuming that the process doesn't somehow reduce the silver content of the emulsion and thus lowering the shoulder.)

IanG
18-Aug-2011, 12:39
I have several hundred sheets of 4x5 Berreger 200 and 9x12 Efke 100 in my freezer. Do these qualify as thick emulsion films?
Thanks.

Only the Fortepan 200 )Bergger) is thick emulsion, the EFKE is thin.

Ian

nolindan
18-Aug-2011, 12:40
how could ... [a] developer ... change the shoulder of a curve.

I don't know about the 'how', but for some examples of curve shifting with developers see most any good film data sheet. For example http://www.kodak.com/global/en/professional/support/techPubs/f32/f32.pdf Kodak TMax film -- see page 15 for some curves: upsweeps, downsweeps, bumps in the middle ... these deviations look small until you take the derivative of the HD transfer function to plot contrast Vs. density.

Drew Wiley
18-Aug-2011, 13:45
Every combination of film and developer and film can affect curve shape. Even the
color of filters or long-exposure recip characteristics can significantly change it.
Staining developers like pyro change it in another manner, that is, relatively to the
spectral sensitivity of the printing paper. Sometimes these various distinctions are
significant.

Drew Wiley
18-Aug-2011, 13:51
I certainly woudn't call HP5 plus finer-grained than Bergger 200, though with pyro it
does have a less grainy look due to the so-called watercolor effect of filling between
grain while still accentuating mackie line effect. Somewhere I heard the rumor that Super-XX was made in the EU all along. If anyone thinks that Bergger 200 is a true
thick emulsion like Super-XX was, just try an old-fashioned trick like water bath or
hot/cold reticulation tricks and compare the two films. Totally different. Of course,
this is getting to be largely academic, since sadly, both films have been discontinued.

nolindan
18-Aug-2011, 18:21
Staining developers like pyro change it in another manner, that is, relatively to the spectral sensitivity of the printing paper.

And that effect changes with changes in the light source spectrum: cold-light heads image pyro stain differently than halogen/color heads which behave differently than PH211 et. al. bulbs. And pyro stain interacts with the color of VC filters in rather strange ways.

With all the interactions it isn't surprising there is often disagreement about the effects of staining developers.

fridrik
19-Aug-2011, 03:09
I don't know about the 'how', but for some examples of curve shifting with developers see most any good film data sheet. For example http://www.kodak.com/global/en/professional/support/techPubs/f32/f32.pdf Kodak TMax film -- see page 15 for some curves: upsweeps, downsweeps, bumps in the middle ... these deviations look small until you take the derivative of the HD transfer function to plot contrast Vs. density.

Yes I understand that the developer can affect the curve shape locally (as in the datasheet), however the developer can not add silver to the negative so the shoulder location (on the density or y-axis in the film curve data) should be unchanged. I have heard of some process that can wash away silver and thus lower the shoulder.

Now as I understand it, Pyro has contrast increasing staining affect which does help you in controlling your exposure/developement such that not to reach the shoulder (by effectively reducing contrast and using the staining effect for compensation.) For those here that use pyro, does this make sence?

Fridrik

Greg Blank
19-Aug-2011, 05:39
Yes I understand that the developer can affect the curve shape locally (as in the datasheet), however the developer can not add silver to the negative so the shoulder location (on the density or y-axis in the film curve data) should be unchanged. I have heard of some process that can wash away silver and thus lower the shoulder.

Now as I understand it, Pyro has contrast increasing staining affect which does help you in controlling your exposure/developement such that not to reach the shoulder (by effectively reducing contrast and using the staining effect for compensation.) For those here that use pyro, does this make sence?
Fridrik

No, it does not make sense. Pyro does not increase contrast. All developers are reducing agents, Your film starts with a given silver density, areas that had the least exposure have the silver removed by the developer, areas with the most exposure there is less removal of the silver. The Yellow Pyro stain acts like a yellow filter in these high density highlight areas, yellow filters actually decrease the contrast when printing, affecting the blue sensitive part of your printing paper. So depending on what paper you are using the effect of the stain will be more or less apparent.

