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Old 2nd February 2009, 04:20 PM
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Default Rodinal + Sodium Sulphite ?

I just came across an article in the BJP from 1999 by Bob Watkins, suggesting adding some sodium sulphite to Rodinal to improve results. I quote: "the chemistry is capable of producing extraordinarily fine negatives and outstanding print quality ... photographs show remarkable gradation, shadow detail, sharpness and fine grain while retaining the film's emulsion speed." And in his opinion "results are better than those achieved with many two-bath methods."

Has anyone tried this, and if so, did it yield a useful improvement over plain Rodinal?
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Old 2nd February 2009, 04:33 PM
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Quote:
Originally Posted by RH Designs View Post
I just came across an article in the BJP from 1999 by Bob Watkins, suggesting adding some sodium sulphite to Rodinal to improve results. I quote: "the chemistry is capable of producing extraordinarily fine negatives and outstanding print quality ... photographs show remarkable gradation, shadow detail, sharpness and fine grain while retaining the film's emulsion speed." And in his opinion "results are better than those achieved with many two-bath methods."

Has anyone tried this, and if so, did it yield a useful improvement over plain Rodinal?
Did he give any quantities or dilutions?
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Old 2nd February 2009, 04:48 PM
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Yes. Mix 30g anhydrous sodium sulphite with a small quanitity of water at 35C, then make up to 500ml. Add 5ml of Rodinal.

There are some suggested developing times as well (all at 20C):
Neopan 400 - 13min
FP4+ - 11 min
PAN F+ - 13 min
APX100 - 18 min
APX25 - 12 min
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Old 2nd February 2009, 06:25 PM
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I learned Rodinal + SS in the '70s from photographers I knew. As far as I can tell, it dates back to at least the 1960s, likely further. The number I was given was 45 g/liter sodium sulphite, which I used quite often in the late 70's through the mid 80's with Panatomic-X. The sodium sulphite's solvent activity takes the edge off the grain and softens the appearance of grain somewhat. Sodium sulphite is also a suggested additive to Edwal FG-7 for "finest grain" in the manufacturers instructions, and I wouldn't be surprised to find a connection between that suggestion and usage in Rodinal.

These days, I use Patrick Gainer's recommendation of sodium ascorbate in Rodinal at the rate of 1 gram of sodium ascorbate per 5 ml of Rodinal syrup. It gives finer grain without softening grain edges, and is wonderful with slow films. With the addition of sodium ascorbate times should be adjusted so that 1:50 with sodium ascorbate should be used at approximately the time for Rodinal 1:25 without additives.

Gainer's experiment was in a Photo Techniques magazine article called "Salt to Taste".

Lee
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Old 2nd February 2009, 07:53 PM
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Interesting Lee, thanks. Next time I put an order in to Silverprint I might try both of those. I've been a dyed in the wool Rodinal fan for many years but am always on the lookout for alternatives or improvements. The ascorbate sounds preferable perhaps as I do like Rodinal's sharp grain structure, but if I can keep that and get finer grain, that would sound ideal.
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Old 3rd February 2009, 10:50 AM
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Adding sulphite, (and/or bromide, for that matter) is the easist and most common 'tweak' for any developer, paper as well as film and can often give great results. It was going down this route in 1970 that got me interested more in the chemistry side of photography.
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Old 3rd February 2009, 04:01 PM
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I've never really done anything with raw chemicals other than mixed up some ferri bleach, so maybe it's time to investigate further.

Silverprint lists "sodium iso-ascorbate" - is this equivalent to sodium ascorbate? My A level chemistry is too long ago ...
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Old 3rd February 2009, 04:49 PM
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Yes, sodium isoascorbate and sodium ascorbate are the same. See: http://www.chemindustry.com/chemicals/972814.html for better confirmation than just my word.

I buy sodium ascorbate in the US as a powdered vitamin C supplement at local stores, not from chemistry suppliers.

Lee
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Old 3rd February 2009, 05:23 PM
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Thanks Lee
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Old 4th February 2009, 01:44 PM
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You're welcome Richard. Have fun.

Lee
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