Smartphone coolers for AP

[Dark Raven]

Before we start, yes, I am aware this is astronomy and not a smartphone accessories forum.

Then why a smartphone accessory review?
Well, I had a brain-fart, bear with me.

Why a review and not DIY forum?
Because I used off the shelf products without any modification and tested them.

Why such poor testing methodology?
Proof of concept, also brain-fart remember?

So, what is this all about then?
What if we repurpose a smartphone cooler for planetary or DSLR/Mirrorless camera? Interested in detail? Then read on…

 

TL / DR
Repurposing smartphone coolers for planetary or DSLR/Mirrorless cameras delivers approx. -10°C compared to ambient temperature in reversible and non-destructive manner. At least in my tests.

Introduction and how did this come about?

For quite some time I wanted to cool my Canon DSLR camera especially in the summer and all I found were quite destructive, irreversible and/or inconvenient bulky solutions I really didn’t like. Some found on this forum or in this video.
I wanted something bit more elegant and something that will allow camera’s regular daytime non-astronomy use. Then, some tima ago I saw announcement for Canon EOS R5 C with built in cooler,

 

and asked myself is there something for retrofitting regular DSLR / Mirrorless camera? After some searching, I found Tilta’s Canon EOS R5, R6 cooling fan.

 

Peltier cooling, external power plug so it doesn’t drain camera battery, dual fan speed with on/off switch. Thought it was pretty cool, especially as I am contemplating purchase of Canon R6 in near future. But for now, I wanted to get something that could be a bit more universal and versatile. Possibly used on planetary camera as well.

What I found were smartphone coolers. Out of all that are mobile gamer oriented and full RGB LED lighted I found two that were astronomy friendly. Black Shark Magnetic Cooler and Black Shark Phone Cooler. Best thing of all were the prices. Although they wildly vary from one online retailer to another. 

That was too good not to get them both and few days later the boxes were on my desk ready for testing.

 

Magnetic cooler is interesting as it sticks to all MagSafe compatible products and any ferro-metallic surface.

For the rest there is a magnetic sticker.

Gaming Cooler uses clamps to hold itself to the camera.

 

Dimensions

Dimensions were one of the key features in choosing these two coolers as they would have to fit on top of planetary camera and in the DSLR/Mirrorless flip screen recess.

ZWO ASI planetary camera with diameter of 62 mm

 

Black Shark Magnetic Cooler Dimensions

The magnetic sticker that comes with this cooler is used to enable connection on magnetically inert surfaces. This will come in handy on planetary cameras as they are usually aluminium based. While I am in the market for new camera, I chose not to use it on the ASI120MM-S guider, but rather test the cooler simply placed on top without the sticker. One should be mindful where and how this sticker is applied as only one is supplied.

Cut-outs seem to fit perfectly except for the middle screw hole.

 

Magnetic sticker will be useful on DSLRs as they often have Magnesium alloy, Aluminium alloy, and polycarbonate resin with glass fibre, or some such combination bodies. The size of magnetic sticker is just over half a mm, and it will have minor impact on closing the lid on DSLRs as will be seen later.

 

Black Shark Phone Cooler Dimensions

Clamps are 60 mm apart which makes it hold the Ø 62 mm ASI120MM-s and they stretch to max 80 mm.

 

Bench test

I tested both coolers on my ASI120MM-S guide camera, indoors at ambient temperature of 25°C.

 

   

I opted for internal temperature sensor of the camera rather than measuring outside temp of the housing because that is what is recorded in all our FITS files during imaging sessions. For measuring I used ASIStudio ASICap. Not perfect but sufficient for proof of concept.

First thing I did is recorded the temperature of the connected camera without the cooling. While taking subs I recorded temp of 26.7°C and while idling it was 26.0 °C.

 

Capture data:

[ZWO ASI120MM-S]
Auto Exp Max Exp = 30000ms
Auto Exp Max Gain = 50
Auto Exp Target Brightness = 100
Bin = 1
Brightness = 0
Capture Area Size = 1280 * 960
Colour Format = RAW16
Debayer Type = GRBG
Exposure = 8.30989s
Flip = None
Gain = 50
Hardware Bin = OFF
High Speed Mode = OFF
OverClock = 0%
StartX = 0
StartY = 0
Temperature = 26.7 C
Timestamp Frames = OFF
USB Limit = 86
USB Port = 2.0

Resulting uncooled .fits file looks like this:

 

Now it was time turn on the cooling with Black Shark Magnetic Cooler. Gradual temperature decrease can be seen below. Not surprising, we can observe that each subsequent degree of temperature reduction takes a bit longer.

