Niche feature request: derive focuser temperature from camera temperature

[swizzlr]

I have an electronic focuser with no temperature sensor. My guide camera, however, does report its chip temperature, and given that it is uncooled, is a fair approximation for ambient temperature. Would you be willing to allow me to contribute code to make this possible?

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tom

[Dale Ghent]

It being uncooled does not mean it is recording the ambient air temperature. It is simply the temperature of the sensor, which is going to not reflect the ambient air temperature at all. It is generating its own heat inside an enclosed body.

[swizzlr]

This is true! However I suspect that it would reach a thermal equilibrium with ambient while looping, thus a change of one degree Celsius could in fact reflect a change in ambient conditions. I recognize this is extremely niche however, so if you concerned it might be a support burden I’m happy to close this request.

[Dale Ghent]

Also it is impossible for NINA to get any info from the guide camera as the guide camera is being accessed by PHD2, and this access is exclusive to it.

[Ralf]

Hello Dale,
I am new here, but an enthusiastic user of NINA and its great features since about 6 months now.
I have also an electronic focuser like tom without a temperature sensor. Would it be possible to use the temperature information from the Openweathermap information instead. According to my experience this information is fairly accurate.

Have a nice weekend

Regards Ralf

[Stefan B]

The camera temperature is not a reliable metric for focus shifts. Sensors heat up during exposures, temperature probes are not necessarily reflecting ambient temperatures etc. Focuser temperature probes are often having a metallic cylinder shape that you can attach to the scope so it is having a similar temperature as your telescope and reflects that in the best possible way. A shift in ambient temperature also does not reflect the tempreature change of your telescope reliably as the scope might react slower to that change and would not have shifted its focus just yet. Therefore the only reliable probe is that of the focuser. There are other triggers for Autofocus available, e.g. time based or HFR based that will work better in case you have no reliable source.