Cooler boxes for DSLR's

[hotspur]

Purchased a Mod'ed 40D for astro use,and looking at trying to get into getting a large amount of data,my observatory is all set up,but never really had dedicated camera for it.

I have seen astronomers here making little cooler boxes for their DSLR's so looking for some designs and how too's

I have heard of cold finger cooling,of DSLR's-but that's way beyond me! and far too scary to even think about!

Amazingly,a member here has done it.

http://www.iceinspace.com.au/forum/shop?t=50788wthread.ph

This chap who did this,is totally a god:bowdown:-well done Martin,disappointing to see so little feed back on his thread,as its one of the best I have seen here.

[wasyoungonce]

Chris.

I made cooler box (a Gary Honis knock-off (http://dslrmodifications.com/rebelmod450d16c.html)) capable of running my DSLR at or below zero. I noticed that when ~8C the sensor thermal noise was pretty low so anything below 8C is a good result.

I managed all this by using old computer HSFs, milling some material off the inner HSF so its base protruded out of the side of the box. (https://picasaweb.google.com/brokenback09/DSLRPeltierCameraCoolBox#) This directed the cold to the inner of the box. The result was quite successful.

But....you loose a lot of thermal efficiency attaching the nose piece to the focuser so this needs good insulating as well, which elongates cool down times. I used a cheap ebay temp controller. (http://www.google.com.au/imgres?imgurl=http%3A%2F%2Fwww.ther momart.com%2Fimage%2Fcache%2Fdata%2 FTemperature%252520Controller%2Ftem p%252520controller%252520BBQ-500x500.jpg&imgrefurl=http%3A%2F%2Fwww.thermoma rt.com%2Fthermostat-thermometer-temp-control&h=500&w=500&tbnid=UZFoG2TyvcPhuM%3A&zoom=1&docid=Zv0CIxTJXmIvdM&ei=EmLwU76_K87t8AWtkYHoAg&tbm=isch&ved=0CDcQMygvMC84ZA&iact=rc&uact=3&dur=878&page=5&start=140&ndsp=36) Yes it's not PWM thermal control, just on/off thermostat but... meh it works. Just note some of these controllers are 240V but you can get 12V versions.

DSLR mods yahoo group (https://groups.yahoo.com/neo/groups/DSLRmodifications/conversations/messages)is another good resource.
:thumbsup:

edit:
Oh IMHO...run your cooling Peltier system from a separate 12V source than the rest of the scope stuff.

[hotspur]

Thank you Brendan:thumbsup:

For those links,and advice-they look quite a good job.

I'll following up on these,and have a play around with the camera (a Canon 40D) as is,for a while,then try one of the mods in your links.

I am then thinking I might look at doing a cold finger cooling mod,I notice @Mill has done a great job,and there is a bit of info in his 2009 link.These cameras a basically worthless now,so might give it ago.

[wasyoungonce]

Cold finger is a much better idea wrt a cooling box in that cooling is applied to the sensor directly thus you don't need large wattage TEC.

However, you may need dew heater around the sensor glass and certainly pot the PCB areas to keep moisture out.

edit: link to martins build is dead!

[hotspur]

Yeah-if you google 'cold finger 40D mod' it will come up no problems,but the in house link does not work.

I will have a play with the cam as it is,after I get it from Bo,and then look at doing the mods in your thread (looks no scary,compared to the cold finger mod).But if I can get enough details on how to do @Mills job,I'll look at doing it.His results were amazing.

Wonder if others here have cold finger mod DSLR's

[SamD]

Much respect to the cooler boxes / cold fingers people have made, but I found that my DIY Peltier cooled box only managed about -10C on ambient.

However, I can get about the same -10C cooling in Brisbane climate by putting a freezy ice block (the rectangular kind you put in lunchboxes) on the back. Couple of rubber bands to secure, and a shell of encasing polystyrene to insulate. Lasts for about 3 hrs on 15-20C nights. It less wires and a lot quicker to make !

For my purposes, this gets my 450D cool enough so that thermal noise is not such a big problem on the warmer nights, (remember the thermal signal halves every 5-6C). As to how cold is cold enough, you need to consider how much light pollution there is, and what f ratio you are imaging at. The idea is to cool enough so that thermal noise is less than noise from light pollution.

[ZeroID]

Ha ! what a 'cool' idea ( sorry, bad pun :rolleyes: ). Must give that a go on the ZWO. The Alum back is much closer to the sensor and the body smaller than a DSLR so cool down and effect should be better. I've just gone and bought a small peltier element but this is worth a try regardless.

Thanks :thumbsup: