[Nick Rowland]

Hi,

Does any have the shutter speed adjustment tolerances for a Spotmatic SPII please? The service book has the procedure and says to adjust within tolerance but I can't see what the tolerance range is.

I can adjust to what I consider acceptable but would like to adjust to factory spec if at all possible.

Thanks
Nick

[stevebrot]

Does any have the shutter speed adjustment tolerances for a Spotmatic SPII please?

I don't have a specification reference, but I can refer you to the copy of the Spotmatic manual available from Pentax Manuals:

Pentax Manuals | Service Manuals (Get the Pentax one from the link third from the top.)

In that manual, most timings have a tolerance range indicated and where that is missing, I would assume using precision appropriate to the value in the text (+/- 0.5ms ?) would be adequate. Out of curiosity, how are you timing the shutter?


Steve

[Nick Rowland]

Thanks Steve, I can't see a tolerance range quoted only millisecond equivalents, unless I can't see the wood for the trees. I have a generic chart which gives a range e.g. 1/1000 should be acceptable between 0.70 and 1.30 milliseconds, I may use that if getting spot on is impossible.

I'm using a Phochron XA tester with the twin curtain sensor as it gives 1st and 2nd curtain readings. This is the link Phochron XA- hand held shutter evaluation

It works well and you can self check the calibration too. It will work with any camera as long as you can get to the back of the camera, some older rangefinders bottom load so they can't be checked without disassembly.

Nick

[stevebrot]

Thanks Steve, I can't see a tolerance range quoted only millisecond equivalents, unless I can't see the wood for the trees. I have a generic chart which gives a range e.g. 1/1000 should be acceptable between 0.70 and 1.30 milliseconds, I may use that if getting spot on is impossible.

You have to read the text. See the curtain speed section. It appears your chart agrees with the manual. That tester looks pretty cool. Thanks for the link.


Steve

[Aaron28]

Phochron XA tester with the twin curtain sensor as it gives 1st and 2nd curtain readings.

neat!! reckon that is a touch better than my ears!

[Nick Rowland]

You have to read the text. See the curtain speed section. It appears your chart agrees with the manual. That tester looks pretty cool. Thanks for the link.


Steve

I must be blind Steve, I have read from page 27 onward and still can't see where the tolerances are quoted.

---------- Post added 02-29-20 at 12:57 AM ----------

neat!! reckon that is a touch better than my ears!

It's a great piece of kit. You really need to make up a jig to hold the camera and light source, though. A few folk seem to have made the jig from lego