This camera started life as ordinary Philips ToUCam Pro webcam.  After a recent announcement by Steve Chambers on the QCUIAG list regarding his latest 3.X webcam mods, the purchase of a Sony ICX424AL CCD from Framos, and some intricate soldering, it turned into a very sensitive long exposure camera, officially known as a ToUCamPro/SC3.2.  Thanks Steve for your hard work and willingness to share your modifications!

On this page I describe how I cooled and packaged this long-exposure camera.  Please note that the details of the actual electronic modifications required to create this and other 3.X-type SC webcams are only available on Steve's website, which requires agreement with Steve's very reasonable terms and conditions.  You can try the same thing yourself - BUT BE WARNED - IT IS POSSIBLE TO EASILY RUIN YOUR WEBCAM AND/OR CCD!!!  Consider carefully whether you really want to attempt this yourself.  If you do and you end up ruining your webcam or CCD, don't blame me!  You've been warned!!

For this camera, I decided to try a different cold finger design.  My previous attempts required relatively long CCD lead lengths, which introduced annoying interference.  Not horrible, but still bad enough to require limiting the gain settings I could use to 50% or less.  So with that constraint, and the constraint of not having a milling machine or lathe, I came up with this "cage-type" design that only requires 1/2" lead lengths and can be constructed with simple tools like a drill, Dremel tool, hacksaw, and metal files.

Figure 1 shows the cage.  A thick plate of aluminum serves as the base, with 2 L-shaped pieces bolted to it to support the top I-shaped piece of aluminum that in turn supports the CCD.  The holes for the two screws that attach the L-shaped pieces are countersunk so that the bottom of the plate is perfectly flat with no screw heads protruding.  The joints are made as flat as possible and coated with thermal transfer paste to encourage the "coldness to flow".  Pretty simple!

Figure 2 illustrates how the CCD is mounted, and how the ToUCamPro circuit board is caged.  First of all, the CCD is placed on the I-shaped piece (with thermal transfer paste in between), and a small hold-down made of aluminum with a window cut in it is bolted down over the CCD to hold it in place (*be careful* too much pressure can crack the CCD cover glass!)  Then the circuit board is inserted, and sits on a piece of foam (not shown) to raise it closer to the CCD legs.  Finally the CCD legs are soldered with very short pieces of wire to the circuit board.  I made the bolt holes in the hold-down plate and I-shaped piece larger than required so the position of the parts could be adjusted to make the CCD perfectly centered in the camera body.

Figure 1

Figure 2

Figure 3 shows how the heat sink, Peltier device, and muffin fan are attached.  The Peltier device (coated on both sides with more thermal transfer paste) is sandwiched between the cold finger base and heat sink, and held in place with four screws inserted through the plate and screwed into the heatsink.  And the muffin fan is simply screwed onto the opposite side with four more screws.  Note the fan is positioned so the air flows toward the heatsink.

Figure 4 shows the attachment of the previous assembly to the camera body base plate.  This is crafted from a 3" PVC pipe plug.  The square knob-thing that permits turning the plug has been cut off and discarded, leaving a square hole just large enough to allow the heat sink / fan to pass through.  Four more screws are used to attach the pipe plug to the heat sink.

Figure 3

Figure 4

Figure 5 shows the completed camera, sans the camera body cover.  To form an air-tight seal between the base of the heat sink and the base of the camera body base, I used some silicone sealant (commonly used to seal aquariums, etc.) around the seam.

Figure 6 shows the camera body cover.  It is crafted from a 3" to 2" PVC pipe bushing, with most of the 2" portion cut off and discarded.  After a bit of sanding of the inner lip of the remaining 2" portion, a sliver of 2" PVC pipe is press-fit into the opening.  Finally, a little T-threaded ring salvaged from a Pentax T-adapter is press-fit inside the 2" PVC pipe sliver.

Figure 5

Figure 6

Figure 7 shows how the camera body is attached to the camera assembly - 6 more screws driven in to the camera body base plate.  In order to insure the T-threaded ring would stay put, I put a big bead of epoxy glue over both sides of the rings and lip of the bushing, making sure no epoxy leaked over into the T-threads.

Figure 8 shows the completed camera!

Figure 7

Figure 8

Of course, these drawings don't show the real mess!  The following pictures show various angles of the completed camera.  Red tape covers and insulates the ToUCamPro circuit board, while the green tape does the same for the "mod board".  The two rubber bands stretched around the rim of the camera body base plate are there to make a tighter seal with the camera body cover, since it was not a perfect fit.   And of course wires, wires, wires!  [NOTE: the blotted-out portions in the images are there to prevent any hint of Steve's mod - I don't want to violate my agreement with him!]

For the USB connections, I used a little 4-pin connector on the camera side, and a little 5-pin connector for the parallel port connections (the different pin counts help prevent connector mismatches in the dark!)  The Peltier device and fan are connected in parallel to a 12VDC/2A power supply via an RCA connector.  Finally, a little SPDT switch is used to switch between normal and long-exposure modes.

Not shown is some little pieces of foam insulation wrapped around the innards and placed over the top - this helps keep the cool where it should be.  Not shown either is the three-cable bundle that connects USB, parallel port, and 12VDC power source.  I used a big ferrite bead around the USB and parallel port cables on the end nearest the PC - it does work to reduce the interference seen at high gain levels!

So now the fun part of making the camera is done, now comes the fun part of seeing what faint fuzzies I can grab with this wunder-cam!  Stay tuned and see the results to be posted on my image pages.  [I'd have been out tonight if it weren't for the 30mph wind-gusts, but it did gave me a chance to put this page together..]