PMK to Pyrocat HD or PCTEA?

[noseoil]

With 2 years of darkroom experience behind me now, I'm wanting to try another film developer. I've been using PMK and have been pleased with results, but... There is the issue of cloudiness in shadow detail which I'm not pleased with, especially in contact printing.

I've used ABC pyro, but have found it too fickle and energetic for casual use with the slow films I prefer (25 and 100). It does yield fine negatives with razor sharpness, but is more labor, cost and chemistry intensive than PMK.

My concerns are these. I want a long shelf life, as I can go for weeks at times without developing at times and don't want to have to mix fresh stock (B in ABC, for example). Shadow values need to be crisp, not muddy (PMK's major drawback). Highlight values seem to be best with pyro, so I would like to stay with a developer which can mask with a proportional stain affecting these values.

I'm not really too concerned with speed, as shooting at asa 12 (PMK) and asa 3 (ABC) with 25 speed film is not a problem now, although there are limits to DOF and shutter speeds. Both Pyrocat and PC TEA seem to be easy to use one shot developers which are very cost effective. Any ideas? thanks, tim

 

[Donald Miller]

Tim,

I have not used the TEA formulations so I really can not comment in that regard. I have found Pyrocat to be preferable to PMK because of the issue of the color of stain if for no other.

I am not alone in realizing this issue. Howard Bond in his recent studies in PhotoTechniques addressed this issue as well. The PMK stain color, while proportional, will act as a contrast reduction factor on VC materials in the highlight regions. Of course if one is using graded materials this will not apply.

I have found that the sharpness and tonal scale with Efke PL 100 4X5 (minimal agitation) will rival a contact print in enlargements up to and including 11X14.

The issue of poor shadow tonal separation that you raise could be partly due to the film that one is using. If a given film chararacteristic curve has a long toe and the exposure is placed on the toe then the result will be poorly differentiated shadow tonal scale. Taking TriX developed in HC 110, for instance, I have found that the EI for that film (based on densitometric evalutation) is 160 but in actuality when I place my shadow exposure on Zone IV then I am actually adjusting the EI to 20. That is what many photographers do because of the characteristics of the film curve. There is really no other way to evaluate a film properly other then to evaluate or even to plot the curve if it is not readily available. I aplologize for my digression but felt that this needed to be addressed for evaluation of the matters that you raised.

 

[noseoil]

Donald, thank you for your input. I'm aware of the film toe's threshold and yes, I have underexposed a time or two. After comparing ABC and PMK with respect to shadow values, the ABC is much better in a scene by scene comparison. My concern with shadow placement on zone IV is the subsequent lifting of zone VIII into the shoulder and a loss of detail in highlights. This is certainly more critical with Efke 25 than it is with Efke 100.

 

[gainer]

PC-TEA is, of course, a non-staining developer in a concentrated stock solution containing only phenidone, ascorbic or erythorbic acid and triethanolamine that requires nothing but water to activate it. The stock solution alone will not develop film. It lasts a very long time on the shelf. One can substitute pyrogallol or catechol for the ascorbic acid to obtain a staining developer concentrate with the same keeping qualities and the same need for water only in order to make active developers.

I have found that when one uses PMK or one of my staining developers with VC paper, the shadows are there but need a little local contrast to bring them up. I use about 30M filtration or an Ilford #3 filter. The same negative prints very well on #2 graded paper because the colored part of the image is seen as extra silver by the blue sensitive paper. As has been pointed out by others before me, the pyro image is usable also with those alternative processes that require a very high contrast negative.

 

[Mongo]

Tim-

I can tell you that Efke 100 in Pyrocat-HD is my favorite combination by far. I'm only doing contact printing (on Azo and on both graded and VC fiber papers), and the results have been gorgeous. I get excellent separation of shadow detail and negatives that I can use for either type of paper easily, all from a developer that's inexpensive and seems to keep forever.

I have not tried PC-TEA yet, although I will be doing so in the new year. Unfortunately, I have not developed any Efke 25 with Pyrocat-HD, as my current personal project is limited to Efke 100 only. I'll be interested to hear what others have to say about Pyrocat-HD and Efke 25.

Be well.
Dave

 

[Donald Miller]

Donald, thank you for your input. I'm aware of the film toe's threshold and yes, I have underexposed a time or two. After comparing ABC and PMK with respect to shadow values, the ABC is much better in a scene by scene comparison. My concern with shadow placement on zone IV is the subsequent lifting of zone VIII into the shoulder and a loss of detail in highlights. This is certainly more critical with Efke 25 than it is with Efke 100.

Tim,

Thanks for your thoughts. I would like to comment on your concerns about the Zone VIII "fall" in the example that you have provided.

The Zone VIII density would be a condition of exposure, certainly. But it would also involve the film and the development times.

As I review the characteristic curve for Efke 25 as found on the JandC site, I find that this film exhibits a perfectly linear straight line once one departs from a slight toe (except in cases of greatly extended development). I would not consider the film's shoulder when I exposed this film.

Other films may incorporate this consideration but Efke 25 does not appear to be among those.

 

[noseoil]

Donald, my concern was that putting the shadow values on zone IV instead of III would compress the top end of the film's range and crowd the top end. You are saying that a shift of one stop up the curve will not affect the highlights, but just move everything up a notch and add density to the negative, requiring more time in printing.

Development time can remain the same without causing problems? I'm seeking a clarification of your statement, as I was concerned that by adding a stop of exposure I would have to reduce development times to keep things the same. Perhaps my understanding, specifically with respect to Efke 25, has been wrong all along. Thanks.

