Re: Tiny Bubbles In The ... Gum

The hair brush is boar's hair, the cheapest of the cheap, disposable. I buy
them at Lee Valley for $10 for 30 brushes. But hair is hair or so I thought,
then again you get what you pay for, right. I'm going to hunt down a water
color brush and try again tonight. No shrinking and no gelatin was used.
Rives BFK I had same issue on some Stonehenge too come to think of it. The
gum is whatever Photoformulary ships with their kits. I imagine it's decent
quality. I'll post back in a couple of days when I've tried some of the
suggestions posted here. Thx.

~m

Katharine Thayer wrote:
> Michael Koch-Schulte wrote:
>>
>> I don't think it's contaminated paper if that's what you're getting
>> at.
>
> No, that's not what I had in mind at all; I think that's most
> unlikely.
>
>
> I
>> thought maybe foam brushes might cause this because of the rough
>> bubbly edge surface.
>
> I would agree that foam brushes could put air bubbles into the
> emulsion, but I understood you to say that you had the same problem
> with a hair brush.
>
>> I'm wondering if the paper is releasing air because its dry.
>
> Extremely unlikely, in my opinion.
>
> My
>> paper has not been pre-shrunk or sized in any way.
>
> Since you're using the paper unsized, it's also quite unlikely that
> the problem is beading caused by too thick a coat of gelatin, as I
> suggested before.
>
> I switched to a hair
>> brush but it didn't seem to make much difference.
>
> Is this a soft hair brush or a boar bristle brush -- it could make a
> big difference. Softer is better in my experience.
>
> I don't want to "work" the
>> paper too hard because I'm afraid of roughing it up.
>
> What paper are you using?
>
> I've read that most
>> people lay down a quick coat and then smooth it out.
>
> Yes, that's what I do, like Dave described.
>
>
> I'm having problems
>> with the smoothing out part it just seems to make things worse. If
>> my mix has low visocity could that cause it? ie too runny?
>
>
> Yes, in fact my first thought was that perhaps you had added too much
> water, until I saw that you hadn't added any water at all. But I'm
> not sure how you could get low viscosity if you're using 14 baume gum
> with no added water. (Yes, I remember Gordon; viscosity and specific
> gravity are not correlated, but still I have a hard time seeing how
> this could be.) What are you using for gum?
>
> Sorry to be answering with more questions instead of easy answers, but
> this is how it often works with gum.
> Katharine
Received on Sun Aug 28 21:05:09 2005