> Send your XT to LifePixel (www.lifepixel.com). They'll swap out your > senser filter with an R87, or other specialty IR filter they sell. > You'll then be able to shoot 1/400 @f8 AND look through your viewfinder. > This has me thinking ! If an r87 filter has a compensation of, say, 8 or 16 steps, how come you can convert your camera, in which they place an r87 filter on the sensor, and then go about happy-shooting? My "reasoning" is that an r87 has a certain density, no matter if it is in front of the lens or behind it. So how can you shoot at higher speeds with a camera conversion, but not with a filter? **************** Alberto Tirado