[Alt-photo] gum 'solarisation' issue

Edward Draper platinumprinz at gmail.com
Tue Aug 1 05:32:45 UTC 2017

Last Year I did a lot of work on pigment levels with gum to try to find the maximum pigment loading with gum

When you overload the pigment, especially lamp black, you get an interesting solarised effect. With regions of the image completely reversed. This is most noticeably when you only just overload the pigment. I use a quantity of pigment that only just avoids solarisation - I believe it to be the maximum I can get away with

The effect I think is something to do with the light only penetrating the very topmost layer leaving the lowermost layer next to the paper essentially unexposed and so it washes away

I've not got the necessary microscope equipment to study this phenomenon in more depth. And did consider trying a "gum transfer", which in theory, if I'm right, would allow me even greater levels of pigment.

Hope this helps,


Working on the go on a screen keyboard - forgive minor errors, please

The big errors you should challenge

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