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From: jer@peora.UUCP (J. Eric Roskos)
Newsgroups: net.rec.photo
Subject: Re: Slide film vs Color Neg. film
Message-ID: <1775@peora.UUCP>
Date: Tue, 5-Nov-85 08:50:05 EST
Article-I.D.: peora.1775
Posted: Tue Nov  5 08:50:05 1985
Date-Received: Thu, 7-Nov-85 04:29:02 EST
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Organization: Perkin-Elmer SDC, Orlando, Fl.
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> The color rendition of color negative films can only be true if you shoot
> a grey scale on one of the frames on each roll so the lab knows what filter
> pack to use when printing.  All color negatives I have seen have an
> orange mask and need a strong compensating mask when printing, but in
> addition need tweeking to make white truly white.

I must admit that I have come to have doubts even about the need for distinct
color compensations among prints made from the same batch of film on the
same paper.  For a long time I used a color analyzer, with a photograph
of a Unicolor grey card on each roll, to get the color just right.  This
worked fine, but soon I found that all the photographs made in the daylight
on Vericolor III film printed on paper from the same box had the same
color correction.  Variations occurred for photographs made in the early
dawn or late evening, but it is debatable whether these should be corrected.
I had a photograph of a sunrise over the Atlantic Ocean which bothered me
for awhile, because the sky was green; so I went to some trouble to
color correct it to have a normal "blue" sky.  However, later I saw another
sunrise, and realized the sky was green at that time of morning over the
ocean!

On the other hand, you can make photographs made in awful yellow light come
out fairly well (all things considered) with proper color correction.

> As you know, slides come out with as true a color as you are ever
> going to get.  In fact you can compare the print with the slide and
> see if the print is right.  You can never do that with a negative.

The "you can compare your prints to the slides" seems to be the current
justification Herb Keppler gives for his anti-print editorial position in
Popular or Modern Photography magazine (I have some trouble telling those
two apart, except that Modern has more trustworthy ads).  However, this
assumes the colors were right on the slide in the first place... and how
do you compare a slide with a print, anyway?

> 2:  The slide film has better latitude and contrast range.

Neither of these is correct.  Print film has a lower contrast than slide
film, allowing it to capture a wider range of luminances in the original
subject (this also gives "wide exposure latitude").
-- 
Shyy-Anzr:  J. Eric Roskos
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