Sodium bisulfite, HP-5 and grain

normmamiya

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Hi everybody

I read somewhere that a small amount of sodium bisulfite solution (9%) reduce
grain. Is it true? I want to try it with HC-110 with HP-5 (800 ISO) or Delta 3200. Any comments or recipies?

Regards
 

gainer

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Except minimum correct exposure and minimum necessary development. But you knew that, Roger.
 

Photo Engineer

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Minimum correct exposure (slight underexposure) is worse than slight overexposure from a grain standpoint.

Which is saying, to reduce grain, you must reduce speed.

PE
 

gainer

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Photo Engineer said:
Minimum correct exposure (slight underexposure) is worse than slight overexposure from a grain standpoint.

Which is saying, to reduce grain, you must reduce speed.

PE
Click to expand...

But then it is not minimum correct exposure. I set exposure for 4 times box in the shadow where I want detail. I don't think that is underexposure, unless my meter is not calibrated right.
 

Photo Engineer

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I always refer to 'minimum' as slight under exposure Patrick. Sorry for the confusion. Minimum is actually the lowest exposure on the straight line portion of the curve.

PE
 

Roger Hicks

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Photo Engineer said:
I always refer to 'minimum' as slight under exposure Patrick. Sorry for the confusion. Minimum is actually the lowest exposure on the straight line portion of the curve.

PE
Click to expand...

Dear PE,

I'm inclined to regard 'minimum' as 'the least you can get away with and still like the tonality'. At this point, of course, we're getting into fractional gradients -- yet another underrated Kodak analysis, even if the 'first excellent prints' weren't all that excellent.

I've not seen them, but I'm told they're rather flat 5x7 inch contact prints. Any further comments on that description?

Cheers,

R.
 

dancqu

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normmamiya said:
Hi everybody: I read somewhere that a small
amount of sodium bisulfite solution (9%) reduce
grain. Any comments or recipies? Regards
Click to expand...

All things being equal save for ph, the lower
the ph the less is the grain. I believe D-25
and Microdol X are good examples of low
ph very fine grain developers. A speed
hit is likely. Dan
 

Photo Engineer

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Roger;

As you go onto the toe, all prints become flat and lifeless and rather grainy. These are underexposed.

A print is really the intgral, point by point of the product of two curves, the film and the paper. If you are on a straight line, then one is a constant (the film) and the other is mostly a constant (the paper) except for the toe and shoulder.

This is a lossy process like JPG image compression, and gives a blah looking print.

Thats why I always stay off the toe and try to stay on the high part of the straight line, where I'm using the finest grains in the film, and also where the fill in of the developing silver reduces grain even further.

So, I overexpose to get better contrast and less loss. Or at least, I lessen the chance of it happening.

PE
 

gainer

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As long as one knows what he is doing and likes the results, I don't think I should care. What I do not like is the statement "I use ISO xxx" as if admonishing me to use ISO xxx, unaccompanied by the actual statement of how ISOxxx was used. I have griped about this before and present company was not the object of any of my gripes. It is always helpful to do as philosophers are supposed to do and define one's terms.

I must say I am not fond of developers that require me to move up the curve. If I am looking for finer grain, I would rather use slower film. I think with the developers I know and use, my exposure method used on a normal SBR will give about the same shadows as an incident light reading. It has the advantage in wide range scenes of giving the same shadows. There is not much point in cutting the development of wide range scenes in most cases because the print will have to be dodged and/or burned any way as painters do. I think Ansel Adams resorted to this technique when he used the roll film and could not develop each exposure individually.

Note the the shadow point can be somewhere other than 2 stops from the ISO, according to taste. The pictures I made that most profited from this approach were taken at rehearsal from my chair as first oboist. Stage lighting can cause the auto exposure system to give different readings when the scene includes more or less of a music stand. That is the highlight and is the same everywhere, as are the significant shadows. I soon figured that i should use the same exposure for any stage scene and the same development for all 36 exposures.
 

Jordan

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The usual agent added is sodium sulfite, not sodium bisulfite. The former may raise the pH of your working solution, while the latter may lower it. These pH changes can be difficult to disentangle from the effects of the grain-dissolving agent.
 

gainer

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HP-5 and grain.

dancqu said:
Sodium bicarbonate should do. Little enough alkaline,
I'd think, to lower HC-110's ph. Dan
Click to expand...

I understand your words, but not your sentences. (I used to get that a lot from the branch head). Would you add carbonate to change the pH change of bisulfite? Then you would have sulfite and fizz, no?
 

dancqu

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gainer said:
Would you add carbonate to change
the pH change of bisulfite?
Click to expand...

Not at all. Jordan mentioned that addition of bisulfite is
just more sulfite although the developer is at a lower ph.
So, is it more sulfite and/or the lower ph which makes for
the finer grain? To avoid the question I suggested sodium
bicarbonate rather than bisulfite be added. Dan
 

gainer

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OOPS! Didn't see the bi. Now I know I'm getting old. Now it makes logical sense, but I wouldn't know without pH measurement how much does what in which developer. That wouldn't keep me from trying if I thought I needed it, though, as you have probably noticed.

Sulfite is pretty tricky stuff. I haven't got much out of using a lot of it in Rodinal working solution other some than loss of resolution which for me takes the fun out of any finer grain that might happen. Another way to reduce pH would be to add a very small amount of ascorbic acid.

I'm not trying to make a whole lot of sense. I just had a pain that was, I think, a gall stone but might have been a kidney stone. It was one of those pains that make you afraid you will die, then afraid you won't.
 

eddym

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Very true; I learned this many years ago, when I began shooting ballet and theater. Auto exposure, matrix metering, etc., is useless. I use a handheld spot meter and read the highlights, placing them on Zone VII or XIII, as needed. It's based on Fred Picker's Zone VIII metering method.
 
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