Benefits of selenium toning negatives?

rfox9 · Jul 3, 2006

What are the benefits? I have read different info on the internet and everyone I know who shoots photos hasn't touched the darkroom in years (traditional darkroom at least).

My film is 35mm & 120 Kodak and Ilford. Properly exposed.

Any further info would be appreciated.

Thanks

Ryan

kjsphoto · Jul 3, 2006

From what I understand is to increase density in the highlights to give you a more contrasty negative while maintaining your shadow detail. If your negs are properly exposed I wouldnt suggest doign this unless you need more highlight values.

reellis67 · Jul 3, 2006

From what I've seen, the contrast boost is minimal, something like 1/4 to 1/2 grade, but the big benefit is that the life of the negative is increased by toning. You can also tone with sepia toner and get around 3/4 to 1 full grade of contrast increase as well as increased life expectancy.

- Randy

reellis67 · Jul 3, 2006

I would also add that if you want to do this, putting film on reels works best for me. I've heard it can be a bear toning roll film in trays... I put cut strips on reels and just drop them in a two-reel tank to tone for 4-5 minutes. If you have some unimportant negatives to try it with the first time, I would use those, but you shouldn't have a lot of trouble with this process. Tim Rudman covers this in his toning book, towards the back.

- Randy

David A. Goldfarb · Jul 3, 2006

You could selenium tone negatives for archival reasons, just as one does with prints. This is a standard technique with microfilm, for instance.

I usually only do it to increase contrast with a flat neg. I find I can get about a one zone boost with KRST 1:3, usually for about 8 minutes.

dancqu · Jul 4, 2006

reellis67 said:
You can also tone with sepia toner
and get around 3/4 to 1 full grade... Randy

Sepia toner as with bleach and redevelop? I've read
of sulfiding film for a big boost in contrast but did
not read as meaning the usual sepia toning. Dan

Neal · Jul 4, 2006

Dear Ryan,

There was an article on this in Photo Techniques some time in the last year. The gist of it was that the author preferred to use it to add contrast to a negative rather than as a standard processing step.

Neal Wydra

Early Riser · Jul 4, 2006

Neal said:
Dear Ryan,

There was an article on this in Photo Techniques some time in the last year. The gist of it was that the author preferred to use it to add contrast to a negative rather than as a standard processing step.

Neal Wydra

This is exactly what I do. At this point the most I will push film ordinarily is half a stop. Pushing film can make grain more obvious and is obviously impossible to monitor the change in contrast as one is doing it. I find i can get nearly an N+ 1 push by using selenium toner and have the ability to watch and control the progress. I use it 1:8 for anywhere from 1'30" to 5'. I prefer now to do this when i am processing the film. You can go back and do it to already dry negs, if you let them soak in pretty diluted fresh fix you can then tone them, however when I am getting ready to photo flo my negs I give them a quick look and if something looks like it can use more of a push I'll do it then. I feel this is safer than the whole re wet/ re dry cycle.

I also add selenium toner to my film permawash cycle, about 1:30 dilution for archival purposes, and also because i think that it's safer to tone or re tone negs that already have some selenium in them. As of yet i have never had any uneveness problems or staining of negs with this process.

RalphLambrecht · Jul 4, 2006

Randy

I use direct sulfide toning with negatives to increase their life expectancy, but I've never noticed a contrast increase with sulfide toning, and I've never heard of anyone using indirect sulfide toning on negatives. To increase contrast, I use selenium toning and get the same contrast oncrease as you suggested.

Donald Miller · Jul 4, 2006

I will chime in here and mention that the reason that selenium tends to boost the negative density range (contrast) is that the effects of selenium are proportional to density. In a print this gives a boost to the dmax of the print. In a negative this gives a proportional boost to the highlight densities.

It follows that the degree of the effect is contingent on the high value density of the negative. If for instance one had a negative that had a peak density of 1.30 and a low density of .15 the density range before toning would be 1.15 and the effects of the selenium intensification would be totally different then if one had a low density of .35 and a high density of 1.50 (again a density range of 1.15),

For many zone system practitioners, who routinely place their shadow detail on Zone III, the effects of selenium intensification will not be optimal because the negative low densities are already elevated due to a degree of over exposure beyond the film's actual speed point.

dancqu · Jul 4, 2006

RalphLambrecht said:
I use direct sulfide toning with negatives to increase
their life expectancy, but I've never noticed a contrast
increase with sulfide toning, and I've never heard of
anyone using indirect sulfide toning on negatives.
To increase contrast, I use selenium toning and
get the same contrast increase you suggested.

Some conflicting info. Selenium is so often mentioned.
A. Adams used it when he shot 120 and needed a +1
boost. Sulfide for the same purpose I'd heard of only
once before. The IPI suggests sodium sulfide at a
1:9,999 dilution for great LE with microfilm. For
contrast increase perhaps 1:999? Dan

RalphLambrecht · Jul 5, 2006

Dan

I agree, and that was my point. Selenium toning increases contrast and life; sulfide toning increases life expectancy dramatically without changing contrast. I've never heard of sulfide toning being used for increased contrast, but one post suggested for it to increase contrast beyond selenium. I did not have the same experience.

Benefits of selenium toning negatives?

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