Temperature Compensation with Dew Heater

General
1

Greetings,

I am fairly new to SGP and am still learning the ropes. I got a new Moonlite focuser recently and it is performing well. The quesiton I have is regarding temperature compensation to trigger autofocusing. If I am not mistaken, one of the reasons to do temperature compensation is related to the contraction of the glass in the lens more than expansion or contraction of the OTA. Of course, I may be totally incorrect here.

If I have dew heaters keeping the lenses warm, but my temp sensor is monitoring the ambient air temperature, won’t the temp compensation triggered focuser be performed even though the lens temp may not have changed anywhere near what the change is at the focuser?

Thanks

Tom

2

Iam - in practice this should not be an issue. The temp sensor will be mounted near the motor or module and does not care about the optics. The optics will still change their temperature in line with the ambient conditions, maybe tracking a fraction above from the dew heater. The key thing is that it is a change that triggers AF. The AF routine takes care of the absolute focus position.