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Chiller box for DSLR camera body


fwm891

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I have attached a few images of a home made chiller box I use with my Canon 450D DSLR body.

Essentially its the same as the Gary Honis V 3 unit with a couple of changes to suit me...

Its constructed from aluminium sheet and uses a Peltier heat exchanger as the cooling device. There's a large heatsink and fan unit on the exterior to remove unwanted heat from the peltier, and a smaller heatsink and fan inside to circulate the chilled air. The box is sealed as well as possible to retain the cold air and insulated with polystyrene sheet.

I pre-cool my camera and MPCC flattener in a fridge (in a sealed bag) for a couple of hours as it takes time to get the camera body cold right through and use the chiller to maintain the cooling. It attains about 15º C below ambient. I keep a piece of kitchen toweling inside to soak up the small amount of condensation produced. Fans turn on when power is attached and the Peltier is activated by a separate switch in the 12 VDC supply line. At the end of a session the unit is left closed with just the fans running for a hour or two to prevent condensation forming as the unit slowly warms up.

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Looks an interesting piece of kit. Do you have any 'before and after' astro images to show the benefits of cooling. Is there much noise reduction?

I'm guessing you need to be tethered to a computer for this since the camera can't be accessed in any way (e.g. for focusing) once cold?

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I'll try and get before & after shots - bit awkward though as the camera takes quite sometime to cool down. What I may do is shoot with a second body but it won't be the same model so results won't be exact comparison. Or I could shoot on different nights then conditions change etc, etc...

Regarding noise levels its great I've done a number of tests at different iso rating with the camera body capped in the chiller and taken exposures during cool-down from ambient. Initially noise shows as bright RGB + hot pixels on a black background. Although the noise pattern remains during the cool-down the intensity of the RGB pattern drops leaving only the hot pixels at full intensity. Dropping the ISO rating also helps as would be expected. I've attached a set from an ISO 800 test, each image is a 100% screen grab from the same area of each frame. The control is taken at ambient with the timings of each 10 min sub shown. Cool-down from ambient with the chiller alone is quite lengthy hence the reason I pre cool the camera in a fridge so the chiller just maintains or slightly reduces the fridge cooling.

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Very interesting fwm891, we are just competing ours, a mix of the Honis & Swash Astro pages, a ready made box seemed easier to me.

I like your cut out for dropping the camera in, may add that to ours. We did try with ebay parts but found parts from a secondhand camping cooler easier to bolt together, yet to mount on the scopes and weight is a worry, with the camera we are up to 2kg. We get much the same drop in temp.

JCJC's dad

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Well done.

Very interested in this as I just ordered a peltier coolbox from Germany as my electronic skills are zero.

https://www.teleskop-express.de/shop/product_info.php?products_id=4824#ebericht

How much does your one weigh without the camera? Do you suffer from any flexure?

Also interested about leaving the fan on to avoid condensation, not sure if I will be able to do that with mine. Maybe I need to leave it in a plastic bag inside the box, and is that a good idea or not?

Carole

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Great idea - Carole, I look forward to your thoughts on the cooling box - I didn't know you could buy them ready made. Like you my electronic skills are zero. Mmm, what a good idea for the future me thinks!

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Carole / Swag72,

Mine weighs 980 gms or 2 lbs 2.5 oz + the camera body.

Good idea about leaving the camera in a sealed bag, it may restrict the cooling slightly but make sure you put a small bag of silica gel or similar in with the camera to absorb any moisture as it will be trapped there. Also my UHC-S filter effectively seals the front of the camera so if you don't use filters you amy have to consider moisture getting directly onto the chip!

Not had any problems with flexure at the focuser when in use. - Francis

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Update: Hope you don't mind fwm891 as it's all to do with the same thing.

The German Peltier cooler has arrived (very fast service 2 days from ordering). Fitted it all up, seems to work OK but the hole at the front is not big enough to accommodate my Flattener and I can't change the battery without dismantling the whole thing.

So I think I am going to have to enlarge the hole at the front and get an electric "battery". :)

Otherwise I think it will work well and they recommend putting in a bag of silica gel if there is humidity.

Carole

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We had problems with the flattener thumb screw being a bit large, replaced it with a grub screw (we are popping the camera in the box and fitting the flattener from outside, was catching the insulation).

JCJC's dad

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Hello Carole, looks like an interesting bit of kit, can you post some pictures?

When you say the hole at the front is too small, dies it not allow the camera t mount through the aperture ?

