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TWEEN 20 - PHOTO FLOW

A"POLLY SORBATE 20"

50% STANDARD FROM BOSTICK & SULLIVAN I use TWEEN 20 in many dilutions from 50% down to 5% The strength depends on what paper you are using. Some papers like TWEEN others hate it. With Archers Platine be carful with TWEEN most often TWEEN causes problems with this paper. To make working solutions add drops of 50% tween to distilled H2O.

DROPS WORKING SOL. OF TWEEN 20 IN ADDITION TO STANDARD EMULSION!

Below is a starting guide that we use in my darkroom:

You should try using tween 20 at any dilution you want but I have found that at heavier concentrations you run into a problem with developer stain. This may be due to how hot my developer is. On some prints with very large black areas I do use it at 50% to help get very smooth deep blacks but I am very careful in putting the print in the developer. Also the developer seems to eat up the tween 20 so the staining problem tends to remain(with that developer) even after you go back to a weaker dilution in your emulsion mix.

Tween 20 works much better than photo flo! And solves a lot more problems, but....
1 drop of photo flo to 30 mls. of distilled water then add 1 drop of this solution to your emulsion mix to help coat smoother. You may need to increase total amount of solution as this will make paper absorb more liquid.

If you have trouble with blacks "floating" off paper during development and staining your whites after drying then try adding 10 % ethel alcohol to the emulsion mix before coating. This may help emulsion to sink into paper. For some reason it seems to also increase the speed of the paper so you need less exposure time. This problem may be due to too much moisture in your paper- try putting your paper in a dry mount press or dry with before you coat the paper.

This floating problem can also be caused by too much #3 (metal in your mixture! If you reduce the amount of metal you will have to reduce exposure or bronzing may result.