From: Steven Budden (email suppressed)
Date: Fri Mar 24 2006 - 22:35:48 PST
The permanganate can't process the older reversal films very well, or so
I've been told. The pre august 2005.
In a few related questions...
I'm just switching to an Arkay G3 rewind processing tank which holds 32
ounces.
Anyone have any advice about how many times I can use the dichromate bleach
to process 16mm 100' rolls in this tank?
Also, have a similar question about D-19 developer... how many times I can
use it as first and second developer (with decent results) for Fomapan vs Tri
and Plus x reversal? Since the time differs so substantially on those, I
thought I would ask before diving in.
Thanks!
Steven
In a message dated 3/24/2006 5:08:21 P.M. Pacific Standard Time,
email suppressed writes:
R-9 orange (dichromate) bleach retains a long shelf life fully mixed and
can be used multiple times, whereas the purple (permanganate) bleach is
usually recommended for use only one time then discarded.
The purple bleach is made as two separate solutions and mixed in equal
portions just before use.
Purple bleach also requires heavy, continuous agitation, so it is not
recommended for a rewind tank.
A conventional sodium sulfite clearing bath may be used to clear the stain
from either bleach.
If you want to make the purple bleach use this formula:
Solution A:
Water: 500 ml
Potassium Permanganate: 2 g
Solution B
Water: 490 ml
Sulfuric Acid (concentrated): 10 ml
(Add acid to water--never water to acid.)
Unmixed, these solutions will retain a long shelf life. Mix A & B 1:1 for
use and discard afterward.
Ed
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