All gummists: Here is a sample of prints made by bleach development. I also made some test strips that illustrate what I might have omitted, or was not evident. Bleach development allows for a long tonal scale of the print with a very smooth tonal gradation from light to o dark. I think this is perfectly illustrated in the test strips http://picasaweb.google.com/marekmatusz1/GumBleachDevelop
On the other hand, I was doing some tricolor yesterday and I have tried my blue (indanthrone ) weakly pigmented layer (weakly pigmented by comparing to "direct carbon method") and I got the same mottled development as Katharine, even worse. Actually it was this that prompted my to coat the pigmented solution made in May this year and repeat the procedure as excatly as the notes would allow. It worked beautifully. I am not even trying to figure this out since I used the same paper, same procedure.
The two pictures in the link were made with same pigment/gum mix. Brownish print has some perylene maroon added to basic carbon black stock.
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