who is adding ascorbate(c vitamin) in developers,with what results?Last photo-techniques shows spectacular pictures about it:developments done with Rodinal and done with Rodinal+ascorbate inthis way grain is very very reduced.sorry for my english i am french

-- jean (jeantollio@hotmail.fr), January 02, 2002

Answers

I'm sure that Linus Pauling would have loved to hear that!

-- John Chan (ouroboros_2001@yahoo.com), January 02, 2002.

John,

Good one.

Jean,

I'm going to try it.

-- sam smith (Ruy_Lopez@hotmail.com), January 02, 2002.

Ha, ha, John :-)) !! The best I've seen for a long while ! !

-Iván

-- Iván Barrientos M (ingenieria@simltda.tie.cl), January 02, 2002.

Photo-techniques is the name of a very serious american magazine ,buy it and look at vitamine C pictures,will be surprised;yvan it is not a joke

-- jean (jeantollio@hotmail.fr), January 03, 2002.

I've run a few tests of a couple of films in Rodinal 1:100 with sodium ascorbate added at the rate of 4g/L working solution, compared with plain Rodinal 1:100 and Rodinal 1:100 w/20g/L sodium sulfite.

TMX and Acros were essentially unchanged in character; curve shape was unchanged from Rodinal 1:100 while the EI of each was down by 1/3 stop. No significant difference in sharpness or graininess could be seen at 30x.

HP5+ was somewhat different. Curve shape and EI were the same for Rodinal w/ascorbate and Rodinal w/sulfite, both these were 2/3 stop faster than Rodinal with no additive. The Rodinal w/ascorbate negs showed the finest grain of the bunch, perhaps finer than Rodinal with 50g/L sulfite, with no decrease in apparent sharpness. Note that the differences are rather subtle; it doesn't approach the fineness of grain of D-76 1:1 or 1:3, for example.

It's important to use the right kind of "vitamin C;" one person used plain ascorbic acid and got blank negs because of its acidity. I used sodium ascorbate, stated pH 7.1.

This doesn't turn Rodinal into a fine-grain developer but it may make the difference of whether or not you'd want to use it with fast film in 35mm.

-- John Hicks (jhicks31@bellsouth.net), January 03, 2002.

Jean, just a note since some of the answers to your question involve the vitamin-fame of ascorbic acid. I haven't done any developing yet, but ascorbic acid being an organic compound results in its instability as a developer. Most developers are oxidizing agents and/or instable substances. But ascorbic acid is more of a reducing agent and thus (in your case) may instead have a function as a fixer like many inorganic acid's salts such as thiosulfites etc. These are much more stable than the above-mentioned organic developers, and in any case more stable than ascorbic acid.

-- Michael Kastner (kastner@zedat.fu-berlin.de), January 03, 2002.

Jean, I've tried Rodinal with ascorbic acid and got mixed results.
The best results I get with "vitamin C" developers is using XTOL 1:1; the secret is to pre-wet, reduce agitation and increase time. I get accutance comparable to that of Rodinal, fine grain and no loss of speed. I use TriX and TMax 100 or 400. Hope this helps.

-- Roger Marques (roger@photo.net), January 03, 2002.

Hi, Jean:

Please excuse my attitude if you understood I was laughing at your posting. Far from it: I truly admire people who do their own darkroom work, something I still have left to get into but just began trying thanks to Lutz's good will.

What I found funny (and still think so) was John's reference to Mr. Pauling. In a photo forum his image seems (to me)so far away from "normal" context that I couldn't help smiling as soon I saw it...

I insist I didn't intend any ofense, Jean. Excuse for interfering with your posting. And have a wonderful 2002 along with your loved people ! !

-Iván

-- Iván Barrientos M (ingenieria@simltda.tie.cl), January 03, 2002.

yvan dont worry about about your mail ,the first time i see something about pauling developers i think it was bullshit

-- jean (jeantollio@hotmail.fr), January 04, 2002.