[Leica] Megabit hooey!

["Dante A. Stella" <dante@umich.edu>]

I have watched this whole debate about gigabit film from the sidelines.

What I am left with is, "so what if you can get 100/900lp/mm from a 35mm
camera."  To do it always means shooting at EI25, 12 or 6, losing most
if not all exposure latitude, and ending up with prints that can look a
touch flat.  This has been my observation with TP, and megabit no doubt
produces similar problems.

There really is no systematic penalty for using MF cameras when you want
to.  For example, Tri-X in 35mm looks like hell at any EI.  Not pretty,
and something you would only use if you needed it.  However, in 6x9, it
is a wonderful, warm film that has no visible grain (on the print).  And
you can contact print it and see everything that is going on.

For example, to reach any given result, going to 6x9 from 35mm allows
you to use film three times grainier (or, I guess faster), have lenses
with 1/3 the resolution, contact print and actually see the picture and
the overall effect, and so forth.  When you do the math, the "slower"
lens speeds in the MF cameras are not a liability.  You get commensurate
results with 6x4.5 and 6x7.

Consider that for your two stops (or even three) exposure gained in
using a fast film on a larger camera,

a 35/2 on a 35mm is speed- (and angle) equivalent to a 60/4 on a 6x4.5
(interestingly, the min focus distance is similar)

a 50/2 on a 35mm is equivalent to (or slower than) an angle-equivalent
100/3.5 on a 6x9 (one meter typical cf on both)

an 90/2 on a 35mm is a stop faster than a 180/5.6 on MF
but a 100/2.8 or a 105/2.5 is about the same speed

If your maximum print size is 16x20 (as most of us can realistically
expect to make), the quality benefits of pushed MF film (like TXP to
1250, or straightlining TMX in Rodinal to 400) will make medium-format
lenses effectively *faster* than 35mm ones of similar coverage.  If you
look at the pictorial side of my web site, you will see a lot of
pictures taken with TX @1250, which is not something you can do with
35mm.  You also pick up Tri-X Pro, which is a great film for the
Mediterranean and Verichrome Pan, which is a beautiful film never made
available in 35mm.

Also, in my observation, with 400-speed film, there is no difference in
the type of details the film can resolve (at the same magnification).
With 100-speed film, 35mm film can pick up slightly smaller stuff, but
not by much.  You also have to take into account how much 35mm has to be
enlarged.  Modern MF lenses are certainly better than 2/3 the resolution
of 35mm lenses.

Sure, there is a size/weight penalty.  But when you compare a Fuji GA645
collapsible with 60/4 to my M3 with 35/2, it is really a draw
weightwise, if not an edge to Fuji.  And the thickness of the two
cameras (for pocketing) is the same.