QHY268M & QHY268C Users Thread (Please share your knowledge and tips)

[Stuart1971]

22 minutes ago, tomato said:

Yes, +1 for Bern at Modern Astronomy, he selflessly pointed me in the right direction 10 years ago when I had a wad of cash and not much idea.

As for the errant temp control on my camera, I took it off the scope, brought it in the house this morning and let it warm up to ambient as it was still 0 deg C in the dome. I powered it up with the QHY supplied 12V power supply, connected to EZCAP and wouldn't you know it, the temp control is working fine! It cooled to the set point, would warm back up when I raised the set point and then cool back down when I lowered it, all the values making sense.

I warmed it back up to+5 deg C then connected to NINA, all good except for this short lived spike in cooler power:

It quickly recovered, and continued cooling to the set pt and is controlling rock steady from then on. I have seen a couple of these spikes in the past, anybody else  seen them?

So, is it my dome PS? I doubt it, all the other kit runs off it OK and I've never seen a problem with this camera before or the QHY268M for that matter. OK the camera started off at a positive temperature this morning, rather then -1 or 0 deg C in the dome, but the camera has seen these conditions several times in the past without a problem. I'll put it back on the scope now and see how it behaves...

 

Well, first of all great news…👍🏻

Secondly,  yes I get those spikes too every now and again, but never really taken much notice, other than thinking at the time, hmm why has it done that, and then swiftly forgotten about it…

Sounds odd I know, but sometimes electrical items just like to be completely unplugged from anything and left for a few mins, I have to do this every so often with things in the house , like my Skybox, and Wi-Fi router, and it’s just to drain any static out of the electrical system which can cause errors…so why should an Astro cam be any different really….🤷🏼‍♂️ just a thought…

Edited January 16 by Stuart1971

[tomato]

Maybe, the only other condition that is new is that the current spell of cold weather is probably the longest my set up has experienced since the dome was constructed. Not sure why that should be an issue, but it is an observation. I sincerely hope the camera now behaves, I could have two good nights before the moon gets in the way.

[Stuart1971]

The next two nights look really good for me too…🤞🏻🤞🏻

[assouptro]

1 hour ago, tomato said:

Yes, +1 for Bern at Modern Astronomy, he selflessly pointed me in the right direction 10 years ago when I had a wad of cash and not much idea.

As for the errant temp control on my camera, I took it off the scope, brought it in the house this morning and let it warm up to ambient as it was still 0 deg C in the dome. I powered it up with the QHY supplied 12V power supply, connected to EZCAP and wouldn't you know it, the temp control is working fine! It cooled to the set point, would warm back up when I raised the set point and then cool back down when I lowered it, all the values making sense.

I warmed it back up to+5 deg C then connected to NINA, all good except for this short lived spike in cooler power:

It quickly recovered, and continued cooling to the set pt and is controlling rock steady from then on. I have seen a couple of these spikes in the past, anybody else  seen them?

So, is it my dome PS? I doubt it, all the other kit runs off it OK and I've never seen a problem with this camera before or the QHY268M for that matter. OK the camera started off at a positive temperature this morning, rather then -1 or 0 deg C in the dome, but the camera has seen these conditions several times in the past without a problem. I'll put it back on the scope now and see how it behaves...

 

I’ve seen spikes in the cooling power similar to your graph 

cheers 

Bryan 

[tomato]

Still not out of the woods yet...

With the camera back on the scope and in the dome (ambient temp +5 deg C) I set it to cool to -10 deg C through NINA. This it did but without apparently  any cooler power being required? I set it looping on 10 sec exposures, the cooler kicked in at 1-2% to keep it at -10 deg C with this additional thermal load. I then set the camera to warm up, but with the cooler already apparently at 0%, the temp stayed constant at -10 deg C.

Assuming the supply voltages are the same (and I adjusted the dome supply to match the QHY PS output) then the only change from when it was working on the bench is the 10 degree difference in ambient temperature? I've relayed all of this to QHY to see what they make of it.

[Stuart1971]

26 minutes ago, tomato said:

Still not out of the woods yet...

With the camera back on the scope and in the dome (ambient temp +5 deg C) I set it to cool to -10 deg C through NINA. This it did but without apparently  any cooler power being required? I set it looping on 10 sec exposures, the cooler kicked in at 1-2% to keep it at -10 deg C with this additional thermal load. I then set the camera to warm up, but with the cooler already apparently at 0%, the temp stayed constant at -10 deg C.

