The Sony KD-49X8309 has a maximum display resolution of 4K Ultra HD. That's over four times the display resolution of a Full HD TV, which is the most common display resolution. 4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
A 4K Ultra HD HD type is in fact the best display resolution amongst all TVs of a similar age and spec to the KD-49X8309.
The worst display resolution across similar types of TV is HD Ready.
4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
We compared this TV to all the other 4K Ultra HD TVs and we think the LG 40UF7707[plb_2940851_price], and the Samsung UE40JU6410[plb_2899172_price] which is cheaper is also worth considering.