The following are based on my 75"; YMMV.
Originally Posted by tonyjspr9
i do not have the equipment to test but supposedly setting contrast to 40-45 when watching hdr material will get the eotf closer to industry standards.
Yes, but you need to be careful if you don't have calibration equipment. If you lower Contrast too much, you'll end up below the EOTF curve on the lower (blacker) end. On my 75", setting Contrast to 43 is about the right spot. Lowering Contrast also improves color accuracy. But, caveat, it's unclear to me what impact it might have on tone mapping, particularly for >1000 nit content.
Originally Posted by ray0414
i also believe that turning gamma to -1 will also help the eotf curve because the picture becomes instantly less blown out looking.
I wouldn't recommend this, as it pulls you below the EOTF curve at the top, and makes color accuracy worse.
Another approach is to lower Backlight, but again you need to be careful, as lowering it too much will also put you below the EOTF curve on the lower end. On my 75", the break point is around Backlight 40. But, be aware that this approach is reducing the HDR max brightness. On mine, it dropped to ~1173 nits. Reducing Backlight also improves color accuracy. Lowering Backlight might have less of an impact on tone mapping than lowering Contrast; I don't know.
Attached are measurements for HDR (Movie, Warm2) at default settings, with Contrast 43, with Backlight 40, and with Gamma -1. No other calibration changes were made. Done with CalMAN Home for Samsung, SpectraCal C6 HDR2000, and VideoForge Pro.