Hisense 65K680

[Anonymous]

Ok so surprise, surprise! I didn’t expect much from Hisense but one of my dealers started carrying it. There appears to be no user adjustable grayscale controls in it. I can’t seem to find anything online about grayscale adjustment. The one service code I tried didn’t work. So what’s the deal with these things?

This is their 4K TV. FYI it accepts 4K 24/25/30p at 4:2:2 and 4:4:4 for both 8 and 10 bit. It chokes and freezes on 2160p 50/60 @ 4:2:0 8 bit.

It treats 1080p and 2160p different. For 1080p it allows 0-255 for black level and white level setup but for 2160p it only shows 20-233 – everything else is clipped. But dig this: if you set black level using a 1080p signal, the brightness control’s black level adjustment is too coarse. Setting black level to match step 16 won’t work. One step will show 16 and below, and the next step down obliterates 17, 18, 19 with it so it will only show black at 20+. Since there is no picture memory setting for 1080p and 2160p, and the signal is different, we won’t see the same thing. The “correct setting” for black for 1080p will show only steps 25+ (steps 20-24 are hidden by the lower setting, with the TV clamping 19 and below if you were to actually raise the control). Of course if you tried to set black level using 2160p, the control needs to be raised, but then all 1080p info is washed out!

Sorry I’m writing while I’m multitasking with the sales guys and in front of the TV. Just writing notes for you before I forget!!

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[Anonymous]

I’ll also add that with a single-pixel checkerboard in 2160p, the TV flickers quite a bit. It doesn’t like it! HDMI input 1 is the only input that allows a 4K signal. Upconversion from 1080p and all other resolutions is pretty bad…lots of artefacts. 4K looks clean with my generator but I have no video to be sure. Probably best to have an A/V receiver or preamp do the 4K video upconverstion and feed that signal to the TV to bypass most of its processing. This should also solve the issue of different image settings for both signal types (since there is no memory per signal type). The set is retailing for CDN$2299. Not a bargain at all. Stay away.

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