Does the camera fix directly to the box ? is there a socket to allow cables to pass though fro the camer to say your PC ?. sorry about all the questions

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is there a socket to allow cables to pass though fro the camer to say your PC ?. sorry about all the questions

I was wondering that too... It doesn't look like it on the pictures but it wouldn't make sense if there was no cable "hole".

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Re: Hole for cables - yes there is an aperture about 25 mm (H) x 8 mm (W) in the opposite end to the heatsinks, (the hole is plugged with a piece of foam rubber to form a seal) this allows access for the usb and power cable to the camera. My original box although I made it with an aperture large enough to take the 'T-mount' adapter also gave me problems locking the flattener in place, thats why I modified the front panel to allow me to put the camera in as a complete unit. The modification also gives me a better seal around the flattener. In use I put a ring of foam rubber between the chiller box and the focuser to stop condensation forming on the flattener where it enters the focuser as the 'cold' is conducted well into the focuser which gets surprisingly cold after a long session (4 hours my longest run so far).

Carole - hope your mods go okay. Francis

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Tip: I used the heatsinks and peltier unit from a Halfords beer cooler (12 litre size) although from what I could see of the coolers they are all powered by the same units. I used a couple of fans from Maplins as replacements (now I have a useless drinks cooler to keep all my odd cables in!

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Tip: I used the heatsinks and peltier unit from a Halfords beer cooler (12 litre size) although from what I could see of the coolers they are all powered by the same units. I used a couple of fans from Maplins as replacements (now I have a useless drinks cooler to keep all my odd cables in!

We use Peltier cooling on our diode lasers at work- might see if I can find an old prototype or something lying around.

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Hi every-one, I don't think it's fair to highjack this thread with my own Peltier gadget as Francis started this to talk about his own project, so I'll start a new one called, Carole's DSLR cooler and answer your questions there.

Carole

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Carole - I don't have a problem with combining threads as they are virtually the same...

I'm trying to image the Cocoon neb with mine at the moment - body temp down to 2º C.

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Pardon my ignorance, but what are the advantages of doing this?

I used to freeze my 35mm film to hyper-sensitize it to allow faster film speed for shooting at night but am not familiar with utilising a similar concept with DSLRs.

I only have my old Nikon 35mm gear or a Panasonic compact digital (FZ50 not so compact), so I guess if I advance to astrophotography it will be my Nikon.

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Leo,

Cooling the camera reduces the thermal noise inherent in CCD and CMOS camera detectors. Dedicated CCD cameras for astro work will go way below the levels attained with the chiller but it does do a great job with DSLR cameras.

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Carole - I don't have a problem with combining threads as they are virtually the same...

Hi Francis, Thanks, well already started the new thread, but it looks to me above that the guys asked me a question and you answered it, so I thought it would be less confusing if questions addressed to me were in a separate thread.

My thread:

http://stargazerslounge.com/equipment-discussion/147357-caroles-dslr-cooler.html

I must say I am full of admiration for you being able to construct this yourself as you have saved yourself a heap of money and designed it to your own specifiations, whilst I am having to pay out for extra stuff to fit as well as buy the Peltier cooler in the first instance.

Carole

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Pardon my ignorance, but what are the advantages of doing this?

I used to freeze my 35mm film to hyper-sensitize it to allow faster film speed for shooting at night but am not familiar with utilising a similar concept with DSLRs.

I only have my old Nikon 35mm gear or a Panasonic compact digital (FZ50 not so compact), so I guess if I advance to astrophotography it will be my Nikon.

Cold cameras- there's a blast from the past. If I remember correctly a single frame of 35mm film was placed in the 'cold camera'. The back was packed with dry ice and the film was protected from condensation with thick transparent perspex plug.

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  • 7 months later...

How much current does your take Francis? I'm looking into what size Peltier I should get. The space taken by the camera isn't all that much so I would think a fairly low rated Peltier unit would suffice. Need to look into heat sinks and fans too. I have a couple of ancient duff laptops I can dismantle.

With so many cloudy nights (and days) it's a good time for making stuff :D

So far "on my books" are :-

  • Cooled DSLR (newest)
  • Filter Wheel
  • Focussing remote control (needs improving)

Also, electronics but not astronomical : -

  • Remote controlled multi-camera CCTV system
  • Webcams viewing SW (obsy) and North
  • Weather Stations

That's on top of household and smallholding jobs and repairs :clouds1: Yes, I like to keep busy! :cussing:

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