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Joe introduces a new method for reversal processing print paper to produce direct positive prints.
Photo paper reversal processing for direct positive prints:
NOTE: Use personal protective equipment (PPE) when handling concentrated hydrogen peroxide.
Minimal recommended PPE:
Face shield:
www.grainger.com/product/COND...
Chemical Sleeve Apron:
www.grainger.com/product/COND...
Chemical Resistant Gloves:
www.grainger.com/category/che...
In-Camera Paper Exposure:
Expose grade 2 RC photo paper at ISO1.5
Reversal Processing Method:
1) Develop under red safelights for 1:30 in a 1+15 solution of dilute liquid paper developer.
2) Stop/rinse bath (water or mild vinegar) for :30.
3) Bleach 2:00-5:00 in an 18% hydrogen peroxide/citric acid solution. (For 4x5 tray processing: 150mL of 35% hydrogen peroxide diluted into 150mL water, then add 2 teaspoons citric acid powder & stir until fully dissolved.)
4) Room lights can now be turned on. Rinse under fresh water for :30. Then squeegee the front side of the print dry.
5) Fog under bright lamp at close range for 1:00.
6) Develop in same solution as step 1 for 1:00-1:30.
7) Stop/rinse bath in same solution as step 2 for :30.
8) Fix for 2:00 in paper fixer.
9) 1:00 rinse aid, then 5:00 rinse under fresh water, followed by squeegee and blow dry.