 

[Donald Miller]

Donald, my concern was that putting the shadow values on zone IV instead of III would compress the top end of the film's range and crowd the top end. You are saying that a shift of one stop up the curve will not affect the highlights, but just move everything up a notch and add density to the negative, requiring more time in printing.

Development time can remain the same without causing problems? I'm seeking a clarification of your statement, as I was concerned that by adding a stop of exposure I would have to reduce development times to keep things the same. Perhaps my understanding, specifically with respect to Efke 25, has been wrong all along. Thanks.

Tim,
According to the characteristic curve that JandC has posted in the Efke technical section on their site, Efke 25 will develop all sorts of density range well beyond what we require for any photographic process today. Recognizing of course that the developer that they are using is not Pyrocat, the density range for a four minute developing time has no shoulder and a density range above 2.00 with no shoulder shown. At seven minutes the density range is above 2.60 with the most subtle shoulder. At 10 minutes the density range is above 3.00 and a subtle shoulder albeit slightly more then the seven minute development time.

Recognizing that I want a density range of 1.55-1.65 for grade two Azo and Pt-Pd would be 1.65-1.75 you can see that this film has a great deal of expansion potential.

I have not used this film myself but I would think that this film could be exposed at EI 25 placing the shadows at Zone IV (Actual EI of 3) and this film would work wonderfully at N and N+ development.

If one were to need two or three zones of expansion this film could be exposed at EI 6 or 12 with wonderful expansion capabilities. In fact if one could deal with the slow emulsion this is one of the better films for expansion today based on the material provided on the JandC site.

I would think that a good choice of two films would be Efke 25 for expansion and HP 5 for contraction. That is if the slow film speed with the Efke 25 would not be problematic in your application.

I hope that this answers your question.

 

[noseoil]

Don, thank you for your explanation. It makes sense. tim

 

[roteague]

View Camera magazine had an article a few months ago (May/June??) about PMK and Pyrocat HD. Worth reading.

 

[Donald Miller]

View Camera magazine had an article a few months ago (May/June??) about PMK and Pyrocat HD. Worth reading.

It may be interesting to do a search on this site of the discrepency involved in the View Camera testing procedures pertinent to this article. As I recall this involved an article that Jorge wrote and submitted to View Camera only to have Steve Simmons ignore it. Simmons then went on to write his own article based in nothing more then pure hypothesis with no substantiating scientific basis.

 

[roteague]

(there was a url link here which no longer exists)

 

[noseoil]

Robert, thank you for the link to Sandy's pyrocat discussion on APUG. I had forgotten about the thread.

After reading a copy of Jorge's article which he had submitted to VC, the subsequent online comments by Steve and finally the article in VC showing the two developers side by side, I have decided there was not enough objective information to be found to make a decision. This comment is based on Steve's article and certainly not on Jorge's, which I found to be very interesting.

At this point, I'm leaning heavily toward Pyrocat HD as my developer of choice for the next year. I need to decide based on limited funds and experience, so the replies I have recieved are very helpful.
This is certainly a wonderful forum and I appreciate the time others (especially Donald) have taken to help me with my decision. It sounds like the Pyrocat HD and Efke film combination, both 25 and 100, is a winner from what I have been told, read and seen (Francesco's work). I'm looking forward to trying minimal agitation with Efke 25 for enlarging with rollfilm and 8x10 for contact printing.

 

[Mongo]

Tim-

Good luck with your new adventures. One thing that I am sure of is that you will be happy with Pyrocat-HD and Efke 100. I'd love to hear about your experiences with the same developer and Efke 25.

Last night I was contact printing an 8x10 that will go into a portfolio I'm presenting to selected friends this Christmas, and I am still amazed at the combination of Efke 100 and Pyrocat-HD. Prints on Azo and on warm-tone VC fiber paper are stunningly beautiful.

Be well.
Dave

 

[sanking]

It sounds like the Pyrocat HD and Efke film combination, both 25 and 100, is a winner from what I have been told, read and seen (Francesco's work). I'm looking forward to trying minimal agitation with Efke 25 for enlarging with rollfilm and 8x10 for contact printing.

I have posted quite a bit of information about Efke PL100 and Pyrocat-HD on the AZO forum so you should be able to find some good development information there.

Several months ago I had a chance to test some Efke 25 film. It is, as one might imagine, quite high in contrast and offers fairly good expansion and contraction potential, but not nearly as much as Efke 100. My data for this film is rather limited but here is what I would suggest for development with Pyrocat-HD. This is based on rotary processsing in tubes at 72ºF.

For regular silver printing. 1:1:100 dilution

N 6:00 minutes
N+1 12:00 minutes
(For N- development use a weaker dilution, say 1:1:150)

For printing on AZO#2

N-3 5:00 minutes
N-2 6:00 minutes
N-1 9:00 minutes
N 16:00 minutes
(For N+ development use the 2:2:100 dilution)

Efke 25 is a super sharp and very fine grain film, but there is not much latitude, either for exposure or development, so for best results one really needs to test the material.

Sandy

 

[noseoil]

Sandy, thanks for posting this information. I do remember you post on the azo forum.

How's the book? Any date yet for publication? tim

 

[roteague]

At this point, I'm leaning heavily toward Pyrocat HD as my developer of choice for the next year.

You know, every time I look at Francesco's work I think the same thing. I'm not big on architectural studies, but I am deeply impressed with the tonal range his images have.