HomeCinemaBanter

HomeCinemaBanter (http://www.homecinemabanter.com/index.php)
-   UK digital tv (http://www.homecinemabanter.com/forumdisplay.php?f=5)
-   -   24 fps, blue ray and my telly. (http://www.homecinemabanter.com/showthread.php?t=59979)

Adrian[_3_] August 25th 08 11:24 AM

24 fps, blue ray and my telly.
 
Alan wrote:
In message , Mike Henry
wrote

If you have all UK R2 titles however, you're stuck with them being at
25fps and the wrong speed and pitch forever no matter what player
you use, because the audio conversion was done at the DVD mastering
stage.


And isn't it amazing that 99.99 percent of the people buying these
DVDs haven't noticed?


Do you have any evidence to back that figure?



Roderick Stewart[_2_] August 25th 08 12:16 PM

24 fps, blue ray and my telly.
 
In article , Alan wrote:
If you have all UK R2 titles however, you're stuck with them being at
25fps and the wrong speed and pitch forever no matter what player you use,
because the audio conversion was done at the DVD mastering stage.


And isn't it amazing that 99.99 percent of the people buying these DVDs
haven't noticed?


I think it's curious that the effect has become known as "PAL speedup", even
though it's always been that way with any cinema film shown on European
television since before PAL was invented.

And you're right; most people don't notice. It bugs me that we should have
something inherently wrong built into something that is used by half the
world, but in real life there are more important things to worry about.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/


The dog from that film you saw August 25th 08 12:50 PM

24 fps, blue ray and my telly.
 

"Roderick Stewart" wrote in
message .myzen.co.uk...
In article , Alan wrote:
If you have all UK R2 titles however, you're stuck with them being at
25fps and the wrong speed and pitch forever no matter what player you
use,
because the audio conversion was done at the DVD mastering stage.


And isn't it amazing that 99.99 percent of the people buying these DVDs
haven't noticed?


I think it's curious that the effect has become known as "PAL speedup",
even
though it's always been that way with any cinema film shown on European
television since before PAL was invented.





what did we use before PAL ?


interestingly, visitng my parents yesterday i had to sit through the
godawful bridget jones 2.
all the music sounded quite normal - then i switched to the french
soundtrack for some reason - and the PAL speedup kicked in.
the people who did the dvd went to the trouble of pitch correcting the music
for the english soundtrack - so there's no reason why every company
shouldn't do the same.
fortunately while i spot the pitch shift straight away the tempo difference
which must have remained wasn't noticeable to me at all.



--
Gareth.

that fly...... is your magic wand....


Mark Carver August 25th 08 01:03 PM

24 fps, blue ray and my telly.
 
The dog from that film you saw wrote:

"Roderick Stewart" wrote in


I think it's curious that the effect has become known as "PAL
speedup", even
though it's always been that way with any cinema film shown on European
television since before PAL was invented.





what did we use before PAL ?


PAL is a colour coding system, before PAL (used first in 1967) everything in
western Europe was in black and white, i.e. no colour subcarrier. Of course
the France went their own way with SECAM.

You seem to be confusing CCIR 625/50, with PAL ?



--
Mark
Please replace invalid and invalid with gmx and net to reply.

Roderick Stewart[_2_] August 25th 08 04:02 PM

24 fps, blue ray and my telly.
 
In article , The dog from that film you
saw wrote:
I think it's curious that the effect has become known as "PAL speedup",
even
though it's always been that way with any cinema film shown on European
television since before PAL was invented.


what did we use before PAL ?


625 line 50 fields per second monochrome television. And before that, 405
line 50 fields per second monochrome television. I can remember seeing
cinema films shown on both systems. Telecine machines that can show film at
24fps did exist (and probably still do) but were not always used.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/


Johnny B Good August 26th 08 02:53 AM

24 fps, blue ray and my telly.
 
The message en.co.uk
from Roderick Stewart
contains these words:

In article , The dog from that film you
saw wrote:
I think it's curious that the effect has become known as "PAL speedup",
even
though it's always been that way with any cinema film shown on European
television since before PAL was invented.


what did we use before PAL ?


625 line 50 fields per second monochrome television. And before that, 405
line 50 fields per second monochrome television. I can remember seeing
cinema films shown on both systems. Telecine machines that can show film at
24fps did exist (and probably still do) but were not always used.


The results of any such 24fps telecine equipment, with the technology
available back then, would surely have been a less perfect solution than
that which is now used universally to display 24fps material at 25fps.

The one major drawback of raising the pitch by just over quarter of a
semitone was not a serious departure from fidelity. The 4.167% speed
increase would otherwise not be detectable without the aid of a
stopwatch and a knowledge of the running time of the 24fps material.

Another factor which helped endorse the rather pragmatic solution of
simply allowing 24fps film footage to be dragged through the telecine at
25fps was that the sound track would increase in pitch and sound
slightly 'sharper' which is far more acceptable than if the conversion
needed to go the other way and make the soundtrack sound 'flatter'.

The modest sharpening of the soundtrack is the least of any of the
other evils involved with alternative high tech conversion algorithms
that may have been entertained over the past 50 odd years. Although it
is now possible to shift the audio down in frequency to compensate, it's
not a good idea since it will upset the harmonic 'balance' and introduce
an even more objectional type of 'distortion'.

