The main picture quality assault comes on two fronts: black levels and what we'll call ‘purity', for want of a better description.
The black level angle is self-explanatory, simply referring to the unusually profound depths the IN78 manages to plumb while reproducing dark shots and scenes, such as those in the Nostromo's escape pod at the end of Alien. Most other projectors at this level - including the Optoma HD73 - exhibit far more greyness over black areas than the IN78, and as a result fail to deliver a picture with as much scale and immersive impact.
In terms of purity, we're talking about the IN78's uncanny knack with suppressing practically every type of video noise. These noise types start with those traditional DLP nemeses of the ‘rainbow effect' (where stripes of raw red, green and blue colour flit around the periphery of your vision) and fizzing noise over horizontal motion, especially if that motion involves skin tones. But we're also talking about general stuff like grain, dot crawl, and colour shimmer around edges.
By suffering so little with any of the above problems, the IN78's pictures allow you to form a direct bond with what you're watching to an extent that's seldom possible without spending megabucks.
Other contributions to the IN78's terrific pictures come from its vivid but unusually authentic colour palette, and a superbly judged presentation of HD detailing which ensures images always look sharp without going to such an extreme that pictures break down into looking forced, gritty and uncinematic, as can happen with less thoughtful projectors. It's worth adding, too, that the Pixelworks processing system earns its corn with standard definition sources, which are mapped to the HD Ready pixel count with rare aplomb.
Inevitably the IN78 does leave one or two reasons to consider spending more on a higher level projector. For instance, it runs a little more noisily than we'd ideally like. Also, although moving objects are largely free of DLP's dithering noise, they do still lose some resolution versus higher-spec projectors. Finally, you can of course get even better black levels if you splash more cash, particularly when it comes to the amount of shadow detailing retained in dark parts of the image.
Although we finished the main review on a negative note, we really can't stress enough just what great value the IN78 is. You'd probably have to spend not far off double its £1,475 asking price to get something substantially better, while in its own price bracket it's more or less in a class of its own.