I have been 'away' from the projection world for a few years and the last one I owned was an Infocus Screenplay 7205 which was a fine Home Cinema Projector lacking only in absolute black levels. I have recently found myself in a position to get back into projection (new house/new room) and was looking for a decent projector on a limited budget. The Optoma appeared to fit the bill being well specified for a very good price. So having set it up, these were my initial thoughts.....
Firstly, it is tiny! With a footprint smaller than an A4 sheet of paper, it would easily sit on a bookshelf if you prefered not to ceiling mount. It could go on a coffee table but as the height of the projector represents the bottom of the image, you may want it a little higher so as to avoid using digital keystone correction (artificially 'squaring' up the image on the screen) which lowers image quality.
Quickly setting the image to CINEMA mode, putting the BRILLIANT COLOUR setting to +5 (0 is off, +10 is maximum) and checking the lamp was on normal and not bright I stuck on an HDMI connected Blu-Ray of 'Avatar' and was greeted by a vibrant, highly detailed and terrifically contrasty image. Blacks were brilliant and far better than I remember the Infocus having. Colours where rich without looking overblown and the image had great 'snap'. The Rainbow Effect (flashes of the primary colours when the eyes flick from side to side of the image caused by the spinning colour wheel) where not severe in my opinion but different people are affected on different levels of severity by this so I can't say for sure that it won't be a problem for you. It was certainly no worse than my previous Infocus.
It is marketed as being 3D Ready but currently it will only work with a specific NVidia graphics card equipped PC and NOT with Sky 3D or Blu-Ray 3D. But sometime in early 2011 (Jan/Feb is quoted by Optoma) you will be able to purchase a seperate '3D-XL Adaptor Box' (£249 on Amazon) which looks a little like a thin, black DVD player and daisychains between your source (Sky3D or BluRay) and the projector to give full 3D compatibility. This is still a very cheap way into 3D projection and far cheaper than most 50" 3D TV's
Moving on, I then tried the Pixar movie 'UP' and it was here that I noticed a problem.
With the Brilliant Colour set to middle (+5)(Brilliant Colour introduces an additonal cyan, magenta, and yellow section to the colour wheel's usual red green and blue to boost colour in all tones) I noticed a lot of video noise in areas such as the sky. Instead of smooth gradient transitions, you get flares of colour and steps of shades. Reducing the Brilliant Colour setting reduces this problem and obviously increasing it makes it worse, but when lowering it, you also loose much of the 'snap' to the image I mentioned earlier.
The Brilliant Colour setting does give massive contrast improvements to the image and without it the image looks a little flat but these image artifacts are very distracting when they appear.
Saying that, for many if not most movies you'll probably not notice any problems, just cracking images. But it is this issue which led me to give only 4 stars out of five. For the money, the Optoma HD600X is a great buy, but don't expect reference standards from this budget PJ. As a first step into the projection waters, it's fine but if you are looking to get image perfection on a 100" screen, look elsewhere!