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wildbillbugman
06-07-2010, 02:18 PM
...err why do we still have it in Australia?

Because, in Australia all molecules are "mirror images" of what they are in the "real world". L is D and D is Q or Z or something in Sanskrit.:D
Bill

Photo Engineer
06-07-2010, 02:27 PM
Well, the redox reaction between silver and dyes is best undertaken with azo dyes for reasons of stability to the acid pH needed and the post process dye stability. So, most other dyes will not do for this.

Also, most azo dyes contain sulfonic acid moieties that help them dissolve in water and help them stay in the gelatin matrix.

And, I've said that the future of color may be dye bleach due to its inherent simplicity, but don't be fooled. Making the multilayer is going to be a beast. I will be superposing 3 sheets to get a tripack when I do it, I will not be going for the multilayer on one support.

The multilayer invoves:

Overcoat/Blue sensitive Silver Halide/Yellow dye + Blue sensitive Silver Halide/absorber dye and scavenger/Green sensitive Silver Halide/Magenta dye + Green sensitive Silver Halide/scavenger/Red sensitive Silver Halide/Red sensitive Silver Halide + Cyan dye/support. That is about 9 layers.

With good dyes and emulsions, you can omit the interlayers and overcoat sacrificing color purity. You can eliminate the extra Silver Halide only layers sacrificing good contrast control.

PE

Athiril
06-07-2010, 02:59 PM
You make the tinted monochrome version sound easy and simple at least. :P


If I wanted to experiment as quickly as possible, I'm guessing buying a premade liquid emulsion might be the best idea.

Q.G.
06-07-2010, 03:05 PM
Well, the redox reaction between silver and dyes is best undertaken with azo dyes for reasons of stability to the acid pH needed and the post process dye stability. So, most other dyes will not do for this.

Also, most azo dyes contain sulfonic acid moieties that help them dissolve in water and help them stay in the gelatin matrix.

And, I've said that the future of color may be dye bleach due to its inherent simplicity, but don't be fooled. Making the multilayer is going to be a beast. I will be superposing 3 sheets to get a tripack when I do it, I will not be going for the multilayer on one support.

The multilayer invoves:

Overcoat/Blue sensitive Silver Halide/Yellow dye + Blue sensitive Silver Halide/absorber dye and scavenger/Green sensitive Silver Halide/Magenta dye + Green sensitive Silver Halide/scavenger/Red sensitive Silver Halide/Red sensitive Silver Halide + Cyan dye/support. That is about 9 layers.

With good dyes and emulsions, you can omit the interlayers and overcoat sacrificing color purity. You can eliminate the extra Silver Halide only layers sacrificing good contrast control.

PE

I doubt i will ever make a good, or even mediocre, emulsion maker. Have to do a lot of brushing up on chemistry too. And i really mean a lot.
But it's all fascinating stuff, this!

Photo Engineer
06-07-2010, 08:16 PM
You can be a great emulsion maker without knowing chemistry, as long as you follow a tried and true recipe!

Give it a go.

PE

alexhill
06-07-2010, 08:57 PM
I doubt i will ever make a good, or even mediocre, emulsion maker. Have to do a lot of brushing up on chemistry too. And i really mean a lot.
But it's all fascinating stuff, this!

Give it a go! Worst case is you take a workshop. I've been having a lot of fun with it

Q.G.
06-08-2010, 12:36 AM
You can be a great emulsion maker without knowing chemistry, as long as you follow a tried and true recipe!

Give it a go.

I will. I think.
Thanks for the encouragement (you too, Alex)!

What i would really like a lot though, is to understand the thing that makes a "true" recipe a "true" recipe. The Knowledge. To be able to go "well yes, of course" when reading the many things you talk about in film/emulsion making threads.
An unattainable goal. But it should be great fun trying to get there. And for that, i'm sure your book will be invaluable. (So hurry up! ;))
And i'm sure that in the process of soaking up the knowledge, i will give it a go.