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Blueberrydesk
16-Apr-2007, 13:10
Hello all. I'm confused by something in Gordon Hutchings' book of Pyro that is probably just a misunderstanding on my part, but I figured I'd ask the experts.

On page 11 the statement is made that film developed in PMK should be exposed to produce "underexposed" silver density. I read this as saying that PMK does better with slightly underexposed images.

However, on page 45 under Exposing Negs for Optimum printing, it is stated that "if the shadow areas receive too little exposure, the shadows will look dark and muddy in the final print." and then goes on to state that it's not possible to get optimum values in the print if the neg has been underexposed.

I apologize to Mr. Hutchings if he takes exception to my posting a small excerpt of his wonderful book, but this part has me baffled. I'm pretty much a complete noob when it comes to darkroom work, and am just about to start with PMK. I'm going shooting this weekend, and am just looking for some guidance as to preferred exposure for this developer. i.e. over or under.

I'll be developing in BTZS tubes, shooting FP4. Any help is, as always, greatly appreciated.

Paul Cocklin

Eric Woodbury
16-Apr-2007, 13:42
Page 11 refers to the fact that the total negative image as seen by the print is the silver image and the stain image. Page 45 is like a warning, Don't Underexpose. This is true.

Ideally, one exposes for the shadows and gives no more than is necessary. More exposure just adds to enlarged grain. However, underexposure is deadly. As Gordon points out, underexposure leads to muddy shadows. So, given the choice, over expose, especially if you are using a larger negative. Typically with larger negs, you don't care about grain.

As a rule of thumb, your personal film rating would be half of the manufacturer's ISO rating. For example, I rate HP5+ at 250 instead of 400. My rule for my other thumb is to place Zone IV, not II or III. I don't find the lower zones that important and I like the feel of lots of light and contrast in my 'shadows'.

Happy Shooting, --EW--

Blueberrydesk
16-Apr-2007, 15:09
Thanks for clearing that up, Eric. It's pretty much what I assumed, but it's nice to hear it from someone else. I'm enthralled by Hutchings' book; I think I've read it about a dozen times, so hopefully this weekend's foray in to the world of Pyro will work out well.

Thanks again,

Paul

Chris Strobel
16-Apr-2007, 15:29
You mention using film tubes, are you planning on using straight PMK or rollo pyro?

Blueberrydesk
16-Apr-2007, 15:39
Well, I was planning on using straight PMK, but I'm open to other suggestions and/or reasons why I should/shouldn't. I spent some time today going through the archives, and noticed that some people had problems with straight PMK in tubes, but that the Rollo gave more consistent results in terms of not streaking, etc.

What would be the benefits/detriments of either?

and thanks for any and all info you throw at me. :)

Eric Woodbury
16-Apr-2007, 16:53
I use PMK in a Jobo tank. I had problems with streaking until I purged the tank with nitrogen gas. It's a bit of a pain and I don't recommend it if you can make it work some other way. Although I now use EDTA in the PMK, I didn't at the time I was establishing this procedure. If you are somehow inhibiting the flow of developer to the back of the film, you are likely to experience some streaking. You had better figure on Rollo or tray development. I don't know if Gordon ever figured a way around this.

I developed in trays for many years, but every once in awhile I would scratch a neg. Hated that. Now I use the tank and I like the lights on approach, but I don't like having to develop one sheet of N-2 and one sheet of N+2 using the tank. With tray, I could keep track of them and pull the N-2 early.

Everybody has their own technique. Pick an easy one for you and stick with it.

Be well, EW

steve simmons
16-Apr-2007, 16:57
The silver print is exposed through the negative as usual and the light penetrates the silver density from the development and the stain which is greater in the high values. That is why the high values can have such clarity with a stained neg - you are not pushing the silver density up near or over the shoulder. This does not mean you should underexpose your film. For a simple and straight ahead way to determine film speed and dev time see the Free Articles section of the View Camera web site

www.viewcamera.com

There is also an article on staining developers in that section as well that should explain just about everything.

Gordon is also doing a session on understanding staining developers at the View Camera conference June 29-July 1 in Louisville. He is probably the most knowledgeable person working today on staining developers and has a wonderful teaching approach that demystifies just about everything he teaches.

steve simmons
publisher, view camera magazine

Chris Strobel
16-Apr-2007, 17:01
Well I've only done 8x10 with pmk.Tried it in my 8x10 tubes and got streaking.With the tray I get perfect negs every time.

Blueberrydesk
16-Apr-2007, 17:23
Thanks all, for your responses. Is the general consensus, then, that PMK may not be the best pyro developer for use in BTZS tubes for 4x5? I can always do tray development, but I kinda liked the idea of having the lights on for most of the processing.

