View Full Version : Grain-like pattern left on print

12-01-2006, 01:50 AM
Hello all!
Recently I had the chance to join some friends in making a few salt prints.
I found the process and ultimately the results to be rewarding, but I have a problem.
Of the three prints I made, and the several others my friends made, two show a distinct wood-grain like pattern. The materials and processes involved were the same for all of us, down to where we coated our paper.
Now the only explanation I can figure is that the paper was still wet after the salt coating or the silver coating. For expediency we used a blow-dryer to speed up the time after the salt coating, so it is possible that the paper was still wet before coating it with silver. There was no apparent moisture on the reverse of the transparency and it didn't stick to the paper upon removal.
Any thoughts?

12-01-2006, 04:02 PM
I can't help specifically, but it sounds like you have a good evaluation approach.

Unless it's too big a nuisance, you could try another batch and change only the drying time...intentionally introduce significant variation on one or two (or two sets >1). Do one or some as you think you did previously, and do a couple with paper allowed a much longer drying time.

Or a variation of this scenario; give two prints less drying time, do two as you did previously, while you let two more dry longer (overnight?).

The prematurely dry ones compared to the same-as-before ones and those compared to the longer dry time ones may confirm if it was a humidity or moisture problem. Many of those processes give tone/color variation with humidity.

Do the negatives look OK afterward? With some alt-processes people worry about contact with the chemicals and use very thin plastic like food wrap to protect the negs.

Not sticking to the paper sounds like a paper characteristic...mixed batches in same box (assuming it was all same paper), sizing variation (manufacturing variaton among paper sheets, again suggestive of different batches.)

I thought this type of sensitizer was supposed to absorb into the paper, rather than sit on it like an emulsion or coating. If it is not absorbing there may be something in the papers chemistry preventing absorption.

There is a product called 'Tween' some people add to iron/silver and Pt/Pd sensitizers. I think it helps absorption.

There is a very active list(sev group) called alt-process based in Saskatchewan, Canada(University of?). It's run by Gordon Holtslander...you want to sign up & ask some questions there too.