Ryuji said:In my opinion, it is not very useful to worry too much about supply of raw chemical stocks.
Donald Qualls said:Ryuji, one of the big issues is getting anything that ships as a powder past Philippine customs, apparently. They tend to assume it's disguised drugs, and (I'd guess) "test" it until there's nothing left to deliver to the addressee. Otherwise, he'd just order metol, phenidone, dimezone S, etc. from an American or UK supplier, as you've suggested. And the point of the whole thread is that there are *no* B&W developers available in his area (around Manila, wasn't it?).
Ryuji said:It's hard to believe. Don't they make better "drugs" than most parts of the world? Why do they want to buy stuff from the US or UK? (Ok, maybe amphetamines come from N Korea but that's a different story.)
And, if they don't sell developers, why do they make b&w films available?
There are a lot of comopunds that can be used as a b&w developer, from iron oxalate to color developers, but in terms of image quality it would be best to get some phenidone type agents.
ZorkiKat said:It will be easier for a camera to pass through the eye of
a needle than strange looking powders through customs.
dancqu said:I wonder at such close scrutiny? Is it a way to keep
people employed? Fine tooth combing all that comes
into the country? Dan
gainer said:Just remember that p-aminophenol and ascorbic acid are superadditive for developing film and can be used with several different alkalis to make interesting and usefull developers.
I met an interesting fellow in Santa Ana province in 1946, a Russian gone native, probably connected with the Hukbalahap, who made his own acetylene generator and did much mechanical work for the village. The Philipinos were, and probably still are, very adept at making something useful out of junked Army vehicles. Just a matter of interest.
I was there directly after the war. I was with the Corps of Engineers as a topographic computer. We were to assist the Coast and Geodetic Survey in first order mapping of the Philipines. I think accurate aerial mapping actually did the job later. I was only in the service for 18 months, 9 of them near Manila. I admired the people more than I can tell here, and was actually sad to have to leave.ZorkiKat said:Thanks Gainer. Interesting story. So you were here in WW2? I've heard of stories about 'lost' Russians here, usually 'white' refugees who escaped the 1917 revolution. The reworked army jeeps evolved into the 'jeepney' which is seen everywhere now. They have grown larger and longer than what was seen in the late 1940s. They are now mainly used for public transport.
Going back to developers- can a combination of paRodinal+sodium ascorbate be able to produce an equivalent to an MQ high contrast/high density developer? Ascorbic acid, as well as the other reagents like sulfite, bromide, carbonate, bicarbonate, borax, etc, needed to brew developers are still available. Its only the developing agents which are hard to get, having limited applications and vitually zero demand at present.
Ryuji, are you speaking from experience or from theory? I once did a Q&D side-by-side test of hydroquinone and ascorbic acid as lith developers. I seem to remember very similar gradations with an edge in film speed to the hydroquinone. I'll try again. Maybe it was too quick or too dirty.Ryuji said:Ascorbate won't work as a lith developer. Ascorbate-alone developer will take forever to develop AgX in gelatin, and even then, the contrast won't be anywhere near the classic hydroquinone lith developer.
Quick comment on Donald Qualls's post. Ammonium hydroxide is a bad choice in developer, unless you want unstable developer with high risk of dichroic fog and/or large grain. Also, food grade ascorbic acid is cheaper than acetaminophen, and technical grade erythorbic acid is also cheaper.
gainer said:Ryuji, are you speaking from experience or from theory? I once did a Q&D side-by-side test of hydroquinone and ascorbic acid as lith developers. I seem to remember very similar gradations with an edge in film speed to the hydroquinone. I'll try again. Maybe it was too quick or too dirty.
Ryuji said:Quick comment on Donald Qualls's post. Ammonium hydroxide is a bad choice in developer, unless you want unstable developer with high risk of dichroic fog and/or large grain. Also, food grade ascorbic acid is cheaper than acetaminophen, and technical grade erythorbic acid is also cheaper.
Donald Qualls said:However, I *have* used ammonium hydroxide in a developer with repeatably good results -- I used it to control pH in my HC-110 based, rapid fixer monobath. Since HC-110 already uses an ammonium-based alkali, I figured I wouldn't introduce anything horrible by using it to offset the acidity of the rapid fixer concentrate, and the results I got were well within the range normally expected from a monobath.
gainer said:My experiment as I remembered it was a teaspoon each of hydroquinone, potassium bromide and sodium hydroxide in a pint of water in one case, substituting a teaspoon of ascorbic acid for the hydroquinone in the other. It is true that the hydroquinone mix showed the exponential buildup of density expected of infectious development: nothing much happened to a two-minute snip test in the first minute, and very dense black in the second. Nowhere near this density was reached in the ascorbate mix.
Triethanolamine is a sort of analog of ammonia with ethanol in place of each hydrogen in NH3. I suppose it would be better to use it to control HC110 than ammonia.
gainer said:Certainly hydroquinone alone has a long induction period during which nothing appears to be happening. However, the development rate is accelerating. A simple snip test as I did would show that, and that is probably what I saw. We would have a difficult time proving infectious development. A grid of exposed and unexposed lines would show widening of the exposed lines with infectious development, but where do we find an emulsion that has absolutely no fog density in "unexposed" areas?
What causes the acceleration of the development rate? There was no sulfite, only hydroquinone, NaOH, and NaBr.
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