Hi,
after having found the way to do an almost perfect cyanotype (blueprint is ok - I'm going to experiment with toning now), I also started making VDB prints.
I'm using PDN system to calibrate my R2400 Epson printer and my UV exposure unit. I use Canson transparencies as negatives. Well... after many test prints, I have now a satisfactory color table scale... The problem is the pure black. It is not deep, no matter for how long I set the exposure. To make easier for you to understand, put on your monitor a 0,0,0 RGB square near a 40,40,40 gray block. The brownish black in my finished prints is even lighter...
I normally expose my VDB for 6'. Have tried different papers. I always expose papers when they're bone dry (I dry them with an hairdryer at cool setting)
What it could be? Developing perhaps?
I develop my prints this way
1) 90" bath in water acidified with winegar (ph <7)
2) 30" in 3% sodium iposolphyte fixer
3) 30" in water acidified with acetic acid (stop bath)
4) 90" in 1% sodium sulphyte (hypo-clearing bath)
5) wash for 25'
prolonged or reduced fixing bath won't accomplish better results...
I don't think there's something wrong in the PDN digital calibrated negative... Even with a Stouffer exposure scale or a paper exposed without any negative on it the black will remain the same.
I'm going literally nuts...
after having found the way to do an almost perfect cyanotype (blueprint is ok - I'm going to experiment with toning now), I also started making VDB prints.
I'm using PDN system to calibrate my R2400 Epson printer and my UV exposure unit. I use Canson transparencies as negatives. Well... after many test prints, I have now a satisfactory color table scale... The problem is the pure black. It is not deep, no matter for how long I set the exposure. To make easier for you to understand, put on your monitor a 0,0,0 RGB square near a 40,40,40 gray block. The brownish black in my finished prints is even lighter...
I normally expose my VDB for 6'. Have tried different papers. I always expose papers when they're bone dry (I dry them with an hairdryer at cool setting)
What it could be? Developing perhaps?
I develop my prints this way
1) 90" bath in water acidified with winegar (ph <7)
2) 30" in 3% sodium iposolphyte fixer
3) 30" in water acidified with acetic acid (stop bath)
4) 90" in 1% sodium sulphyte (hypo-clearing bath)
5) wash for 25'
prolonged or reduced fixing bath won't accomplish better results...
I don't think there's something wrong in the PDN digital calibrated negative... Even with a Stouffer exposure scale or a paper exposed without any negative on it the black will remain the same.
I'm going literally nuts...
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