From: jay@metran.UUCP (Jay Ts)
Newsgroups: rec.photo
Subject: Re: Hasselblad Film Flatness
Date: 16 Dec 92 01:38:08 GMT
Organization: Metran Technology, Tampa, Florida

accwai@math.uwaterloo.ca (Andy Wai) writes:
: In article <335@metran.UUCP> jay@metran.UUCP (Jay Ts) writes:
: >kfitzsim@magnus.acs.ohio-state.edu (Kevin Fitzsimons) writes:
: >:First of all, I don't see how you could "see" the difference in sharpness of 
: >:different cameras/lenses in magazine photos.
: >
: >Apparently, you are not a very critical viewer.  Or maybe you read the
: >wrong magazines :-)
: 
: Well, look at the photos in some magazines and compare them with some
: of your best shots.  I think it will soon became quite obvious that
: the magazines don't even come close to what a good slide or print can do.

That is already obvious, but if you enlarge 35mm to 8x10", and a 6x7
to 8x10", the difference is clear.  (Assuming good technique throughout.)
Lithography may not equal a photographic print in resolution (or tonal
range), but it can also show that difference.  I just checked a B&W photo
in Shutterbug, and it is screened at 5 lines/mm.  It is printed on the page
7x9", which would have been about a 7x enlargement from 35mm and was only
a 3x enlargement from 6x7 cm format.  (I am referring to the photo on page
16 of the Dec 92 Shutterbug.)  If you think that the same detail could be
produced with 35mm, I suggest you look around and find a magazine photo
taken with any brand of 35mm camera that shows the same kind of detail
(well-resolved whiskers and facial features and clearly present gun stuck
in the belt of Popcorn Sutton).

If I tried really hard, I might be able to do it in 35mm, using a Nikkor
macro lens and Technical Pan film and overall good technique.  However,
getting this kind of quality is very difficult in 35mm is easy in 6x7.

With a screen size of 5 lines/mm and an enlargement of 7x, this is
roughly equivalent to 35 lines/mm at the 35mm film plane, which is
dangerously close to the resolution of many 35mm camera/film systems.
That is, there is no good assurance that the limit on quality in the
final result comes completely from the screening and printing process.

I still don't understand why I feel that photos done with Hasselblads
are less sharp than those done with Pentax 6x7 or other medium format
(because both should do so much better than magazine reproduction, as
you suggest) but one email message suggested that it may be because some
Hasselblad lenses (including the standard" 90mm) are not as sharp as
others.  And then there's the Hasselblad soft focus lenses...  This in
combination with the photo being cropped to rectangular format may be
mostly what does it.  From the Hasselblad-made photos I often get the
impression of "Sharper than 35mm, but not as sharp as 6x7" -- more like
the 645 stuff I get from my 50 year-old Zeiss Super Ikonta.

: I think it's under the ideal condition that the differences between cameras,
: lenses, etc become apparent.
: For most people, it's very difficult if not
: total impossible to shoot under those ideal conditions and things become a
: lot less clear cut.

I have been refining my technique to make the camera system I use be the
main limiting factor.  It's not really very hard to do.

: Try comparing the stuff you normally shoot and the tests
: you make under ideal conditions and see how consistently you can come close
: to the level of your tests.

I do.  That is how I finally came to the decision to retire my Olympus
equipment!

: P.S. I'm a studio still life guy.  I shoot under close to ideal conditions.
:      So there :-)

So you shoot close-ups?  To me, that's no where near ideal!  First, you must
have a macro lens, that is made for close focussing.  Normal lenses lose out
when close-focussed.  Then, if there is any depth to your subject, your
lens's plane of focus passes though only a small part of it, and you have
only depth-of-field to reduce the blurs in the rest of the image.  Another
loss.  It is in fact, very difficult to get good sharpness across the
film plane when doing most product or still-life photography with anything
less than large format, where the camera movements can be used to match the
plane of focus to the subject as much as possible.  That is why practically
every full-page product shot you can find in magazines was done in large
format.  Study these carefully and you will be able to figure it out.
(Try a fashion magazine, like Elle; I find these to be the most fun!)
-- 
Jay Ts
uucp mail: uunet!myrddin!tscs!metran!jay
phone: (813) 979-9169