Re: Lightsource for Gum

To: alt-photo-process-l@usask.ca
Subject: Re: Lightsource for Gum
From: Henry Rattle <henry.rattle@ntlworld.com>
Date: Mon, 11 Aug 2008 23:03:30 +0100
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Title: Re: Lightsource for Gum

Hi Bjorn,

I guess everyone does this differently – I take a minimalist approach, because I don’t work bigger than about 28x20 cm (A4 size negatives) which makes everything much simpler.

I use five 20-watt blacklight tubes. They are marked Sylvania Blacklight F20W/350 BL, and are about 60 cm long and 3.5 cm in diameter. Each is fitted to a separate single-tube holder, and these are mounted close together on a piece of board about 68x38 cm. Negatives are exposed at a distance of about 15 cm from the tubes, and I have never noticed any unevenness in exposure. Exposure times are around 5 minutes for gum and 10 minutes for cyanotype.

Anyone else?

Best wishes

Henry

On 11/8/08 17:39, "Bjørn Frostad" <myrvandrer@hotmail.com> wrote:

Hi everyone!
Thanks for all of your answers on this topic, and sorry for bringing it up once again....
...But just so I get it right from the begining:

-    Wich tubes avalible on the market today will give the the best results? - And is there any tubes that won't?
-    How many tubes will I need?
-    How far away from the print should the tubes be?

Thanks again

Bjørn

References:
- Lightsource for Gum
  - From: Bjørn Frostad <myrvandrer@hotmail.com>