Finally, we achieve minimum temperature of 17 °C.

Capture data:

[ZWO ASI120MM-S]
Auto Exp Max Exp = 30000ms
Auto Exp Max Gain = 50
Auto Exp Target Brightness = 100
Bin = 1
Brightness = 0
Capture Area Size = 1280 * 960
Colour Format = RAW16
Debayer Type = GRBG
Exposure = 30s
Flip = None
Gain = 50
Hardware Bin = OFF
High Speed Mode = OFF
OverClock = 0%
StartX = 0
StartY = 0
Temperature = 17.0 C
Timestamp Frames = OFF
USB Limit = 86
USB Port = 2.0

Resulting cooled .fits file looks like this:

 

After turning the Magnetic Cooler off and letting the camera warm back to ambient temperature, it was turn for Black Shark Phone Cooler.

Finally, we achieve stable minimum temperature of 17.7 °C with drops down to 17.0 °C.

Capture data:

[ZWO ASI120MM-S]
Auto Exp Max Exp = 30000ms
Auto Exp Max Gain = 50
Auto Exp Target Brightness = 100
Bin = 1
Brightness = 0
Capture Area Size = 1280 * 960
Colour Format = RAW16
Debayer Type = GRBG
Exposure = 8.30989s
Flip = None
Gain = 50
Hardware Bin = OFF
High Speed Mode = OFF
OverClock = 0%
StartX = 0
StartY = 0
Temperature = 17.7 C
Timestamp Frames = OFF
USB Limit = 86
USB Port = 2.0

Resulting cooled .fits file looks like this:

 

Consumption.

For Black Shark Magnetic Cooler we have: 4.54 V and 1.27 A, giving us just a bit shy of 5.8 W.

For Black Shark Phone Cooler we have: 4.69 V and 0.74 A, giving us just a bit shy of 3.5 W.

With 40% lower energy consumption and half of the price for only 0.7 °C difference it appears that Black Shark Phone Cooler performs better. Given the small cost, especially compared to the rest of astronomy gear and manner in which you power that gear (battery or grid) this should not be a big impact. One thing I was not able to test is the impact of fan vibrations on the camera stability during sub-exposures. For this I would need to do a field test.

Given the above proof of concept test and that others have successfully tested concepts of Peltier cooling on DSLRs, side position of the charging port, non-removable cooler clamps combined with the lip on the bottom of my Canon DSLR I decided to postpone temperature test until I get new DSLR / Mirrorless camera.

Slim L shaped USB-C cable was also protruding a bit out of the flip screen recess.

 

What I did do, is tested the concept on few other cameras in local electronics store. Given it was general electronics store they had only few entry level cameras on display. Nevertheless, they served the purpose to give general idea and understanding.

Canon 90D like my DSLR has a flip screen recess bottom lip, which makes it unsuitable for non-destructive application of considered coolers.

 

Canon 850D does not have a flip screen recess bottom lip, which makes it suitable.

 

Canon EOS 250D fits the cooler with a bit of overhang but it should not be of consequence.

 

Sony A7 II is not suitable due to its screen not clearing the back of the camera.

 

Nikon Z50 barely fits.

 

Nikon D5600 works fine.

 

Another thing to consider regarding the magnetic sticker on all DSLRs / Mirrorless cameras is that it somewhat hinders proper closing of the flip out screen. Not by much, but still to be aware of.

 

Closing

DSLRs and these smartphone coolers will never be able to produce results anywhere near dedicated AP cooled cameras will. However, with the introduction of backlit planetary cameras like ZWO ASI585MC and Player One Uranus-C  based on IMX585, new possibilities are coming to amateur entry AP. Just look at what Luke Newbould managed to capture in his YT video: Mono VS OSC? 

Now suppose adding cooling of -10°C below the ambient temperature. I imagine it could only get better.

