[pure-silver] Re: Converting a camera into an enlarger?
From: "Richard Knoppow" <dickburk@xxxxxxxxxxxxx>
To: <pure-silver@xxxxxxxxxxxxx>
Date: Wed, 6 Apr 2005 13:52:29 -0700
----- Original Message -----
From: "Koch, Gerald" <gkoch02@xxxxxxxxxx>
To: <pure-silver@xxxxxxxxxxxxx>
Sent: Wednesday, April 06, 2005 6:46 AM
Subject: [pure-silver] Re: Converting a camera into an
enlarger?
>I haven't been closely following this discussion so someone
>may have
> already mentioned this. Fluorescents take a anywhere from
> a few seconds
> to a few minutes to reach maximum light output. They are
> therefore a
> poor choice for use in an enlarger since exposure times
> would be
> inconsistent.
>
> Jerry
>
That's true but they have the advantage of running fairly
cool for the amount of light emmited. As I stated the lamps
really should be run continuously and exposure controlled
with a shutter. All gaseous discharge lamps have the same
property, the light increases as the lamps get warm. Aristo
uses an auxilliary heater to keep the lamps warm between
exposures but I think lamp life and performance is better
when the lamps are allowed to run cntinuously. The ancient
Saltzman enlargers used Cooper-Hewett type mercury vapour
lamps and had a Packard type shutter operated by a foot
pedal to control exposure. Large incandescent lamps are too
hot unless one builds a fairly complicated lamphouse with
some sort of heat absorbing device in it.
---
Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx
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