Click to enlarge. SO close
Rainbow Effect - DLP projector color wheel speed
Unlike some low cost DLP "powered" home theater projectors, the Optoma has a fast color filter wheel; 4x speed, and six segments. Now, the much more expensive DLP home theater projectors typically have a 5x wheel, but that is a minor difference compared to the 2x color filter wheels found on most low cost DLP projectors.
As a result, the rainbow effect should not be visible to the vast majority of viewers. There is no good published info out there as to what percentage of the population is bothered by the rainbow effect when viewing video on 2x, 3x, 4x or 5x color wheels, but lets say this, with a 4x or 5x wheel if you have yourself and 20 friends over for a movie, most likely none would see it, but maybe one person would be able to detect the rainbow effect, and that person, probably might see it only occasionally when moving their head, etc. In other words - don't worry about it. If you instead went with a DLP projector with a 2x wheel, a best guess is that one person in five to one in 10 people would see it. If it turns out that the H27 has a visible rainbow effect that bothers you, you've got a problem with DLP projectors, because it basically means that it is likely that you will not be able to enjoy any current model DLP projector, and will need to look to LCD projectors instead. Of course, the likelyhood of that happening is very remote. (Still its a good reason to buy from an authorized dealer that has some form of upgrade path that won't kill you with restocking fees.)