Peltier Cooling of Modified Canon Digital Rebel XSi (450D)

Version III

Detailed Assembly Instructions

Page 3 of 3

 

by Gary Honis


Page 3 of assembly instructions continued:

For the final steps we will be installing the small fan and insulating the cooler with styrofoam.

24. We will now pick up where we left off in Step 6 on Page 1. Connect the peltier wires, black to black and red to red and solder. I used heat shrink tubing to protect the connections.

25. Use small (red) plastic wall anchors and secure to fan with the four original fan screws. Push the fan with anchors into the heat sink fins to secure the fan as shown below:

26. Cut out foam pieces from styrofoam cooler using a hack saw blade as follows:

27. Place Front piece of cut styrofoam on front of cooling chamber and trace the T-ring hole and flash nosepiece hole. Use template made in Step 21 of Page 2 to mark the center hole for the hole saw drill bit. Cut a 2 1/4" hole in the styrofoam by turning the hole saw by hand. Remove the styrofoam to a depth of about 1/8" with a razor knife for the flash nose piece.

28. Apply a small amount of foam sealant into the gap between the peltier and aluminum chamber.

29. Using 5-minute epoxy, glue the cut foam pieces to the aluminum chamber to insulate it. Fill any small gaps with the foam sealant. After cured, trim any excess foam sealant that has expanded and fine sand smooth:

30. Drill a 1/4" hole through the styrofoam for the camera tripod socket. Test fit a 1/4 -20 size bolt for securing the camera. I use a 1 inch 1/4 - 20 thumbscrew and a large nylon washer.

31. When the Canon 450D is placed on the bottom of the aluminum cooling chamber, the camera's metal tripod socket does not come in direct contact with the aluminum chamber because the socket is recessed very slightly into the camera's plastic body. This is not good for thermal conductance, so I made a very thin washer by grinding down a small 5 mm washer. I applied a little thermal paste as well; it can't hurt.

32. Hot glue weather stripping to top of cooling chamber for a good seal. I used 3/4" wide by 3/16" thick vinyl foam weatherseal.

33. Now add an inner shield to the top styrofoam piece. To do this, cut a piece of styrofoam 3" by 6.5". Epoxy this inner shield to the top styrofoam piece and cover with aluminum tape. Trim the corner of this piece where wires will exit the cooling chamber from the camera:

34. To help seal the aluminum chamber, apply a piece of aluminum tape to the slot made in the chamber for the camera's flash nose piece:

35. Splice both fan wires to leads from the cool/off/warm switch and solder. I used shrink wrap tubing as shown:

36. Apply thermal paste around the thermal sticky pad of the blue round heatsink/fan as shown in the above photo. Clean the metal peltier support plate with denatured alcohol and secure the round fan into position with the sticky pad onto the support plate. Route the fan wires through gap in weatherstripping as shown below. I also added a wired temperature probe from a small indoor/outdoor battery powered digital thermometer.

37. Hot glue small blue fan wires to edge of heatsink as shown below:

38. Drill a 5/32 inch hole in corner of heatsink as shown. Use two plastic tie wraps to act as strain relief to secure the fan and peltier cables. Cut off ends of tie wraps.

Done!

Photo of completed camera cooler on scope below. I used a light-weight plastic split conduit as an organizer for the cables going to the camera cooler.

After you build a camera cooler, you can do dark frame and cooling tests. See the tests performed and results for my cooler HERE.

Some tips on using your camera cooler can be seen HERE.


First Light image of the Veil Nebula with the pelteir cooled Canon 450D can be seen HERE.


Removal of Canon DSLR IR Cut Filter for Astrophotography:


Google


To My Astrophotography & Digital Imaging Home Page

Canon DSLR 450D XSi Telescope Eyepiece Astronomy Astrophotography Meade Celestron Televue Eyepieces Telescopes