P3D Re: world of non-ortho

[gjw@xxxxxxxxxx (Gregory J. Wageman)]

John R. wrote:

>But seriously, I've seen a lot of stereo prints, and a relatively smaller
>number of stereo slides, and I don't notice any striking differences between
>the two. I would speculate that people who have mostly been exposed to
>slides may have developed a feeling of familiarity with that system, which
>causes them to feel more comfortable when viewing slides than when viewing
>prints. This would tend to skew the judgement of relative merit. I'm
>(hopefully) about to see how slides are precision-mounted - perhaps I can
>then try slide and print stereos of the same scenes, to further resolve
>my own views on the matter.

I've got a reasonable amount of experience with slides, and somewhat less
with prints, but enough I think to compare the two.

One significant difference is the fact that slides are often sharper than
prints because there is no printing step involved.  Assuming you know how
to focus your camera and use DOF properly, your slides will be sharp; the
photofinisher's quality control (or lack thereof) cannot affect this.
Your prints may or may not be, depending on how well focused the enlarger
is at the time they print your roll.

Also of importance is the speed and quality of the print film you use, as
well as the quality of the paper used for printing.  I think this should
be obvious, but while I have read many discussions here about how "grainy"
slide films faster than ASA XXX look (substitute your own personal
preference), I haven't seen the same discussion regarding color negative
film.  If you're using a "consumer" film like Kodak Gold 400, you won't
get anywhere near the same sharpness as with something like Kodak Royal
Gold 25 (which, by the way, produces wonderfully saturated, sharp prints
that come as close to rivaling my slides as I've been able to with prints).

The printmakers who are doing their own developing and enlarging really
have a leg up on those of us who have to rely on commercial services, as
they can take as much time and care with each print as they would like.

One final factor is color balance, which again is determined by the
printing step for negative film, but only by the film emulsion (and of
course the original lighting conditions) with slides.  This was very
dramatically illustrated to Susan and myself when we both photographed
the same cars at an antique car show, she with print film and I with
slide film.  The print of one car in particular, which had a deep
purple metallic paint with a "flame job" scheme around the radiator,
was faithfully reproduced by Velvia, while the print was decidedly
skewed from reality.  Not "bad", per se, but just not an accurate
representation of the original.

*Can* prints compete with slides in resolution?  I think so, definitely.
There's more than enough resolution available in the system, even given
the fact that a print is a second-generation image.  However given what
I think is probably the typical scenario (i.e. commercial developing and
printing), I think the odds are somewhat in favor of slides looking
sharper on average.

	-Greg W.




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