Cor
19-Aug-2011, 05:54
Perhaps I can plug in my post (http://www.largeformatphotography.info/forum/showthread.php?t=79630) of yesterday of an example of how the Pyro stain affects contast too much in my system (btw I use a tungsten/opal lamp and individual grade filters in my condensor Durst L1200)

Best,

Cor

Greg Blank
19-Aug-2011, 06:10
Perhaps I can plug in my post (http://www.largeformatphotography.info/forum/showthread.php?t=79630) of yesterday of an example of how the Pyro stain affects contast too much in my system (btw I use a tungsten/opal lamp and individual grade filters in my condensor Durst L1200)

Best,

Cor

You are doing a lot of fancy dancing, that most folks don't do with standard Pyro developers. I am not sure you know what all that does, but I will state that; simple Pyro developers act exactly how I stated, after 20 years and many hundreds of Pyro developed negatives in that time frame, I think what say I is correct. Pyro cat does behave differently than say PMK - which I use. My brief Pyro cat experience was that Pyro Cat dropped a lot of the actual film speed and did produce more contrast as a result of only the highlights recieving development.

fridrik
19-Aug-2011, 06:44
Thanks for the response Greg, I have never used pyro and only heard of it's staining effect. I clearly got it wrong, in any case the staining does affect contrast when printing (depending on paper.)

Cor
19-Aug-2011, 10:01
You are doing a lot of fancy dancing, that most folks don't do with standard Pyro developers. I am not sure you know what all that does,

..mmm maybe it's a language thing, I think we basically agree, and I think my example is indeed rather extreme, but for me very convincing...but I do not like the tone and your assumptions in your comment...

Cor

Drew Wiley
19-Aug-2011, 10:15
Different kinds of pyro developers generate somewhat different results with different
film and paper combinations, and how different light sources are actually used. So it all boils down to the specifics, which have been studied and argued on numerous contentious threads. But back to a more basic question: development method can IN
EFFECT significantly affect film shoulder in an indirect way, because one should calculate personal film ASA based upon shadow value. Many times a developer with inadequate shadow separation will force one to produce "thick" or over-exposed negatives, and this ends up blocking the high values where the shoulder tapers off. I've seen the effect of this many times, even in the work of relatively famous photographers. They get comfortable with a particular film and developer then try to tweak the best theycan. Staining developers like pyro can unquestionable help the reproduction of highlights, but in many cases will do less to salvage poorly exposed shadows - that's more a function of seeking a straighter line down toward the toe of the film. But we can get into just as much argument about that arena as the other
portions of the film curve, simply because there are so many potential specifics,
and so many different kinds of look we are each trying to achieve.

Greg Blank
19-Aug-2011, 21:34
..mmm maybe it's a language thing, I think we basically agree, and I think my example is indeed rather extreme, but for me very convincing...but I do not like the tone and your assumptions in your comment...

Cor

Maybe :D, Half tone or Mono? I never assume. So why are you removing the stain? We have heard of printing from the stain after removing silver,.. but if you are using a staining developer and then removing the very reason for using it,...well it raises eye brows!

Cor
20-Aug-2011, 00:15
Maybe :D, Half tone or Mono? I never assume. So why are you removing the stain? We have heard of printing from the stain after removing silver,.. but if you are using a staining developer and then removing the very reason for using it,...well it raises eye brows!

Perhaps I did not made it clear in my original post:

I occasionally obtain heavy overexposed negatives when shooting IR film and processing in PyrocatHD.

More silver is more stain.

A lot of stain acts as a low(ering) contrast filter in my condensor enlarger and VC filters on Ilford MG IV RC.

This overexposed negative is in my hands not really printable (a snappy contrasty print), increasing the grade does not help due to heavy stain.

Bleaching this stain away returns life again , the negative prints nice again,
especially the highlights are bright and detailed again .


Without complex explanations this is obvious and direct to me, yes it is not your average Pyro stained negatives, and it is a not for everbody and it is tedious..

I was a bit annoyed by your remark that I did not know what I am doing..cannot boast hunderds of Pyro negtives in 20 years, but I am now newby either, and I think I have a good understanding what I am doing, have done these things before..

Best,

Cor

Greg Blank
20-Aug-2011, 16:11
That sounds more lucid, Thanks.


Perhaps I did not made it clear in my original post:

I occasionally obtain heavy overexposed negatives when shooting IR film and processing in PyrocatHD.

More silver is more stain.

A lot of stain acts as a low(ering) contrast filter in my condensor enlarger and VC filters on Ilford MG IV RC.

This overexposed negative is in my hands not really printable (a snappy contrasty print), increasing the grade does not help due to heavy stain.

Bleaching this stain away returns life again , the negative prints nice again,
especially the highlights are bright and detailed again .


Without complex explanations this is obvious and direct to me, yes it is not your average Pyro stained negatives, and it is a not for everbody and it is tedious..

