Black level performance2
In the image immediately below, you can see that the blacks on the Epson (left) are a bit brighter than the JVC on a black screen. If you saw the similar comparison in the IN83 vs RS20 comparison, you'll understand how good the Epson is for its price. Both the 6500UB and RS20 projectors were adjusted for brightness based on a bright scene. One of the drawbacks to dynamic irises, is that the companies set them to compromise the brightest areas slightly, so that the iris can do its thing. Otherwise, a single, tiny white area would require the iris to stay fully open.
Click to enlarge. So close. Doing this, ultimately results in some compression of the bright areas, if there is just a very small bright area. The result is a little less dynamic range. You can see the results of that in looking at the pause icon in the lower left. On bright scenes, they are the same brightness, but on a scene similar to this (mostly extremely dark with a very small white area), you can see that the JVC, while still providing slightly blacker blacks, will have "whiter whites" as well. The bottom line - a more dynamic looking image on dark scenes, while still having blacker blacks!
Click to enlarge. So close. From The Dark Knight, is slightly overexposed. Click on it for a larger, even more overexposed version. You can clearly see the differences in this medium scene (there is sufficient bright light to prevent the Epson's dynamic iris from closing down significantly).
Still the Epson does a pretty impressive job, considering how excellent the almost 3x the price, JVC RS20 performs.
Neither projector fits into the "very best" performance levels in terms of revealing dark shadow detail. I have to say these two are extremely close, and a tie, overall.
Look to the enlarged image above, as well as this dusk/skyscraper/SWAT van
Overall Look and Feel of the Picture
The JVC is just excellent overall, in terms of look and feel. I've seen other projectors that demonstrate a little more pop and wow, but the JVC, with its lumens to spare, in best mode, should still be more impressive, simply because most "pop and wow" specialists, like the Epson Home Cinema 6500UB / Pro Cinema 7500UB, aren't as bright. As a result, in a typical environment, in best modes, the JVC and the Epson aren't that different in terms of the dynamic look to the image.
I take it back! There is one area where the Epson Home Cinema 6500UB bests the JVC DLA-RS20: HDTV! That would be for viewing sports and general HDTV. Combine the Epson's dynamic look, and its still pretty good color accuracy, with tons of lumens in LivingRoom mode (or less accurate colors, but even more lumens in Dynamic mode) and the Epson is just more spectacular, and especially for sports viewing! The more controlled ambient light you want, the more the Epson outperforms the JVC, which has barely half the lumens in its brightest mode. Oh, the JVC will still have a more natural skin tone, but do you really care when watching an interception with 12 seconds left on the clock. I think not!
Bottom Line in terms of image quality
The bottom line, in this case, is the same as the top line: The Epson just can't match the JVC RS20, in most areas. The two are comparable in sharpness, and in shadow detail, but the JVC consistently has a definite, though not great advantage in terms of skin tones, black levels, and overall look and feel. On the bright side for those on tighter budgets, the Epson 6500UB - and 7500UB - come up awfully close considering they both sell for less than half the price of the RS20. And, again, the Epsons will typically be the better choice for sports viewing.