RE: haunted GUM (i surrender)
BTW, those exposure times are for the usual UVBL lightsource and can be too much for sun exposures. For sun exposures start with 5 seconds and go up from there - making enough test strips. Brush well the sizing; you need it to fill the deep pores only, w/o completely blocking the surface! -----Original Message----- From: Loris Medici [mailto:mail@loris.medici.name] Sent: Friday, October 09, 2009 9:09 AM To: 'alt-photo-process-l@usask.ca' Subject: RE: haunted GUM (i surrender) Phritz, are you sure your previous batch of paper had inteed hardened sizing? Is it possible you've problems in hardening the sizing? Such as: not waiting enough before starting to print or not enough - or too much??? - hardener in the sizing? Hardener going bad - does chrome alum keep in solution? (If you're using a stock solution that is...) Can't comment about tonal inversion but now looking at them again your examples looks like printing on paper with unhardened sizing. (Not everyone has problems with this apparently but I remember clearly it gave severe staining to some of our master printers...) Try to size few sheets of paper with dichromated gelatin. Never tried that before but I'd start with 3g jelatin + 3g dichromate into 100ml (add the dichromate after melting gelatin), coat, dry the sizing with a fan and expose w/o a negative for 15, 30, 45, 60, 90 and 120 seconds, wash, dry, evaluate and use the exposure time which gives you enough hardening and no or little dichromate stain... Maybe your chrome alum is the real problem not anything else? (BTW, you can try clear gum+dichromate as a size too.) Regards, Loris. -----Original Message----- From: phritz phantom [mailto:phritz-phantom@web.de] Sent: Friday, October 09, 2009 3:44 AM To: alt-photo-process-l@usask.ca Subject: Re: haunted GUM (i surrender) ... i will now size some paper, which will take one or two days to harden. i will then make some more tries with sized paper. gum is the devil
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