View Full Version : Interpositive advice

17-Jun-2015, 07:16
Greetings. I am trying to make 4x5 black and white interpositives from 4x5 negatives to use for wet plate collodion work. I understand the process but am not getting usable results yet. I have tried the Ilford ortho film as well as T-max 100. I made contact prints at different exposure times. I tried developing in d76 and dektol and keep getting very flat cloudy results no matter what I try. I would appreciate any advice on how to make a decent Interpositive for wet plate printing.


Joe O'Hara
21-Jun-2015, 05:07
It's hard to say what the problem might be without more information.
Does the negative print well on silver gelatin paper?
If you're making the interpositive on TMAX, are you certain that you're
not fogging it during exposure or development?
There's no chance you've got the interpositive film emulsion side down
(away from the negative) when you're exposing it, right? And you don't
have any diffuser film between the negative and the film, correct?
As a point of reference, when I make interpositives on Arista lith film,
using my enlarger as a light source, I can make continuous tone images
with exposures in the 10 second range, developed in Dektol 1:10.
Good luck!

Jim Jones
21-Jun-2015, 17:35
The original negative has less contrast than the subject. Using typical film for the diapositive further reduces contrast. A high contrast film like the old Kodak Tech Pan will provide more contrast in diapositives.

Drew Wiley
22-Jun-2015, 12:34
TMX should work just fine if you dial it in right. The best developer for a long high contrast straight line would be TMax-RS developer full-strength. My second choice would be HC-110. Yeah, Tech Pan can be made to work, if you can still find any. Ortho litho would be only a low budget choice, and with Dektol can risk
uneven development and fogging. FP4-Plus is also a decent interpositive film, but not amenable to quite as high a contrast as TMX or TMY.

24-Jun-2015, 19:52
Negative is good. Very easy to print on paper. When I made the inter positive I contact printed emulsion to emulsion. Thank you all for the advice.
I have had to put off further tests due to some other printing needed right away. I will try again soon and see if I can tweak the process.