[Alt-photo] Re: Brushing gelatin on paper

[Loris Medici]

Hi Luciano, the usual size is 3%. I think you've used a too strong solution?


> On 15 Ara 2013, at 19:33, Luciano Teghillo <luciano at lucianoteghillo.com> wrote:
>
> Hi All,
>
> I have been looming in the back an enjoyed the wealth of information all of
> you share. Of course I have not shared nothing because...well, I am just
> getting my feet (actually my paper) wet, as you will see.
>
> I have a question on brushing gelatin on paper. I have prepared the usual
> mix of 30% gelatin and kept it at about 45-50 C and brushed it with a foam
> brush on the print side of my Fabriano Rosaspina paper.
> I brushed on two coats, after letting the first one dry for a day. This
> morning I was getting ready to harden the paper in formalin but I had the
> bad idea of comparing my sheets of paper with a couple of scraps of papers I
> have from two previous workshops.
>
> The papers I was using as a comparison where noticeably more yellow (both
> Fabriano Artistico, Traditional White) when looked on a light table, so my
> doubt is that my paper did not receive enough gelatin. Of course I cannot be
> sure because the samples I used for comparison have been tray sized and not
> brush sized. Also, for least one, the gelatin used is similar to Knox
> (Paneangeli for the Italians), while I used Photographers' Formulary Hard
> Gelatin (250 Bloom).
>
> Also when I compare my sized paper against a sheet of the same unsized
> paper, I cannot see any discernable difference, even under an 8x loupe.
>
> When brushing I load the foam brush, and move horizontally, vertically and
> diagonally with speed (not quite the same as when you coat with pigment, but
> almost), and make sure the brushing is uniform by looking at the surface
> from an angle.
>
> Maybe I brush to fast and "pull" the gelatin too much that it does not get
> into the paper?
>
> Since I have already wasted and entire set of Fabriano Artistico that I
> presume I sized incorrectly, I want to make sure this time I do it
> correctly.
>
> Maybe is something totally unrelated to sizing. Maybe I should harden the
> gelatin before making a comparison.
>
> I  tried to scan the paper samples (mine and those used as a comparison)
> it's useless. You can only see the paper ridges and valleys, but nothing
> else.
>
> I have posted however two images on a previous test I did. The only thing
> different between the two tests is the paper. Everything else is the same,
> done on the same day, developed for the same time, etc.
>
> - http://www.lucianoteghillo.com/images/test01.jpg - This paper was sized by
> someone else.
> - http://www.lucianoteghillo.com/images/test02.jpg - This is the paper I
> sized on a previous batch.
>
> Feeling frustrated....
>
> Thanks for any help,
> Luciano
>
>
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