Neopan: Best results....? Acutance/Tonality

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I am a serious amateur who has dabbled in darkroom practice off/on for the past 9 years. I now (finally) have the facilities to practice at home with the required to produce consistent results. I have tried using Ilfosol S and Tmax, and the Ifosol seems to produce nicer negs. However, in a previous message, this developer was described as a Solvent-type, which I heard dissolves some of the silver and redistributes it, reducing acutance. Is this true? Does Sodium Sulfate do this? If so, what would be some recommended developers that will yield higher acutance? Photographer's Formulary makes 2 kits called FX-1 and FX-2 that are supposed to yield highest acutance. I have some of the FX-2(for stand development) stock umixed, and am wondering about the Sodium Sulfite content. Can I use less of the S.Sulfite without penalty? Or, will a higher dilution of Ilfosol help? I don't concern myself with the appearance of grain, until it starts masking detail. I am looking for maximum acutance out of a combination that isn't too hard to print. Maybe I asked too many questions here, and should go out and get the Film Dev. Cookbook. If so, respond demanding I get the book:-), but if you can answer any questions (even one), I would greatly appreciate it.

-- Mike DeVoe (deepsixty@att.net), February 04, 2001

Answers

Oops, I suppose I should add that I've been using Ilfosol S @1:9.

-- Mike DeVoe (deepsixty@att.net), February 05, 2001.

Oops,Oops, again. Sorry. This is Neopan 400, not SS(?) or 1600. Thanks.

-- Mike DeVoe (deepsixty@att.net), February 05, 2001.

I think you really need to buy the book.

FX-2 contains a little sodium sulfite, not enough to mess with.

I'd suggest this line of experiments to see the effects of adding sodium sulfite.

Get a bottle of Rodinal and work up development specs for it for one film at a 1:50 dilution. If you don't have any idea, try HP5+ in Rodinal 1:50 7'15"/75F EI 250.

Shoot a test neg, develop and print it.

Next, do the same but add 25g sodium sulfite to a liter of working solution. The amount isn't critical; half a plastic film cannister is around 25g.

Next, do it with 50g/L.

Next, do it with 100g/L.

I'm not suggesting that you routinely add gobs of sodium sulfite to Rodinal, but that series of tests will show you exactly what happens to a high-acutance but grainy developer with the addition of sodium sulfite.

Remember, you can't get something for nothing. If you consider the characteristics of speed, grain and "real" sharpness to be a triangle, if you emphasize one of those characteristics you'll lose something in one or both the others.

-- John Hicks (jbh@magicnet.net), February 05, 2001.


Mike, Any developer that offers high acutance will accordingly show a sharp, grainy pattern. Solvent developers dissolve the edges of the individual grain particles, which lessens the appearance of grain at the expense of softening edge acutance.

Basically, there are only two types of developers: acutance and solvent. Anything you do to an acutance developer to lessen the grain prominence (adding sodium sulfite, for example), will bring it into the solvent category, so if you are going to add sodium sulfite, you might as well use D-76, for which the compromise has aready been worked out for you.

My suggestion is PMK. It truly offers the best of both worlds. It is decidedly an acutance developer, but the staining property of pyrogallo masks the grain (stain fills the gaps between the grain particles), thereby yielding an image that is extremely sharp, yet with smooth, fine grain. Many think of PMK as strictly a large format developer, but that is not so. I use it for all formats and find it incomparable, particularly with 35mm. You can use nearly any film and developer combination with 4x5 and get fine grain. 35mm is more demanding because of the small negative, and so the benefits of PMK are even more pronounced than with larger formats.

-- Ted Kaufman (writercrmp@aol.com), June 10, 2001.


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