27 replies to this topic

[DonBoy]

As a fun project I put together a simple Peltier cooler module for my ASI290mm and one for my ASI224mc.  I get a 15C reduction in temperature drop when running with the cooler.  Here are some pictures of the cooler attached to the camera and a screen shot of the preview screen of the ASI290 on SharpCap with and without cooling.

 

 

Edited by DonBoy, 15 July 2017 - 03:11 PM.

[DonBoy]

I've increased contrast to the level where the cooled image is just showing noise so one can easily see the difference without cooling.

 

No cooler

 

Cooler on

Edited by DonBoy, 15 July 2017 - 03:13 PM.

[DonBoy]

Here is the ASI224 cooled with temperature regulator.

 

 

Attached Thumbnails

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[larryjh]

Don, where/what parts did you get for this project?  Looks like a nice DIY alternative to getting the cooled model, if the price of the parts is reasonable.  Also, how's the weight of your cooler?  I might want to try this on my ASI 224MC.  Thanks!

[DonBoy]

Larry,

 

I bought everything on Amazon.

 

Message me here for a list of parts.

[Astrojedi]

Nicely done Don. Very creative. How much did the parts cost? 

[DonBoy]

Nicely done Don. Very creative. How much did the parts cost? 

Thanks Hiten.  Some parts are sold in pairs, but it brakes down to just under $25 to build one unit, power supply not included.  

[Astrojedi]

I've increased contrast to the level where the cooled image is just showing noise so one can easily see the difference without cooling.

 

No cooler

Screen Shot 2017-07-15 at 3.09.48 PM.jpg

 

Cooler on

Screen Shot 2017-07-15 at 3.01.40 PM.jpg

Don,

Are both these screenshots at the same bit depth?

 

I ask as I have not noticed such a drastic difference with cooling on (also cooling does not impact the frame in this way). If the first one is at 8bit it could explain why the background is brighter. Otherwise I would check for light leaks.

 

Also using such long exposures at such high gain levels will likely lead to clipping and quantization loss. I would use 15-30s or less as they would be better indicators of performance in actual use.

 

Hiten

[Astrojedi]

 

Nicely done Don. Very creative. How much did the parts cost? 

Thanks Hiten.  Some parts are sold in pairs, but it brakes down to just under $25 to build one unit, power supply not included.  

 

Excellent... cool diy project for those interested. How much did the power supply cost?

[DonBoy]

P. S. are $11.   But I already had several of them.  The rating for my setup requires a 12VDC rated for 4A,  but cooler runs at 2.5A.

[DonBoy]

 

I've increased contrast to the level where the cooled image is just showing noise so one can easily see the difference without cooling.

 

No cooler

Screen Shot 2017-07-15 at 3.09.48 PM.jpg

 

Cooler on

Screen Shot 2017-07-15 at 3.01.40 PM.jpg

Don,

Are both these screenshots at the same bit depth?

 

I ask as I have not noticed such a drastic difference with cooling on (also cooling does not impact the frame in this way). If the first one is at 8bit it could explain why the background is brighter. Otherwise I would check for light leaks.

 

Also using such long exposures at such high gain levels will likely lead to clipping and quantization loss. I would use 15-30s or less as they would be better indicators of performance in actual use.

 

Hiten

 

They were both shot one right after the other with Mono 16 bin 1.  I just raised the display contrast to the same level to show how much difference there is.   Here are two shots of the same but with the display contrast at 1.0.

 

Cooler on

 

No Cooling

[Alfred Tan]

Thanks Dan for sharing your knowledge with us.

 

Alfred 

[Astrojedi]

Don,

Looks good. Did you find a significant difference for shorter exposures as well say 8-10s?

 

Honestly I have rarely ever used sub exposures longer than 10s even for H Alpha viewing. I cannot imagine a scenario for EAA where you would need 60s exposures with this camera.

 

You should also write a how-to article / post for folks who are interested in doing this.

 

Hiten

Edited by Astrojedi, 19 July 2017 - 08:58 AM.

[Alien Observatory]

 

Hmmm a few left over parts from a Mallincam experiment...might just fit on the ZWO290mm....

 

TY Don for the post...Pat Utah

Edited by Alien Observatory, 19 July 2017 - 09:26 PM.

[Stargazer3236]

IMG_0410.jpg

 

Hmmm a few left over parts from a Mallincam experiment...might just fit on the ZWO290mm....

 

TY Don for the post...Pat Utah

Pat, where did you get that kit in your picture?

[Alien Observatory]

David, Sorry for the delayed response,  Each Item was bought separately.  The 70 x 70 MM Fan Assembly is way to big for the ZWO 290.  Pat Utah

 

TEC Device ... https://www.amazon.c...t/dp/B002UQQ3Q2

 

70 x 70 Heat Sink / Fan ... https://www.newegg.c...Id=1&Submit=ENE

 

Controller ... http://www.ebay.com/...be/181208692623

Edited by Alien Observatory, 24 July 2017 - 12:25 PM.

