ASI071 MC Pro TEC Problems

ilparr

My new ASI01 MC Pro struggles to keep the camera below -20c and runs at 100 % doing so.

De-Icing is turned off and I have used ASICAP, SharpCAP and Sequence Generator Pro have all the latest drivers with no difference.

The camera is advertised as capable of -40 (qualified as -35 to -40) below ambient.

The first time I used it with air temperature round 10-12 c it fluctuated wildly and varied by 4 degrees during the session (17-21 with a Target of -25 downgraded to -22) and running at 100% the whole time.

So I then purchased a TemperHUM device to monitor the conditions while running darks under properly controlled and stable temperatures in a refrigerator. Under steady ambient conditions around 5 degrees the BEST I could get was -23 and it was running at 100%

After a long darks run in HDR mode the whole time it ended up at -19 degrees while still running at 100%

I repeated the test over two days and nothing changed.

I have friends with other lower end ZWO models who easily get -20 at around 50% with ambient around 5-7 degrees C

I can prepare a detailed analysis linking the TemperHum logs to the temperatures derived from the the images at the same time if necessary.

Is there a firmware update or other solution available that will get it to perform as advertised?

Thanks

Ian

ilparr

The lack of response leads me to think that the TEC is under-engineered for the larger chip and not simply faulty.

I hear crickets ....

katherine.tsai

How to get the best performance from your cooled camera

https://astronomy-imaging-camera.com/tutorials/how-to-get-the-best-performance-from-your-cooled-camera.html

ilparr

Thanks for that

The only relevant bit in my case was ...

The cooler runs effectively in summer than winter, so if it’s already 0 degree, the camera maybe can only cool to -20 degrees.

My camera struggles at 100% to hold -20 degrees in a refrigerator at a steady 5 degrees when it should be delivering closer to -30 at less than 100%

Power is NOT an issue.

As my friend is getting -35 easily on a 1600 at much less than 100% with ambient around 5-7 degrees you appear to saying that at 0 degrees ambient this camera can only do -20 (!!!)

Never heard that one before. My QSI is not affected so badly operating at 0 degrees and without an issues an enjoys the extra cold without an issue.

So the colder it get's the worse the TEC performs ?

Very strange and if I had known that instead of believing the advertised capabilities I would never have bought the camera.

You appear to be acknowledging that this cameras cooling capabilities are limited and much worse than your other cooled cameras.

In that case I will return the camera and request a REFUND. New South Wales consumer law is extremely strict on false advertising.

chad

Hi Ian，

Sorry for the problem.

We have done the same test in the past. Accroding to our test, in the refigerator, cooling it to the -30 degrees is avaliable.

Beyond our test, I noticed that it is also avaliable in summer for your camera. So I think the camera should be fine, the problem should be caused by other reason.

So can you test the following steps?

1, put the camera into the refigerator for 1 hours first.

2, Connect the camera and Cooling it.

3, Check the result.

Thanks

Chad

ilparr

Thanks for you thoughtful and appropriate response Chad

I will put the camera in for one hour first before connecting and send you the results and TemperHum logs next week.

Ian

ilparr

Hi Chad

I ran the test as requested including leaving the camera off in the fridge for one hour and then powered up and connected (No de-icing enabled)

As before it struggles to hold 20 C at 5 Degrees ambient and is basically running at 100%

Target Temp 25 is un-achievable which would be 30 below ambient

As before when I first used the camera outside at around 7 degrees ambient it really struggles and was not stable under normal conditions a problem I have never experienced with my QSI 690

The Camera was advertised as -35- to -40 capable (not -30 if everything works)

I would certainly not have bought if the best it could do was -30 and the actual performance is frankly a huge disappointment as it would seem ZWO failed badly in upgrading the TEC to deal with new chip or this one is a failure in manufacturing and quality control.

Up to this point I heard mostly good things both from other users for other models and you other models thrash this one on Temperature control.

Here are the results of my tests in a spread-sheet

https://drive.google.com/open?id=1fgNFnPdH6tx763VgEXZdyYUzcr6_dTm4

I have spent quite a bit of time on this problem so I am ready to hear what you now propose before I take further action.

Regards

Ian Parr

stefanob60

I think that ZWO is meeting problems to answer about limits/defects that seem to afflict this model.

About dew/frost frequent problems of just bought cameras the only answer is always to open it and to redry desiccant tablets. And the anti-dew heater is working? And the warranty, if I open with a no correct process and I'll damage it, I ask?

About cooler limits and the purely theoretical -35/-40, the answer is a refrigerator test.

I have sent my new 071 mc Pro to the assistance service and I hope that they quickly solve these problems for this fine expensive camera, although I fear that ZWO should recall/replace cameras with problems (how many?) for a decisive hardware upgrade.

chad

ilparr wrote:

Hi Chad

I ran the test as requested including leaving the camera off in the fridge for one hour and then powered up and connected (No de-icing enabled)

As before it struggles to hold 20 C at 5 Degrees ambient and is basically running at 100%

Target Temp 25 is un-achievable which would be 30 below ambient

As before when I first used the camera outside at around 7 degrees ambient it really struggles and was not stable under normal conditions a problem I have never experienced with my QSI 690

The Camera was advertised as -35- to -40 capable (not -30 if everything works)

I would certainly not have bought if the best it could do was -30 and the actual performance is frankly a huge disappointment as it would seem ZWO failed badly in upgrading the TEC to deal with new chip or this one is a failure in manufacturing and quality control.

Up to this point I heard mostly good things both from other users for other models and you other models thrash this one on Temperature control.

Here are the results of my tests in a spread-sheet

https://drive.google.com/open?id=1fgNFnPdH6tx763VgEXZdyYUzcr6_dTm4

I have spent quite a bit of time on this problem so I am ready to hear what you now propose before I take further action.