I was a bit annoyed by your remark that I did not know what I am doing..cannot boast hunderds of Pyro negtives in 20 years, but I am now newby either, and I think I have a good understanding what I am doing, have done these things before..

Best,

Cor

onnect17
20-Aug-2011, 21:19
Jay and Sandy,
I tested the two speeds in the Jobo and the negatives with the higher speed (more agitation) are much better (by far) compared to the slower speed. For this test I used 510-pyro. Pyrocat-HD will be next.

Jobo CPE-2, with 2521 tanks and 2509 reels
HS=65 rpm, SP=25 rpm
510-pyro, 1:100 @ 75F, 5:30 mins
TMX in 35mm

I'm sure the reason for the big difference in density is the staining effect of the pyro. With regular developers is a different story.

Jay DeFehr
21-Aug-2011, 09:29
Hello all,

The effects of staining developers are much better understood than this thread might suggest. These discussions are often derailed by language and terminology, and by simple misunderstanding of the principles at work. To keep things relatively simple, I'll confine my initial remarks to the effects of stained negatives on graded silver paper, with the understanding that the same principles apply to all UV printing processes, as well.

Image stain is formed as a product of development, and in proportion to it; more stain with more development, and stain produces print density. Print density is the result of the combination of silver density and stain intensity. If a given film developed to its Dmax in a non-staining developer produces print density X, The same film will, when developed to Dmax in a staining developer, produce print density X+Y, where X represents print density obtained by silver density, and Y represents print density obtained by stain intensity, thereby extending the Density Range of the negative, and relocating the shoulder further up the scale.

Greg Blank,

You're mistaken on several points. Pyro can increase contrast, as described above, but it's also true that very low contrast negatives can be made with staining developers. Your description of the film developing mechanism is not at all accurate, or useful. The silver present in an undeveloped film is in the form of silver halide. The developer reduces the silver halide to silver metal, making it opaque/black; the developer does not remove any silver from the film. The fixer removes all undeveloped silver halide from the film, making the film transparent where there was no development (or fog, etc).

The effect of stained negatives on VC papers is much more complex. The stain does act as a low contrast filter, as my simple test demonstrates, but it also creates print density, which would seem to increase contrast. To understand the effect of stain on VC paper, it is useful to print with a color head and a color analyzer. Most color heads use a halogen lamp, which produces light in the yellow end of the spectrum. Many VC printers who use color heads are accustomed to balancing their light source to neutral by the addition of magenta (minus yellow) filtration. This neutral point is said to produce the equivalent of grade two on VC paper. This is fairly simple and straightforward if one is printing non-stained negatives, because the entire paper is exposed to the same color of light, producing a single contrast grade. The proportional nature of image stain, however, produces a quite different effect. Since the stain is proportional- most intense in the highlights, and almost absent in the low values, stained negatives alway print on VC paper with a split grade effect.

A stained stepwedge negative can be instructive here. If you place the stepwedge in the negative holder of your enlarger, and position your analyzer probe within the least dense step on your easel, you can zero your analyzer with a few units of magenta. Move the probe to the next step, and a few more units of magenta will be required to zero the analyzer. This will continue as you move up the density scale of the stepwedge, until at the last step, 100 units, or more might be required to zero the analyzer, and at this point your densest highlights will print without any yellow filter effect from your stained negative, but what's happening in the low values? In the low values, where only a few units of magenta zeroed the analyzer, there is now enough magenta filtration to print those areas at the highest grade your paper can achieve, likely blocking much of the detail there. If you turn the magenta filtration down to print those areas at a normal grade, the yellow filter effect of the stain in the highlights will be intense, so it's always a matter of finding the best balance for the image being printed, but it will always print with a split-grade effect.

Armando,

Better how?

onnect17
21-Aug-2011, 14:18
Jay,
Better perhaps is not the right word. Let's say closer to what I'm looking for: high density, plenty of stain in the image, no stain in the base.

Jay DeFehr
21-Aug-2011, 14:35
Armando,
Please understand I'm not being critical, or disagreeing in any way, but to make a valid comparison of the effects of slow rotation vs fast rotation, you need o control the variables of your experiment. At the minimum, you should develop two films of identical exposures to a common contrast, one using slow rotation, the other using fast rotation. I'm not sure your experiment tells us much, except that more agitation produces more development, which I think we all expected. If it were true that higher rotation speeds produce more image stain than slower speeds, without producing more general stain, or streaks, or other development defects, that would be a useful discovery, but to prove it experimentally, you need to control your variables, and isolate the tested one. I don't mean to suggest you're under any obligation to prove anything, experimentally or otherwise, to anyone, I'm just trying to point out some of the reasons your results might be inconclusive.

onnect17
21-Aug-2011, 14:51
Jay,
You point is totally valid and of course, any questioning or critique is welcome because I could be missing something important affecting the test.
As you mentioned I developed two strips of films.
The tests were conducted in the same location, same equipment, same temperature (75F, and 72F in the room), same emulsion ( 3 or 4 frames each) of the same roll (tmx) shot with the same camera, same gallon of distilled water, same 510 pyro batch.