Assuming the supply voltages are the same (and I adjusted the dome supply to match the QHY PS output) then the only change from when it was working on the bench is the 10 degree difference in ambient temperature? I've relayed all of this to QHY to see what they make of it.

Which version of NINA are you using, and have you tried with any other software to run the camera and cool..?

[tomato]

NINA Version 2.3. I tried it out in the field with EZCAP, it displayed the same behaviour as with NINA. With the dual rig it would get a bit messy if the scopes were running different software, and I'd be curious to know why it has stopped working when I didn't change anything apart from putting it out in the cold again.

[Stuart1971]

1 minute ago, tomato said:

NINA Version 2.3. I tried it out in the field with EZCAP, it displayed the same behaviour as with NINA. With the dual rig it would get a bit messy if the scopes were running different software, and I'd be curious to know why it has stopped working when I didn't change anything apart from putting it out in the cold again.

Ok, I was just thinking more just to test to rule out any software issues not to run it like that all the time…but sounds like it’s not that anyway… 

 

[Richard_]

Daft questions, but did you try using the same USB cable as you did when testing inside and are you using the same USB limit values in both versions of NINA? 

[tomato]

I used the same laptop and hence NINA version for the bench test as I use in dome, so no change there. I did however use a different USB cable to plug the camera directly into the laptop for the test, when in use the cable goes through a powered hub and a 5 metre powered USB lead before connecting to the laptop. Could a deterioration in the USB connectivity cause the kind of issues I have been experiencing? Easy to test by plugging the laptop directly into camera in the dome, the promised clear skies have not yet appeared in my location so I could give this a try.

[Richard_]

32 minutes ago, tomato said:

I used the same laptop and hence NINA version for the bench test as I use in dome, so no change there. I did however use a different USB cable to plug the camera directly into the laptop for the test, when in use the cable goes through a powered hub and a 5 metre powered USB lead before connecting to the laptop. Could a deterioration in the USB connectivity cause the kind of issues I have been experiencing? Easy to test by plugging the laptop directly into camera in the dome, the promised clear skies have not yet appeared in my location so I could give this a try.

It sounds like the power supply works fine, but since NINA was only reporting weird values when plugged in outside, I suspect that data was perhaps not being transferred between camera and PC with full integrity. 

If you've had success with longer length USB 3.0 cables in the past, then perhaps they have degraded over time. 

However, if this is a newly introduced cable, then see if you can swap this out for a 3m cable. According to Pegasus, that is the maximum length cable you should use for USB 3.0 cables. Pegasus also state the following:

Humidity, particularly in conjunction with low temperatures, can gradually deteriorate the quality of USB cables over time. Numerous reports have highlighted instances where long USB cables initially operated without issue but developed problems such as random USB connectivity disconnects or packet losses after prolonged exposure to high humidity conditions.

https://pegasusastro.com/cable-management-recommendations/

Give a different USB cable a try and see if that works for you! 

Edited January 16 by Richard_
Added "with integrity"

[tomato]

Thanks for the tip. Since installation in 2019, I have had to replace one of the long run USB cables, although this failed totally, thankfully it didn’t slowly degrade. The problem camera is currently connected via the other old, original cable.🤔

[gorann]

Can anyone explain why USB cables are such sensitive devices and why they fail us repeatedly?

Edited January 16 by gorann

[assouptro]

4 minutes ago, gorann said:

Can anyone explain why USB cables are such sensitive devices and why they fail us repeatedly?

Mass production at the lowest cost I guess? 
if you had one made by hand with the best materials (if that was a thing!) it would probably work better and last a lot longer? 

[tomato]

I used  a short cable direct to the laptop in the dome, this made no difference. 
 

It’s almost as if the camera cooling set pt is being offset by the ambient temperature. I understand on start up the camera auto cools to 0 deg C but what if the camera is already at this temperature, does the camera cool down further by the same amount? QHY might be thinking along the same lines as they are asking me to check what happens when the cooler is turned off both indoors and outdoors.

