Are there any benefits to getting the ASIair temperature sensor?

[Swoop1]

What does it do? (apart from sensing the temperature.......😉)

 

[Elp]

I'd assume it's to work alongside their EAF so it'll refocus automatically after a certain temperature change. It's an issue when imaging though I've never refocused during a session.

Edited August 9 by Elp

[Budgie1]

I can't see a ZWO temp sensor specifically for the ASIAir, there's one for the EAF, but this won't fit the ASIAir as the connection is different. Having said that, I think the ASIAir will monitor the sensor data from the EAF and use it as @Elp describes.

I've had a couple of sessions where I've noticed the focus drifting during the session, but I couldn't say it was definitely due the air temperature.

My Pegasus Pocket Power Box Advance has a temp sensor, which is used to measure the Relative Humidity (RH) for the dew heaters. The higher the RH, the more power it supplies to the dew heaters. I think you can also set it up for a focus routine as well, but I don't use it.

[saac]

31 minutes ago, Budgie1 said:

I can't see a ZWO temp sensor specifically for the ASIAir, there's one for the EAF, but this won't fit the ASIAir as the connection is different. Having said that, I think the ASIAir will monitor the sensor data from the EAF and use it as @Elp describes.

I've had a couple of sessions where I've noticed the focus drifting during the session, but I couldn't say it was definitely due the air temperature.

My Pegasus Pocket Power Box Advance has a temp sensor, which is used to measure the Relative Humidity (RH) for the dew heaters. The higher the RH, the more power it supplies to the dew heaters. I think you can also set it up for a focus routine as well, but I don't use it.

As above, the temp sensor is fitted to the EAF not the AsiAir. The AsiAir reads the temperature data via the connection from the EAF and will initiate a refocus pending the temperature change limits you have set in the menu. The AsiAir allows you to specify when to conduct a re focus routine, for example following a meridian flip or as discussed a change in temperature. The temperature sensor is fairly inexpensive and worthwhile if you experience significant temperature fluctuations during your imaging runs. 

Jim 

Edited August 9 by saac

[AstroMuni]

On 10/08/2024 at 00:14, saac said:

The AsiAir reads the temperature data via the connection from the EAF and will initiate a refocus pending the temperature change limits you have set in the menu.

Does the ASIAir allow you to add a weather station or Weather services?

I use Stellarmate and I use an OpenWeathermap driver to provide the temperature data for deciding when to refocus.

[saac]

6 minutes ago, AstroMuni said:

Does the ASIAir allow you to add a weather station or Weather services?

I use Stellarmate and I use an OpenWeathermap driver to provide the temperature data for deciding when to refocus.

No it doesn't offer that in any way. The temperature sensor is the only external environmental input. 

Jim  

Edited August 27 by saac

[tomato]

At the end of the day, you want to refocus if anything causes the FWHM to deteriorate (eg temp, sky elevation, focuser shift etc) so if the ASIAir enables you to do this then isn’t the temp probe a bit superfluous? Of course the refocus may not be able to fix all of these contributors but that’s about all you can do.

[ONIKKINEN]

47 minutes ago, tomato said:

At the end of the day, you want to refocus if anything causes the FWHM to deteriorate (eg temp, sky elevation, focuser shift etc) so if the ASIAir enables you to do this then isn’t the temp probe a bit superfluous? Of course the refocus may not be able to fix all of these contributors but that’s about all you can do.

I can think of a few scenarios where fwhm measuring is not as good as temps+fwhm. For example the target is low in the sky when starting the sequence and rises higher during the night, but temperatures also drop sharply. In this scenario fwhm should get better as the night progresses due to increased elevation, but focus goes off due to temperatures. If these 2 factors align nicely fwhm stays the same so there will be no refocus called by the software since fwhm didnt change. With the temp sensor added there would be a refocus and the resulting fwhm would now be better.

I am focusing with the mk1 standard edition thumb and index finger so suffer no such headaches, but the above scenario is not too uncommon with my imaging. I regularly see fwhm stay the same when those 2 factors align, but i know i should refocus because i have a good idea what the fwhm (HFR actually) should be.

Nitpick territory of course, im sure just using fwhm changes to refocus is good enough for most situations.

[tomato]

No, that is a valid scenario which as you say could mean you miss out on a valid focus improvement. With NINA you have a whole host of parameters to trigger a refocus, which would capture all of these eventualities, but I'm not sure if all of these options are available with the ASIAir.

In my experience in the UK we rarely get a night that is not blighted by passing cloud, which prompts frequent refocus operations, all to no avail.

[saac]

1 hour ago, tomato said:

At the end of the day, you want to refocus if anything causes the FWHM to deteriorate (eg temp, sky elevation, focuser shift etc) so if the ASIAir enables you to do this then isn’t the temp probe a bit superfluous? Of course the refocus may not be able to fix all of these contributors but that’s about all you can do.

I don't think it is superfluous at all it is simply there to re focus given a significant change in temperature. I have mine set to refocus with a 2 degree change in temperature and on meridian flip.  I shoot OSC so no filter changes as such mid imagining session. To date I haven't had any concerns at all with how focusing has been performing. I auto focus at the start of a run and leave it to itself, so far all has been well, keep it simple it just works.  

Jim 

Edited August 27 by saac

[Tony Acorn]

When I was a lad (and god was in short trousers), "In my experience in the UK we rarely get a night that is not blighted by passing cloud" we were only blesse with Passing Cloud when we had money to burn at the local tobacconist! 😂

Back to the OP, I seem to be ok without the ASi temperature sensor in my rig* although I have only managed around 150 minutes of continuous imaging so far. If the temperature gradients increase between start and end of sessions, the use of one may become necessary but I have dew heaters on my guide scope and the main scope which may mitigate.

* StellaMyra 80ED f/6.25, ASi 585MC, AE 50mm f/4 finder scope, ASi 120MM, ASi EAF, ASi AM3, ASiAir-Mini

[saac]

1 minute ago, Tony Acorn said:

If the temperature gradients increase between start and end of sessions, the use of one may become necessary but I have dew heaters on my guide scope and the main scope which may mitigate.

* StellaMyra 80ED f/6.25, ASi 585MC, AE 50mm f/4 finder scope, ASi 120MM, ASi EAF, ASi AM3, ASiAir-Mini

To be honest I think I have only ever noticed the Air interrupting an image run twice because of a temperature change to re focus. I think there are many other factors more likely to spoil an image session  - most likely clouds or poor seeing than temperature change  

I think dew control though is a separate issue. The Air is measuring air temperature because temperature has a direct impact on the refractive index of the air which in turn will change the focus conditions. Dew control isn't really a focusing issue though. 

Jim