Also, I'm always paranoid about poor agitation techique since this will be my first time doing my own developing. It's my understanding that pyro will be less forgiving in terms of agitation inconsistancies versus something like D-76. Is this true, or am I just being worrisome?

Thanks again to all. It's still amazing to me that there's a place I can go to have beginner questions like mine answered, without paying for them. :D

steve simmons
16-Apr-2007, 17:24
Put on some music and follow the procedure for tray development that I descibe in the piece in the Free Articles section. It is foolproof and has many advantages.

steve simmons

Blueberrydesk
16-Apr-2007, 17:26
:) Thanks Steve, that may be the route I take. I was trying to avoid trays due to space contraints (it's a very small bathroom) but I can make it work, if I have to.

Robert Brummitt
16-Apr-2007, 17:32
"Gordon is also doing a session on understanding staining developers at the View Camera conference June 29-July 1 in Louisville. He is probably the most knowledgeable person working today on staining developers and has a wonderful teaching approach that demystifies just about everything he teaches.

steve simmons
publisher, view camera magazine[/QUOTE]

What about John Wimberley? He after all brought pyro back and Gordon acknowledge this in his book.

steve simmons
16-Apr-2007, 17:58
True, John's W2D2 did get things started but I think Gordon's continued work in this area may make him the most well versed in staining developers.


I don't mean to minimize John's contribution in 1979 (I think that was when the Petersen's article was published). It got me started with staining developers as it was the first really user friendly formula. My point is that Gordon has been researching staining formulae and teaching their use since that time which makes him well versed in the questions that new users have in using these formulae and how to explain their function and advantages.

steve

Chris Strobel
16-Apr-2007, 19:36
Paul, its easy to do.My very first tray developed pmk neg was a success, the film tube one wasn't.At 70 degrees I do my 8x10 pmk negs in the bathtub.I use no pre-soak, just straight into the developer tray and agitate constantly for a minute, then every 15 seconds I tip the tray twice alternating sides of the tray each 15 sec. agitation cycle.The agitation movement itself being moderately vigorous.Then its a minute in a water stop tray with constant agitation, then 4 minutes in TF-4 fxer agitating every 30 seconds.Then its lights on, negative back into stop tray for a few seconds, then back into the PMK tray for 2 min agitating every 30 sec.Then the neg is put in a tray half full of water and then carried out to the kitchen sink where its placed under the faucet for 30 min.Then the tap water is dumped out, distilled water poured in along with a splash of photo-flo.A minute later I remove the neg, then its back to the tub and hung to dry from the shower curtain.Perfect neg everytime with fp-4+.If I was doing 4x5 I would use the slosher device from photographers formulary.Be sure to wear gloves of course.Also I use a digital metronome to keep time.Have fun!




Thanks all, for your responses. Is the general consensus, then, that PMK may not be the best pyro developer for use in BTZS tubes for 4x5? I can always do tray development, but I kinda liked the idea of having the lights on for most of the processing.

Also, I'm always paranoid about poor agitation techique since this will be my first time doing my own developing. It's my understanding that pyro will be less forgiving in terms of agitation inconsistancies versus something like D-76. Is this true, or am I just being worrisome?

Thanks again to all. It's still amazing to me that there's a place I can go to have beginner questions like mine answered, without paying for them. :D

Blueberrydesk
16-Apr-2007, 19:54
Chris, I'm not sure I can thank you enough for putting everything down, step by step. Know that this thread has already been printed out, and your words on paper will guide me through the morass of trials and tribulations I know I will encounter. :D

Thanks to all who responded, I now feel I have, if not a firm grasp then at least a tenuous one, with this whole process. I'll shoot some film this week, and Sat. I will develop my first PMK negs. Very exciting for me.

I guess the next step will be me asking everyone to help me with proper scanning of the negs, so I can post them here. :D

Thanks again all. If anyone has any other comments or suggestions, I'd love to hear them too.

Paul

Shen45
16-Apr-2007, 22:39
I wrote this post to the list a while back and it may be of help to you

http://www.largeformatphotography.info/forum/showthread.php?t=23371&highlight=btzs

Steve

Robert Ley
17-Apr-2007, 06:38
Chris,
I am curious as to why you put your negative back in the developer after it has already been fixed? I have never heard of this before, but I have only ever used Pyrocat HD. I can only surmise that this technique will increase the staining of the negative.

Chris Strobel
17-Apr-2007, 08:10
Hi Robert, yes the neg is put back in the used developer to enhance the stain per Gordon Hutchings recommendation.

Chris


Chris,
I am curious as to why you put your negative back in the developer after it has already been fixed? I have never heard of this before, but I have only ever used Pyrocat HD. I can only surmise that this technique will increase the staining of the negative.

