View Full Version : Why no 720/60 on 1080 cams?


Steve Phillipps
May 18th, 2008, 02:31 AM
Why do Sony and Panasonic still seem intent on handicapping some of their cameras (actually I know the reason). For instance, the HPX3000 looks great, full raster 1920x1080, but sometimes (and often if you shoot sport or wildlife) you need slomo, so why don't they have a 720/60P option? It can be done because it is done (Sony EX1 and others), the data rates add up surely 'cos you've got 2x temporal and 1/2 spatial resolution. Same with Varicam 3700. Same with Sony 750/900, why don't they have a 720/60P mode? The new PDW700 has both, BUT only 50 mb/sec!
Why can't they just make good camera that covers all the bases? This is not a cost issue, and it can be easily implemented, they're just trying to fleece more money out of people, and not giving us a camera that we want.
Steve

Brian Drysdale
May 18th, 2008, 03:09 AM
The reason for the Sony HDW750 and F900 not having the 720p is that they use traditional video recording, so there would be greater additional costs having 1080p to 720p in camera, compared to the lower cost computer power available today which allows that option in camera. The F900 does cover all the standard frame rates compared to the cheaper more broadcast centred HDW750.

However, if you have 1080p available in camera, I don't know why you'd actually want to shoot 720p. The Varicam, of the same time frame, has the big advantage of the variable frame rate as it's big selling point. The other good factor it had was it had was more a camera issue, the film rec option, which was popular for grading in post and its "look".

I don't think you can compare older designs, which were pushing the boundaries at the time of their design, to modern designs with IT elements that allow changes to formats just by using their firmware and recording the output onto a memory card

Steve Phillipps
May 18th, 2008, 03:14 AM
Brian, if you could do 50 or 60fps in 1080 then I agree, why would you want to shoot 720, but you can't. For flying birds etc. I'd rather have 720/60 than 1080/30 any day, there's just no contest. The PDW700 is going to have the option, but lesser data rate.
Steve

David Heath
May 18th, 2008, 03:23 AM
However, if you have 1080p available in camera, I don't know why you'd actually want to shoot 720p.
Currently technology (except at the very high end) only permits 1080p at the lower frame rates (24,25,30) - no 50 or 60 that is needed for "smooth motion". Hence if you want the latter, you either have to go for interlace, or 720p50/60.

Steve - you say "only 50Mbs" in relation to the PDW700, but inter frame 50Mbs should be at least as good as intra frame 100Mbs in terms of quality - if needing more processing to edit. The BBCs acquisition guidelines have been recently linked to on this board and they state minimums of 100Mbs intra, 50Mbs inter as acquisition codecs for unrestricted use. My hunch is that the PDW700 will turn out to be a very successful camera.......

Steve Phillipps
May 18th, 2008, 03:50 AM
Yes David, agreed. Seems to be a lot of feeling that the 50 mb/sec on the PDW 700 will looks great. The option of SxS adapter on it looks good too, and I think that if you can record to SxS and disc at same time then that'll be really interesting as you'll have solid state and archiving simultaneously.
Steve

Brian Drysdale
May 18th, 2008, 05:55 AM
Currently technology (except at the very high end) only permits 1080p at the lower frame rates (24,25,30) - no 50 or 60 that is needed for "smooth motion". Hence if you want the latter, you either have to go for interlace, or 720p50/60.



I was thinking more in terms of the main shooting format, rather than effects shots.

Ray Bell
May 18th, 2008, 06:51 AM
I'm sure there is a technical reason for lack of 1080 60P on these cams
but if you want 1080P then scale it in post...

Cineform does a great job of converting 720p to 1080p.. so you get great
slo mo...

Tim Polster
May 18th, 2008, 06:53 AM
This has puzzeled my as well.

The XDCAM HD 335/350 cameras don't have this when the two cameras from Panasonic that are its main competition have every format.

(I kow the 350 has 60 frames for effect, but at half the resolution)

This is a main reason why I have looked elsewhere when looking at a camera in this class.

IMHO, a big mis-step by Sony with these two cameras.

David Heath
May 18th, 2008, 07:55 AM
I was thinking more in terms of the main shooting format, rather than effects shots.
That was what I meant. The frame rates currently practical with 1080p suit "film-look" (or "juddery motion", depending on your point of view), but not the smooth motion that such as sport really demands. For that you need 50/60 images per second, and whilst 1080p/50 is really what would be liked, practically it has to be 1080i/25 or 720p/50.

Robert M Wright
May 18th, 2008, 08:15 AM
I'm hoping the upcoming Panasonic HMC150 turns out to be a decent camera (and at a good price). One of the compelling features (to me at least), is 720p60 recording. I love the fluid motion of 60p.

John Bosco Jr.
May 18th, 2008, 09:05 AM
I'm hoping the upcoming Panasonic HMC150 turns out to be a decent camera (and at a good price). One of the compelling features (to me at least), is 720p60 recording. I love the fluid motion of 60p.

I think mainly why 1080 60p is not an option (except in high-end HD cameras) is that Broadcast TV currently cannot handle the bandwidth. So manufacturer's figure that right now there's no need for 1080 60p. Once there is a codec that can efficiently get 1080 60p within the bandwidth of Broadcast TV, then I think you will see 1080 60p. But then what becomes of 1080i and 720p; they are no longer needed. What a concept? Only one high definition standard.

Brian Drysdale
May 18th, 2008, 09:06 AM
That was what I meant. The frame rates currently practical with 1080p suit "film-look" (or "juddery motion", depending on your point of view), but not the smooth motion that such as sport really demands. For that you need 50/60 images per second, and whilst 1080p/50 is really what would be liked, practically it has to be 1080i/25 or 720p/50.

