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on Jul 3, 2015 9:22:02 GMT
Last Edit: Jul 3, 2015 9:22:35 GMT by docyashi
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Status: Long, long time Contax and Yashica user; glad to be here and hope to contribute.
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on Jul 3, 2015 10:18:54 GMT
Posted: Jul 3, 2015 10:18:54 GMT
The Contax CGCM cameras, based on the 137MD, come in a wide variety of types.
Although not obvious from this photograph, nearly all CGCMs require an external power supply which usually involves a 12-pin DIN connector which connects via a socket in the base or at the back of the base. Most of them have no mirror assembly as they are intended for use with the likes of oscilloscopes which do not require metering or focusing - this is one of the less common types with the mirror still in place. I have never come across a CGCM with any metering capability though some may exist. They usually fire at a single, predetermined shutter speed - usually around 1:125s. They have little use outside the laboratories which are their natural homes - the biggest problem is powering them as the bespoke connectors need to be stripped to isolate the pins that carry the power and that fire the shutter as the switch on the camera's top plate is usually a simple ON/OFF - the shutter is fired externally.
I have had one of mine modified to act as a microscope camera, operating from an external box using six 1.5v C batteries, connected to the scope via the Yashica Adapter. The others are just nice paper-weights...
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on Jul 3, 2015 13:42:17 GMT
Posted: Jul 3, 2015 13:42:17 GMT
Wouldn't the shutter speed have to be synced to the refresh rate of the oscilloscope screen?
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on Jul 3, 2015 16:32:53 GMT
Posted: Jul 3, 2015 16:32:53 GMT
Thanks biggles, great explanation.  |
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Status: Long, long time Contax and Yashica user; glad to be here and hope to contribute.
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on Jul 3, 2015 18:30:50 GMT
Posted: Jul 3, 2015 18:30:50 GMT
Wouldn't the shutter speed have to be synced to the refresh rate of the oscilloscope screen? Quite right - those that were intended for use with oscilloscopes would need to have that capability and that was usually handled by a Prontor shutter contained in the adapter that linked the camera to the scope. I have five CGCMs and one M35W - when tested 3 of the CGCMs that had no mirror operated at a fixed speed of just under 1:125s. The other two relied on the external shutter. |
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