Canon A2400 IR conversion
The excellent tutorials for the various Canon PowerShot conversions inspired me to attempt a conversion of a Canon A2400. I chose this camera thinking that it would not be that much different than the others and because it is small and light and affordable at $80. Because I thought it wouldn't be much different, I wasn't as prepared to document the process but I quickly found out that it was in fact quite different than what I've seen and read about before. I was able to successfully complete the conversion with a functional camera, but I'll warn everyone up front: this might not be an ideal option until we can develop more community input on the best way to disassemble and reassemble it. The primary problem was that the lens and CCD assembly had to be removed and the ribbon cables detached. Hopefully the following notes and photos will help others improve on the process.
In other examples of IR conversion, some models could be modified with the front half of the case in place, but I had to remove it in this process.
There are six external screws to remove - two on the bottom, right, and left. One is under the USB cover.
With all the screws removed, remove back case (black) by carefully separating at the bottom and hinging at the top. You may need a fingernail or screwdriver to separate the top part. The back case has two rubber covers for the USB port and battery compartment (for external power supply). As you remove the front cover, note how their "tails" are looped over plastic pins on the front cover. Make sure you replace them correctly on reassembly.
Getting to the CCD
At this point I was expecting to just remove the back cover so I was removing every screw that made sense. The next series of photos will show most of these steps, but I'm not sure I captured all the details.
A thin metal plate sits in the LCD tray/frame. Remove this and remove all the screws in this area except the three recessed screws in the middle that have glue on them. These hold the CCD in place and will be removed later. At this point I still had the front cover loosely dangling but attached but it was connected by a little adhesive that held the shutter release wires to the front case.
At various points of the disassembly and reassembly, you'll need to lift edges of the button and sensor unit on the top of the camera and re-secure it. There are little plastic tabs that catch on the frame underneath. There is just one screw under a ribbon that will need to be removed in a later step.
At this point I'm still trying to figure out how to get inside this to get to the CCD. With so many screws out, the only thing holding the various parts together were the ribbon cables.
At this point, the other tutorials cover the details of removing and replacing the IR filter so I won't cover that here because it didn't seem to be different than other Canon camera models. The three screws on the CCD have glue but could be removed fairly easily.
Eventually the second ribbon cable of the lens unit slipped out while I was trying to reassemble. You will probably need to re-insert these a number of times so it's important to get comfortable with this. You can't just shove them back in. You have to lift the light brown plastic clamp that is on the back side of the ribbon jack, then slide the ribbon in, and lower the clamp. In this picture the CCD ribbon is out and the clamp for the CCD ribbon is up, ready for the ribbon to go in. The other ribbon is in with the clamp in the down position.
That was the last picture I took. I probably made a number of failed attempts to reassemble because the ribbons kept slipping out as I tried to fit everything back together. At this point I don't have enough experience to provide any more pointers on how to do this better, but it will take patience. All the various parts seemed to not quite fit well until I started to put the screws in and it all snugged together and became solid and like new. I do suggest that you start reassembly by ensuring that the CCD and lens unit cables are in place then carefully replace the screws into the metal tray on the back that hold the CCD unit to the frame. Once that is secure, you don't have to worry about those ribbon cables coming loose.
Questions and next steps
Hopefully these notes will serve as a starting point for someone else to find a better, more reliable way to make this conversion. We hope to conduct some NIR aerial surveys using this camera paired with an identical, but unmodified camera. If any problems or new information arises from that in relation to this conversion, I'll update this note.
Note: Originally I thought that my conversion "broke" the flash but today when I was trying it out, it worked so I've edited the note to reflect that. When I first thought the flash didn't work, I might have had the flash disabled, or maybe the capacitor had lost all charge when I was disassembling and didn't have time to charge when I immediately assembled and tested. In any case, the flash is working now, but the challenges of the detaching ribbon cables still remain.