Pentax 67 shutter release?

Could a Pentax 67 (not 6x7 or 67 II) owner tell me, whether it is normal for the shutter to close immediately when the shutter release button is released? For example, if I choose 1 second exposure time, I need to hold the button down for the duration of the exposure, just like on a Hasselblad. Manual does not mention this, and the older 6x7 body does not do this - on that one, even if I press the button instantaneously, shutter will be open for the full one-second time.

I'm trying to figure out whether the body is OK or not.

There should be no need to hold down the shutter for a 1 second exposure if you have selected '1' on the shutter speed dial. If however the dial is set to B or X, that is a different matter, and the timing is up to you.

If a shutter speed does not work, it may indicate dirt or something interfering with the contact plate as part of the shutter speed mechanism under the top plate. All Pentax 6x7 models (those designated Asahi Pentax 6x7) vand to a lesser but no less potential extent, the "newer" (1992) 67 bodies are quite old, will have seen at one time or another heavy professional use and can be expected to develop faults over time due either to their age or neglect through long term storage and inactivity (of which leaving the shutter speed dial on any speed other than X or B for an extended period of time is one form of neglect).

Check also the the indexing nib is engaged with actual shutter speeds marked rather than 'freewheeling' (disengaged, as occurs normally when the TTL prism is removed/reassembled and the nib requires realigning).

Thank you. This one does not have a TTL prism, and the shutter times are actually very accurate - but only if I keep the button pressed. If I let go of it, shutter closes immediately.

I'm afraid it's service manual time for this one.

Try the owners manual before the service manual.

That's the first place I looked. Could not find a mention of this anywhere in it.

I usually ask on the forums either as a last resort or for a confirmation, not because of laziness.

onre said:

That's the first place I looked. Could not find a mention of this anywhere in it.

I usually ask on the forums either as a last resort or for a confirmation, not because of laziness.

Click to expand...

Didn't mean to bemoan the obvious, just sometimes people may miss a sentence. I tend
to do it all too frequently. Sorry.

John Koehrer said:

Didn't mean to bemoan the obvious, just sometimes people may miss a sentence. I tend
to do it all too frequently. Sorry.

Click to expand...

Absolutely no need to apologize. Reading my post again, it seems rather blunt. I didn't mean it that way.

Talking of the original problem, I only have the service manual for 6x7 model, which may or may not be similar. Looking at the schematic of the trigger circuit, I'm at a loss. My best guess would be shorted TR4 transistor.