Eric Rose
17-Apr-2007, 14:55
Hi Robert, yes the neg is put back in the used developer to enhance the stain per Gordon Hutchings recommendation.
Chris

Chris, I might be wrong but I don't think Gordon recommends putting the negs into the exhasted developer anymore. FWIW Sandy King's test showed it has no effect but as usual YMMV.

Chris Strobel
17-Apr-2007, 16:11
Chris, I might be wrong but I don't think Gordon recommends putting the negs into the exhasted developer anymore. FWIW Sandy King's test showed it has no effect but as usual YMMV.

Eric, I'll give it a try without and see what happens.One less step would be sweet.Would you happen to have a link to Sandy's test data?I just got off the phone with Photog Formulary and they said they still stick by the after soak, that Gordon hasn't changed the advice.Its funny though after the guy went on and on about sticking with Gordon's advice, how Gordon teaches there, been doing it for years, yada yada, He finally admitted He himself just goes straight from the fix to the wash LoL!

Chris Strobel
17-Apr-2007, 17:19
Ok, well an hour surfing over at APUG indeed it does seem no one uses an alkali after bath anymore with PMK.Supposedly Gordon says, if using non-acid T4 fix, no need to restain.So Paul skip that step :D

phil sweeney
18-Apr-2007, 05:00
I'll be developing in BTZS tubes, shooting FP4. Any help is, as always, greatly appreciated.

Paul Cocklin
Hi Paul,

for PMK in tubes additional agitation is needed, so after rolling every 15 seconds, I agitate further by turning your hands inward and grab the tubes (picking them up) and slowly but deliberately turn them up and out, back in, and out again. Return to the tray and roll. Because the PMK darkens from the agition I use 1/2 the water. That decreases time (and reducing oxidation) and also makes the developer act less compensating for FP4. I use homemade tubes and 4 ozs of developer. FYI Have fun!

Michael Kadillak
20-Apr-2007, 07:00
Hello all. I'm confused by something in Gordon Hutchings' book of Pyro that is probably just a misunderstanding on my part, but I figured I'd ask the experts.

On page 11 the statement is made that film developed in PMK should be exposed to produce "underexposed" silver density. I read this as saying that PMK does better with slightly underexposed images.

However, on page 45 under Exposing Negs for Optimum printing, it is stated that "if the shadow areas receive too little exposure, the shadows will look dark and muddy in the final print." and then goes on to state that it's not possible to get optimum values in the print if the neg has been underexposed.

I apologize to Mr. Hutchings if he takes exception to my posting a small excerpt of his wonderful book, but this part has me baffled. I'm pretty much a complete noob when it comes to darkroom work, and am just about to start with PMK. I'm going shooting this weekend, and am just looking for some guidance as to preferred exposure for this developer. i.e. over or under.

I'll be developing in BTZS tubes, shooting FP4. Any help is, as always, greatly appreciated.

Paul Cocklin

A bit off of this topic, but I wanted to post a clarification to a post that was closed by the forum moderators.

In a heated exchange a while back I made a comment concerning the amount of profit that Gordon made with his Book of Pyro. My intention was to demonstrate that in the day and age of T Grain emulsions and modern developers, Pyro is still of interest to photographers because of its unique properties. But it came across as a dig on Gordon which was completely unintentional and for that I sincerely apologize. Gordon is a first rate individual always willing to offer his assistance and the information I posted was completely inappropriate for me to bring up because it was unsubstantiated and added nothing to the post. I let the words flow before I considered the consequences and apologize to Gordon for doing so. I learned a very valuable lesson in the process.

Cheers!

Kirk Gittings
20-Apr-2007, 07:21
Thanks for making that public Michael. I know we talked about that at the time, off line, when it happened and you sincerely regretted it then.

sanking
21-Apr-2007, 14:17
Thanks for making that public Michael. I know we talked about that at the time, off line, when it happened and you sincerely regretted it then.

Kirk,

I commend Michael for his public comment on this matter. Even if the content of his original message had been true it would have been irrelevant since people should not be criticized for using their intellectual knowledge for financial gain. That is the nature of the world we all live in.

However, for some context, I think it important to understand that Michaels' comments were in large part a response to a criticism that had been made of him, by someone involved in the thread in question, of having profited financially from the TMAX-400 run that Michael helped make possible with JandC. I was involved on an informational basis almost from the beginning of these negotiations and know for a fact that Michael's only motivation in the deal was to make this film available to LF and ULF users, and I know that he spent dozens, if not hundreds, of hours in contact with various folks high in the Kodak operation to make it happen. Michael is a very successful businessman in other areas and, if making money were a concern, would and could have directed his attention to other non-photographic matters.

In any event I think it is a testimony to the character of Michael that he has apologized for something that we agree should not have been said. I think an apology is also owed Michael.

Sandy