My grandkid snapped by my daughter. Photo taken with a Hutech-modded 40D, with a rectangular passband UV/IR Blocker over the sensor. Autofocused? Yes. It does work! Custom White Balance set on a white sheet of paper in bright morning sunlight thousands of miles away on the other side of the world, in a desert! Taken by somebody who had no clue as to how to use the camera. My daughter just picked up the camera and went clicking. Lens was a Canon 28-135mm IS that got included with the camera for a mere $200. And the message is? Custom White Balance in these modded cameras does a great job for most daylight and flash shooting, provided you have a rectangular passband UV/IR Blocker somewhere in the optical path (or an IDAS LPS). You really do not have to worry about it. And when you are under awkward lighting, eg tungsten, just use Raw and white-balance in post processing. Or simply repeat the 5-second setting of Custom White Balance before your sequence. The above was a Jpeg capture. Actually all colours come out very well and quite accurately, even when you compare the back-of-camera LCD review to your bouquet of flowers or whatever; except dark reds tend to come out much lighter. It's that extra oomph we chase for H-alpha. Eg the red strips in the above snap are in reality a darker shade than they appear here, but you did not know that, did you? ;-)