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-   -   50mbit/s for ex1/3 - like panasonics new cam? (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/147058-50mbit-s-ex1-3-like-panasonics-new-cam.html)

Thomas Diehl March 31st, 2009 03:13 AM

50mbit/s for ex1/3 - like panasonics new cam?
 
a lot of broadcasting stations want at least 50mbit/s (no matter what codec is used) and panasonics new camera AG-HPX301E even does 100mbit/s (4:2:2, 10bit) for a similar price as the ex3.
tempting. inspite of only 1/3inch chips. isn't it?
when will we see an update? nab?

Dean Sensui March 31st, 2009 03:41 AM

Have these stations properly evaluated the existing codecs and taken a close look at the quality of the images?

In the hundreds of hours I've shot, I haven't seen anything wrong with XDCam EX codec. Not just my opinion. The Discovery Channel thinks so, too and gave the format silver status.

I shoot green screen at 1080p30 with an EX1 on a routine basis and the composites are outstanding. Many who have seen them never realized it was a composite at all because it keys cleanly.

The 4:2:0 sampling also grades nicely. So anyone concerned over this codec failing when it comes to color sampling needs to see this format for themselves before passing judgement.

The codec holds up detail under very trying conditions, never falling apart even when there's a massive amount of changing detail.

I don't know how it works but it does. And the results are nothing short of remarkable.

So the people who are insisting on the higher bitrates are probably making assumptions and have not carefully evaluated what's out there.

Thomas Diehl March 31st, 2009 04:36 AM

so do you think convergent designs flash xdr does not make sense?
Convergent Design, experts in HDMI, SD, HD, and HDV

however, arte (german-french cultural channel) for example, clearly states 50mbit/s is required.
i can not force them to just look at the quality of the image ...

Ed Kukla March 31st, 2009 04:52 AM

discovery HD
 
So your local station doesn't think the EX cameras are good enough? Discovery HD will accept the EX cameras on par with the HDX900, Varicam & Sony F900.

Craig Seeman March 31st, 2009 08:38 AM

First of all "a lot of broadcasting want at least 50mbit/s" implies that there are a lot of people who are engineers who have little technical understanding.

Data rate, independent of codec, is near meaningless.

A lot of broadcasters accept XDCAM 35mbit/s and many use it for news. Others, like Discovery, which tends to have major rigorous standards, accepts the EX for programing.

Sorry, but a statement requiring a given data rate not attached to a specific codec is just plan stupid from a technical perspective. Any "body" making such requirement shouldn't be working in this industry in my not so humble opinion.

Quote:

Originally Posted by Thomas Diehl (Post 1036296)
a lot of broadcasting stations want at least 50mbit/s (no matter what codec is used) and panasonics new camera AG-HPX301E even does 100mbit/s (4:2:2, 10bit) for a similar price as the ex3.
tempting. inspite of only 1/3inch chips. isn't it?
when will we see an update? nab?


Jeremy Hugues March 31st, 2009 09:57 AM

only a firmware matter
 
Hi everyone,

From what I understand, Sony can do an update of our EX1 and 3 anytime. It only depends of competition and us, users, asking them to. The EX cam video heads are in 4.2.2. The SxS cards could easily handle a 50 mbits/s rate (which would be an argument to go for SxS instead of SDHC).
Our EX cams are just a big computer with excellent lenses and sensors. If we ask Sony they can bring very interesting changes. It is important to send them feedback. They do take them into account, at least the XD CAM EX responsible in Europe do.

Cheers

Craig Seeman March 31st, 2009 10:48 AM

Quote:

The EX cam video heads are in 4.2.2.
Video heads? What video heads?
It's an encoder chip and I've heard that it would require the chip to be replaced. Not firmware upgradable.

Quote:

Sony can do an update of our EX1 and 3 anytime.... Our EX cams are just a big computer with excellent lenses and sensors.
I don't think a firmware upgrade would give you computer a new CPU or GPU. New chip, new motherboard, new graphics card = new computer.

