The DCS-930L is not designed for low-light usage. D-Link offers the DCS-932L Wireless N Day/Night Home Network Camera for that application. Unfortunately, it’s about $50 more than the DCS-930L from Newegg. Since I already had some IR LED assemblies, I wanted to see if I could make a DCS-930L infrared capable.
A quick test with a bright IR source proved that barely any IR was reaching the sensor, indicating a filter was in place. I pried the camera’s case apart by sliding a guitar pick between the front and back halves and began hunting for the filter. I was hoping it was attached to the front of the case and could be easily removed, but the case just has an open hole in front of the lens.
The lens was threaded onto the sensor assembly and secured with threadlocker. I unscrewed it with it pointed towards the ground to prevent loosened threadlocker from falling onto the sensor. The lens thread seems to be M5.5×0.35, and the threaded section is about 3 mm long.
Fortunately, the IR filter was immediately visible as the last (innermost) lens element. Using a hobby knife, I pried at the edges of the filter. It was glued all around its circumference. It eventually chipped and cracked, but this actually made it easier to pry out. I blew all the little glass shards out of the lens barrel, removed as much threadlocker from the threads as I could, and screwed the lens back into the sensor assembly.
When I powered the camera back up, it was clear that the filter removal was a success. The sensor is now very responsive to infrared light, which appears blue with a lot of ambient visible light, or white without (probably due to automatic white balance and color correction). As expected, some colors look unusual, such as green grass appearing light purple, or dark fabric appearing nearly white. The sensor is so sensitive to the IR range of the spectrum that some colors in the visible range are overpowered, and some materials are IR transparent. You’ll occasionally see reviewers complaining about infrared-capable cameras having washed-out colors for this reason.
An added bonus of breaking the lens threadlocker free is that the focus can be adjusted to suit the camera location. I just powered up the camera with the front of the case still removed and rotated the lens until I was satisfied.
I’ve removed the IR filters from most of my cameras. Coupled with IR LED assemblies, they are now working quite well in both day and night.
Update (11/26/2011): The last two DCS-930L cameras I ordered came with different lens/sensor assemblies. Rather than being threaded, the lenses are an integral part of the sensor assembly. Therefore, the simple IR modification above is not possible, and the focus cannot be changed. Intrepid folks might be able to dislodge the entire assembly from the PCB and perform a similar modification, but I am not going to try it.
Update (12/04/2013): Lars Englund was up to the challenge. Check out his blog post. User eljonco provides an alternative solution in his comment below.
Update (01/03/2017): I finally decided to try Lars Englund’s method for removing the lenses from the newer DCS-930L cameras I had ordered. When I opened one camera, the round front part of the lens assembly reminded me enough of the older threaded ones that I decided to try unscrewing it again. It worked. Apparently the threadlocker was just much stronger on the newer cameras than the older ones, once upon a time. Age and/or heat loosened it up enough that I was able to easily remove both cameras’ lenses. For a brand new DCS-930L, I wonder if applying gentle heat would be helpful, or if it would be sufficient to use two pairs of pliers, one to secure the square base, and one to twist the lens.