These cameras started life as ordinary Philips ToUCam Pros, one with a Mogg adapter.  After an exciting flurry of messages on the QCUIAG list and about $5.00 worth of junk-box parts each, they turned into true long exposure cameras!  Steve Chambers had figured out a way to make it happen, and was gracious enough to share his discovery with us all (please see Steve Chambers' site for more details and official instructions!).

On this page I describe how I performed this long-exposure modification, specifically for the ToUCam Pro.  I modified two cameras:  One left in the original egg case and fitted with a switch to select between long-exposure mode and normal mode, and the other fixed as a long-exposure camera mounted in a custom box with Peltier cooling.  You can try the same thing yourself - BUT BE WARNED - IT IS POSSIBLE TO EASILY RUIN YOUR WEBCAM!!!  Consider carefully whether you really want to attempt this yourself.  If you do and you end up ruining your webcam, don't blame me!  You've been warned!!  A good "can I do this mod myself"-type of test is to take a look at 16510 chip on the camera board - see its tiny little pins?  Does the thought of manipulating and soldering these teeny-tiny little pins scare you?

Still reading?  Good!  Here is the circuit I used for both cameras, which according to Steve might work for any CCD camera using the 16510 chip (such as the Philips Vesta, Vesta Pro, and of course ToUCam Pro).  For the cooled camera, I omitted the switch and simply wired the 100K resistor to pin 10 on the 16510.

For my specific modification, the parts required for each camera, in addition to the ToUCam Pro, are:

• (1) SPDT switch
• (1) 74HC00 (quad NAND)
• (1) 100K Ohm resistor
• (1) 10K Ohm resistor
• (1) 470 Ohm resistor
• (1) Small piece of perf-board a bit larger than the 74HC00
• (1) Length of thin, two-conductor wire as long as the ToUCam Pro's cable
• (1) Small low-power-type coaxial plug and jack
• (1) Male 25-pin parallel port plug
• A handful of small cable ties
• A few small lengths of thin wire for connections

The first step is to pull off the camera legs (a little yank will do), and take apart the "egg":  Locate and remove the small hex screw near the cable.  This allows the little plastic cover plate to be removed.  The egg can then be split by holding the back half and sliding the front half towards the cable to release the two plastic tabs inside at the top that hold the halves together.  Then slide the cable strain relief from the back half.  To complete the disassembly, locate and remove the two small hex screws on the circuit board that bind the board to the front half.

*** Starting here, work on a grounded static mat and use a wrist strap! ***

Now the first of two tricky parts!  Locate the chip next to the CCD labeled D16510.  Three of its tiny pins must be lifted from their pads (namely pins 8, 10 and 13).  Get out your soldering iron with the smallest tip you can find (or grind), and some solder wick.  I found that by cutting the solder wick at a severe angle, the resulting point was fine enough to cover just the pin I was working on without disturbing the solder on adjacent pins.  Lay the wick on the target pin and heat the wick by briefly tapping the iron on it, removing as much solder as possible (two or three taps with a fresh wick tip each time should do for each pin).  Then using the tip of a triangular Exacto-type knife blade (or a dentists pick, etc.), apply very light outward pressure to the back of the middle of the pin to lift it while simultaneously touching the iron tip to the pin to melt the remaining solder holding it to its pad.  Once freed, the same blade can be used to apply an "around and up" pressure to the pin to gently bend it so it points upwards.  Be careful!  Those pins are very tiny and fragile and are easily broken!  (ask me how I know! :)  Be especially careful with pin 10 - it seems to be the most fragile.

The second tricky part involves attaching six thin wires to various locations.  The strands taken from some fine ribbon cable seem to work nicely here because they are thin and quite flexible.  I find that for this tiny soldering work, a toothpick can be used to apply tiny dots of solder flux to both the wires and the locations, and a small bit of solder on the tip of the iron is all that's needed to make a joint.  For the wires that attach to the pin solder pads, I find it easier to locate the traces to these pads and make joints to their vias rather than attempting to solder to the pads themselves.  The six wire attachments are:

1. Strip a length of insulation from the wire equal to the width of the 16510.  Lay it down across the 16510 so that the tip touches both pin 8 and pin 13 and carefully solder to both pins (this is "point C" on the schematic).
2. Solder a wire to pin 10 of the 16510 ("point E" on the schematic).
3. Solder a wire to the via that electrically connects with pins 8 and 13 ("point A" on the schematic).  It is located approximately as indicated on the diagram below - use a multimeter to verify you've found the correct via!
4. Solder a wire to the via that electrically connects with pin 10 ("point D" on the schematic).  It is located approximately as indicated on the diagram below - use a multimeter to verify you've found the correct via!
5. Solder a wire to the relatively large +5V pin next to the USB cable connector.  Flip the board over and see that the red wire from the USB cable is connected to this big pin.
6. Solder a wire to the relatively large GND pin next to the USB cable connector.  Flip the board over and see that the black wire closest to the red wire connects to this big pin.

