not happy with 1920x1080 p quality

jwfilm said:
How do I pan with a person always centered?
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Move the camera at exactly the same speed that the person is moving. That way they won't move relative to the screen.

But it is interesting to hear that I loose resolution (actually that should be detail though, since the the resolution is fixed by the cameras settings) at lower shutter speeds.
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If you shoot interlaced video at a shutter speed slower than the frame rate, the system has no choice but to drop one field (which cuts your potential resolution by up to half) because the system can only properly expose one field. The nature of an interlaced system demands that it finish processing one field before it can start processing the next, and since the field update rate is constant, if you hold the shutter open too long something has got to give when the next field's turn is due. So if you continue holding the shutter open and that next field comes up, and the shutter stays open, then that next field gets skipped and the previous (currently-being-exposed) field gets duplicated.
 
I guess that means that in 1080i/25p I can use a shutter speed of 1/25 without any loss...

I obviously misunderstood the previous panning instructions...well anyway, I havn't filmed interlaced so far and the replies to the original post of this thread seem to indicate that I was right in not doing so.
 
jwfilm said:
I guess that means that in 1080i/25p I can use a shutter speed of 1/25 without any loss...
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Correct. It will be blurrier than at 1/50th, but there won't be any field-dropping issues (like there would be if you tried to shoot 1080i/50i at 1/25).
 
DavidBeier said:
They joy of progressive scan. I still don't get why we bothered making 1080i TVs and cameras in the first place.
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The simple answer is motion rendition, when compared to 1080p/25, and because 1080p/50 is currently not generally technically viable.

The alternative answer is obviously 720p/50, which is generally considered comparable to 1080i/25 when motion rendition is important, for such as sport, and for such as a sports only network, that may indeed be a sensible option.

But for networks carrying a mixture of programming, and especially including films, the choice is far more complex. Such as films would then be shown 720p/25 - effectively severely limiting their resolution compared to 1080p/25. One solution would be to mix 720p/50 (sport) and 1080p/25 (drama) formats within a channel. In practice, a mix of 1080i/25 (sport) and 1080p/25 (drama) is seen as a better compromise, at least by the recent European start up HD networks such as Sky and the BBC. The transmission system is then always constant as 1080i/25, with the content either being true 1080i/25 or p/25 carried psf.

With display resolutions of 1920x1080 starting to become common, and likely to be the norm in a few years time, that's probably the best compromise - no scaling, except for SD and 720 signals.
 
Part of the issue is that the world is not all on the same page. If you did go progressive in the US (lots of things like the local news, etc. would look weird to most people) you would have to have a 24P and 30P option as 24P just flat out does not work for many broadcast applications. The problem with 30P is that you can pretty much only show that in NTSC. To my knowledge there is currently no way to convert 30P to PAL and not have it look like crap.



ash =o)
 
AshG said:
If you did go progressive in the US (lots of things like the local news, etc. would look weird to most people) you would have to have a 24P and 30P option ......
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For news and progressive scan, you would really need 60p in the US to avoid "looking weird", which currently means 720p. That's fine - it's generally accepted as comparable to 1080i/30.

But for film/drama etc, that is likely to be 24p, and here progressive 1080 (at 24Hz) is viable, and arguably far more desirable for the much better potential resolution offered by the 1080 frame.

Therefore, there is likely to be a need to mix 1080p/24 with either 1080i/30 or 720p/60 - possibly within a channel on a programme by programme basis. Whilst progressive scanning may indeed be seen as preferable to interlace in principle, interlace is increasingly being accepted as the lesser of the two evils when compared to broadcasting different frame sizes. (At least in Europe.)

