Path: utzoo!attcan!uunet!aplcen!samsung!cs.utexas.edu!rutgers!mcnc!rti!bbt!djb
From: djb@bbt.UUCP (beauvais)
Newsgroups: comp.misc
Subject: Re: photo of crt
Keywords: photo, crt
Message-ID: <540@bbt.UUCP>
Date: 1 Mar 90 14:16:28 GMT
References: <146@tslwat.UUCP>
Reply-To: djb@bbt.UUCP (beauvais)
Organization: Broadband Technologies, Inc., Research Triangle Park, NC
Lines: 38

In article <146@tslwat.UUCP> louk@tslwat.UUCP (Lou Kates) writes:
>Does anyone have any experience in taking photos of what is on a CRT screen?
>What lighting, if any, should be used, what f stop, what shutter speed?  I
>am using a 35 mm camera.
>

I have several suggestions:

Use a longer focal length lens - 100 mm or above.  Telephoto lenses
compress depth, minimizing the effect of the curved CRT screen.

Stop down the lens for greater depth of field.  This is necessary because
of the curved CRT screen.

Use a tripod.  That way, you only have to align and focus once, and you can
do it all with the lights on!  (More on that later)

Make sure your lens axis is at a right angle to the screen.

Lighting is simple - NONE!!!!  Shut off ALL lights or completely shade the
screen or you will get reflections, or at a minimum, a washed out screen.
Don't use a flash!  The image on the screen provides all the light the
exposuer needs!

Your shutter speed should be 1/30 of a second or slower (1/15, 1/8.....).
Otherwise, part of the screen will be much brighter than the rest because
the shutter wasn't opened long enought for a full retrace of the CRT image.

I determined my exposures by writing a program which flooded the screen
with a gray color - assumed to be halfway between all black and all white.
I made a meter reading from it.  If this is not possible, I would try
flooding the screen with characters, meter off this screen as a starting
point, then bracket your exposures a couple of stops in either direction.

Use a slower, finer grained film.  Kodachrome 25 or 64, or Fujichrome 50
for slides, T-Max 100 or Tech Pan for B&W, Kodacolor 100 for prints.

E-mail if I can help any further.  Good luck!