Rick A
Subscriber
Welcome back David, I've missed you. I always followed your posts in the past.
I wonder if this approach would work for color film. I have a great candidate for testing - Eastman EXR 500T, over 30 years old. The film has a very massive base fog.
But I think I will have a problem with measuring the chemicals by volume - I do not have access to sodium carbonate monohydrate, only the anhydrous form, which is a very fine powder - it will have a large volume, but a small weight...
Ah, yes, but there's the question of exposure. Note what @David Lyga proposed for TMZ:
This suggests that significant overexposure is part of the approach. And that would indeed make sense, as it would boil down to a two-pronged effect:
1. Dramatic overexposure to drown out the fog
2. Minimal development to ensure only the image-wise exposure is developed while leaving the underlying fog relatively untouched
This is why I think that the same could be achieved by taking a normal developer and a very brief development time - but it would likely be an impractically short time, indeed (maybe 1-2 minutes or so). In a similar vein, one might consider taking something like D76 and dilute it 1+5 or even 1+10 while maintaining a normal development time.
The big question is whether the M:Q ratio really is so significant here. It may or may not be, and it would be interesting to test it.
Does this anti fog mix give optimum results for film and paper or is it just a way of making a bit of use of old film and paper?
I have about 500 sheets of old Agfa and Kodak paper that shows fogging, will I be able to obtain premium results with your approach?
Anyone is free to offer links to related posts if they so desire. It's unrelated to someone being a moderator.
The thread title change was the work of a moderator who (successfully) made the thread easier to identify to interested users.
Complaints about moderating should be addressed to us using the 'report' function or by sending a message to the moderator(s) involved with a link to the specific case(s) in point. General/vague hand waving is overall unproductive and I don't really appreciate it; please come talk to us - not about us. Thanks for taking this into consideration.
The sane alternative, koraks, is to get rid of the 'problem'; if that means me, so be it. - David Lyga
David, so glad to hear from you. This is great information!
Best Regards Mike
Is the small amount of Metol meant to reduce the induction period of Hydroquinone while not working superadditively?
I do not think that my method will work with color film. I have tried adding Benzotraizole and got nothing good out of it. - David Lyga
NOTA BENE TO ALL: Although my previous posts related to age-fog in B&W materials were well-thought out at the time, I do consider those writings, now, to be subordinate to those within this current post. Much experimenting has been done in the interim and, although the previous writings (concerning this specific matter) do contain still-relevant ideas, exact particulars have been modified. Honestly, I cannot foresee saying anything negative about this current post in the future, so happy am I with the results. My advice is to take my previous writings on the specific topic to be something to compare this thread with, but please allow this thread to predominate. With this (necessarily) said, I have no objection with the mods thus "illuminating" the past. Thank you. - David Lyga
This is a very helpful post David because, as we moderators have discovered over the years, when someone posts on a subject, many members go looking for other threads on the same subject. By putting your current post in context, all those interested in doing that review will be aided greatly.
Would you like us to move this NOTA BENE to the first post in the thread? We can do that if you wish.
Development progresses from the grains that received the most exposure down to those who received less (and ultimately none at all). Based on this, I find it hard at this point to determine whether your 'suppressed threshold' really is any different from just very weak development. As I said before, it would be interesting to test this by taking a regular developer and develop very briefly, and compare the results to your developer. Mind you, in both instances very liberal exposure would be necessary.NO NO NO, abbreviation of development time with normal developers gets you extremely weak negatives which cannot be effectively enlarged. You need to SUPPRESS threshold density (be it either fog or emerging image density). And when you suppress, you force more exposure to be made. - David Lyga
With a developer like this, grains do not typically go "plopp developed", it takes time. What David's developer seems to do is slow down the weakly exposed grains but give full development to strongly developed grains. A regular developer applied for short time doesn't do this: it develops weakly exposed regions a bit slower, but it also doesn't develop strongly exposed regions all that much. Look at this posting here to see the effect of severe underdevelopment.Development progresses from the grains that received the most exposure down to those who received less (and ultimately none at all). Based on this, I find it hard at this point to determine whether your 'suppressed threshold' really is any different from just very weak development. As I said before, it would be interesting to test this by taking a regular developer and develop very briefly, and compare the results to your developer. Mind you, in both instances very liberal exposure would be necessary.