A 1080p/24 and i/30 mix would never need scaling when 1920x1080 displays become the norm. A 1080p/24 and 720p/60 mix will mean some programmes will ALWAYS need to be scaled, whatever the resolution of the display. Roll on 1080p/50(60).
 
if the transmission of Hd content is through X amount Bandwidth, wouldnt just sticking to 720P (whether its 24P, 25P, 30P, 50P or 60P) be better in terms of compresson? i mean, if youre gonna compress, 1280X720 @ 24 30 25 50 60 Htz, should compress beter than 1080i 50/60 or 1080 30/50/60/24P? shouldnt it? assuming a broadcaster has the same bandwidth to use.
 
I dont think so. Yes, in the future it will be. But considering most stuff is 1080i and 1080i is only 20% more resolution, I would argue that unless you are totally fixated on resolution, 720 is a great picture. I would argue that 720p will be officially dead when we are shooting 1080p out of cameras in this price range. And if you say Red, I will hunt you down. :Drogar-Smoke(DBG):
 
TimurCivan said:
if the transmission of Hd content is through X amount Bandwidth, wouldnt just sticking to 720P (whether its 24P, 25P, 30P, 50P or 60P) be better in terms of compresson?
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I doubt that strongly, or at least doubt the overall effect will be better. Given a set bandwidth, (adequate for 720p/50(60)) then using 720p/25(24) for films, drama etc could indeed result in better compression/frame, but I suspect that overall the effect of more heavily compressed 1080p/25(24) frames would be better, owing to the higher resolution.
=Prodigy= said:
But considering most stuff is 1080i and 1080i is only 20% more resolution, I would argue that unless you are totally fixated on resolution, 720 is a great picture.
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Most sport and news type programming is indeed 1080i/25, but most film and drama for TV is 1080p/25 (carried psf) - certainly in Europe. Compared to 720p, 1080i is theoretically only slightly sharper vertically, but capable of 50% more horizontally, but 1080p (or psf) is capable of being 50% sharper vertically AND horizontally. If the camera front end is up to it.

But a critical element in all this is scaling the input to match the display resolution, and hence the comments by Yves Faroudja that Barry refers to. It's important to note that he did NOT criticise interlace per se, but rather expressed his opinions about SCALING progressive and interlace - "I can tell you the truth: interlace to progressive does not work!”. (See http://www.ebu.ch/en/technical/trev/trev_301-editorial.html if you want the source, full quote, etc.)

The importance of the distinction is due to full resolution (1920x1080) displays now becoming significant. Now scaling of 1080i is not required, and Yves Faroudja's comments are therefore not relevant here - a 1080i signal will simply be pixel mapped. Progressive may rightly be preferred to interlace - but not at any cost.
 
harddrive said:
It's important to note that he did NOT criticise interlace per se,
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I'm pretty sure that that's exactly what he did. The first sentence in that quote is "I am amazed that anybody would consider launching new services based on interlace. "

The entire editorial is pretty much a condemnation of interlace, explaining the EBU's position of why progressive is so preferable to interlace. ("Why is the EBU so firmly in favour of progressive scanning?" etc)

Interlace is horrible and should die, of that there is little confusion. But when will it die? Probably not until 1080 @ 50p/60p is in common use. Until that day is reached the EBU feels that Europe would be better off using progressive scan at 720p than using interlace at 1080i.
 
Okay, I'm confused and I would like a straight answer...can the HVX shoot 1080p or not?

I thought it only shot 1080 interlaced.
 
I know you can get 1080p but I thought the HVX did not shoot 'real' 1080p... I thought it was an equation it performed on 60i to get 30p..... Did I just speak blasphemy toward the HVX? I am a little confused... Sorry.

Gosh darn, Panny needs to hurry up and send me barry's book. I bet barry wrote it so all of us noobs would stop bothering him with questions.... haha
 
No, you've got it backwards. You're thinking of the Canon and Sony -- those use interlaced chips and then simulate 24p out of it.

The HVX uses progressive chips, it shoots genuine 1080p. It records it into an interlaced data stream (just like the DVX, SDX, SPX, XL2, DSR450WS, etc). But it's imaged progressive and you can strip out the pulldown in post to return it to its native progressive state.
 
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