This review was not detailed or scientific. Intention was to test the concept of repurposing smartphone coolers to AP and share the idea with community. I hope it will help during the upcoming summer.

CS,

Dark Raven

Edited July 8, 2022 by Dark Raven

[Ratlet]

I think with something like the player one Saturn, this could be very useful as the sensor doesn't have a lot of thermal noise at ambient-ish temperatures.  Could be very interesting and is something I'm wanting to try if I stick it out with astrophotography

[Elp]

Interesting test. Wonder if you could apply thermal paste either metal on metal contact or via thermal pads, arctic silver compound works wonders with CPU cooling.

 

[Dark Raven]

8 minutes ago, Elp said:

Interesting test. Wonder if you could apply thermal paste either metal on metal contact or via thermal pads, arctic silver compound works wonders with CPU cooling.

I ordered the Icy Box M.2, 3.2 W/mK Thermal Pads but shipment got delayed, and looks like it will not make it before I leave on vacation. If I manage to get them or any other while there, I'll update the review.

[happy-kat]

Interesting idea and great write up. I see that you mean about colourful LEDs. I wonder what they use for the semiconductor material.

[bomberbaz]

15 hours ago, Elp said:

Interesting test. Wonder if you could apply thermal paste either metal on metal contact or via thermal pads, arctic silver compound works wonders with CPU cooling.

 

If you have a very flush fitting, cooler on camera back is it really necessary. 

What level of difference might you expect?

[Elp]

42 minutes ago, bomberbaz said:

If you have a very flush fitting, cooler on camera back is it really necessary. 

What level of difference might you expect?

On a CPU I've had 10-20 degrees immediate difference switching to a quality compound, the amount applied makes a great difference too, if you apply too much for example it's counter productive. 224 cooling will vary of course, I doubt for example the back of the camera sensor is mounted flush to the back face of the camera unlike a CPU heatsink.

Fans make a huge difference to computer cooling. Switching default case fans from 60-80mm to 100-120mm ones running slower drops temperatures due to the CFM change.

 

Edited July 9, 2022 by Elp

[bomberbaz]

3 hours ago, Elp said:

On a CPU I've had 10-20 degrees immediate difference switching to a quality compound, the amount applied makes a great difference too, if you apply too much for example it's counter productive. 224 cooling will vary of course, I doubt for example the back of the camera sensor is mounted flush to the back face of the camera unlike a CPU heatsink.

Fans make a huge difference to computer cooling. Switching default case fans from 60-80mm to 100-120mm ones running slower drops temperatures due to the CFM change.

 

I made a homemade cooler before using a peltier chip and pc cooling fan, however I first tried cooling with just a fan.

The cooling fan alone dropped temperature of the camera about 2.5C only. When I added the peltier chip the cooling increased to around 15C but the big issue was power consumption. The peltier chip, which was the lowest 12V I could find was incredibly hungry. In the end I scrapped it due to the whole setup being unwieldy as well as power hungry.

So I am very keen to try out this phone cooler, a reduction of circa 10 degrees gives you a very workable camera temperature as long as ambient is within reasonable parameters. What that is only time will tell but I am guessing 20C ambient will give you a decent camera temp to start from. Obvs the lower the better (within reason).

[Elp]

It'll be interesting to see your results. At that temperature you also don't need to worry about any condensation issue.

[happy-kat]

I'm interested in what has been used for the TEC semiconductor. Watching YT one even had a ios app mentioned where you could change the LED colours!!

[Dark Raven]

I had the chance to grab some subs last night and did a small field test with the cooler on the back of ASI120MM-S. I was quite tired at 4 AM and did not have patience to wait beyond 15 min. 

 

 

Initial camera temp was 16.7 °C and achieved temp was 9.5 °C giving ΔT of 7.2 °C. Please note and ignore the focus as the guide camera is deliberately defocused.

I will assume there are two reasons for lower ΔT than achieved in the initial bench test above.

1. Limited timeframe of only 15 min.
2. The cooler was hung from below (on bench test it was sitting on top), thus having lesser adhesion to the back of the camera.

Therefore I would fully support addition of thermal pads that should improve adhesion and heat transfer.
I will test Phone Cooler further as I acquire the pads or paste and Magnetic Cooler when I get new camera (might take some time).

