Re: DIY light source for 10X10" enlarger.

jjs wrote:
> In return for the good input (and in the original spirit of Usenet) I
will 
> look into the LED array simply to get a realistic idea of what it would
cost 
> for enough light, what the proper power supply would cost, and try to
get 
> the actual color temp of so-called white LEDs and post back. It will
take a 
> while.

http://www.elektor.com/magazines/2008/february/power-to-the-leds.350167.lynkx

You have to pay for the article, but the free description has some links
to
manufacturer's web sites.

> Finally, I must test the electric shutter on B for a few minutes. It was
not 
> used that way in its original camera, but I have a fused box on the
bench 
> and welding gloves. :)

It does not have to be a very sophisticated shutter, a solenoid with
a spring return, or a 1/2 turn stepper motor would do. We are not
looking for exposure accuracy here, the electronics will handle
that (even if it is a pushbutton switch and you control it).

Remember that a 1% variation in exposure is not going to be noticable,
and that could easily be 1/2 second. It depends upon how much straight
printing you want to do versus dodging and burning. :-)


> Tonight I will try to find time to do tentative drawings of a couple 
> housings - one for traditional incandescents, and one for the external 
> lights idea.

Good luck.

Geoff.

-- 
Geoffrey S. Mendelson, Jerusalem, Israel gsm@[EMAIL PROTECTED]
  N3OWJ/4X1GM