Controlling contrast in B&W film

GregY

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dcy said:
Las Cruces -- 4 hours from Santa Fe.
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When you have time... it's well worth the trip. There are exceptional prints in the Georgia O'Keefe Museum. (including Steiglitz & Adams).
I don't know what's on at the New Mexico Museum of Art....but I've seen wonderful work there. If you do make it..... also check out the William Clift Gallery. W Clift is a tremendous photographer & printer.
Seeing fine optical prints ....can be inspiring.
 
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MattKing

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dcy said:
I've never actually seen a real-world optical print except for my own beginner attempts.
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Contact the folks at the Las Cuces Museum that maintain this collection: http://5089.sydneyplus.com/final/portal.aspx?lang=en-US&g_AABX={s:AAAI}&d=d

There appears to be a wide variety of photos there whose main value will be historical, but it is likely that there are original prints amongst them that will be of high quality.
For clarity - don't just look at the digitized versions. Arrange to go see them in real life, if you can.
As an example, the digital version of this one is pretty good, so the original may be a good example:


The curators with responsibility for them may also be able to refer you to others.
 

Sirius Glass

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For black & white films the contrast can be controlled by using color contrast filters such as yellow, orange, green, blue, red and polarizer filters.
 
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dcy

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I'm going to ask a dumb question. Thank you for being patient with me:

If I'm going to use D-23 at 1+1 dilution, should I add 10-15% to the time for D-76 stock or D-76 at 1+1 dilution? I'm guessing it's the latter, but I'd rather ask than lose a roll.

For now I'm going to use all developers "one shot" to remove one source of complexity.
 

mshchem

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Now we need to discuss contact printing large format negatives on print out paper (POP) followed by toning with gold chloride.

Yikes. D23 sounds like a better next step.
 

Milpool

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mshchem said:
Now we need to discuss contact printing large format negatives on print out paper (POP) followed by toning with gold chloride.

Yikes. D23 sounds like a better next step.
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Yikes it right. This has all turned into exactly the kind of thing OP should be avoiding. It never fails.
 

Yezishu

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Ah, as there are road signs pointing the way back (standard combinations tested by manufacturers), the worst risk is just that the homemade soup might not perform well on the samples.

D-23 is simple enough and it shouldn't cause any issues... Phenidone based formuler is also convenient as they only need a pinch, and pharmacies always have an unlimited supply of ascorbic acid.
 

GregY

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mshchem said:
Now we need to discuss contact printing large format negatives on print out paper (POP) followed by toning with gold chloride.

Yikes. D23 sounds like a better next step.
Click to expand...

You say that like it's a bad thing....
 
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dcy

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Yezishu said:
The second is Martin Levy's POTA formula: 30g anhydrous sodium sulfite, 1.5g phenidone, diluted to 1L.

... while POTA is a very low-contrast developer that requires long development times (and degrades quickly, intended for one-time use).
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Alright. I've been reading about POTA and I think I'm up to speed.

It's an interesting, but definitely unusual developer. Shelf life of 1 hour, and most often associated with trying to use super high contrast technical films like Kodak Technical Pan for regular photography.

I've put a mental pin on the idea. I have a document where I keep notes and I added an entry about POTA with the recipe so I don't forget what I've learned. For the time being, I'm going to focus on "normal" developers. I can try POTA any time that I'm feeling adventurous.
 

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POTA is a developer you don’t use for “normal” films - it’s designed specifically for creating “pictorial contrast” negatives with very slow “copy” films - films that were not designed with a gradual, straight line curve, as are most of the films photographers use. POTA is something you’d use to manipulate a copy type film to behave in a way that it’s not inherently designed to do: it’s an exotic outlier with a very specific use case. For pictorial work, Adox CMS 20 II is one film in this class for which POTA is a good option.

I can see that you’re curious about photo chemistry and the “fringe” developers and techniques. That’s great, but I urge you to “learn to walk before you run” - ie: don’t be seduced by the exotic outliers when there’s so much to be learned within the realm of “normal” processes.
As I mentioned earlier, you’ll probably find Troop and Anschell’s cookbook on film developers fascinating and very educational, so get yourself a copy - you’ll be glad you did. It will answer a lot of questions you have now, and loads of questions you didn’t yet know you had!
 

pentaxuser

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I think the above and in this I include Alex Benjamin's advice in your #79 is all you need to follow for the time being. I feel you will be pleasantly surprised at the results

pentaxuser
 

Milpool

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POTA was formulated by Levy in an attempt to get as wide an exposure range as possible out of the emulsions of the day. It’s not a developer OP should bother messing with.

I agree partially with the advice above from Retina Restoration - up until the walk before you run part which can give one the impression say D-76 or Rodinal are things for beginners which should be learnt before moving on to the fancy, more sophisticated (or worse, “better”) stuff for the big boys. Really, really, very much the wrong interpretation.
 

retina_restoration

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My opinion is just one among many. Feel free to ignore that "advice".

