P3D Twin Pentax SLRs

["Wladyslaw Reksc" <wlad@xxxxxxxxxxxxxxxxxx>]

I'm so behind in P3D reading that I even don't want to tell you exactly how
much. I just feel like I just jumped out of the jungle, it's so bad. So
please tolerate me if I say something that has been said already.

I started using my new camera set and thought that somebody might be
interested in my experience. It took me a bit of experimenting with this
photo hardware, so there is some ground for information reuse.

After shooting with FED for two years I became very upset with this camera
limitations. This pushed me to look for some better equipment. I heard
several people commented on choosing Canon Rebel SLR. I Looked at in a
store, but didn't fell it would be the best selection. Rebel is a bit too
big, especially that bulky battery compartment sticking out so much. Another
thing that made me uncomfortable with it was "non-standard" exposure setting
controls. What I mean by that is that manual exposure control is not set by
dedicated dials, i.e. separate selector for the shutter speed. I felt it was
important to have it to use it intuitively and quickly, when taking picture
requires fast reaction.

My choice was directed to Pentax ZX-M (it is called MZ-M in Canada). It is
really compact and very light (less then 500 g without batteries). It has an
integrated motor drive. The shutter speed dial is identical to older type
cameras. This later, in real life situations, became very handy, will tell
why in a moment. I opted to ignore auto-focus capabilities of that camera
and bought manual lenses for that model. I wanted to get 28 mm, but so far
was able to find only one (Ottawa is not the place you can get lots of photo
equipment). But I was lucky to obtain two 40 mm Pentax lenses (so called
"pancakes". The provide enough depth of field to almost make the setup work
as "focus-free" cameras. With f stops 8 and higher, everything is sharp from
2 meters to infinity. The only thing with those lenses is that MZ-M will
overexpose a bit. To compensate for that, automatically detected film speed
must be manually increased by one step manually, each time a new film is
loaded (e.g. 100 ASA film should be exposed with ASA 125 setting on the
camera).

OK, so now you know what was used. Time to tell how. Of course both cameras
are mounted on a bar, side by side. That gives the spacing between the
lenses around 140 mm. To "save" some money on those expensive camera
batteries, I decided to use Pentax battery packs (housing 4 AA batteries)
and mounted each camera on a its own pack, but only one pack was containing
the batteries - both cameras were powered from one source. It was just fine
when I was taking test shots using "finger" synchronization. Test pictures
were perfectly exposed, left and right were identical (at least for me), so
I was encouraged to invest more time and make the synchronized electrically.
MZ-M SLR has 3 contacts for an external release electric cable (those are
ground, measure, release). It took me a while to make it working. Each time
those 3 contacts on two cameras were connected in parallel, the shutters
started firing continuously. Using diodes to separate them didn't help. Only
after I used separate batteries for each camera, the problem disappeared. I
kept the cable with the diodes (was too lazy to remove them). With it I can
fire both cameras simultaneously if release button is pressed on one camera,
or only one camera fires, when pressed on another camera. A quick-and-dirty
experiment with bare 3 wires connecting two SRLs proved that diodes are not
needed, when each camera has it's own power supply.

I just returned from a one week trip where I exposed 6 pairs of slide films.
Some pictures contained quick moving elements (water fountains, flying
balls, airborne birds, running dogs). All of them were perfectly identical
on left and right images. So simultaneous releasing works great.

The last piece of information I have about MZ-Ms. This model is really fussy
when it comes to the flash light. I could not use my two generic flashes,
because, when charged, they caused cameras electronics malfunction (wrong
exposure readings, multiple shutter releases). I had to buy an original
Pentax flash. I install it on left camera, with both of them set to 1/60
(although a flash setting is 1/100). I don't know if it helps, but I hope it
gives more time for both cameras get the shutters open for the flash. On
about 30 pictures I took with a flash, 3 got a small dark stripe on the
bottom of the right image. Any suggestions how to fix that?

That would be it. If you have any other question, let me know.

Wlad


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