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jetcode
30-Jul-2008, 12:07
This is similar to Robbies question but in my case the negative has plenty of meat it just happens to be mapped to a very narrow range of contrast. I want to be able to expand the contrast on the existing negative. I know Selenium can be used to increase the contrast slightly. Are there any other techniques to consider? Thanks.

Vaughn
30-Jul-2008, 12:18
A slight bleaching to reduce the shadow areas (Farmer's Reducer) -- especially if you have extra density in the shadows. The shadows will reduce at a faster rate than the highlights. Then followed by selenium toning to bump the hightlights up...which will increase faster than the shadows. I have done this with negs I have used for carbon printing with great results...don't know if there will be any detrimental effects for enlarging.

Vaughn

jetcode
30-Jul-2008, 14:44
A slight bleaching to reduce the shadow areas (Farmer's Reducer) -- especially if you have extra density in the shadows. The shadows will reduce at a faster rate than the highlights. Then followed by selenium toning to bump the hightlights up...which will increase faster than the shadows. I have done this with negs I have used for carbon printing with great results...don't know if there will be any detrimental effects for enlarging.

Vaughn

Vaughn do you visually inspect the bleaching until you are satisfied? Once the Selenium toning has taken place is the reducer no longer applicable?

Thanks,
Joe

Ole Tjugen
30-Jul-2008, 15:19
My version is bleach and redevelop too, but redevelop in a staining developer. My choise is a very short-lived soup of pyro and sodium hydrixide, one teaspoon of each in one liter of water. The "redeveloper" dies almost within seconds of mixing; but while it lasts it gives a perfect proportional stain which lets a formerly disappointingly soft negative be used for albumen prints.

jetcode
30-Jul-2008, 16:00
My version is bleach and redevelop too, but redevelop in a staining developer. My choise is a very short-lived soup of pyro and sodium hydrixide, one teaspoon of each in one liter of water. The "redeveloper" dies almost within seconds of mixing; but while it lasts it gives a perfect proportional stain which lets a formerly disappointingly soft negative be used for albumen prints.

Ole I will be scanning the negative. I'm not an ALT printer but like the results of those who are.

Ole Tjugen
31-Jul-2008, 03:47
Well, then you can scan in the blue channel which gives maximum contrast with stained negatives. ;)

jetcode
31-Jul-2008, 09:10
Well, then you can scan in the blue channel which gives maximum contrast with stained negatives. ;)

How is the stain not registered as fog during a scan? The more important question is do you know any lab that will do this kind of work since I hate to buy chemicals for a one time use? I don't even want to deal with Selenium.

Ole Tjugen
31-Jul-2008, 10:50
The stain is image-forming, not general. There is a fair bit of overall stain with the method I suggested, but the image-forming stain is much, much stronger.

I have no idea about labs. Due to a lack of good labs near here I do all my own processing - then at least I know who screwed up. ;)