NEGATIVE REDUCTION

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Since you generally make a print slightly dark when intending to sepia tone because there is some image loss in the bleaching/redevelopment process, can the same logic be applied to overly dense negatives? In other words, will bleaching a dense negative in sepia part A bleach then redeveloping in part B produce a more printable negative? Or should the redevelopment be done in a film developer?

-- ricardo (ricardospanks@yahoo.com), May 16, 2002

Answers

If this is the only negative, that is, this is not something you want to apply frequently in your image-making activity, forget about it and just deal with dense negative, especially if this particular dense neg is important.

I don't think sepia toning helps to reduce negative density. (It may reduce the refrective density) Furthermore, I think that sulfide solution can very well stain negative's gelatin layer. (By the way, selenium toner is clean working with negative and also very useful as an intensifier)

If negative reduction is something you are interested anyway, I recommend you do some serious library research on it. While doing library research, expose another or two rolls with gross overexposure, and process as if you underexposed. Try every technique on these first. You want to choose one of those classified as "proportional reducer" because you are interested in reducing dense area rather than light areas. If you need to use your ferricyanide bleach, dilute a lot may help. Then partially bleach to the point you like, rinse in plain water, and bring it to your regular film fixer solution. (If you want to start over, redevelop the negative in a regular developer. But reduce very slowly to avoid the risk of over-reducing from the beginning.)

-- Ryuji Suzuki (rsuzuki@rs.cncdsl.com), May 16, 2002.


Ricardo, even if you succeed to tone your negs in sepia toner (I have never tried it, so I don't know if it works) the result will be some brown - reddish negatives. Since the B+W papes are insensitive to red, you shall only succeed to augment instead of diminishing your exposure times. Blue toner would be more logical. Why not trying to bleach and redevelop in a soft, diluted developer to see what happens ? Try it with an unimportant neg to see the result...

-- George Papantoniou (papanton@hol.gr), May 16, 2002.

The color you see from sepia toning comes from a different mechanism compared to tanning of the gelatin layer, and it will look as shadow to paper, making no or little difference. In addition, sepia toner doesn't make most films (bromide and iodide rich emulsion) look warm brown as it would many papers.

I recommend against blue toners as they are very not archival (unstable metallic compounds are used, such as iron).

-- Ryuji Suzuki (rsuzuki@rs.cncdsl.com), May 16, 2002.


Ricardo, the sepia toning kit will help reduce the negative density and tone the negative if you want. So lets go by steps, first the bleaching part of the sepia toning is what is known as part A of the Farmers reducer. This is only pure potassium ferricyanide. If you wish to bleach a negative and then redevelop this is what you use, if you wish to bleach it and make the reduction permanent then you place it on fixer after you have reduced. As to the toning effect, yes it will change the color of the negative if you use the sulfide part, lets examine the process, on paper you have paper support, gelatin and silver salts on a negative you have plastic support, gelatin and silver salts, so asyou can see the toning effect will occur on both negative and paper. Now if you wish to have a color on your negatives it is easier to use a tanning developer, like catechol or pyro rather than sepia toning your negatives. BTW there is no such thing as refrective density and iron porocesses like cyanotype and Kallitipe are some of the most stable and durable processes. If you wish to tone your negative blue go ahead, it will last longer than you or I will.

-- Jorge Gasteazoro (rossorabbit@hotmail.com), May 18, 2002.

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