Push Processing (B/W)
These are general guidelines when no published development times are available. To use this chart multiply the published time at recommended ASA by the factor in parenthesis (ie. If Tri-X rated at 400ASA is normally developed for 6 mins in a standard soup, then when Tri-X is pushed three stops to 3200ASA development would be: 6 x 4.5 = 27 mins). Please use these recommendations as starting points only. In many cases these times will prove excessive, but when all else fails they can be a good guideline. Please note separate data for Tmax films.
- Standard Developer
- 1 stop push = (x1.5)
- 2 stop push = (x2.25)
- 3 stop push = (x4.5)
- Compensating Developer
- 1 stop push = (x1.4)
- 2 stop push = (x1.85)
- 3 stop push = (x2.5)
- TMax Films
- 1 stop push = no change
- 2 stop push = (x1.33)
- 3 stop push = (x1.66)
*Compensating developers include Microphen, TMax, and any other developers which are specifically formulated for push processing