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- Sep 2, 2006
- Messages
- 212
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- 35mm
I've started platinum/palladium printing (well palladium na2) and I'm happy with progress but I'd like to resolve some interesting observations (and slightly annoying ones but it's all the journey).
I've attached two images. The second is a 'normal' scan of the print and the first is a bigger version with the contrast boosted.
The chemistry is 2 drops of 2.5% na2 and 20 drops of oxalate and 18 drops of palladium.
Coating done at room temperature with a Richeson brush
One piece of paper was brushed back and forth about 8-10 times to get a full coating (coating area just under 8x10).
The second piece of paper I graduated from the top to the bottom of the paper with 2 passes, 3,4,5,6,7 & 8 passes and then a bit of pooling at the bottom in the 8 area.
The paper was COT320 wasn't pre-humidified. The humidity was probably 40%.
I dried the paper in the room which was probably about 18 degrees C. No force drying so it probably took about half an hour to touch dry and then the paper was stored in a box.
I used my usual exposure time for pictorico digital negs but used my black and white 4x5s for one peice of paper and just masked off half of the other piece of paper.
The idea was both to test my coating with the Richeson 4" to work out how much is too much brushing but also to test contact printing my old 4x5 negs.
What surprised me was two things
1) I didn't need many passes to get a decent coat but there was a little incremental increase in dmax where there was some pooling.
2) The central area of the coating lost dmax but the edges (and not just the extra wet edges) kept dmax.
3) The areas that got more than max dose of UV went brown
4) areas that were masked by the film base were colder and denser
1) This is good
2) I'm thinking that the central area stayed wetter longer and the coating went too deep into the paper?
3) This is bronzing as far as I understand it (with a bit of solarisation).
4) I'm presuming that the areas that got the 'perfect' exposure didn't bronze and weren't solarised.
My main question is about the way that the coating is bronzed in the centre but better towards the edges.. If anybody can comment on my results I'd be very interested.
I suppose my question is how many times do you brush coating on your paper? Do you force dry? Have you seen results like this? Is the colour change bronzing? blah blah - you get the idea.
Many thanks in advance!
UPDATE: I found a thread including David Fokos saying double coating would help (http://altphotolist.org/lists/alt-photo-process/1996/alt96a/0785.html) and also a Mike Ware extract in the same thread suggesting humidifying prior to coating.
UPDATE 2: Here's another thread I was reading that suggests humidification. Thought I'd collect the references together here. (http://www.dpug.org/forums/showthread.php?t=2516)
I've attached two images. The second is a 'normal' scan of the print and the first is a bigger version with the contrast boosted.
The chemistry is 2 drops of 2.5% na2 and 20 drops of oxalate and 18 drops of palladium.
Coating done at room temperature with a Richeson brush
One piece of paper was brushed back and forth about 8-10 times to get a full coating (coating area just under 8x10).
The second piece of paper I graduated from the top to the bottom of the paper with 2 passes, 3,4,5,6,7 & 8 passes and then a bit of pooling at the bottom in the 8 area.
The paper was COT320 wasn't pre-humidified. The humidity was probably 40%.
I dried the paper in the room which was probably about 18 degrees C. No force drying so it probably took about half an hour to touch dry and then the paper was stored in a box.
I used my usual exposure time for pictorico digital negs but used my black and white 4x5s for one peice of paper and just masked off half of the other piece of paper.
The idea was both to test my coating with the Richeson 4" to work out how much is too much brushing but also to test contact printing my old 4x5 negs.
What surprised me was two things
1) I didn't need many passes to get a decent coat but there was a little incremental increase in dmax where there was some pooling.
2) The central area of the coating lost dmax but the edges (and not just the extra wet edges) kept dmax.
3) The areas that got more than max dose of UV went brown
4) areas that were masked by the film base were colder and denser
1) This is good
2) I'm thinking that the central area stayed wetter longer and the coating went too deep into the paper?
3) This is bronzing as far as I understand it (with a bit of solarisation).
4) I'm presuming that the areas that got the 'perfect' exposure didn't bronze and weren't solarised.
My main question is about the way that the coating is bronzed in the centre but better towards the edges.. If anybody can comment on my results I'd be very interested.
I suppose my question is how many times do you brush coating on your paper? Do you force dry? Have you seen results like this? Is the colour change bronzing? blah blah - you get the idea.
Many thanks in advance!
UPDATE: I found a thread including David Fokos saying double coating would help (http://altphotolist.org/lists/alt-photo-process/1996/alt96a/0785.html) and also a Mike Ware extract in the same thread suggesting humidifying prior to coating.
UPDATE 2: Here's another thread I was reading that suggests humidification. Thought I'd collect the references together here. (http://www.dpug.org/forums/showthread.php?t=2516)
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