Now time to check the work for shorting solder bridges, clean joints, etc. with a multimeter.  If everything's fine, great!  You're home free now!  It's a good idea to glue the wires down to the board so that the next steps that involve the other ends of the wires don't work the solder joints free with mechanical stresses.  Glue them down and set aside to completely dry.

The next bit involves wiring the right side of the circuit given in the diagram.  I used a piece of "perf board" cut so that two rows of perforations could surround the 74HC00 on all sides.  Insert the 74HC00 and bend its pins to grip the perf-board, and get busy making the circuit.  While going around the 74HC00 pins, make sure you reserve holes for the wires from the camera, parallel port, and switch.  For those pins that connect to a resistor, solder one leg of the resistor next to its pin and the other in an otherwise unused hole not next to any other pin, so that the relevant external wire(s) can be attached to the board as well.  Check your work for shorts, clean joints, etc.

Almost done now!  For the "original case" camera, cut a hole in the lower back half of the egg shell for the switch (there seems to be the most room here for a switch), and solder wires to its leads.  Drill a small hole in the lower back half of the egg shell for the long piece of 2-conductor wire, thread it, and attach the wire to the camera's cable with wire ties.  On the end that plugs into the PC, you can add a little plug and jack (like I did) or simply wire it directly to a male 25-pin parallel port plug.  Or you may choose to keep the 2-conductor wire free from the USB cable and install a plug/jack on the egg - whatever.

Finally, gather everything up and make the final connections from the 6 camera wires to the 74HC00 board, switch, and parallel port wires.  Start by bending the already glued wires around the side of the CCD board so they point backwards.  Reattach the CCD board to the front egg shell with the two little hex screws (before you do this, consider placing a little piece of black tape over the LED - it's quite bright and *will* add unwanted noise to long exposures!)  Lay a few strips of electrical tape on the back of the CCD board, to insulate it from the 74HC00 board.  Solder the wires to their respective locations.  Gently stuff it all down and reattach the back half of the egg.

All done!  All that's needed now is some video capture software (such as Steve's Desire program) to make it all work.  The software, in addition to grabbing frames from the USB camera, needs to twiddle the parallel port bit at the appropriate times to allow the additional logic to perform the long exposures.

For the cooled camera, there is more work to do.  Lacking proper metalworking tools and skills, I elected to assemble a cold finger using a stack of easily cut aluminum plates, with layers of thermal transfer paste in between each plate (crude, but seemingly effective!)  The CCD is removed from the circuit board, outfitted with about 4" of ribbon cable on each side, and buried in a slot in the stack of aluminum plates.  The aluminum plates with CCD are stacked on the Peltier device, which in turn is in contact with a Pentium heatsink and fan.  A .965" barrel and barrel holder from a camera adapter is used as a makeshift CCD chamber, and is held in place and applies pressure to the stack of aluminum plates, with three long screws and washers.

Here's a drawing of how the important stuff fits together:

Here's an exploded view of the previous drawing:

Now for some real pictures.  Unfortunately, I didn't document each stage, so hopefully what I did capture will get the general idea across.  Here's the assembly of the heatsink and Bud box lid.  The rectangular holes are cut just a bit larger than the Peltier device.  The blue plastic spacer is used to isolate the heatsink from the box lid.  Three sheet metal screws attach the pieces.  Note the two little notches in the box lid and spacer to accommodate the Peltier power wires:

Here's a shot of the CCD with the ribbon cables soldered to its leads wrapped with some electrical tape.  The second picture is of the prepared box, featuring a circular hole cut to fit the camera T-adapter I use, and a notch cut for the exit of the camera wires:

Here's where I'm lacking some pictures of the next stages - oh well, some shots from various angles of the almost completed assembly will have to do...  First is a shot showing the circuit board with the ribbon cables soldered-in where the CCD used to sit.  The second is the stack of aluminum plates topped with the .965" barrel/holder, all pressed down with three more screws and washers:

Here's a view down the barrel.  For the top plate, a circular blank with a hole cut in it for the CCD to peek through is used to "mate" with the barrel holder.  The other two shots are just some more views.  One thing to note is that all plate-to-plate, plate-to-Peltier, and plate-to-barrel-holder contact surfaces are sanded flat and treated to a nice dose of thermal transfer paste.

Finally, time to wrap it all up.  Attach the fan to the heatsink, wire it and the Peltier to a pair of power wires, wrap the boards up with electrical tape, smoosh things down, and attach the box lid [good thing the box isn't made of see-through material - I'm not that proud of the insides]  Ready to power up!