Look at this posting here to see the effect of severe underdevelopment.
Forgive me for being somewhat pedantic, but at this point, that's a tautological statement unless we either have a decent theoretical explanation of why this would happen, or we have experimental data to support it.What David's developer seems to do is slow down the weakly exposed grains but give full development to strongly developed grains.
Yes that does make more sense to have this caveat up front and more readily accessible. - David Lyga
we just don't know yet whether it works, or how it works
Thanks for the answer.
I bought the film in question years ago, not because I needed it for something, but simply because it was cheap. In fact, the shipping cost more. And that's for 400 feet. But it seems that the seller actually knew exactly what he was selling.
My first attempts with this film were... disappointing. With normal development, the base was almost black, extremely dense. It was very difficult to distinguish whether there was an image at all or the film had been fully exposed to light. But it's not. It was just poorly stored for decades.
Some time ago, I had made several attempts with it - pre-bleaching. I loaded a piece of film into Jobo, first bath - removing the remjet, second bath - rehalogenating bleach. Intensive washing and soaking in alcohol, taking it out and drying - in absolute darkness. Then in the camera, a walk, photos and normal processing. And the big surprise - the base was CLEAN - like on a new film, with a nice mask. Unfortunately, in the rush of shooting I forgot to set the light meter - instead of 6-12 ISO, I shot it as 320. Too optimistic, but hey, THERE WAS COLOR!
Sorry for the deviation, but let me mention my idea, looking at this topic:
- overexposure 5-6 stops;
- developing as black and white, according to your scheme, with maximum suppression of the base fog. Full process - developer, fixer, washing and drying;
- analysis of the result - if necessary, repeat with corrections;
- if we have a clear image and an acceptable base, we proceed to color:
1. water bath - 15 min;
2. rehalogenating bleach. I can add a little ammonium bromide;
3. reexposure;
4. color developer. Can be double strength or with an extended time;
5. bleach;
6. fixing;
7. washing and drying.
With a developer like this, grains do not typically go "plopp developed", it takes time. What David's developer seems to do is slow down the weakly exposed grains but give full development to strongly developed grains. A regular developer applied for short time doesn't do this: it develops weakly exposed regions a bit slower, but it also doesn't develop strongly exposed regions all that much. Look at this posting here to see the effect of severe underdevelopment.
Looking at David's developer I see a blend of "speed losing high contrast HQ only dev" with "regular Metol based developer". HQ only may be too inactive in the weakly exposed but still image relevant areas, so a small addition of "regular dev" seems to reach the sweat spot.
Development progresses from the grains that received the most exposure down to those who received less (and ultimately none at all). Based on this, I find it hard at this point to determine whether your 'suppressed threshold' really is any different from just very weak development. As I said before, it would be interesting to test this by taking a regular developer and develop very briefly, and compare the results to your developer. Mind you, in both instances very liberal exposure would be necessary.
That seems to match very well with what I said:
View attachment 397073
The red line would be representative to what I propose.
Of course, the plot above does not contain a curve that represents David's approach.
Forgive me for being somewhat pedantic, but at this point, that's a tautological statement unless we either have a decent theoretical explanation of why this would happen, or we have experimental data to support it.
For clarity, I'm not saying the theory is wrong - we just don't know yet whether it works, or how it works.
Your theory is rather sound but the pragmatic aspect fails.
my endless experimentations posit otherwise
Well, as I said, it would have to be tested. You posit a hypothesis, we could now try to figure out whether it is indeed as deterministic as it seems at first glance, and if so, how it might work. Or we could take it at face value. For me, personally, it's kind of a moot point since I don't have much expired film or paper to work with and my interests are in other areas. From a hypothetical viewpoint, it's amusing to think about, that's all. It's not about homage etc. at all for me, just curiosity.
So did you do the A/B testing of a regular developer with a very short development time (or a regular developer diluted way down) vs. your special-purpose developer? What kind of sensitometric or visual differences did that yield? Just to keep this clear - I don't doubt your approach works. I'm curious as to how it works, i.e. what the underlying mechanism would be. Perhaps someone with more knowledge about the theoretical aspects of developers could chime in; maybe @Lachlan Young?
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