Regards

Ian Parr

Hi Ian，

Sorry for the late reply.

I have been busy this time and have not noticed the forum.

Got your testing, I will talked with our structural engineer to check out what happened.

Thanks

Chad

ilparr

Thank you

Figured you were busy

Ian

chad

Hi Ian，

Sorry for the problem.

I talked with my colleague. Usually, our temperature testing is under the room ambient. In this circumstance, the sensor's temperature and the ambient temperature are close. But if the ambient temperature is lower, the different between sensor and ambient will increase. the sensor will be warmer than the ambient. So in the lower temperature, the cooling efficiency will decrease.

And according to our test, when the ambient is -10degrees, there is still a 30 degree temperature difference between the sensor's starting temperature and the final temperature.

For your problem, did you remember the camera's starting temperature?

Thanks

Chad

ilparr

Hi Chad

Thanks for getting back to me.

Per your request I cooled the camera for one hour before connecting and the synchronized image and TemperHum readings were in the spreadsheet I sent you. Every reading was delivered from -19 to -23 running continuously at 100%.

I used both a 12V Li Battery (delivering a steady 13.6 Volts) and a 3 Amp AC 240-12 Volt 3 Amp Adapter.

I placed the camera on the top shelf and and the TemperHum on shelf below as the camera's TEC releases heats which you are stating would actually improve performance. Apart from occasional fridge raids the temperature on the second shelf remained stable.

If could run run the test again at room temperature (currently around 20 degrees) but this started after the camera temperature fluctuated wildly (+-5 degrees) when i first ran it outside at around 7-10 degrees ambient. So I purchased the TemperHum to make accurate readings.

In summer it would fail to reach zero while my QSI which advertised -45 and delivers -a STABLE < -10 degrees at over 30 degrees ambient while running at than around 85-90%%

The camera was and still is advertised as capable of -35 to 40 degrees below ambient which is clearly impossible and if only capable of of -30 I would never have bought it from Bintel.

See https://www.bintel.com.au/product/zwo-asi071mc-pro-cooled-astronomy-camera/?v=6cc98ba2045f

ASI071MC Pro has a two-stage TEC cooling system that allows deep cooling (35°C-40°C below ambient). You will need an external power supply to power the cooler. An AC-DC power adapter is not included in this package, however you can order one from here.

So the camera is being advertised with capabilities it is clearly incapable of delivering by your own admission.

I purchased the camera and off axis guider at the same time.

This clearly false advertising which strictly illegal in New South Wales and would prefer to get either a camera that performs as advertised or my money back and an apology for wasting my time.

I suggest you take this up with Bintel, whom I have dealt with for over 18 years, and get back to me with a practical solution before I have to take it further with NSW Consumer Affairs.

https://www.fairtrading.nsw.gov.au/help-centre/online-tools/make-a-complaint

It sounds like the camera is disappointment to say the least and a weak link in what was otherwise a highly regarded product line and this cannot be good for your reputation.

Ian

ilparr

Hey Chad

It's been over a month and no reply (???)

I have not used it since I did all the testing and sent you the detailed results of TemperHum testing in a controlled environment that confirmed I have a camera that struggles badly to hold -20c at 5c ambient and runs continuously at 100% doing so. I summer it here wouldn't get any-where near zero.

Is the TEC on the ASI701 under-engineered or simply faulty ?

Should I return the camera and ask for a refund or a replacement or credit against a model that can deliver as advertised?

Please respond

Thanks

Ian

katherine.tsai

Hi Ian,

Sorry about the delay. Chad has been busy with other things recently, he may have forgotten this problem. I confirmed this question with him.

We discussed the effect of temperature on TEC efficiency with TEC suppliers. Generally speaking, the lower the temperature, the lower the efficiency of TEC, so the temperature difference will be smaller, which is unavoidable.

And, usually we lower the temperature in order to get a smaller dark current, which in turn improves the signal-to-noise ratio of the image. For the 071Pro, after -10 degrees, the dark current is essentially unaffected by temperature, in which case the lower temperature does not improve the image quality. On the contrary, the life of the internal components of the camera will be shortened due to the low temperature, so we do not recommend you setting a lower target temperature.

ilparr

Hi Katherine

Thanks for getting back to me and I really appreciate you taking your time to respond.

Very interesting.

My tests were done under controlled conditions and fully logged (Temperature & Humidity) and it was claimed in an earlier post to this topic that ZWO tested the camera's TEC and it was capable of -30 below ambient.

by chad » Wed Jul 17, 2019 12 pm

... We have done the same test in the past. Accroding to our test, in the refigerator, cooling it to the -30 degrees is avaliable.

So now that no longer applies and I should be happy with -15C as getting colder does not return better dark current and

I risk damaging 'internal components' ? It was advertised as -capable of -35 to -40, not -30, or -20.

The camera has remained un-used since I ran the tests and I have gone back to using my QSI while this issue drags on.

I see no point in continuing to seek answers from ZWO as the answer keeps changing.

I have friends with other 'cheaper' models telling how good their TEC's perform, getting -30 or better @ 5c without risking damaging the TEC running continuously at 100%

As the camera is not 'faulty' and I would get the same results from any ASI701 MC Pro, I am ready to returned this camera to the supplier and ask for my money back. This has been a complete waste of a lot my time.

I will look elsewhere for a CMOS solution.

Thanks

Ian

katherine.tsai

Hi Ian,

Could you send the camera the back for further examination? We will try to find out the problem and fix it. You can contact support@zwoptical.com about the repair.

ilparr

Thank you Katherine

katherine.tsai

My pleasure.:)