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Two23
7-Jul-2020, 15:59
Looks like it's going to stay hot here for the foreseeable future. On my outings over the weekend I noticed the blue image came up pretty fast with correct exposure. I decided to modify my developer to match the temps. The standard formula is aimed at ~68 degrees, just like b&w developer. Looking up in my Coffer's manual I found the suggested formula adjustment was to add about 30ml distilled water and an extra 6ml of glacial acetic acid per 100ml. So, I mixed my B&S stock developer 1:4 instead of 1:3 (50ml developer / 200ml water) and added an additional 10ml glacial acetic acid. I'll find out how that does later this week.


Kent in SD

paulbarden
8-Jul-2020, 07:04
Looks like it's going to stay hot here for the foreseeable future. On my outings over the weekend I noticed the blue image came up pretty fast with correct exposure. I decided to modify my developer to match the temps. The standard formula is aimed at ~68 degrees, just like b&w developer. Looking up in my Coffer's manual I found the suggested formula adjustment was to add about 30ml distilled water and an extra 6ml of glacial acetic acid per 100ml. So, I mixed my B&S stock developer 1:4 instead of 1:3 (50ml developer / 200ml water) and added an additional 10ml glacial acetic acid. I'll find out how that does later this week.


Kent in SD

Kent,
I have no idea how well the B&S developer will work when fiddling with the recipe, although your assumptions about diluting + adding acid are the right idea, in principle. The B&S developer contains a second restrainer: sucrose, so I have no idea how the addition of more acid will affect its behavior. Let us know how it goes.
For warm weather work, I prefer to make developer from scratch, using a tried and true recipe designed for such work.

Two23
8-Jul-2020, 07:15
Kent,
I have no idea how well the B&S developer will work when fiddling with the recipe, although your assumptions about diluting + adding acid are the right idea, in principle. The B&S developer contains a second restrainer: sucrose, so I have no idea how the addition of more acid will affect its behavior. Let us know how it goes.
For warm weather work, I prefer to make developer from scratch, using a tried and true recipe designed for such work.


What is this warm weather recipe? I do have glacial acid, Fe sulfate, sugar already.


Kent in SD

paulbarden
8-Jul-2020, 07:56
What is this warm weather recipe? I do have glacial acid, Fe sulfate, sugar already.


Kent in SD

If you have Coffer's manual, its in there: page 40 has the base formula, and page 42 has the warm weather modification notes. Publishing the recipes here may be a violation of JC's copyright.

Two23
8-Jul-2020, 08:08
If you have Coffer's manual, its in there: page 40 has the base formula, and page 42 has the warm weather modification notes. Publishing the recipes here may be a violation of JC's copyright.

That's the recipe I was basing on.


Kent in SD

paulbarden
8-Jul-2020, 08:30
That's the recipe I was basing on.


Kent in SD

I'm confused now - your opening post said you were modifying the Bostick & Sullivan recipe.