The sharpness, brightness and contrast of this projector are above average and far above the quality of similarly priced projectors.
Of all the 1080p projectors I have seen so far, this one seems to offer the highest sharpness. With a previous 1080p projector we had, you could still see the pixels very clearly, but with this Optoma HZ40HDR it seemed as if the resolution was higher than 1080p. It was difficult to recognize individual pixels up close, even though the width of the projection on the wall was wider than 2 meters! This is also a projector that works well without having to darken your entire room. Of course, the image is always better in a darkened room, this applies to all projectors, but the light output is good enough without darkening.
Normally we project on a special screen from Elite Screens, but this projector even gave a good image on our white wall. Please note that you will need to adjust the white balance slightly for projecting on a white wall. Fortunately, this option is baked into the projector's options by default, so it's not a lot of work. And if you would like to tweak the image quality, you can go wild with all the options that the projector offers.
This is a Laser DLP projector, so there is a chance that with eye movements and moving images with a high contrast difference, you will see a kind of rainbow effect with a kind of rainbow light trail. Although this projector seems to be less intense than the previous DLP projectors we have had, it was still just a bit too much for us.
Besides the rainbow effect, which unfortunately bothered us a lot, the only other downside was the remote control. This has no rubber push buttons, but smooth flat membrane keys that are reminiscent of cheap remote controls that you get with an Action LED strip. It is a mystery to us why such a good projector comes with such a dilapidated remote control. For a few euros more, Optoma can certainly supply a normal remote control with rubber keys. With the smooth keys you cannot actually use the remote control by feel because there is almost no tactility.
All in all:
This is a fantastic projector if you are not sensitive to the rainbow effect that is unfortunately inherent to DLP projectors. Many people are not bothered by this, but for some people this can be a problem. If this is also the case for you, you might consider looking at projectors with 3LCD technology.