U of S | Mailing List Archive | alt-photo-process-l | Re: cyano on gessoed Al

Re: cyano on gessoed Al

Hi Loris,

When you do gum on prepared Al sheets, what concentration of AD do
you use, and how long do you need to expose relative to paper exposures?

Looks like I will have to continue building tooth at every step if I
want the colors to blend between successive passes.

Thanks for your input. Rajul

On 10-Apr-09, at 11:52 AM, Loris Medici wrote:

Rajul, thanks for the update. I'm very interested in the agar-agar
-> seems to be useful for other things too (sizing paper - from
Novo - and non-toxic carbon - from Halvor Bjoengaard)...

I currently wait for Henk coming back from his trip -> will continue
trying with "beer coating" after hearing back from him.


9 Nisan 2009, Perşembe, 10:53 pm tarihinde, Rajul yazmış:
To all Al friends,

This is a preliminary observation but I have been able to do cyano on
gessoed Al sheets.

I added finely sieved Aluminum oxide (Al2O3) to the diluted gesso,
and applied multiple coats of it
to achieve the desired opacity. Al2O3 killed the super white of the
gesso, provided tooth, and did not increase the pH. After drying and
lightly sanding coated sheets, I applied 1% agar, and dried them
overnight. I still have to improve on the smoothness of the agar coat
and will try 0.5%. As expected, agar provided the porosity that aids
cyano printing.

A cyano mix of 1A + 2B required a 30 min exposure and printed all
details. However, on development in diluted vinegar, only the shadows
and low mid-tones stayed; all highlights washed out.

I will size these plates and see what gum passes will do.

Details of the process  will follow once I am able to confirm my