[nibbleshifter]

That filter he removed is the IR cut, I believe. Not an anti aliasing filter.

The magenta hue you see in the outdoor shots is characteristic of photos taken using a sensor with no IR blocking filter (also known as a hot mirror).

[psychomugs]

Thanks, I felt like the term I was using was wrong.

[nibbleshifter]

How much effort was it to remove from the sensor? I've modified a number of cameras to remove that filter specifically for IR photography

[morcheeba]

You can probably replace this with a threaded IR cut filter that screws on to your lens.