Brightness auto increases to max on HDR

[Redpmac]

I have my tv set in filmmaker mode which sets brightness at 23.

When I watch something in HDR though, the brightness automatically increases to the maximum of 50 even though it’s still on filmmaker mode.

It’s not a major issue to turn it back down but I’m curious why it does this and whether I’m doing the right thing in turning the brightness down or should I be leaving it at 50 to get the best out of HDR?

[JAMES4578]

@Redpmac  HDR enables brighter highlights and a wider range of colours. To utilise the  full potential Brightness should be at the maximum level (thus it is automatically enabled), though the user is free to adjust.

A review of settings including HDR for one model here as a Guide  https://www.rtings.com/tv/reviews/samsung/s90c-oled/settings 

[Redpmac]

Thanks for your advice.  I’ll try it with brightness on max.