Cooling various models of Canon DSLRs

[Gina]

Following my experiments with debayering various Canon EOS models I shall be looking at adding cold fingers and cooling. I have already covered the 1100D in my various 1100D cooling threads so this is for the others. I have a 300D on it's way and 350D and 1000D that I have so far been unsuccessful in bebayering but expect to buy faulty ones for the sensors to try again. Meanwhile, I can take photos to show the possibilities of the camera models I have at present.

[Gina]

350D location of cold finger.

These photos start with the rear view of the camera stripped down as far as the sensor. With the PCB containing the video output removed there is a clear way out from the back of the sensor to the left hand side (as seen from the back of the camera). There is also a gap of over a millimetre between the sensor and the screens on the main board as can be seen in the other two photos. The copper sensor retaining clips would be removed and the cold finger used to hold the sensor in place with the original clip screws in recessed holes in the cold finger.

[Gina]

I've measured the gap between the sensor and the main board screens and it's 1.6mm so 1.2mm (18swg) copper sheet would be fine, allowing for a thin sheet of insulation between cold finger and screens.

[Gina]

1000D works without back for USB connection & PC so can have similar cooling to the 1100D.

[frjaraur]

Hi Gina,

I have learned a lot from your posts, Many Thanks!!!.

I am trying to cool my 1000D using some of your ideas, but can not power on 1000D without back tape. I have taken off display because I am trying to cool from the back (loosing display option).....what do you think about this approach for cooling?

Many thanks,

Javier R.

Enviado desde mi LG-P760 usando Tapatalk 2

[Gina]

It's the way I do it.  I know it works with the 1100D and 450D and it seems I tested the 1000D without the back.  I  can't remember about the 1000D now but most want the battery flap closed to power up.  Maybe that's your problem.

[frjaraur]

Hi Gina,

You are probably true. I couldn't try it, but I will check this weekend .

One thing that really worries me is insulation.... I would like to maintain original EOS case and I didn't put cupper plate near the sensosr, it just reached the aluminium plate covering the sensor circuit. Do you think that it could be cooling enough? or I should reach the sensor's back as you did?

I am waiting for a new peltier because the one I bought just reach a 9 degrees delta :|

Many Thanks for Your Help,

Javier R.

[Gina]

Some moderate results have been achieved by cooling the whole camera but I didn't get very good results.  It wasn't until I used a cold finger (copper strip onto the back of the sensor) that I could get the temperature really low.  I'm afraid I didn't succeed with keeping the original case due to condensation problems.  I only got sustainable low temperatures (well below freezing) when I used a separate box that could be sealed and dried with desiccant (silica gel).  However, there are some designs that use a sealed chamber close around the sensor that retain the original case with the cooler out to one sdie.

I'm still working on two cameras - covered in two other threads in this forum - an 1100D with full spectrum mod and set-point cooling and a 450D converted to mono and including a filter wheel within the outer case also full spectrum and set-point cooled.

[frjaraur]

Many thanks Gina,

I will try this weekend and let you know. I am very worried about isolation. ...... :S

Javier R.

Enviado desde mi LG-P760 usando Tapatalk 2

[frjaraur]

I forgot to tell you that with my peltier cells I just can reach 9°C oferta delta. ......and it is not enclosed inside my 1000D yet. .. :S .... even using CPU cooling....

I am waiting for a double side TEC for this project.

Regards,

Javier R.

Enviado desde mi LG-P760 usando Tapatalk 2

[frjaraur]

Does anyone have interference problems with peltier?.... I closed yesterday my modded 1000D, without display and peltier over the aluminium piece and I get horizontal lines on my darks taken with peltier running. ...

And the main problem is that a customized sensor next to aluminium piece says 3°C althouhgt canon sensor says 19°C.... I can not belive such a difference. ...

Many thanks for your help.

Javier R.

Enviado desde mi LG-P760 usando Tapatalk 2

[Gina]

Interference from the sharp edges of the square wave PWM power supply to the peltier is the reason I added RFI suppression to the power feed.  A choke (inductor) consisting of a few turns of wire through a ferrite ring and ceramic capacitor (10nF).

The Canon temperature sensor is in the image processing chip which runs considerably warmer than the sensor when Peltier cooled.  That's another reason for measuring cold temperature as close to the image sensor as possible (on the cold finger) - the other is to provide feedback for set point cooling.

[frjaraur]

Many Thanks Gina,

I will try your solution to avoid interferences

I want to show you how my mod is going on .... 

This is how it looks before putting the cooling system...

I made display´s hole bigger for assembling there peltier over a thin cooper piece and this over the aluminium enclosure. I put the temperature sensor next to aluminium enclosure to check for cooling system's temperature with arduino.

Inside camera I used a tape usually used for cooling Air conditioning (but I think I should use some silica gel too :| )

On top of peltier I put a CPU cooling system (heat sink with fan).

I powered each one (fan and peltier) with 12V PWM.... 

This is how is my 1000D mod at the moment....

Many Thanks for your help Gina,

Javier R.