Originally Posted by Seegs108
Obviously there are diminished returns. I agree with that. I also think the RS400 has a massive advantage against the Sony 4K models. But you have to remember that the RS400 actually has less contrast available to it compared to last year's bottom end unit (X500). Unlike last year with the X500 and X700 the difference in native contrast performance is quite a bit different between the bottom and mid-tier unit. Only 21000:1 vs. 26000:1 at full brightness and the mid tier models both years remain north of 30000:1. So at full brightness we went from a roughly 16% difference to a 30%+ difference in native contrast between the bottom and mid-tier units at full brightness and this difference in contrast transitions even when you close down the iris more and more. So I don't think Kris Deering's quote is quite as appropriate as you think it is. With that said, yes, contrast is high enough on both models where it would take the right content to show that difference off. But with the iris closed on each to brightness match one another I think that darker content will definitely show an advantage on the RS500/600. Last year the units weren't really bright enough to close the iris most of the way down or fully and still get a decent peak white level on your typical screen size. That's not the case this year and for most, if they do close the iris way down, they can still get a decent peak white reading. So this year those crazy high native contrast numbers are actually usable for most people. The RS400 is limited to around 40000:1 and the other models can get above 100000:1 and still have enough brightness for most screens. With dark content this WILL show a difference. I agree black will look good on both units, I'm not arguing against that, but one will be more convincing than the other. This is also important for those who don't want to use the DI. I probably won't use it much and this extra native contrast boost will be very helpful in lieu of a dynamic iris engaged. This year, I really think there's a valid reason to buy the mid-tier unit whereas last year I didn't because the overall performance was extremely close between the bottom and mid-tier unit. The extra brightness this year means that those crazy high contrast claims can actually be utilized on normal to large size screens, whereas last year that wasn't really the case. There are definitely diminished returns, but I feel that this year you definitely get more for the extra money. JVC obviously created this contrast scenario on purpose this year as an overwhelming majority saw there was very little reason to with the mid and top tier models last year. Not the case this year.
But cine4home already indicated that for some set-ups, the RS400 will produce just as much or slightly more contrast than the X500. If one has a smaller screen and doesn't need as many lumens, the X500 would have more contrast, for example. Someone who needs more lumens and/or has a bigger screen might get a little more contrast or at least the same with the RS400.
And then one has to account for lamp aging. As the lamp fades on the X500, the iris will need more opening to maintain same lumens as before which will reduce the contrast over time where as the RS400 having so many more lumens (in reserve if you will) and will not be as affected by this or to the same degree with some set-ups. So, I would not say the X500 has more contrast than the RS400 despite the official spec as it has to be taken in context.
Whether some want to admit it or not, the bright corners issue is a greater problem on at least some RS500/600s so aside from the center, there will not be a massive contrast improvement. Some might prefer better uniformity with the RS400 and I haven't seen many complaining of bright corners on the RS400 (or the 2014 models for that matter). If one gets a perfectly uniform RS500, then perhaps they can get 120,000:1 (or whatever high number based on their set-up) across the screen but this is turning into a panel lottery it seems. It reminds me of the clouding issues on some of the LED flat panels where some were better than others.