More than fixer stink, you should worry about the gas emitted naturally by the developing/printing process. I'm not a chemist and I don't remember the name of the gas, but I will tell you this, a town near here has sirens all over the place to alert residents of an escape of this gas from a nearby refinery. Evacuation time. Same gas - smaller quantity - just as bad for you.
I ran out of rapid fixer today, and discovered my backup jug wasn't Polymax RT Fixer and Replenisher, but instead was Polymax RT *Developer* and Replenisher, so I spent today's darkroom session with plain hypo. In the process, I discovered something interesting (related to smelling the hypo): I alkalized the first batch I mixed with a teaspoon of sodium carbonate in the liter of fixer, and it lasted for a dozen prints and then was tossed out. The second batch, I decided to leave out the alkali -- and after only three prints, it started to get milky and smell like sulfur. Sulfur precipitation is *BAD* in fixer, so I tossed that, mixed a fresh batch with a teaspoon of sodium sulfite in the liter of fixer, and refixed the last print, and it lasted the rest of the session (another seven prints over a couple hours).
What I found interesting is that the fixer lasted for its expected capacity (and more than two hours in the tray) when strongly alkaline, but when initially almost neutral, began to break down very quickly (I presume due to carry over of stop bath and lack of preservative). I think I knew, somewhere in the back of my head, that fixer needs a preservative -- I don't think I'd consciously connected that with fixer breaking down and precipitating sulfur if unpreserved in an acidic solution; I've never previously tried to use plain hypo without alkalizing the solution.
What clued me wasn't so much the milkiness -- I though I'd just made too flat a print (though it was fine on contrast when I pulled it out of the tray) -- but the smell...
If a contact print at arm's length is too small to see, you need a bigger camera. :D
Man, I would use on of the "odorless" fixer formulations. Clayton Chemicals makes one and so does Sprint.
With all the information the science and engineering community has published about chemicals and toxic effects, you have to be a complete nut case to work in a darkroom without ventilation. Really, don't be stupid. Install a fan.
And don't confuse the level of odor with the level of various chemical vapors. Lack of odor does not automatically equate to lack of danger.
Come on people. You know better.
Bruce Watson
Dektol, acetic acid stop bath, and alkaline plain hypo. No aldehydes, no SO2, just a little acetic acid. If salad dressing doesn't hurt me, I'm really not worried about my particular chemicals. And if I can only work in a ventilated darkroom, I have *no* darkroom -- I have a bathroom with a cover over the window, weatherstrip around the door and a towel over the crack at the bottom. Plenty dark to handle high speed film, but given it's a rental house and I can't make permanent alterations (like installing a light trapped vent in the door) an exhaust fan wouldn't make any difference even if I had one -- and the window cover won't stay in place with the window open, even if it had a vent in it.Originally Posted by Bruce Watson
Same old story -- do what you can with what you have, or take up an MMORPG and sit in front of my computer until I have a heart attack during a fierce battle in which I'm moving my mouse hand more than usual...
If a contact print at arm's length is too small to see, you need a bigger camera. :D
Glenn, I'd be very interested in what gas that is. I wasn't aware of development emitting any gas, though acid fixers to give up a tiny bit of sulfur dioxide -- which can be a big problem to people with sensitive lungs, but doesn't bother me enough to notice. Hydrogen sulfide is *very* nasty -- more toxic than hydrogen cyanide, and you lose the ability to smell it at all long before it reaches toxic concentration (your nose simply overloads) -- but common processing doesn't produce any.
If a contact print at arm's length is too small to see, you need a bigger camera. :D
Some of us know how to read a MSDS and work out the real risk involved. My darkroom is unventilated.
The main reason I use plain water instead of a (acetic acid) stop is that I don't like the smell. I've also adjusted my own fixer recipe to be as odorless as possible for reasons of comfort.
The only thing I NEVER use in the darkroom is Viradon. Again it's more due to smell than toxicity!
My 'wet side' is exactly as DQ describes his. Am renting. If my own house, ventilation would go in YESTERDAY.
At the end of a looong day, can taste the sulfur in saliva. either from fumes or hands in fixer occasionally. Mild headache and mild funky feeling either comes from those sulfur coponds in the blood, dehydration, intense focusing, or it's my imagination.
It realy feels like a wine hangover.
Well in 1977 there wasn't a lot of information floating around on the web regarding this
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