Recent content by River Mantis

Do you mean specifically the year 1999 patent mentioned in topic? Because it seems like at some point (according to 1993 patent) Kodak's first developer had slightly more developing agents and lower pH. I also checked Fuji patent and it asks for a double amount of Dimezone-S.

Here are few samples what I got from Velvia 100 using homebrew HQMS-K and CZA. Everything else is as in the patent except the order of preparation of buffer solutions, the absence of any chelating agents and some occasional base substitutions like K<->Na. And there are no accelerators in the...

It indeed works perfectly for both ECN-2 and C-41 (there is a commercial product which uses it) and allegedly for E-6 (because why shouldn't it)

As for potassium sulfate contamination, you can determine the amount by simply precipitating the sulfate with calcium chloride.

BTW do you remember the exact book?

CZA is the easiest here to synthesize. The method from 1893 (!) paper works surprisingly well, except that I kept the temperature at 135º because there is a clue in some later paper that above 150º the CZA (amide) may not form at all. Got about 20% this way

Hey. Nice to see you here. I used the information from these two patents. What I came to is redissolving the sulfonation product (it's almost solid at room temperature) in the 4x excess of sulphuric acid (in the described disilfonate synthesis process it's present from the beginning) at around...

I have all required components to make a chromium intensifier but won't it make the image yellow?

Basically is it even possible?

I have one. The problem is that the warm mode is about two times less bright and I'm starting to have a vibration issue on lower shutter speeds

I'm using a camera

I feel like it's the best approach

I have Braun Paximat De-Luxe slide projector from 1950s and the only magazine type you can buy new in 2025 is Agfa CS. Are they even compatible? I use CS frames anyway.

I have an established workflow for black and white negatives but I have never worked with color slides before. So here are my thoughts. Ektachrome E100 is a daylight balanced film. When applied to a transparency it means, I guess, that the white card shot under daylight will have the color of...

In Bulgaria you still can buy sulphuric acid freely. You can buy dichromate as well if you have a legal entity but I indeed managed to buy it with no questions asked.