Chemistry of darkroom - do you have any links?

[Andrey]

I'm too lazy to get a book on it.

Is there a nice link which describes this stuff? I would like the developer and fixer components broken down one by one, I'd also like to see what reacts with what in formulas.

I've done a chemistry major halfway

 

[richard ide]

Seems to me that you should do the other half of your chemistry major.

 

[Andrey]

Seems to me that you should do the other half of your chemistry major.

Do you mean I should understand what's happening already? I don't get it.

 

[Bruce Osgood]

A very useful site for me is Jack's Photo & Chemistry:

http://www.jackspcs.com/

 

[Photo Engineer]

You want photographic processing chemistry explained to you, right?

Ok, to do that, you have to have some understanding of the subject. That is my take on it.

But, you don't need a full major in Chemistry to do that. Basic first year college chemistry should do the trick. Molecular weights, molarity, molality and redox equations are taught in first year chemistry and that should do the trick.

PE

 

[dancqu]

Is there a nice link which describes this stuff?
I would like the developer and fixer components
broken down one by one, I'd also like to see what
reacts with what in formulas.

There is good coverage of the chemistry specific
to the photographic process at, www.unblinkingeye.com .
Quite a few other technical articles offer insight. Dan

 

[bsdunek]

That's a neat site, Bruce Osgood. I think I'll be spending significant time there educating myself. Thanks!

 

[oldlugs]

Bunch of formula info here: http://www.photocrack.com/photovergne_wiki/index.php/Main_Page#Film_based_photography

You may want to invest in one of these books though: http://cgi.ebay.com/Photo-Lab-Index-1959-18th-Edition_W0QQitemZ370084745116QQihZ024QQcategoryZ629QQssPageNameZWD1VQQrdZ1QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

 

[nworth]

digitaltruth (http://www.digitaltruth.com/data.html) also has a good list.

 

[CBG]

Bunch of formula info here: http://www.photocrack.com/photovergne_wiki/index.php/Main_Page#Film_based_photography ...

photocrack ... some interesting items there, but i have a feeling some of them may have transcription errors. They seem to differ from other sources online.

C

 

[Ian Grant]

You have to be careful of Online sources, the worst of all for errors is Silvergrain.org. Digitaltruth is good, and quickly updated if a mistake is found.

A huge number of errors come from the Photo Lab Indexes which were riddled with typos and errors, unfortunately many US books of formulae used these as there source without cross checking the original manufacturers sources/publications.

The new 3rd Edition of The Darkroom Cookbook, Steve Anchell, contains the correct (manufacturers) published versions of many formulae and is well worth buying.

Ian

 

[Photo Engineer]

I would have to agree with Ian here on the websites cited. I cannot comment on Steve's latest book though as I don't have a copy.

The Handbook of Chemistry and Physics has formulas that have errors in them as do the various Photo Lab indexes.

Part of the problem, which I have argued for a while, is the fact that many in the US use "English" units for the gallon that differ from the Imperial Gallon and etc. Conversion from drams to ounces to grams is often chancy and contain many rounding errors or outright errors in division or multiplication. Perhaps it was due to the lack of calculators back then. IDK. I have found few formulas but my own to be reliable! I use my own stuff for the most part.

PE

 

[oldlugs]

Interesting to hear of the inaccuracies in Photo Lab Index... Are the latest editions any better in that respect?

Duane

 

[Ian Grant]

Interesting to hear of the inaccuracies in Photo Lab Index... Are the latest editions any better in that respect?

Duane

No they were all riddled with the same errors. As Ron says there are errors from Unit conversion, UK Imperial, US & Metric, as well as wrong assumptions on types of various compounds, anhyrous, monohydrated, crystalline etc. All thats before the actually typos and transcription errors.

Ian

 

[oldlugs]

No they were all riddled with the same errors....

Ian

I'm very sorry to hear that, having just bought a copy... I guess for $12 though, it should at least give me an idea for formulas that I wasn't aware of, and can research further from there.

Duane

 

[Ian Grant]

For $12 it's definitely still worth having a copy, there will be formulae not in other publications, and it's also a good starting point. Many Agfa (Ansco) and older Kodak etc publications can be found online.

It's also worth bearing in mind that all the photographic companies offered reasonably similar products/formulae, so personally I chose a variety of devs for printing from just one manufacturer, for a soft working dev, contrast dev, blue-tone, warm tone etc. It's only the more specialist formulae ultra fine grain, etc that differ substantially.

Ian