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royterr
11-05-2009, 05:45 AM
i now that hd and full hd standards are meant to be played at 50 or 60 FPS.
But what if it plays at 24 or 30 fps, what will be the drawbacks?

phix314
11-05-2009, 06:53 AM
I've never heard such claims... I would guess the same thing as if you were to run 30fps at 18fps.. choppier motion. But at those numbers, I can't imagine there being any real drawbacks.

royterr
11-05-2009, 03:18 PM
I've never heard such claims... I would guess the same thing as if you were to run 30fps at 18fps.. choppier motion. But at those numbers, I can't imagine there being any real drawbacks.

so no difference to the hunan eye between 24 and 50 fps?

scrimski
11-05-2009, 03:59 PM
50 and 60 fps usually refer to interlaced footage and are the interlaced equivalent to 25p and 30p (p for progressive). And there is of course a slight noticable difference between 24 fps and 50 fps, the latter will look smoother, more videolike.
24 fps is usually run on cinematic projector, 25P or 50i is a PAL framerate used in Europe.

InfernalDarkness
11-05-2009, 07:10 PM
Scrimski is correct.

That said, "the human eye" varies from person to person, but still has a framerate equivalent to the amount of sensors IN the eye, which are millions. One could definitely notice the difference betwee 15fps, 30fps, and 60fps, but most monitors top out at 60Hz anyway, so going above 60 isn't really desirable.

From Wiki:

The number of frames or fields per second. The 720p60 format is 1280 720 pixels (http://en.wikipedia.org/wiki/Pixel), progressive encoding with 60 frames per second (60 Hz (http://en.wikipedia.org/wiki/Hertz)). The 1080i50 format is 1920 1080 pixels, interlaced encoding with 50 fields per second. Sometimes interlaced fields are called half-frames, but they are not, because two fields of one frame are temporally shifted; video engineers use the term 'picture' instead. Frame pulldown (http://en.wikipedia.org/wiki/Telecine) and segmented frames are special techniques that allow transmitting full frames by means of interlaced video stream.


If you're looking for motion-film information about resolution, this page (http://en.wikipedia.org/wiki/Movie_projector) should help.

Modern shutters are designed with a flicker-rate of two times (48 Hz) or even sometimes three times (72 Hz) the frame rate of the film, so as to reduce the perception of screen flickering. (See Frame rate (http://en.wikipedia.org/wiki/Frame_rate) and Flicker fusion threshold (http://en.wikipedia.org/wiki/Flicker_fusion_threshold).) Higher rate shutters are less light efficient, requiring more powerful light sources for the same light on screen.

kyleb2112
11-06-2009, 03:43 AM
It's very important you know the format it will be played on and plan accordingly. If you render 24 fps and you (or someone else) converts it to 29.97 fps, you could get a double frame every 6th frame or so, making for a stuttering playback. I see this all the time even on TV commercials. Same kind of problems going from PAL to NTSC frame rates. There are ways to convert all these frame rates without doubling frames, but video editing softwares don't typically do it automatically, and you'll get those doubled frames if you're not careful.

phix314
11-06-2009, 06:16 PM
so no difference to the hunan eye between 24 and 50 fps?
Note: "Drawbacks" is not "difference".

Personally, I can't stand the 120hz HD motion. Too fluid. I'm more partial to the 24p cinematic look.

royterr
11-06-2009, 07:50 PM
so there's no standard, it could be 24 30 50 60 FPS.

lostparanoia
11-07-2009, 01:07 PM
so there's no standard, it could be 24 30 50 60 FPS.

Yes, those are the standards. 24p is for cinema. 25p or 50i is pal framerate, 30p or 60i is ntsc framerate. you should adjust your framerate according to the type of media it will be shown in. Otherwise it will look like crap, basically. :)

JasonA
11-13-2009, 06:09 PM
If I know i intend to show the clips on dvd, then ill render at 24fps and author it that way as well. The dvd player will perform the telecine (2:3 Pulldown) if nessesary, although honestly who uses a non-progressive displays these days?

InfernalDarkness
11-13-2009, 06:28 PM
although honestly who uses a non-progressive displays these days?

Poor people who bought their monitors/TV's more than six months ago?
(smirks)






I don't even own a TV anymore. Cheap 22" LCD's all over the place do the job just fine. Regular TV's seem like a downgrade, really...

tharrell
11-13-2009, 07:27 PM
so there's no standard, it could be 24 30 50 60 FPS.

Be very very careful when you use the term FPS. It's ambiguous.

At 24, 29.97 or 30, it generally means frames per second.

At 48, 50 or 60, it generally means fields per second (a field is 1/2 of the vertical lines in a frame).

So, to clarify:

60 fields per second is an interlaced version of 30 frames per second.

When doing HD, I prefer rendering progressive 24p (NTSC) then converting to 25p (PAL). You can do a 3:2 pulldown or a reverse in most professional editing software to go to 30/29.97 and back, and you end up with fewer frames to render... and at HD it's usually a pretty substantial difference in rendering time (24 fps 1080p vs 30 fps 1080p, for example).

--T

royterr
11-13-2009, 09:14 PM
Be very very careful when you use the term FPS. It's ambiguous.

At 24, 29.97 or 30, it generally means frames per second.

At 48, 50 or 60, it generally means fields per second (a field is 1/2 of the vertical lines in a frame).

So, to clarify:

60 fields per second is an interlaced version of 30 frames per second.

When doing HD, I prefer rendering progressive 24p (NTSC) then converting to 25p (PAL). You can do a 3:2 pulldown or a reverse in most professional editing software to go to 30/29.97 and back, and you end up with fewer frames to render... and at HD it's usually a pretty substantial difference in rendering time (24 fps 1080p vs 30 fps 1080p, for example).

--T

ok so always render 24 fps and convert to 30 fps in post if needed. never 50 frames or 60 because its generally useless

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