[Alt-photo] Food Grade Chemicals

[eric nelson]

This is a cross post so sorry if you've getting it again.

I've *finally* found ONE chemical supplier here that has some of the
chemicals I need and use, but it turns out that they only supply "food
grade" chemicals.

Now this means that the prices can be cheap, which is good.  While talking
to them, I asked about their prices, which they don't list on their site. (
http://www.ucs1986.com/chemical.htm)  They asked me which chems I wanted,
so quickly scanning the list online I figured Sodium metabisulfite would
give me a good benchmark as to their prices.  1 kilo is 82 THB which equals
$2.63.

Score!

Umm, maybe!

So my question is, how usable are food grade chemicals in photography?  My
guess is that with something like a metal salt (not sure what that would be
doing in "food") in food grade might not be the best choice.  This subject
has been covered at length on this apug posting,  but goes on ad nauseum (
http://www.apug.org/forums/forum37/61248-food-grade-chemistry-ok-use-photography.html)
and I'm hoping for a more concise discussion from personal experiences or
2nd hand experiences even. :)

e

-- 
Eric Nelson Photography
086 343 1612
http://ericnelsonphoto.tumblr.com/
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