JD3 bleach

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highwaychile

JD3 bleach

Post by highwaychile »

Hi,

I want to use the JD3 bleach normally consisting of Copper Sulfate, Potassium Bromide and Succinic Acid. I've the problem that I've all the things I need except Succinic Acid which I've forgotten and has to be ordered. As I've some other types of acids here I'd like to ask whether it's possible to use another acid instead?

Thanks in anticipation,
highwaychile
Ed Wesly

JD3 bleach

Post by Ed Wesly »

Here is what I know abut this bleach:

JEFF BLYTH'S COPPER SULFATE

35 g Copper Sulfate
10 ml Acetic Acid
110 g Potassium Bromide
One litre water

Bleaching time: One and a half times the time it takes to clear.

Temperature: 20C Agitation: Intermittent

Shelf life: Unused solution seems to last for weeks, but it does get tired with use.

The best "Cure for PBQ". Identical results to the above, less costly than Fe EDTA, pleasant blue-green color when mixed, dirty green when exhausted. This is the bleach that is supplied in the Photographers’ Formulary JD-3 and JD-4 kits, except dry succinic acid is used instead of liquid acetic acid.

Source: Jeff Blyth, "A Novel Approach to Colour Processing", Wavefront Volume 2 Number 3, p.23 (1987)

Might be able to find acetic acid in a well-equipped photography store, (at least used to!), or maybe even use vinegar, but you'd have to find out how much acetic acid is in the vinegar.
Danny Bee

JD3 bleach

Post by Danny Bee »

Ed Wesly wrote:Here is what I know abut this bleach:

JEFF BLYTH'S COPPER SULFATE

35 g Copper Sulfate
10 ml Acetic Acid
110 g Potassium Bromide
One litre water

Bleaching time: One and a half times the time it takes to clear.

Temperature: 20C Agitation: Intermittent

Shelf life: Unused solution seems to last for weeks, but it does get tired with use.

The best "Cure for PBQ". Identical results to the above, less costly than Fe EDTA, pleasant blue-green color when mixed, dirty green when exhausted. This is the bleach that is supplied in the Photographers’ Formulary JD-3 and JD-4 kits, except dry succinic acid is used instead of liquid acetic acid.

Source: Jeff Blyth, "A Novel Approach to Colour Processing", Wavefront Volume 2 Number 3, p.23 (1987)

Might be able to find acetic acid in a well-equipped photography store, (at least used to!), or maybe even use vinegar, but you'd have to find out how much acetic acid is in the vinegar.
Ed how does this compare to PBU ? is it better? what about noise?
Ed Wesly

JD3 bleach

Post by Ed Wesly »

Not having used PBU in recent memory, it's probably the same. CWPBQ2, Fe EDTA's, this one, all pretty much look the same, and since the PBU family of bleaches is of the same type, rehalogenating without fixing, it's probably similar in brightness, but maybe only a difference in shrinkage. Mix up a batch and compare, I am not in a position to do that kind of experimenting at the moment!
Martin

JD3 bleach

Post by Martin »

Ed Wesly wrote:Not having used PBU in recent memory, it's probably the same. CWPBQ2, Fe EDTA's, this one, all pretty much look the same, and since the PBU family of bleaches is of the same type, rehalogenating without fixing, it's probably similar in brightness, but maybe only a difference in shrinkage.
Quite right. Typically, this bleach does shift reconstruction wavelength towards red.
Tom B.

JD3 bleach

Post by Tom B. »

Acetic acid in white table vinegar is typically 4-5%. My 2L jug of Safeway Pure White Vinegar says 5% by volume. It is completely artificial, produced from acetylene extracted from natural gas. Great for fish and chips and stop baths.
Colin Kaminski

JD3 bleach

Post by Colin Kaminski »

Tom B. wrote:Acetic acid in white table vinegar is typically 4-5%. My 2L jug of Safeway Pure White Vinegar says 5% by volume. It is completely artificial, produced from acetylene extracted from natural gas. Great for fish and chips and stop baths.
Yuck! I really need to start making my own vineger for my fish and chips. Thank you for the heads up.
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