Mass Media & Technology

25, 30, 60 Frames Per Second

Will we ever be able to capture motion in it's truest form? (December 2016)

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VM
VMPhil
Surelt the fact that nobody takes any issue with the fact the soaps are 50i (and in fact viewers took issue the times they've tried to change it) shows that there's nothing wrong with it at all as a format, even for dramatic productions?

Shame TV producers don't seem to think that these days, where it seems even your cheap daytime property show, or even a documentry consisting of talking heads HAS to be 25p.

.


I'm not, and never been a fan of 25p, but I do concede it can be preferable in some cases. What is awful are things like Sony's 'Motionflow' that attempt to convert 25p into 50i style 'fluidity', on modern flat screens

I find I have to spend quite a bit of time with a new TV turning off all those features, and turning off the overscan which is always on by default.
MA
Markymark
Surelt the fact that nobody takes any issue with the fact the soaps are 50i (and in fact viewers took issue the times they've tried to change it) shows that there's nothing wrong with it at all as a format, even for dramatic productions?

Shame TV producers don't seem to think that these days, where it seems even your cheap daytime property show, or even a documentry consisting of talking heads HAS to be 25p.

.


I'm not, and never been a fan of 25p, but I do concede it can be preferable in some cases. What is awful are things like Sony's 'Motionflow' that attempt to convert 25p into 50i style 'fluidity', on modern flat screens

I find I have to spend quite a bit of time with a new TV turning off all those features, and turning off the overscan which is always on by default.


Ha, good !! Thumbs up

On my 5 year old Sony all that stuff has to be switched off separately for each input socket, or source, and removing overscan on the internal TV tuner has to be done with the HD broadcast in 50i and 25p mode (which of course changes dynamically according to the encoder at the broadcaster), you don't realise until a programme comes on that switches regularly between the two, and the picture jumps in and out of overscan ! I trust newer models have fixed that issue ?
JA
james-2001
What is awful are things like Sony's 'Motionflow' that attempt to convert 25p into 50i style 'fluidity', on modern flat screens


It's fairly obvious that trying to interpolate fake frames on the fly is never going to look good! It's usually uneven and on-and-off and looks dire.

Sadly even THAT seems to have clogged people's view of higher frame rates, I remember much of the critisism of The Hobbit (again- much of which came before the people critisising it had even seen it) was based around it looking like awful TV motion smoothing. Either that or a 70s BBC costume drama. Which it obviously didn't, but people had decided they hated it before they'd seen a frame, so it was doomed from the start.
NG
noggin Founding member
What is awful are things like Sony's 'Motionflow' that attempt to convert 25p into 50i style 'fluidity', on modern flat screens


It's fairly obvious that trying to interpolate fake frames on the fly is never going to look good! It's usually uneven and on-and-off and looks dire.

Yep - breaks up on fast motion, patterns etc.

Also doesn't solve temporal aliasing issues. Wagon wheels will just appear to go backwards more smoothly - they won't go forwards...

Quote:

Sadly even THAT seems to have clogged people's view of higher frame rates, I remember much of the critisism of The Hobbit (again- much of which came before the people critisising it had even seen it) was based around it looking like awful TV motion smoothing. Either that or a 70s BBC costume drama. Which it obviously didn't, but people had decided they hated it before they'd seen a frame, so it was doomed from the start.


I didn't particularly enjoy the 48p in The Hobbit. It made the 3D nicer, but also showed up the visual effects a bit. Wonder if 180 rather than 270 degree shutter would have helped?
JA
james-2001
Possibly- I seem to remember they went for the 270 shutter partly to make sure the 24p version looked pretty much normal. Whereas if it was 180 then it would have looked too jerky. I guess having to shoot so that it still worked in 24fps restricted them in various things. I find it a bit unfortunate they didn't release the 48p version in 2D though- or for DVD, Blu-Ray and TV showings (at the very least the typical 4% PAL speedup would put it up to 50p so easy to convert to 576i, 720p and 1080i- admittedly not sure how they'd have handled it in 60hz regions though).

One thing about The Hobbit is I guess it was the first major film to be made in such a format- so you could see the issues and imperfections as being part of a learning curve, after all it took film makers a while to get the hang of sound, colour, digital, widescreen, 3D and other things (I've read about how the visual style of films pretty much took a step backwards on the introduction of sound while they learned the ropes and perfected the technology)- would have been the same with HFR if people were prepared to stick with it, tinker with it and learn how to work best with it, rather than declare it a "failed experiment" after a single trilogy of films.
Last edited by james-2001 on 20 December 2016 12:05am - 5 times in total
DA
davidhorman
James Cameron was talking quite forcefully about shooting future Avatar films at 60fps (then 48fps) shortly after the first film came out. Not sure if that's still the plan.

Ang Lee's Billy Lynn's Long Halftime Walk was shot at 120fps.