Drew Wiley
21-Aug-2011, 14:55
Stain is proportional, so you're always going to have at least a little stain in the base, especially with thick emulsion films. What high density means in practical terms is a function of several variables, including the sum of the stain and silver density itself (it's easy to go overboard in this respect), and the spectral sensitivity
or sensitivities of the print medium.

onnect17
21-Aug-2011, 15:25
Drew,
The base of the emulsion in the strips used for the test is on the gray/blue side. The stain in the image is sort of sepia.
Also, next to me I have some 4x5s developed in pyrocat-hd showing some stain in the base (no blue or gray at all).
I will develop some 4x5's tonight in 510-pyro and see what happen.

Greg Blank
21-Aug-2011, 16:19
*Was not helpful - Ok.

Developers certainly reduce silver. Where there was less exposure less silver remains that is true. A sheet of film starts with a given overall density potential. More exposure activates more or the most silver in a given area, all films have a maximum potential based on exposure and development. Since exposure/development is a electomagnetic/electrochemical process, once the silver on the exposed sheet is solvent released it is free to travel to an area that still has an electromagnetic charge. Stop bath halts the charge taking place in the developer and on or in the the film, Fixer bonds sulfer molecules to the silver to sulfide them. Anything that as you say was deposited or reduced to silver halide is now bonded with the sulfide. Any unexposed areas, and therefore inactive ones did remain inactive and the silver washes away, but the fixer did nothing to these areas they are empty before hitting the fixer, shadow areas develop to completion in the first 3 minutes or less of development time.

If we say that under a very controlled exposure and development a normal negative is desired and produced that negative will print on grade two paper with or without additional filtration. In otherwords if you have no filter between the light,negative and a MC paper the result will measure to be grade 2 ideally. If you used a grade 2 graded paper or MC however with a subject other tahn say a grey card, my experience for a more pleasant rendition calls for about 1/2 grade more contrast. If you are printing with a PMK negative if you have a highlight value beyond say 1.15 the highlight value will be easier to print. A stained negative should not produce a stain of more than .15 value in the shadow areas or the true black areas will be too high in overall value. But that me printing VC papers. I will furthermore once again state that no developer produces contrast, by this I mean the developer component, this excludes the accerator, borax, metaborate, sodium hydroxide etc. Those also directly affect the stain and stain density. Agitation will directly affect the stain for better or worse in my opinion as does oxidization. Oxidization will increase general stain which is one more reason I advocate splitting Pyro developer into two increments in the Jobo for the total time required.




Hello all,

The effects of staining developers are much better understood than this thread might suggest. These discussions are often derailed by language and terminology, and by simple misunderstanding of the principles at work. To keep things relatively simple, I'll confine my initial remarks to the effects of stained negatives on graded silver paper, with the understanding that the same principles apply to all UV printing processes, as well.

Image stain is formed as a product of development, and in proportion to it; more stain with more development, and stain produces print density. Print density is the result of the combination of silver density and stain intensity. If a given film developed to its Dmax in a non-staining developer produces print density X, The same film will, when developed to Dmax in a staining developer, produce print density X+Y, where X represents print density obtained by silver density, and Y represents print density obtained by stain intensity, thereby extending the Density Range of the negative, and relocating the shoulder further up the scale.

Greg Blank,

You're mistaken on several points. Pyro can increase contrast, as described above, but it's also true that very low contrast negatives can be made with staining developers. Your description of the film developing mechanism is not at all accurate, or useful. The silver present in an undeveloped film is in the form of silver halide. The developer reduces the silver halide to silver metal, making it opaque/black; the developer does not remove any silver from the film. The fixer removes all undeveloped silver halide from the film, making the film transparent where there was no development (or fog, etc).

