Vandyke brown question
I've been trying to make some vdb prints during the last couple of weeks. I develop the print in 1% tartaric acid solution. After about 1 minute black spots appear on the edges and start to grow in the fully exposed parts, but occasionally they go into the picture. After fixing the black is washed away forming a light spots.
I can't seem to find what may cause this. Tried it whit whit different papers, developing with tap water or tartaric acid solution, one or two layers of vdb solution and the result is more or less the same.
I'm attaching some pictures. The first one is just before the border becomes black, and the second one is a minute later with a black border.
Hope someone can help.
why are you developing the print in tartaric acid, running water is the usually method, with a "light fix" after that?
I add tartaric acid because I read somewhere that hard water is not good for development. I tried developing in plain running water though and the results are the same.
What paper are you using?
Is it buffered?
Is your sensitizer mixed with distilled water?
What is the pH of your water?
These are among the questions which need to be answered before an educated analysis of your problem can take place.
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I tried with some unknown aquarelle paper, canson montval, arches aquarelle and inkjet paper. I don't really know if it is buffered. I haven't measured the pH of the water, but as it leaves white spots when a drop dries on glass I guess it is alkaline (that's why I add the tartaric acid). The sensitizer is mixed with distilled water and filtered. The brush is used only with this sensitizer.
I will check the wather pH tomorrow.
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How does the print look after fixing? Could you post a picture of a finished print?
I can't take new pictures right now, so that's what I have. The first one is made in the beginning of fixing and the second one is made just before completely dryed. That's the same print as in the firs post. The third one is way overexposed, with wrong negative and not sensitized well, but the result is clearly seen, so I upload it. Usually the result is a lot better than that.
I fix the prints in 5% sodium thiosulfate for 2 minutes, then wash, clear in 2% sodium sulfate for 2 - 3 minutes, then wash again. That's when the black starts to be washed out and becomes neutral gray or white.
Hope someone can give me a clue.
I suspect that something might be wrong with your sensitizer. Were the chemicals fresh? Did the silver nitrate look nice and white? Did any precipitate form when you added the silver nitrate solution to the mix? Could you by any chance have made a mistake when weighing the chemicals?
Did you use the standard formula, namely 9g/1.5g/3.8g per 100ml?
Yes, this is the formula.
The silver nitrate looks fine, the solution was clear, the ferric ammonium citrate works just fine for cyanotypes. Both were opened about a month earlier. Precipitate formed with the last few drops of AgNO3. I filtered it after a couple of days. I am not shure for the tartaric acid because I bought it opened.
I'll try new sensitizer soon, but it may be hard to find AgNO3 again.
Thanks for the help.
I used to do VDB and my results were all over the place. To the point where I gave up and started doing Pt/Pd printing, which is so much easier and predictable. Looking back I was all over the place with my paper choices. There are few papers that work well anymore. Buxton from Ruscombe Mills is designed for iron bases processes. I used to be able to get in in NYC, but it's not available lately. I ordered direct from France. pricey You can get that here:
Then there's COT 320 from Bergger here:http://www.bergger.com/us/special.html
And then there's Weston Diploma. I dealt via e-mail with john Zokowski
E-Mail: email@example.com Good guy and ask for a few samples.
Have you tried palladium printing? I gotta say Bro, Pt/Pd is way easier and trouble free. And when you add up the wasted chemistry paper and fixer and so forth, it's not that much more expensive. But get the right paper. Good luck. Doug Schwab, Brooklyn, NY