[alt-photo] Re: sizing options for color gum

[Diana Bloomfield]

Hey Gord,

I started out with the gelatin and glyoxal, and while I never had an  
issue with the actual coating-- all went on seemingly smoothly--I  
would still get staining in some areas-- despite using "non-staining"  
pigments.  I used both Rives BFK and Fabriano Artistico papers.  I  
then switched to gluteraldehyde and coated outside.  In the beginning,  
I thought there might be a difference (in a good way), but the more I  
used it, the more it seemed to just be more of the same-- except, you  
know, more toxic.  I honestly didn't see the point.  And a couple of  
times things came out sort of yellow (probably from using maybe too  
much glut?).

Then it was Paul -- and maybe Jim Latimer, too?-- not sure-- talked  
about using Gamblin PVA-- and wow-- what a difference.  I also only  
use it on Fabriano soft-press (haven't tried it on Rives BFK), but it  
works like a charm.  I use only one coat (put on AFTER the first coat,  
where I use only the paper's internal sizing), and then I put just a  
thin coat on, which leaves maybe a very slight sheen-- if anything--  
and that one coat seems to last for as long as I need it-- multiple  
layers, for sure.

As I'm sure I've said before, I don't dilute it, and I get absolutely  
no shine or gloss from it, and it does what it's supposed to do.  I  
did, however make a very large print recently, and I found it a little  
more challenging to put a thin PVA layer on such a large print-- so I  
did end up with a shine then.  So for prints that large (20x20 is  
large for me), I do now dilute it 1:1.

I know you're already aware of all this, and this isn't specifically  
what you asked--  but I also recently printed an image on Fabriano  
soft-press without sizing all, using what was only in the paper.  It  
did really well, though I felt the third coat wasn't as "clean" as I  
would have preferred-- so I just went back to using the PVA.  I just  
know for sure, using that, that I won't have a problem.

Anyway . . . I'm not sure why people are so reluctant to use the PVA.   
I often get the sense here that if it's "too easy and works just  
fine," then it can't be right.  Something's wrong.  I cannot imagine  
going back to using anything else, other than PVA, though.  I also  
tried gesso at one point, but I could never dilute it enough to where  
it would work properly.

What is maidstone paper?

Diana

On Jan 15, 2012, at 4:39 PM, Gordon J. Holtslander wrote:

> I'm starting to work with gum printing again.  I want to start doing  
> color gum from digital negatives.  My previous gum work was all from  
> very large format pinhole negatives.  I've been using Maidstone  
> paper.  It worked well with my pinhole negatives.
>
> There are a more sizing and hardening options than when I was doing  
> gum.   I used grocery store knox,  hardened chrome alum.  I used to  
> coat my paper with gum and then soak in chrome alum to harden.
>
> Does higher bloom gelatine make a difference in sizing?
>
> I can't use formalin because I am allergic to formaldehyde, and  
> won't use glyoxal for the same reason.
>
> The new options are Gamblin PVA and gluteraldehyde.  I'm prepared to  
> make a "fume hood" in my darkroom to deal with gluteralehyde fumes -  
> I believe its too cold in Saskatoon, SK to size and dry outside in  
> the winter.  Is gluteraldehyde worth the effort or should I use  
> Gamblin PVA or chrome alum?
>
> What are peoples experience with sizing?   I've done some  
> preliminary work with Gamblin PVA - it looks promising.   I tried  
> undiluted GAmblin - but it was way to glossy. 2:1 Gamblin appearw  
> workable.
>
> Anyone using something different than PVA or hardened Gelatin?
>
> Gord
>
>
> -- 
> Gordon J. Holtslander
> gjh at shaw.ca
>
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