The effect of stained negatives on VC papers is much more complex. The stain does act as a low contrast filter, as my simple test demonstrates, but it also creates print density, which would seem to increase contrast. To understand the effect of stain on VC paper, it is useful to print with a color head and a color analyzer. Most color heads use a halogen lamp, which produces light in the yellow end of the spectrum. Many VC printers who use color heads are accustomed to balancing their light source to neutral by the addition of magenta (minus yellow) filtration. This neutral point is said to produce the equivalent of grade two on VC paper. This is fairly simple and straightforward if one is printing non-stained negatives, because the entire paper is exposed to the same color of light, producing a single contrast grade. The proportional nature of image stain, however, produces a quite different effect. Since the stain is proportional- most intense in the highlights, and almost absent in the low values, stained negatives alway print on VC paper with a split grade effect.

A stained stepwedge negative can be instructive here. If you place the stepwedge in the negative holder of your enlarger, and position your analyzer probe within the least dense step on your easel, you can zero your analyzer with a few units of magenta. Move the probe to the next step, and a few more units of magenta will be required to zero the analyzer. This will continue as you move up the density scale of the stepwedge, until at the last step, 100 units, or more might be required to zero the analyzer, and at this point your densest highlights will print without any yellow filter effect from your stained negative, but what's happening in the low values? In the low values, where only a few units of magenta zeroed the analyzer, there is now enough magenta filtration to print those areas at the highest grade your paper can achieve, likely blocking much of the detail there. If you turn the magenta filtration down to print those areas at a normal grade, the yellow filter effect of the stain in the highlights will be intense, so it's always a matter of finding the best balance for the image being printed, but it will always print with a split-grade effect.

Armando,

Better how?

Drew Wiley
21-Aug-2011, 16:46
I gave up on doing pyro with sheet film in drums. Not that I got unacceptable results, but the base fog was a little annoying. Since then all sorts of pyro tweaks have been formulated to improve this. But over the last hour, since my last post,
I did a tray stack of TMY sheets in PMK, and in consideration of the given question,
estimate the pyro stain in the borders to be only a few points above the film base,
perhaps around .07 total density as opposed to .04 in a clean-working conventional developer. TMax films tend to give very low fbf in general, but then, they aren't thick emulsion films either. That's the nice thing about TMY 400 - it gives results a lot like older classic films with a straight-line, but with a clean base and much finer grain.

Drew Wiley
21-Aug-2011, 16:53
Armando - Pyrocat does seem to render a brownish stain, whereas PMK etc gives yellow-green. If the unexposed borders of the film are unduly stained, this would
indicate excess aerial oxidation from over-agitation or perhaps from old developer
(which would probably look muddy overall, whereas overagitation would produce
very dense highlights). Unfortunately, "pyro" is a term for two completely unrelated
chemicals which both produce proportional stain, so end up in analagous use.

Greg Blank
21-Aug-2011, 17:13
estimate the pyro stain in the borders to be only a few points above the film base,
perhaps around .07 total density as opposed to .04 in a clean-working conventional developer. TMax films tend to give very low fbf in general, but then, they aren't thick emulsion films either. That's the nice thing about TMY 400 - it gives results a lot like older classic films with a straight-line, but with a clean base and much finer grain.

That mirrors my findings. I get a few points above FB+F usually .07 to .09 with Delta 100. If you get the urge, try putting a small amount of Amidol like a small chemical spoons worth. My experience is it gives a bit more punch to the negatives.

Jay DeFehr
21-Aug-2011, 19:03
Armando,

It seems you can be fairly certain the increased agitation is responsible for the increased development, but what we still don't know is how different from your more developed negative one developed to the same contrast at lower speed would be. What your test seems to show is that the two rotation speeds lie within the range in which increased rotation speed results in increased development, and that the faster speed doesn't cause streaks or other defects including increased general stain, even when developed to a higher contrast. None of these were foregone conclusions, so your test was not a wasted effort. It might very well be the case that development at the higher rotation speed for a shorter duration produces better results than lower rotation speed for a longer duration, but your test doesn't show this, because the two films were developed for the same time instead of to the same contrast, which is a more demanding test.

510-Pyro was designed for just the scenario you've tested. The ascorbic acid content was optimized for very vigorous agitation and development to high contrast without producing significant general stain. I think you'll get different results from the same test using Pyrocat HD.

onnect17
21-Aug-2011, 20:10
Jay,
I scan most of the negatives so I'm OK with densities above 3.0. Also the brown stain give me differents contrast levels in each channel if scanning in color mode.

I think I will use a dilution of 1:200 next time for 510-pyro. Something tells me the developer is very active with agitation. I'll let you know.