[The Enginear]

Don, I just wanted to thank you again for the parts list and for answering my questions. I just finished adding a DIY cooler to my new ASI294MC, and I think it turned out great. I haven’t tested it fully yet, but in my initial test it dropped ten degrees Celsius and was still dropping when I shut it down to finalize the wiring and take some pictures of it, which I’ll post once I can resize them.  

 

I hope to try it out tonight before the moon comes up.

 

I basically copied what you did, except I think I mounted the controller a bit different - one half of the case from an old SD card, some electrical tape and some high temp open-cell foam made a nice backplate and stand-off for it - and coincidentally, the mounting holes for the controller lined up nicely with the wider fins on the heatsink. I used two of the original fan screws to mount the controller to one side of the heatsink.

 

I’ll mainly be using it with a XT8g Newtonian, but I may try experimenting with my 102 SLT achromatic too.

 

With your info and help it was an easy build, and it seems to work quite well - thanks again! 

 

 

[glend]

Longer term this cooling system may give you problems. The non-cooled ASI cameras do not incorporate dessicant moisture control in the sensor chamber. Condensation is likely in cooling and warming cycles. This is a common problem found in DSLR cooling hacks, which can lead to internal failure.  You could try using Argon purging of the sensor area but I doubt the sealing is good enough and you would have to work out a way to inject the gas. 

I have built several cold finger cooled Canon's, and the only way I found to beat condensation was to enclose the camera in an Argon filled plastic zip lock bag, but this requires a good seal around the tube extension, and a screw in filter to seal the chamber in the front. Good luck.

Edited by glend, 26 September 2018 - 01:54 AM.

[The Enginear]

Longer term this cooling system may give you problems. The non-cooled ASI cameras do not incorporate dessicant moisture control in the sensor chamber. Condensation is likely in cooling and warming cycles. This is a common problem found in DSLR cooling hacks, which can lead to internal failure.  You could try using Argon purging of the sensor area but I doubt the sealing is good enough and you would have to work out a way to inject the gas. 

I have built several cold finger cooled Canon's, and the only way I found to beat condensation was to enclose the camera in an Argon filled plastic zip lock bag, but this requires a good seal around the tube extension, and a screw in filter to seal the chamber in the front. Good luck.

 

 

I'll be watching for that, but considering I live in an area where the relative humidity typically runs about 15-17%, I'm thinking that it's probably not going to be a significant issue for me. I ran it for a few hours last night, and there was zero signs of condensation. 

[DonBoy]

Phil, glad I was able to help.  

 

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Having used the cooler for over the last 14 months in warm weather I have never experienced moisture on the sensor.  I can't recall using either camera when the sensor temperature went below 0C so can't comment on whether ice will form on sensor or window.  The camera housing will sweat alot so be aware of that.

[The Enginear]

As promised, here's a couple of pictures:

 

 

 

 

 

 

[DonBoy]

Very nice and neat.   Good job.

[The Enginear]

Phil, glad I was able to help.  

 

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Having used the cooler for over the last 14 months in warm weather I have never experienced moisture on the sensor.  I can't recall using either camera when the sensor temperature went below 0C so can't comment on whether ice will form on sensor or window.  The camera housing will sweat alot so be aware of that.

 

Thanks for the info on the moisture Don. I didn't even experience any significant condensation on the exterior case of the camera - that might change as the weather cools, but it was in the mid 80s when I started setting up early yesterday evening, and I stopped an hour or so after the moon came up, and it was still rather warm out. Like I said, the low humidity here will probably help keep condensation levels pretty low. 

 

I was able to get the camera body to cool from the ambient temperature (around 84 degrees Fahrenheit / 28.88 Celsius) to about 59 degrees F / 15 C in a relatively short period of time - a drop of about 25 degrees (Fahrenheit), which is quite an improvement IMO.  Of course, when the ambient temperatures outside are lower, I can always adjust the thermostat on the controller as needed to avoid icing and condensation, or just shut it off. I put an inline switch on the 12V power cable for just that purpose. You can just barely see it in the picture with the XT8g on the far right side of the photo. 

Edited by The Enginear, 26 September 2018 - 01:28 PM.

[The Enginear]

Very nice and neat.   Good job.

 

Thanks!

[DonBoy]

Phil,  what's more impressive is if you record the sensor temperature without cooling vs. final cooling level and you'll see even a greater differential than comparing to ambient temperature.

 

Your dryer climate probably helps in keeping the camera from sweating.

Edited by DonBoy, 26 September 2018 - 01:33 PM.