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ASCOMInitiative / ConformU

ConformU is a cross-platform tool to validate that Alpaca Devices and ASCOM Drivers conform to the ASCOM interface specification. It supersedes the original Windows based Conform application.
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LastExposureDuration is not the same as image duration #8

Closed RReverser closed 1 year ago

RReverser commented 1 year ago

When trying to report an actual exposure duration, I'm getting ConformU test failure:

03:40:43.398 LastExposureDuration                ISSUE    LastExposureDuration is not the same as image duration: 2.0668501 2

I could simply set it to whatever user provided in duration field, but the ASCOM docs for this property say:

This may differ from the exposure time requested due to shutter latency, camera timing precision, etc.

Given that this is meant to be an actual exposure time including latency, I think ConformU should have some error tolerance in this test, similarly to how it already has error tolerance for LastExposureStartTime test.

Peter-Simpson commented 1 year ago

Hi Ingvar,

The LastExposureDuration test in ConformU has a 2% tolerance, so values in the range 1.96 to 2.04 seconds are accepted for a 2 second exposure. To date, I’ve not had reports from other people that this tolerance is too tight.

If the time difference from the expected value is essentially a constant offset, you should be able to get your device to pass by configuring a longer test exposure time on ConformU’s camera settings page.

Hope this helps,

Best wishes, Peter

RReverser commented 1 year ago

Ah, thanks, sounds good. The messaging gave me an impression that it was doing an exact comparison.

I think longer exposure in settings should cover it for me.