In the meantime, here's a one of the shots developed at high agitation (no part of control strip, of course).

fridrik
22-Aug-2011, 05:01
A lot of information here, thanks!
I would like to ask then, for grade paper does the stain work similarly as toning the negative in selenium? Also can you explain what is the effect that produces the stain, does it affect longevity of the negative?

Cor
22-Aug-2011, 05:39
A lot of information here, thanks!
I would like to ask then, for grade paper does the stain work similarly as toning the negative in selenium? Also can you explain what is the effect that produces the stain, does it affect longevity of the negative?

Indeed the stain works as added density when you switch to a graded paper, another benefit of the Pyro stain is that you obtain a dual purpose negative: I print my 8*10 negatives both as silver gelatine print and as pure Platinum prints, because under UV the stain acts as extra density, density needed in alt. photo processes.

As far as I know the stain is as archival as the silver image, but perhaps other people have more definitive information.

Best,

Cor

Jay DeFehr
22-Aug-2011, 08:10
Very nice, Armando!

Drew Wiley
22-Aug-2011, 08:30
Greg - I found tweaking pyro with amidol a bit unpredictable, simply because the action of this chemical is much more fussy than when used as a print developer, and
miniscule differences in quality or freshness had a significant effect. Even when I
used the best stuff I could find it was a bit of a crap shoot.

Greg Blank
22-Aug-2011, 16:39
Greg - I found tweaking pyro with amidol a bit unpredictable, simply because the action of this chemical is much more fussy than when used as a print developer, and
miniscule differences in quality or freshness had a significant effect. Even when I
used the best stuff I could find it was a bit of a crap shoot.

I honestly have never seen that sort of issue, been using the same batch of amidol for over ten years, when I run out in 2015 or so, maybe I will.

onnect17
25-Aug-2011, 20:57
Very nice, Armando!

Thanks Jay,
Here's another shot, this one developed in Pyrocat-HD at high speed for 10 min ended up with a lower max density (compared to around 5 min for 510-pyro)
The 1:200 test still pending.

bobherbst
26-Aug-2011, 05:40
Pyro image stain is more archival than the silver. Attached are two images for illustration. The first is a scan of a negative on which virtually all of the silver is gone. The negative was shot around 1910, is on nitrocellulose film, and was developed in pyro. As you can see, there is virtually no silver left - only stain. The second image is how this negative prints on Azo grade 2.


As far as I know the stain is as archival as the silver image, but perhaps other people have more definitive information.

Best,

Cor

Ken Lee
26-Aug-2011, 07:15
That's a very interesting observation Bob - Thanks for sharing !

Drew Wiley
26-Aug-2011, 08:11
Greg - I guess you're lucky with the amidol. I had a pharmaceutical supplier tell me that
amidol varies somewhat from batch to batch, and that photographic applications are
actually more fussy than the medical usage. Since I typically bought it a hundred grams at a time, there just wasn't enough consistency to trust it with fine-tuning a
pyro tweak.

onnect17
26-Aug-2011, 16:41
Thanks Bob! Quite interesting.

Jay DeFehr
26-Aug-2011, 22:28
Thanks Jay,
Here's another shot, this one developed in Pyrocat-HD at high speed for 10 min ended up with a lower max density (compared to around 5 min for 510-pyro)
The 1:200 test still pending.

Armando,

That's what I would have predicted. Catechol is not as robust as pyro, in general, and 510-Pyro is more robust than any pyro developer I know. When I reformulated Hypercat, my catechol developer, I let the developer determine the formula and the optimum development method, and this resulted in a very simple developer that performs remarkably well within its limitations. Formulating a catechol developer for rotary development required too much compromise, and in the end, resulted in a developer that was only nearly as good as 510-Pyro. Hypercat is a different class of developer than 510-Pyro, and outperforms it in some ways. The two developers are not interchangeable, and are not meant to be. I don't think Hypercat would fare any better than Pyrocat HD did, in your test.

Thanks for posting your results, and your images.

Greg Blank
27-Aug-2011, 05:43
Maybe, For my particular case I bought 100 grams quite a few years ago, I don't use it it for any other purpose than PMK use. I got it from Artcraft, I then put the Amidol into a plastic pill bottle and then inside a ziplock bag.


Greg - I guess you're lucky with the amidol. I had a pharmaceutical supplier tell me that
amidol varies somewhat from batch to batch, and that photographic applications are
actually more fussy than the medical usage. Since I typically bought it a hundred grams at a time, there just wasn't enough consistency to trust it with fine-tuning a
pyro tweak.