Re: filmscanners: Correction for daylight slides with artificial light

["Maris V. Lidaka, Sr." <mlidaka@ameritech.net>]

If using Photoshop you could click with the White eyedropper, the Gray (pick 
your own gray numbers for each image) and the Black and you should have basic 
adjustments.  But this will not work 100% of the time because sometimes Curves 
will be necessary - and very intricate Curves - so the filter set may well be 
more useful.  Different objects in the image may have differing reactions to 
the fluorescent lighting - some may be fairly OK and others way off.

Maris

----- Original Message ----- 
From: "Arthur Entlich" <artistic@ampsc.com>
To: <filmscanners@halftone.co.uk>
Sent: Tuesday, December 04, 2001 4:37 PM
Subject: Re: filmscanners: Correction for daylight slides with artificial light


Thanks for the info on your approach to correcting fluorescent lighting.

If you were not interested in having a "filter set" wouldn't just
clicking with the clear eyedropper in levels at the same (near white) 
location do a basic adjustment?

Art

Mário Teixeira wrote:

 > Thanks Art and all the others that helped. In fact, trying to correct 
with
 > levels in PS was beeing truely difficult -- I don't remember very 
well the
 > true color, reproductions in books that I have doesn't seem very 
"true" and
 > I was not liking the results. Happily, I ended remembering  that I read
 > something about correction with inverse colors. After many trials I 
got an
 > approach that seems to work. I post it in the hope that it can help 
others:
 > 1- Pick the color of a white structure (I choose a ceiling near a
 > fluorescent light); 2 - Aplly an overlay layer with the inverse of this
 > color.
 >
 > This makes a filter that I can apply to the other slides (as a starting
 > point) much better than all my other tries. While it cannot correct 
for the
 > uneven illumination, results are very agreable and also very plausible.
 >
 > Mario Teixeira
 > mjteixeira@yahoo.com