Quote:
The film's unconventional stereo 3D, 4K, 120fps shooting format generated a total of 540TB of video footage, and a final delivery file of 84TB.
VM
VMPhil

I'm not, and never been a fan of 25p, but I do concede it can be preferable in some cases. What is awful are things like Sony's 'Motionflow' that attempt to convert 25p into 50i style 'fluidity', on modern flat screens

I find I have to spend quite a bit of time with a new TV turning off all those features, and turning off the overscan which is always on by default.


Ha, good !! Thumbs up

On my 5 year old Sony all that stuff has to be switched off separately for each input socket, or source, and removing overscan on the internal TV tuner has to be done with the HD broadcast in 50i and 25p mode (which of course changes dynamically according to the encoder at the broadcaster), you don't realise until a programme comes on that switches regularly between the two, and the picture jumps in and out of overscan ! I trust newer models have fixed that issue ?

Yes I have a 2011 Sony too! And indeed you have to adjust the picture/screen settings for each input, which is a minor annoyance if you just want the same settings applied across all.


And of course it lets you choose 'Full Pixel' 1:1 on the Freeview HD channels, but doesn't let you do the same on the SD channels (just gives you a bit more of the picture). Luckily I have a set top box plugged in via HDMI so I just watch through that.

It was the first smart TV I bought, though I never bought it with the intention of ever using those features, and indeed it's apparently too old now to run YouTube which shows you how much of a farce smart TVs are. I have no intention of replacing it anytime soon.
DA
davidhorman
Quote:
And of course it lets you choose 'Full Pixel' 1:1 on the Freeview HD channels, but doesn't let you do the same on the SD channels


Well it couldn't be 1:1 anyway, obviously, but there's also the fact that as well as overscan, SD video is meant to have nominal analogue blanking. A 720x576 video doesn't have quite the aspect ratio you'd expect it to have, and should in fact be stretched a little beyond the left and right edges to be displayed correctly.

Your set top box will do the same, so you're still missing out on at least 16 glorious pixels (of probably black) per line.
JA
james-2001
Something I've learned when video editing and capturing, those extra 16 pixels on the side- means when you do a still capture of a video frame (or a square pixel video file ofr uplaoding to somewhere like YouTube) it needs to be 788 rather than 768 pixels wide for 4:3, and 1050 rather than 1024 for 16:9 to keep it in the correct shape. It depends on the source whether there's any picture in those additional pixels- they aren't always blank! Certainly my old Mini DV camcorder filled the whole 720 pixels, some stuff I've captured from digital TV does as well. And even on my transfers of VHS and 8mm tapes you see the head switching noise at the bottom of the frame expand into those pixels.
MA
Markymark
I find I have to spend quite a bit of time with a new TV turning off all those features, and turning off the overscan which is always on by default.


Ha, good !! Thumbs up

On my 5 year old Sony all that stuff has to be switched off separately for each input socket, or source, and removing overscan on the internal TV tuner has to be done with the HD broadcast in 50i and 25p mode (which of course changes dynamically according to the encoder at the broadcaster), you don't realise until a programme comes on that switches regularly between the two, and the picture jumps in and out of overscan ! I trust newer models have fixed that issue ?

Yes I have a 2011 Sony too! And indeed you have to adjust the picture/screen settings for each input, which is a minor annoyance if you just want the same settings applied across all.


And of course it lets you choose 'Full Pixel' 1:1 on the Freeview HD channels, but doesn't let you do the same on the SD channels (just gives you a bit more of the picture). Luckily I have a set top box plugged in via HDMI so I just watch through that.

It was the first smart TV I bought, though I never bought it with the intention of ever using those features, and indeed it's apparently too old now to run YouTube which shows you how much of a farce smart TVs are. I have no intention of replacing it anytime soon.


Yes, my one suddenly stopped supporting i-player, then there was an update, and it started supporting it again ! I'm glad of its ability to reorder and prune the Freeview LCNs, but it's so incredibly clunky
and long winded to do it. It's also very slow when you switch it on now too.

I get less 'overscan' on SD using the output from my YouView box, (as seen upscaled to 1080 by that) than SD on the internal tuner
VM
VMPhil
Quote:
And of course it lets you choose 'Full Pixel' 1:1 on the Freeview HD channels, but doesn't let you do the same on the SD channels


Well it couldn't be 1:1 anyway, obviously, but there's also the fact that as well as overscan, SD video is meant to have nominal analogue blanking. A 720x576 video doesn't have quite the aspect ratio you'd expect it to have, and should in fact be stretched a little beyond the left and right edges to be displayed correctly.

Your set top box will do the same, so you're still missing out on at least 16 glorious pixels (of probably black) per line.

Ah, well let me rephrase that to: when setting up a TV I try to get as little overscan as possible Wink And having it set to 'Full Pixel' on a HDMI input shows more on an SD channel than it does set to '+1' on Freeview SD as far as I can tell.
DB
dbl
My Samsung only allows me to turn off overscan on HD channels or sources, on SD it just crops off 8-10%

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