Developing 400ASA film to 100ASA - Atomal FF dev.

I recently wanted to pull some 400ASA film (mixture of HP5+ and Delta400) a couple of stops. The problem with pull development is that manipulations with a standard developer (eg D76 and using shorter dev. times) does more to decrease gamma rather than the real speed of the film.

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I tried Agfa's Atomal FF developer, as this was recommended to me, but with less than positive results. Grain and sharpness we not significantly better than these films would produce with dev to normal speeds (at least to my eye, though others may have a different opinion), and certainly no where near as good as Delta 100 or FP4+.

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Does anyone have an opinion or comment on ways to get decent negs (ie normal contrast, say 0.55 or 0.6, and withoug destroying sharpness) when pulling a film by up to 2 stops, and any comments on the Atomal FF developer? Are there any home brews that are good for pull development?

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Thanks

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George

No comments on Atomal FF, but if you want a real gain in speed rather

than in gamma, your best bet might be a two-bath developer, such as

Tetenal Emofin. This is said to produce about a one-stop increase in

actual speed.

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Regards,

Thomas Wollstein

Don't know about Atomal. I remember David Kachel referred to

something about speedwise bleaching (the Sterry method?) as the way

to get a true decrease in speed i.e., without affecting contrast. If

memory serves me right, he talked of a pottasium dichromate and acid

bath being used as a bleach. Let me know if you are interested and

I'll try to dig out the references. I guess an off the shelf approach

would be to develop normally and use a cutting reducer like Farmer's.

Cheers, DJ.

Microdol-X or Perceptol undiluted will drop film speed about a stop.

At any rate overexposing silver image B&W film will increase grain

and reduce sharpness. No way around it. Why fight the film's natural

characteristic?

It seems to me that you are asking if there is a developer that can

give normal gamma and contrast to film that has been overexposed by

two stops. You do NOT wish to do an N-2 development? I am not aware

of a developer that can do this.

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The Sterry method mentioned above is a means of reducing contrast

without loss of film speed by bleaching the film prior to

development. I have an article on it entitled "Latent Image

Bleaching" on my site at <a

href="http://unblinkingeye.com/Articles/LatentImageBleach/latentimageb

leach.html">http://unblinkingeye.com/Articles/LatentImageBleach/latent

imagebleach.html</a>. But I don't think it is the answer you are

looking for.

Ed, the Sterry method actually encompasses two methods - contrawise

and speedwise bleaching. Contrawise bleaching does what you suggest

i.e., alter contrast without altering speed, while speedwise

bleaching alters speed without altering contrast. I should add that

this is what I remember from Kachel's article in DCCT - I've never

done any speedwise bleaching myself. Cheers, DJ.