Are Blu-Ray Discs faithful to original frame rates of the source material?

[Karim D. Ghantous]

I don't own very many BRDs and I only recently got a more modern TV (a 42" Plasma from 2007!). So, back in the day, before DVDs, if you wanted the best possible LaserDiscs you'd want the NTSC ones. Yeah they had the 3:2 pulldown, but they were more authentic to the original frame rate, i.e. 24fps. PAL discs had more resolution but the frame rate was off. Also, IIRC, the NTSC discs were better mastered.

So I got to wondering if all BRDs preserve 24fps? I found this:

NTSC and PAL use different FPS (frames per second) rates. But the Blu-ray specification clearly defines what frame rates players must support. All PAL players must support frame rates of 23.976, 24, 24.97, 25, 29.97, 30, 59.94, and 60 but NTSC only need to support 23.976, 24, 29.97, 30, 59.94, and 60 fps.

https://support.discmakers.com/hc/e...-worry-about-NTSC-and-PAL-with-Blu-ray-discs-

Some publishers might be lazy and just print PAL BRDs with 25fps. Is there a way to tell? Which review websites talk about these things?

 

[Marc Wielage]

Some publishers might be lazy and just print PAL BRDs with 25fps. Is there a way to tell? Which review websites talk about these things?

25fps discs have kind of a "look" to them, and as far as I know most Blu-rays are 24fps (or 23.976fps). Blu-ray.com would be one review site with useful information.

 

[Blair S. Paulsen]

Unless a project is produced specifically for PAL broadcast, odds are very high it was shot at 23.98/24 or possibly 29.97/30. AFAIK, the BRD player itself takes the native content (24fps typically) and retimes it as needed for whatever output standards it supports. IIRC, one of the drivers of putting native 24fps onto optical discs rather than a 29.97/30 was data capacity and compression issues. Moreover, I would imagine that the companies authoring and productizing home video releases did not want the extra cost and potential dead inventory of making multiple versions.

If you really wanted to see if either PAL or ATSC presentations of the same BRD looked different, you could setup side by side monitors. Of course that test is useless, unless you can defeat all that lovely motion "smoothing" common to newer display tech ;-)

Cheers - #19