Yes, sports transmissions are different, unless they want a stylised look. Soaps, being traditionally interlace on SD, may also go that route, as will many other general TV programmes, plus the news.

Glenn Chan
May 19th, 2008, 08:16 AM
But then what becomes of 1080i and 720p; they are no longer needed. What a concept? Only one high definition standard.

As far as I know...
Terrestrial broadcasting will likely stay 1080i + 720p. To change all receivers (again) likely will not happen... at least for a few decades.

Cable (and other delivery methods) might move to 1080p50/60, but this will require a compatible set-top box.

My guess is that SD broadcasted digitally will stick around for some time (much like how AM is still around).

2- With AVC compression, 1080p50/60 may deliver slightly better quality at the same bitrates. (I've not seen this for myself.)

3- From a production standpoint, most facilities are wired for 1080i/720p. The higher bandwidth of 1080p60 requires 3gbps cabling.

It would also require VTRs that support that, and other infrastructure (e.g. routers).

David Heath
May 19th, 2008, 12:09 PM
As far as I know...
Terrestrial broadcasting will likely stay 1080i + 720p.
Maybe, but I think the real move is towards it as a production standard. Obviously it will downconvert well to both 1080i/25 and 720p/50, and remains the best possible quality in all respects for the future.

2- With AVC compression, 1080p50/60 may deliver slightly better quality at the same bitrates. (I've not seen this for myself.).
Not sure - what I have heard is that the compressed for transmission quality is a lot less than twice what's needed for 720p/1080i, contrary to what may be expected.
3- From a production standpoint, most facilities are wired for 1080i/720p. The higher bandwidth of 1080p60 requires 3gbps cabling.
Yes, but it can work with doubling up, using two standard cables to carry it. (When each carries an independent, but mirror image 1080i version. Lose either cable and you still have a complete 1080i signal.) Conceivably, the HD-SDI spec could be extended to allow for 2:1 compression, to get 1080p/50 down a single, standard cable?

Glenn Chan
May 19th, 2008, 01:10 PM
With AVC compression, 1080p50/60 may deliver slightly better quality at the same bitrates.
Ack! What I meant to say is that it delivers slightly better quality at the same bitrates compared to 1080i. So there wouldn't be any reason to use 1080i.

2- The dual link approach would be unwieldy since it would double the amount of cabling. Some of the cable trunks are thick enough already... double that would get difficult to manage.

As for compression, I think the concerns were quality and complexity. (Or something like that.)

I think now everyone has decided on 3gbps over a single wire.

Casey Krugman
May 22nd, 2008, 08:38 AM
I hate to be the cynic here guys, but these companies dont want to make the perfect camera. Frankly, it's bad for business! Think about it, if the companies made a camera that did everything, than everybody would not buy a camera in the future until the resolution changed.
Call me paranoid, but why would any of these companies want to build a "perfect" camera?

Glenn Chan
May 22nd, 2008, 10:14 AM
But right now we can't make the perfect camera...

There are companies like Red who are pushing the performance/price envelope.... but even they aren't making the "perfect" camera.

David Heath
May 22nd, 2008, 12:47 PM
Call me paranoid, but why would any of these companies want to build a "perfect" camera?
Worry that if they didn't do it, somebody else would? In practice, price also comes into the equation - no good building a "perfect camera" if nobody could afford it. Hence all design results in compromise to one extent, and the lower the price, the bigger the compromises have to be. Good design normally means not compromising one aspect far greater than any other - no point in having the "perfect" recording system married to a poor front end, and vice versa.

Steve Phillipps
May 22nd, 2008, 02:38 PM
I'm pretty much with Casey on this one!
Steve

Tim Polster
May 22nd, 2008, 03:48 PM
I perfect example is the Sony PDW-700. It shoots 25p, 30p, 50p & 60p, but it does not shoot 24p.

Now I don't engineer these things, but if it can shoot 25p, how much more engineering needs to happen to offer 24p on a $30,000 camera?

I have been wrong before.

I have seen a post or two about the addition of 24p to this camera though.

Brian Drysdale
May 22nd, 2008, 04:43 PM
I perfect example is the Sony PDW-700. It shoots 25p, 30p, 50p & 60p, but it does not shoot 24p.

Now I don't engineer these things, but if it can shoot 25p, how much more engineering needs to happen to offer 24p on a $30,000 camera?

I have been wrong before.

I have seen a post or two about the addition of 24p to this camera though.

Hmm... according to Sony "XDCAM HD products can record video signals in 1080/59.94i, 50i, 29.97P, 25P and native 23.98P"

Of course, this is a XDCAM HD 4.2.2 camera and they might feel there could be some stepping on toes with the F900R

John Bosco Jr.
May 23rd, 2008, 10:24 PM
But right now we can't make the perfect camera...

There are companies like Red who are pushing the performance/price envelope.... but even they aren't making the "perfect" camera.

What is the perfect camera? What is perfect for me may not be perfect for you or the next guy.

As far as the other comment on companies don't want to make the perfect camera... I Think that has some merit. Companies want repeat customers; that's how they make money.

On the subject of 1080p 60... 1080p HD displays are already out. The technology could possibly make it a reality for Broadcast television. However, with all the money invested in HD, I don't think broadcasters are in a hurry to change.

Finally, on the subject of digital SD, I think when digital HD hits the airwaves and replaces analog, I see SD fading fast. It will survive a few years in smaller markets and non-peak times, but I think when the public gets acustomed to the high definition signal, SD will be out like black and white TVs went out when color tv hit the scene.