Re: Re: Questions

Quoting "Howard F. Efner" <hfefner@terraworld.net>:

> >1) Given the lack of co-operation from the sun, I feel I need
> >to make an UV light. I think a bank of blacklight fluro lamps
> >is the most practical for me. Is this a good choice ? How
> >few tubes can I start with (I have already blown the hobby
> >budget getting this far). I will allow for more tubes, but
> >how few can I start with ?
>
> Minimum number is one.

Sorry, I did not make myself clear. What I am wondering is how few
tubes I can use and still get even illumination, especially if I limit
the size of print. If I built a BL unit allowing for say 10 tubes,
how few would I need to fit at the start for even illumination of a
smaller print, like a 4x5 or 5x7 ? Then later I could fit the other
tubes.

> >2) I am thinking about making pre-sensitised tissue, and then
> >freezing it. Any suggestions ? How much potassium dichromate
> >do people suggest ?
>
> Sandy will probably have lots to say on this. One thing is with
> pre-sensitized tissue, it is rather difficult to change the contrast of
the
> tissue be changing dichromate levels.

After thinking things out more thoroughly I have concluded that
pre-sensitising will create as many problems as it solves (in my
application). So I think I will stay with unsensitised.

 
> 3) The fixed out photo paper gives a nice surface, but using it
> >really runs against my sensibilities. I thought if I put a thick
> >layer of gelatine on some paper I could achieve a similar effect.
> >So rather than just sizing the paper, I am making what is a thin
> >non-pigmented tissue as a final support. Has anyone tried something
> >like this ?
>
> Not as thick as tissue. I think Sandy recommends one or two coats of a 3
%
> gelatin solution at a rate of 100 mL for a 22x30 sheet.

My idea was to provide a thick enough coating that the carbon image
is not influenced by the paper surface. Two coats at the above rate
may be enough to do this. I have coated some paper as if making tissue.
I will let people know how it turns out.

Richard

---
Richard Urmonas
rurmonas@senet.com.au
-------------------------------------------------
This mail sent through SE Net Webmail
http://webmail.senet.com.au