PDA

View Full Version : Paper Negative Reversal Process



Pages : 1 2 [3]

Alessandro Serrao
04-25-2013, 05:43 AM
You will need Dektol, Sodium Hypo, Potassium Dichromate, Sulfuric Acid, Hardening fixer, and Sodium Sulfite.

Process:

Dektol 1:2 or 1:3 for 1 - 3 minutes DBI..
clear in Sodium Sulfite bath (about 20 g/L) 1 min
Wash 1 - 2 mins.
Bleach in Dichromate + Sulfuric acid (formulas all over APUG and elsewhere for this)
clear in above clear about 1 min
Wash 5 mins
Turn on the lights and FOG the paper front and back.
Dektol again but with 500 mg /l of Sodium Hypo, DBI again.
Stop
Hardening fix
Wash

This should work. There are many many alternates for the bleach and the redeveloper.

PE

Hi PE,
I was wondering why the silver halide solvent is in the second dev instead of the first one.

Photo Engineer
04-25-2013, 12:05 PM
My search showed SCN in the FD or the SD or both. My opinion, after looking at a lot of data says it is best in the FD, but don't discount use in the SD.

PE

andy_k
04-28-2013, 04:13 PM
hey PE, can you make any comment on what you think is going on in the solarization process, or point me toward some academic/scientific studies on the phenomenon? i'd like to do more than guess at precisely what it is that i was doing there.

for a progress update on the project to make a bigger camera for the purposes of this process, attempts to this point have been abortive. i shall endeavor to resolve this in the coming week.

andy_k
05-22-2013, 02:28 PM
so, small update. i built a pinhole camera to take fullsize photos and did some work yesterday with 11x14" paper. results were... not ideal. the long exposure times really hinder getting adequate feedback, and i was really panicked to get the work done on a schedule. this means that my poor results with the process were probably exacerbated, but at the best of times it can be a little unpredicatable (particularly when i'm relying on my hand to do reliable timing on the second exposure).

no time to post results, not that they are good anyway, but just wanted to mention that i was still working on it.

andy_k
06-09-2013, 09:47 AM
goddamn, is that panchromatic B&W paper? with an IDmax of 2.3 without toning? ffffff.... WHY ARE YOU USING GOOD PAPER FOR SCREWING AROUND??!!
also, i meter my paper at EI 25 and use a super high concentrated developer for my "controlled" solarization reversal.