Basic information:
The Olympus OM-10 is an ideal
SLR camera for a beginner on a budget. Prices are very reasonable for used bodies (they went out of production long ago). OM-fit lenses are readily available.
Features:
Building a manual adapter:
The manual adapter is a simple
resistive device which plugs into a
mini-jack on the front of the body. The following table gives resistor values against
exposure time:
Exposure Value
1000 7k6
500 15k2
250 30k3
125 64k0
60 121k6
30 249k5
15 494k0
8 972k0
4 1M96
2 3M91
1 7M92
The
design of a simple manual adapter, giving between 1/1000 and 1/15 plus bulb exposures follows:
Jack ----------------------------+
^---+ |
| __ |
| o---o o---|
+---/\/---o S2 /
R1 \ o--------->\ R2
S1 /
R1 = 8k
protective resistor
R2 = 500k
log pot
S1 =
SPDT toggle switch
S2 =
Push-to-make momentary switch
This gives a
switchable system. In one mode, the
potentiometer controls the exposure, between 1/1000 and 1/15; in the other, the shutter opens on pressing the
shutter release, and then closes on pressing the momentary switch.