The HD33 is a simple projector in the best possible way. The HD33 has a tight, laser focus on what really matters--picture quality. It has this in spades.
Picture Quality in 2D. Like the HD20, the HD33 offers great picture quality for 2D theater in both standard and high definition. Dynamic range is solid, with sparkling highlights and black level comparable to the competition in this price range. Color is vibrant and saturated, and grayscale tracking is already close to the ideal 6500K straight out of the box. Some fine-tuning can coax additional performance out of the projector should you desire, and the end result is near perfect 6500K across the board. Detail clarity is superb, though the projector shows some signs of digital noise and DLP dithering that can detract from the otherwise natural feel of the image. This noise is especially evident in large swathes of solid color, such as a sky. That said, noise was no worse than other projectors in this price range; all of them show digital noise to some degree.
Picture Quality in 3D. Everything that is true of the HD33 in 2D is equally true in 3D. If anything, the 3D glasses help the projector's black level appear even deeper, which makes the picture look higher in contrast. Highlights, sometimes too bright in 2D, are brought down to a more manageable level due to the glasses. While the glasses reduce the brightness of black and white equally, your mind is fooled into seeing an image that looks higher in contrast due to the better black. The other noteworthy quality is the HD33's near absence of crosstalk. Even in the most difficult scenes, the HD33 did a remarkable job of keeping left-eye and right-eye images separate and distinct. This, more than anything, contributes to the high-quality, professional feel of 3D.
The Optoma HD33 Connection Panel
PureMotion. The HD33 also includes PureMotion, a frame interpolation system used to reduce judder. It has three settings, each more aggressive than the last. There is some digital video effect, more so on the higher settings. This is desirable for live performances and television and less desirable for film. What's more, PureMotion can be activated in 3D, making the 3D picture appear less jerky. This is especially helpful when watching fast action sequences, such as those in Avatar.
RF Glasses. To our knowledge, the HD33 is the first 3D projector to use an RF emitter to sync the glasses to the projector. Radio has several advantages over IR, not the least of which is that it does not require line of sight between emitter and glasses. This means your glasses will never lose sync because you looked too far to one side, or turned your head to talk to a friend, or looked down to find the remote. It is also much simpler to calculate range when using RF glasses, as one does not need to worry about bouncing the image off of the screen or mounting the emitter in an easily visible place. Simply place the emitter next to the projector and it should work just fine, provided the audience is within about 10 meters.
The downside is that the glasses won't turn themselves off unless the projector is no longer displaying 3D, so it can be easy to run down the batteries accidentally. The HD33 comes with the emitter. The glasses are purchased separately and additional pairs cost less than $100. The glasses fit well and have large lenses, so those who already wear glasses should be able to use them without issue.