--
Regards, John.

Please remove the "ohggcyht" before replying.
The address has been munged to reject Spam-bots.


Roderick Stewart[_2_] August 26th 08 10:54 AM

24 fps, blue ray and my telly.
 
In article , Johnny B Good
wrote:
Telecine machines that can show film at
24fps did exist (and probably still do) but were not always used.


The results of any such 24fps telecine equipment, with the technology
available back then, would surely have been a less perfect solution than
that which is now used universally to display 24fps material at 25fps.


Not necessarily. All that's required is to be able to blend smoothly from
one film frame to the next so that individual film frames don't have to
coincide with TV frames. The fact that we do this sort of thing nowadays
by immensely complicated electronics doesn't mean it's the only way. By
suitable design, it can be done, and was done, optically.

In the 405 line monochrome 1950s the BBC had a programme called "In Town
Tonight" (the forerunner of what we would now call a chat show) which used
a variable speed telecine machine (Mechau?) to slow a film of London
traffic continuously from normal speed down to zero. I suppose this
gimmick was supposed to suggest that they were bringing London to a halt
while the programme took place. I never saw the machine but had it
described to me by someone who had operated it, and it appears to have
done its clever stuff by means of a rotating prism. The film would move
continuously (not intermittently), and the prism would rotate in such a
way as to present a varying blend of two adjacent film frames to the
flying-spot CRT, so there was no need for a shutter or any kind of
intermittent mechanism. It was a long time ago, but from personal
recollection the effect on screen was very smooth.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/


Roger Wilmut August 26th 08 11:44 AM

24 fps, blue ray and my telly.
 
In article en.co.uk,
Roderick Stewart wrote:

In article , Johnny B Good
wrote:
Telecine machines that can show film at
24fps did exist (and probably still do) but were not always used.


The results of any such 24fps telecine equipment, with the technology
available back then, would surely have been a less perfect solution than
that which is now used universally to display 24fps material at 25fps.


Not necessarily. All that's required is to be able to blend smoothly from
one film frame to the next so that individual film frames don't have to
coincide with TV frames. The fact that we do this sort of thing nowadays
by immensely complicated electronics doesn't mean it's the only way. By
suitable design, it can be done, and was done, optically.

In the 405 line monochrome 1950s the BBC had a programme called "In Town
Tonight" (the forerunner of what we would now call a chat show) which used
a variable speed telecine machine (Mechau?) to slow a film of London
traffic continuously from normal speed down to zero. I suppose this
gimmick was supposed to suggest that they were bringing London to a halt
while the programme took place. I never saw the machine but had it
described to me by someone who had operated it, and it appears to have
done its clever stuff by means of a rotating prism. The film would move
continuously (not intermittently), and the prism would rotate in such a
way as to present a varying blend of two adjacent film frames to the
flying-spot CRT, so there was no need for a shutter or any kind of
intermittent mechanism. It was a long time ago, but from personal
recollection the effect on screen was very smooth.

Rod.


The disadvantage of the prism-and-mirror system is that in effect it
crossfades one frame into the next. This results in some frames as
transmitted having double images where there is movement: something
which I can detect during viewing and find irritating. It's been used
occasionally, but not usually for full-length films (silent films are a
different problem, running as slow as 16fps). I did see a transmission
of 'Dr. Strangelove' where the BBC decided to repeat every 12th field,
producing a distinctly jerky effect on pans.

The 25fps solution is the least worst. Apart from the occasional person
with perfect pitch, the 4% (2/3 semitone) increase is barely
detectable. Oddly enough, a 4% drop (as with made for British TV films
shown in a cinema) is much more noticeable, producing a distinctly
sluggish sound.

Roderick Stewart[_2_] August 26th 08 11:53 PM

24 fps, blue ray and my telly.
 
In article , Roger Wilmut
wrote:
The 25fps solution is the least worst. Apart from the occasional person
with perfect pitch, the 4% (2/3 semitone) increase is barely
detectable. Oddly enough, a 4% drop (as with made for British TV films
shown in a cinema) is much more noticeable, producing a distinctly
sluggish sound.


Is there some technical reason why they can't show 25fps films in cinemas
at the right speed? Cameras can do several speeds quite easily just by
changing a crystal.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/


Roger Wilmut August 27th 08 09:36 AM

24 fps, blue ray and my telly.
 
In article en.co.uk,
Roderick Stewart wrote:

In article , Roger Wilmut
wrote:
The 25fps solution is the least worst. Apart from the occasional person
with perfect pitch, the 4% (2/3 semitone) increase is barely
detectable. Oddly enough, a 4% drop (as with made for British TV films
shown in a cinema) is much more noticeable, producing a distinctly
sluggish sound.


Is there some technical reason why they can't show 25fps films in cinemas
at the right speed? Cameras can do several speeds quite easily just by
changing a crystal.

Rod.


I'm not a projectionist, but I should imagine that most cinemas would
never have any reason to show films at other than 24fps and that the
option would not be built into the projector. The National Film
Theatre, which regularly show silent films, can run the projectors
slower, though I don't know how this is regulated; but it's quite
likely that they can't speed them up. However I don't know for sure.


All times are GMT +1. The time now is 04:11 PM.

Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
HomeCinemaBanter.com