Quote Originally Posted by greybeard View Post

Nice piece of work. There are a lot of theoretical objections to practical matters voiced in this forum, but in the mantra of the experimentalist, "if it happens, it must be possible".

Would you consider examining non-photographic sodium carbonate and bicarbonate in a similar fashion? I'm pretty sure that the hot-tub and kitchen grades are rather pure; it has been stated (with authority but not necessarily accuracy) that anything but reagent grade contains chloride and is unsuitable for photography. Since I don't make up my own developers that often, I don't have a dog in the fight, but I've always wondered what the facts of the matter were.
In these days of home pools and hot tubs, there should be a reasonably cheap and accurate test for chlorine. The water in Newport News, VA had much chlorine. I used it for photographic work I did for the Norfolk and Peninsula Symphonies and the Old Dominion University Ballet without problem. I didn't realize how bad it was until I had been here in rural WV where the worst thing my well water contains is calcium, and went back to my old house for a night or two. The chlorine in the drinking water was so strong I didn't want to wash my face in it. Chlorides are a different matter and are certainly to be avoided in certain photographic activities, but my experience
at trying to use sodium chloride to reduce grain a la Microdol (they say) was that it took quite a lot to make a difference in practical photography.