Oh, and it looks like last night I managed to fry my Rising Cam IMX571 camera, I was a bit shaky plugging the power lead in at it looks like I somehow momentarily put a reverse polarity 12v into the camera!😱An odour of burning and a whiff of smoke followed,  and it won’t connect anymore. Lesson learned, plug in then switch on.

At this rate I’ll have to dig out my G2-8300.😊

[Richard_]

Ah @tomato, so sorry to hear about that. It sounds like you've used up all your bad luck for the year already. I hope you have nothing but good luck from here on in. 

[tomato]

Thanks, I’m still not sure what I did to cause a short when plugging in the power, TBH I can’t really see how the plug could have put reverse polarity into the socket on the camera, but something has happened, that’s for sure.

[Stuart1971]

15 minutes ago, tomato said:

Thanks, I’m still not sure what I did to cause a short when plugging in the power, TBH I can’t really see how the plug could have put reverse polarity into the socket on the camera, but something has happened, that’s for sure.

Yes, those were my thoughts, it’s nigh on impossible to touch the inner and outer parts of the jack plug incorrectly….

Maybe something has shorted inside the camera where the socket is soldered on to the board…

but as @Richard_ says, you have certainly had you share of bad luck..☹️

Edited January 17 by Stuart1971

[tomato]

It will be on @Tomatobro’s work bench on Friday, I’ll let you know what we find.

[tomato]

Back on the QHY 268c cooling topic, QHY have asked what happens when the camera is allowed to warm up indoors (ambient temp ~15 deg C) and outdoors (ambient temp ~ 0 deg C).

Indoors I cooled the sensor to -10 deg C, cooler power at 13% to maintain this temperature. With the cooler off, the sensor temp rose uniformly back up to 0 deg C, at this point I terminated the test:

Outdoors  I cooled to -10 deg C, the camera reached this temperature and continued to cool but with 0% cooler power displayed. When it reached -14 deg C I switched to manual and turn the cooler off. The camera cooled a bit quicker to -20 deg C and then slowly warmed up but seemed to stabilise at -19 deg 😄

I'll send this info to QHY, to see what they make of it.

[tomato]

Here is QHY’s response to the above info:

Hello，Yes, judging from your latest test, the temperature control is normal, but outdoors, it may be that the heat dissipation effect is too good, causing the temperature inside the sealed camera compartment to be lower than the ambient temperature, which leads to this difference.

Not quite sure where this leaves me, the camera cooling is definitely not operating correctly, as it used to operate OK at low temperatures and my QHY268mono still does.

Not sure I want the faff and expense of returning it to QHY over this issue though, but last night it said the sensor was at -38 deg C with no cooling, maybe I’ll wait for the weather to warm up and see how it controls then.

[tomato]

The other action could be to reinstall the firmware, anybody done this?

[Stuart1971]

I managed another 9 hour session last night from 18:00 until 3:00 am, and got SHO data in 3 targets.

Everything worked flawlessly again which I was happy about after a few months of disconnect issues with my CEM70 mount, I finally got it sorted…

‘It was cold and the QHY268 stayed at -10 with zero cooler power needed yet it was only -5 outside, which was odd, and the camera even dropped to -11 for an hour or so, again with zero cooler power, I started to think of @tomato and his issues, but then the outside temp came up to about -4 and the cooler power kicked in on 1.6% to keep the camera at -10, so I assume all was good…

Not sure how the camera stayed at pretty much exactly -10 with zero cooler power when the outside temp was almost 5 degrees warmer…🤷🏼‍♂️ ? and as I said, at one point the camera dropped to -11

It does seem as if these cameras are a bit quirky in the colder temps

[Stuart1971]

5 minutes ago, tomato said:

The other action could be to reinstall the firmware, anybody done this?

No I haven’t ever tried this, I am still using what came with the camera, old firmware and old USB driver, but what I will say is that AFAIK the firmware is updated along with the USB driver, and there was a firmware update for the cooling on these cameras in the last 6 months I believe 

[tomato]

I’ve looked on the QHY website there is a specific procedure to update the firmware, and you don’t want a power interruption while you are doing it.

Thinking back I’m sure there was a big cooling power spike on this camera during a routine cool down and it has displayed this behaviour ever since. It reminds me of the early days of video recorders, on the problem page of one of the magazines a reader said his timer on the VCR had stopped working, the magazine’s tech guru said it had probably been hit by a stray neutrino.☺️