[MF3D.FORUM:615] Re: Thanks Paul

[Brian Reynolds <reynolds@xxxxxxxxx>]

Bill Glickman wrote:
> I have been contemplating this exact issue.  Maybe you can offer me
> some insight.  I have two M7's now, and my missing link is the
> inability to snap both shots at once when the camera spacing needs
> to be 65mm.  (Due to the cameras inability to get this close) I was
> wondering when shooting landscapes shots, how critical this
> is... From what you write above, it sounds like even the slightest
> leaf or branch being out of place will play havoc with ones ability
> to fuse subjects.  I kind of suspected this, but have no base for
> comparison, since I never had the ability to try this both ways.  Do
> you find that snapping both shots at once is critical some of the
> time, most of time or almost all the time?  Thats what I am trying
> to get the feel for....  Any input in this area would be very
> helpful...
> 

I started MF stereo with a pair of Lubitels TLRs on a flash bar
shooting landscapes in Ireland.  I find that having a base seperation
greater 65mm is better for landscapes and architecture.  With a 65mm
spacing everything is flat and you might as well not shoot stereo.
The cheap aluminum flash bracket I used with these cameras allowed me
to change the stereo base as I saw fit.  Minimum seperation is about
100mm.

> I can probably guess this dual firing is very critical.... if so,
> what are some recommendations on newer MF camers that can acheive
> the critical 65mm spacing, can be fired siumltaneously and also
> offer interchangeable lenses?  It seems most of the new box type
> cameras by Mamiya, Hassy, Rollei, Bronica, etc. are way to big,
> preventing the desired 65mm spacing.
> 

Firing the shutters is more important than the stereo base.  If you
take wide, sweeping landscapes I don't think you'll have much trouble
with synchronization unless there are animals (or people) in the
frame, or it is really windy.

I only decided to get a Sputnik (for the shutter synchronization) when
I started taking pictures that had people or the ocassional animal in
them.

> If I were to mount my two M7 80mm lenses on a view camera lens
> board, they still will not be 65mm apart, but can get to about 70mm.
> Will this extra 5mm spacing ruin the desired effect?  Or would it go
> un noticed as long as I am not shooting very close objects, like
> 3ft.  If this is feasible, I would consider putting 2 M7 mounts in a
> Toyo lens board, focus via the ground glass, and then insert a 6x12
> roll film holder (with a slight bit of modification) and get two 6x6
> chromes.  Of course I would need a light divider inside the bellows.
> I can link the shutters electronically.  I have considered using LF
> lenses, but they will not get much closer, and they do not seem as
> ideal as MF glass since the MTF curves on LF lenses are not
> optimized until f16 and higher, while MF glass is optimized at the
> wider and faster apertures... and speed seems a great advantage in
> MF 3d.
> 

Unless you already have the 6x12 back, it's probably easier and
cheaper to just shoot on 4x5 sheet film.  Also, many of the 6x12 backs
are a bit smaller than 6x12.

-- 
Brian Reynolds                  | "Dee Dee!  Don't touch that button!"
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http://www.panix.com/~reynolds  |    -- Dexter and Dee Dee
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