 

 

[bomberbaz]

29 minutes ago, Dark Raven said:

I had the chance to grab some subs last night and did a small field test with the cooler on the back of ASI120MM-S. I was quite tired at 4 AM and did not have patience to wait beyond 15 min. 

 

 

Initial camera temp was 16.7 °C and achieved temp was 9.5 °C giving ΔT of 7.2 °C. Please note and ignore the focus as the guide camera is deliberately defocused.

 

I will assume there are two reasons for lower ΔT than achieved in the initial bench test above.

1. Limited timeframe of only 15 min.
2. The cooler was hung from below (on bench test it was sitting on top), thus having lesser adhesion to the back of the camera.

Therefore I would fully support addition of thermal pads that should improve adhesion and heat transfer.
I will test Phone Cooler further as I acquire the pads or paste and Magnetic Cooler when I get new camera (might take some time).

 

 

I will hopefully be doing a magnetic cooler test later tonight. Everything is setup and just awaiting darkness to come along.  I only plan doing 2x 20 minutes though using 224mc OSC. That is 20 without cooler and 20 with. 

My bench test results copied yours exactly.

[Dark Raven]

Looking forward to your test results.

3 minutes ago, bomberbaz said:

My bench test results copied yours exactly.

👍

[bomberbaz]

41 minutes ago, Dark Raven said:

Looking forward to your test results.

👍

unforcast cloud has rolled in, 😱

Tomorrow nights forcast is better so here's hoping

[happy-kat]

Looks promising as no obvious star shape issues from the cooler.

[Dark Raven]

 

@bomberbaz Thank you for posting your findings. 👍

 

[Dark Raven]

New camera is ready and waiting. 😀

I managed to gather the baseline without cooling, but the weather is not cooperating... 😕

 

 

[bomberbaz]

On 24/09/2022 at 16:28, Dark Raven said:

New camera is ready and waiting. 😀

I managed to gather the baseline without cooling, but the weather is not cooperating... 😕

 

 

any results to report on yet

[Dark Raven]

Sadly, no... 

[powerlord]

as it's just a peltier and fan, it'd be interesting to whip that usb plug off it, and attach it to 12v. obviously fan might blow up, but of not, you may be a heck of a lot more cooling.

[Dark Raven]

Thought about it but the fan is DC 5.0 V...

After seeing this FLIR video I thought it might be enough with backlit sensor.

I had this below in mind as starting DIY idea, but than stumbled upon smartphone coolers and it took life of it's own.  
Might still revert to it though... This TEC1-12706 Modul 36 W, 12 V might be ideal for ASIAIR+ port limit of 3A.

Edited September 29, 2022 by Dark Raven

[powerlord]

yeh but it's just a motor. itll run fine at 12v. it will run fast.. and maybe too fast and get hot or vibrate, but I doubt it - they are pretty well balanced these days, and brushless. you can always still a wee resistor in series with fan to slow it down.

[Dark Raven]

Yup, that should be an easy fix to do. However, I chose to go with 5.8 W and not with full 36 W due to condensation concerns. Stock cooled cameras have built in condensation management, through built-in desiccant tablets

and / or desiccant tubes,

planetary cameras do not.

It would be a shame to end the night early due to fogged up sensor in best and fried board in worse case. With new backlit sensors mild cooling should be sufficient to produce good results.
Cant wait enough to clear up and finally go out imaging and testing. 
 

[vernmid]

This looks very interesting.

I am hoping to try and replicate your findings with a slightly different cooler setup and will happily share my results here.

I'd never heard of smartphone coolers until reading this thread ☺️

[Dark Raven]

Finally, I had some chance to test. 
Starting temperature was 15.1 °C

 

Magnetic cooler managed to get it down to 6.3 °C just before I started taking calibration frames.

It managed to achieve ΔT just a bit shy of 9 °C 

Important to note is the level of condensation visible on the images below. ZWO ASI585MC with magnetic cooler and ZWO ASI120MM without any cooling on the same rig at the same time.

 

 

After I manage to process images, I hope I will be able to give final comparison and conclusion.

Edited October 30, 2022 by Dark Raven