Bleaching salt print
These are the images I'm having trouble with.
untouched scan b
untouched scan a
Bleaching salt print
Definitive instant - for real
Final Barn photo
Palouse, SE Washington State

Bleaching salt print

I've been making salts for a little while now and thought I might test a print to see whether my workflow is OK.
I covered part of the print with a piece of opaque plastic and set it on a south facing windowsill for full sun (slight joke for us UK residents, but its the best I can do) The result after about 2 months is that the upper, exposed part has bleached from the sun's exposure. If there was to be any change to the print I expected it to be possibly mottled, colour change, darken but not to get lighter.
Has anyone any suggestion as to the reason.
Workflow basically, wash, fix, wash. No tone to this print. Thanks for any help.
Click to expand...
Paper & Developer
Fabriano Artistico
tony lockerbie
Just simply it is the UV exposure, pretty deadly stuff on any image, even a fairly archival one. Here in OZ, the UV is really aggressive, I use a UV coated glass for any images that I frame that will be in a bright area.
What is amazing here is that you can find enough UV in the Old country to fade anything! :smile:
 
artonpaper
Just to add that tony lockerbie has hit the mark. That seems the most reasonable explanation. Chemically, though, I'm not sure what is going on. The fact that it's gotten lighter could mean the silver has gone back to a halide state, but I'm not sure why UV would do that. Perhaps there is another compound being formed that makes for a lighter image. Maybe one of the photo chemists will chime in.

I wonder how a gold toned print would have reacted. BTW, you have gotten a very nice image tone for an un-toned print.
 
artonpaper said:
Just to add that tony lockerbie has hit the mark. That seems the most reasonable explanation. Chemically, though, I'm not sure what is going on. The fact that it's gotten lighter could mean the silver has gone back to a halide state, but I'm not sure why UV would do that. Perhaps there is another compound being formed that makes for a lighter image. Maybe one of the photo chemists will chime in.

I wonder how a gold toned print would have reacted. BTW, you have gotten a very nice image tone for an un-toned print.
Click to expand...

Thanks for both above inputs : I'll accept that it is caused by UV and like any image keep them from direct sunlight.
As for gold toned version; I am present doing the same test to see if I get the same result. Will be interesting, we've had nothing but cloud and rain on/off for the past 2 weeks or so, so this could be a long haul.

If there are any chemists viewing this perhaps you might make an opinion
 

Media information

Category
Technical Gallery
Added by
ColinRH
Date added
View count
570
Comment count
3
Rating
0.00 star(s) 0 ratings

Image metadata

Filename
test_salt.jpg
File size
88.9 KB
Date taken
Mon, 20 June 2011 5:06 PM
Dimensions
800px x 611px

Share this media

Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:
Ilford ADOX Freestyle Photographic Stearman Press Weldon Color Lab Blue Moon Camera & Machine
Top Bottom