I don't typically say that sort of thing to anyone, but the OP seemed to be a bit too eager to wander into the Land Of The Exotics, for no sound reason other than his fascination with the chemistry of B&W developing. As you yourself have just pointed out, POTA is a special purpose developer that is not something "OP should bother messing with", so all I intended was to suggest that OP spend more of his time and energy learning the essential aspects of B&W film processing and spend less chasing after the sophisticated stuff. Surely that's not bad advice?
 

GregY

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RR, "walk before you run", "jack of all trades, master of none" are fairly universal points of view & commonly accepted in many trades/crafts. They seem to me to be pretty reasonable advice for someone with enthusiasm who's yet to see a professional optical print....
 

GregY

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MP that's very much your interpretation....nowhere does RR imply that normal processes are inferior, or for beginners....
 
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dcy

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I think that, at least in this instance, you have the story backwards. I did not come to this forum to ask about POTA. A member of this forum suggested that I might be interested and I wanted to be respectful enough to at least look into it. I did that, I let @Yezishu know that I had done so, showed appreciation, and reported that I will put that idea on hold for the time while I stick to normal developers.

EDIT: Every developer that has been discussed in this thread was introduced by someone who is not me. My initial question was about film contrast. Guys! Please understand that I'm trying to find a balance between being respectful to all the people who are coming in to suggest other developers, while trying to not end up with a dozen new developers in my Darkroom.
 
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Craig

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I have used POTA once, with Technical Pan film as a way to tame it's inherent contrast. It would not work well with regular pictorial film.
 

chuckroast

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GregY said:
MP that's very much your interpretation....nowhere does RR imply that normal processes are inferior, or for beginners....
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I'd suggest that there are several conflicting realities here:

On the one hand, manufacturers are trying to balance shadow speed and highlight speed for each specified film/dev combo so that most people, most of the time, in most lighting circumstances to ... mostly give decent results. Particularly when film was the only game in town, companies like Kodak were maniacal in producing repeatably good outcomes with their films, chemistry and recommendations.

On the other hand, because shadows develop much more slowly than highlight, getting full shadow speed while not blowing out the highlights typically requires some of ... what did someone call it ... "esoteric" methods. They are not any such thing, of course, they are just less frequently used methods because they are (or can be) fiddly to get right. Among them are divided two bath development, SLIMT, (semi) stand, and Extereme Minimal Agitation.

The other thing is that the enthusiastic newcomer will see all these choices and want to try everything on the menu because ... it's just plain fun. We've all been there are some point or another. I would never want to discourage exploration by someone new to all this - there is great joy in it. (I fear that some of the commentary here has been unduly strong and could be read as discouraging.)

But, as I have said previously on many occasions to many people, you have to master one film, one developer, and one standard development scheme or those various wandering will be so distracting that one can never really learn to exploit film and printing properly. Personally, it took 40 years of conventional, then Zone techniques before I was remotely ready to tackle semistand and EMA. SLIMT is next because ... exploring is fun.
 

snusmumriken

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@dcy, those of us here who are getting on in years have been where you are now and can remember it well! You read about all the things to avoid (contrast, grain, thin negatives, dense negatives, bromide drag, muddiness, …) and assuredly you will encounter some/most/all of these over time. But the crucial point is that you can’t have everything at once, you have to compromise one thing to get another. So what I want to advise is to stop worrying about problems that haven’t arisen yet. Get going with one common film and one common developer, and after a while (eg a year!) ask yourself what you don’t like about your photographs. That’s the time to wonder what to change.
 
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dcy

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I would like to add another response to no one in particular.

My initial question was about whether "film contrast" is arbitrary.

The thread initially is about contrast, but later moves to film stocks.

I respond to one of the comments about film stock and say I have Fomapan 400 and plan to develop it with D76.

The response I get is that D76 is fine but I might want to try D23. Then another member agrees that Foma 400 can indeed look great in D23. I reason that these people know far more than I do, so I take the advice seriously. I look into D23 and decide to give it a try.

Then another member says that, with the stuff I have at home, I could make this thing called POTA and says some interesting things about it.

Then another member recommends that I buy what I need to make D-76 and MyTol at home.

Eventually I catch up with the POTA comment. I reason that this person knows far more than I do. I look into POTA. Decide it's too specialized. I politely reply that I looked into it, made some notes, but will not explore it at this time.

Then the guy who recommended that I make MyTol at home urges me to stop getting seduced by exotic developers and at-home photo chemistry.



Looking back, it's actually kinda funny.
 

Yezishu

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I don't think anyone here is suggesting that the OP should start directly with POTA, and the OP doesn't think so either.

In another thread, most of the advice given to the OP was to use official D-76 and development parameters to achieve stable and good results, which the OP also plans to do. This is the context for the discussion: we all agree that it's crucial to be familiar with a standard method first. From there, one can consider other commonly used methods, such as PCTEA and slightly different ones like D-23.

Only when there are further needs (in here, to control contrast when standard method plus adjustment in printing or scanning not work) should we consider more unconventional methods, which can handle specific situations but are not generally 'better'—otherwise, every commercial company would offer a corresponding product! Examples include variants of PCTEA, and finally, specialized solutions like POTA. That is what I say, and I believe the OP know it and just see it as more introduction for fun.
 
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