Ones that bear distant relations to the ones made now...
Originally Posted by dancqu
It was not that long ago that in any photo store there was a plethora of papers in all tones, finishes, and weights. And a number of brands as well, most of which are long gone, or represented discontinued lines. A recent casualty was Kodak Polymax Fine Art. That paper could be massaged from warm, to cold, to a superb neutral. GAHHHH...
When you come to a fork in the road, take it...
Actually, I rarely found lots of paper in photo stores - even when living in the relatively big city of Atlanta in the 70s. Lots of Kodabromide, a couple of other Kodak finishes, then there was usually only one other brand, either Ilford, Agfa, GAF or Luminos. I think I actually have access to more different papers now than ever.
Originally Posted by dancqu
"BJ Warm Tone Developer for Chloro-Bromide Papers"
Everything is analog - even digital :D
How can I get a 0.2% benzotriazole solution if my benzotriazole is a powder?
You can think of weight in grams and volume in ml to be equivalent. Thus for any volume of liquid, take .2% and use that amount in grams. For instance, if you need 100ml of solution, you add .2 grams of benzotriazole. Since that's probably hard to measure, add 2 grams to one liter.
Originally Posted by smaidimaita
Now one of the real chemists will come along and tell how that's not quite right, but I've found it close enough for photography.
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Okay, I've found some cheap benzotriazole and hydroquinone, but the bottle in which the benzotriazole crystals are kept doesn't seem to be very hermetically sealed. In one old book about the chemistries I found that benzotriazole can be even stored in paper packages. Is that true? Won't years in non-sealed glass botlle affect the blue-toning qualities of the benzotriazole?
Guess it's not the same story for hydroquinone, which seems to oxidate in air very quickly?
I didn't check the cover of the bottle for hydroquinone though.
I live in Latvia, so in situation where the only hydroquinone supplier hasn't got any hydroquinone, it's pretty good to get any kind of hydroquinone at all, even if it's old.
If I COULD get new, I wouldn't bother You with such questions.
Last edited by smaidimaita; 10-26-2006 at 03:08 PM. Click to view previous post history.
Benzotriazole is stable and you should have no problems with it, mine is 40 years old. Hydroquinone will slowly oxidize and should be kept in a glass bottle and away from heat and light. Unless it is very dark brown it should be good. What I have is quite old and has become a grayish color but still works.
Did some test prints, and with Burki and Jenny Cold-Tone developer there was no difference whether I add the benzotriazole or not (and no matter how much) - the Agfa MCP 312 RC still remained neutral tone, not a sign of the blue. That's a bit of dissapointment, though.
Correct me if necessary, but is not the color of B&W paper decided more by grain size or distribution than by dyes? I think the action of BZT has nothing to do with any blue dye that it creates.
Patrick, you are correct. No dye can affect the image tone of B&W papers in an imagewise fashion. Some paper supports are tinted a cream color or a warm browninsh tone for warm tones. Benzotriazole in the emulsion tends to darken tones towards purer blacks.
Grain size and the form of the developed silver both affect the color of the final image.