It is probably worth noting that unlike HDR10; Dolby Vision is a 12 bit format and not 10 bit. Dolby claims that those 12 bits are the equivalent of 14 bits.

Dolby Vision

@ Ronnie; I’m not sure about the LG OLED; but Panasonic claim that the DX900 is capable of 1000 nits brightness.

This currently is the maximum brightness that HDR content is being finished to; though potentially it could be brighter still in the future. The DX900 is not – AFAIK - Dolby Vision capable; so it would seem that the answer to your question would be to wait.

The conundrum as far as UHD/4K Television is concerned; is that OLED still produces the better blacks than any LED/LCD TV. But LED/LCD is capable of greater brightness than OLED; so which technology is the better one to exploit HDR is subject to debate.

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