Re: "Best" color slide film/color neg

[David Spellman <david@photopro.com>]

Gary Sellani wrote:

> I've always felt that slides had the best color accuracy. (OK, potential for
> the best color accuracy to keep the word demons off my back.)  If you use
> the higher speed slide films (Provia or Elite), the high contrast and low
> latitude problems are reduced somewhat, but not to the degree of print film.

    Provia, by the way, is not one of the films listed as having outstanding
color accuracy -- it is an "enhanced" color film akin to, but without quite the
cartoon boost of, Velvia. While I use EPP 100 for most of my product shooting,
it is also considered a slightly enhanced film compared to what most consider
the dean of accuracy, EPN.

> Print film is very forgiving, but the print process seems to be a random
> number generator. You can take multiple print photos and the sky will not be
> the same in any photo if the main elements of the scene are different.
> [Shoot a scene without people, then with people, and note how the sky isn't
> the same. I think the printers have computers that lock on flesh tones.

    There are several reasons that the sky will not be the same shade of blue.
One of them has to do with the polarization of the light that occurs naturally
in the sky. If you point one arm at the sun, and then put your arm out at a 90
degree angle to that direction, you can circumscribe a circle. The sky will be
the deepest blue along the line of that circle and lighter in other places.
Second, the amount of water vapor in the sky can lighten it considerably, while
more or less dust in the atmosphere can either deepen the blue or turn the sky
brown or yellowish. The blue of the sky will also obviously change depending on
the time of day and the angle of the sun.

    Print film isn't to blame -- you can actually do a pretty good job of
getting colorsYou'll  with the instruments that custom printers use these
days...

> I prefer slide film for keeping your images in order. [I'm sure you have the
> clear sheets with pockets to hold slides that you can put in binders.]

    While others prefer using proof sheets with their negs. This way, the
original neg doesn't have to come out of the box when you're searching for a
specific shot...


> Note that for print film, the lab compensates the exposure, which undoes
> your bracketing. This can be really annoying if you are trying to get a dark
> sky effect, such as shooting a lighthouse just after sunset. This is where
> it would be interesting to have a film scanner. I would like to know how
> much of the latitude is due to the print film and how much is due to the
> printing process.

    It's actually pretty easy to determine the latitude of a print film, and
photographers have done it for ages. It has to do with the same testing that
produces that characteristic "shoulder and toe" curve, and is done in a very
analog way (though it can be done more quickly with instruments, of course).
You don't need a film scanner to determine the "best" exposure, either. Have a
"true proof" sheet done. This is one in which the film is placed in strips on a
sheet of paper, and base density of the film is exposed to just barely match
the blackest black the paper will produce. If you have normal contrast in your
film development, your best exposure for the film/developer/paper combination
will be the one that looks best (not underexposed, not blown out) on the proof
sheet. You'll also be able to see exactly what your bracketing looks like.
    You may be interested to know that the "latitude" of the printing process
is going to change significantly in the one-hour photolab business as printers
replace their current machines with the new "digital" systems. You'll still
have your film processed in the usual way, and you'll still receive prints back
on photopaper, but in between will be different. Instead of exposing the print
film directly onto the paper through an optical system, your film will be
scanned, analyzed, and then digitally printed onto the photo paper. This will
allow some rudimentary sharpening, contrast control, etc. One of the main
beneficiaries of this process will be prints that are seriously underexposed,
and which would have been printed to a flat, murky middle grey -- these prints
can be enhanced to give more color and contrast (though shadow detail that
wasn't there won't be there in the print, of course), and will almost look
normal.


To keep this somewhat relevant to epson inkjets, I find the colors are more

> saturated when I print on my Epson 1200 than the colors in the original
> image. I use the saturation control in the print driver, but this isn't
> perfect. At the moment, I am settling for acceptable results, but not
> getting exceptional results.
>

     Saturation may not be your best control, here. You may have a lot more
contrast than you need, and this can produce what looks like oversaturated
results in print. You haven't mentioned if the colors seem more saturated than
what appears on your monitor.
    If you're using slide film, you'll always have more range of color than you
can reproduce on a reflective surface. In order to make a print from a slide,
you need to compress that range of colors. When you make a direct print on
photographic paper (Type R) from a slide, you'll find that almost always the
colors are super saturated and the shadow and highlight detail are lost. Most
printers use a technique called Unsharp Masking (YES!) that is designed to
reduce the contrast levels. The other option is to make an internegative on a
special very low contrast material and then print from that. You're going to
have the same situation with moving from a transparency (slide) to a print.
Most software has compensation built into it that will reduce the contrast
levels considerably to make allowances for the differences in range available
in a slide and in a print, but if your software doesn't take care of things
automatically, you need to adjust it yourself.

    david

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