P3D Re: 3 red dots

[Brian Reynolds <reynolds@xxxxxxxxx>]

George Themelis wrote:
[George explains the three dot system on the Realist]
> 
> Another alternative of course would be to carry your digital
> spot meter and your programmable calculator or laptop, but
> that's an entirely different approach to this subject...
> 

When I read that I chuckled.  One of my biggest reasons for doing
photography of any kind is as a means of relaxing, getting away from
the office and computers.  But then I thought about my trip to Old
Rhinebeck Aerodrome a few weeks ago.

I wanted to take some stereo pairs of their aircraft (various original
and reproduction WWI and earlier planes that they fly every weekend
during their airshow season) with my Sputnik.  I find pre-WWII
aircraft to be good stereoscopic subjects because you get a better
feel for the rigging of the aircraft.  You can see how various wires
are routed and what they do.  As a model builder I get frustrated by
flat photos and plans where the rigging becomes a jumble.

Previously I had a poor showing at Rhinebeck with the Sputnik.
Handholding and focusing with the viewer I wound up with only one
really sharp pair of their Sopwith Camel.

This time I had the camera on my tripod so I would be able to slow
down and think about what I was doing.  But there were still the
focusing and exposure problems.  I took out my Pentax digital
spotmeter (which I had been using earlier in the week with my 4x5
Speed Graphic) and metered the grass on the airstrip to get a shutter
setting for f/16.  Then I tried to use my ground glass focusing loupe
to get a better view through the viewfinder.  Unfortunately all it
showed me was that the grain on the ground spot of the viewfinder was
really too coarse to focus with.  I decided to try using the
hyperfocal distance.  The Sputnik has a red spot on the focus scale,
but (as George pointed out above) I realized that it was probably set
for an apeture used with the slower films available when the Sputnik
was manufactured.  I don't usually use hyperfocal distances so I
didn't have a table handy for this camera.  Luckily I had my Palm IIIx
with Robert Wheeler's vade mecum program.  I entered my lens focal
length, aperture, film format, and print size and calculated a
hyperfocal distance.

On the two rolls I shot (12 pairs total) only four pairs have any
serious problems.  One pair is blank (better to wind past unused film
than to ruin two shots by double exposure), one pair (which I've
mounted) has a fence too close to view, and the remaining two
unmounted pairs also have a foreground fence so I haven't bothered to
mount them yet.  Not being focused on the main subject they aren't as
sharp as they could be, but they are acceptable.

Even when you try and avoid modern electronics and digital gadgets
they can come in handy.

-- 
Brian Reynolds                  | "Dee Dee!  Don't touch that button!"
reynolds@xxxxxxxxx              | "Oooh!"
http://www.panix.com/~reynolds  |    -- Dexter and Dee Dee
NAR# 54438                      |       "Dexter's Laboratory"