Brian Luce March 31st, 2009 11:30 AM

Quote:

Originally Posted by Craig Seeman (Post 1036856)
Video heads? What video heads?
It's an encoder chip and I've heard that it would require the chip to be replaced. Not firmware upgradable.


I don't think a firmware upgrade would give you computer a new CPU or GPU. New chip, new motherboard, new graphics card = new computer.

But wait, doesn't the nano flash record 422 out of the EX1? It's got to have 422 somewhere inside if it's recording that amount of color to flash.

Craig Seeman March 31st, 2009 11:58 AM

Not a video head though. Before the codec gets to it you have 10 bit 4:2:2 Uncompressed and that's sent out the HD-SDI to the Nano Flash.

The encoder chip in the camera though can't be changed by a firmware upgrade so I've heard by those who know the camera hardware.

In other words you either pick off the video pre encoder (as HD-SDI to Nano Flash does) or you replace the hardware encoder chip which probably isn't cost effective and may be an engineering issue.

Certainly Sony can bring 50mbit/s to EX (as they've done with HD on the 700) but it would likely be in a new camera.

Quote:

Originally Posted by Brian Luce (Post 1036922)
But wait, doesn't the nano flash record 422 out of the EX1? It's got to have 422 somewhere inside if it's recording that amount of color to flash.


Dean Sensui March 31st, 2009 12:02 PM

The EX1 can output 4:2:2 from the HD SDI port and the image is uncompressed at that point.

As everyone mentioned, the EX1 and EX3 provides a terrific image regardless of its data rate and 10-frame GOP compression. That's the first thing I tested when I rented the camera prior to purchasing one. I filled the frame with turbulent water falling into a pond and didn't see any sign of the codec breaking.

Thomas -- unless the broadcaster does an equipment inspection, how would it know what you shot your program on or what the original data rate might have been? Let's say you were editing with Final Cut Pro and then using Color for grading. The end result would be in ProRes format which is roughly 220 megabits/second.

As mentioned elsewhere on this board, if the content of the material is compelling enough, the technical requirements would most likely be waived. I'm certain that if you were the only one to get a shot of a tsunami wiping out New York and got it with a Flip Video camera, your station wouldn't decline the opportunity to use it.

James Huenergardt March 31st, 2009 12:07 PM

You won't get 4:2:2 from the EX1 or EX3 to SxS card in camera.

From my understanding, this is because there is only 1 'encoder' chip in the EX1/3's.

Convergent Design's 'encoder' uses 2 chips which gives you the 4:2:2 while just one chip gives you 4:2:0.

According to Convergent Design, I-Frame encoding at 100 Mbps is roughly equivalent to 35Mbps Long-GOP in overall quality.

Craig Seeman March 31st, 2009 12:18 PM

BTW getting back to the original post.
You can't compare data rates with different codecs by looking at the data rate itself.

XDCAM is a very efficient long GOP codec. That's why it'll look as good as some intra (non GOP) codecs at much higher data rates (DVCProHD for example).

AVCHD (also long GOP) is even more efficient than XDCAM but it takes a lot more computer power to decode.

XDCAM and AVCHD can look as good or better than DVCProHD and 1/3 to 1/4 the data rate.

AVC Intra (not long GOP) is less efficient than long GOP codecs but the codec is a very good. An AVC Intra file at the same data rate as DVCProHD file can be significantly better.

It's a bit more complex than what I'm stating but the short of it is it's technically absurd to claim a data rate alone as a specs sans taking the codec into account.

That's like saying a codec alone makes the picture better without taking into account the camera it's attached too.

Maybe AVCHD at 24mbps/s can look better than XDCAM EX at 35mbps/s BUT if the AVCHD is attached to a $500 consumer camera it ain't going to be near an EX3.

Certainly an EX 35mbps/s can be as good as or better than DVCProHD 100mbps/s and that can be the case with AVCHD 24mbps if the camera has a good "front end."

Again one can argue the finer points but for any broadcast facility to flatly say 50mbps/s as a base is technical ignorance in my opinion (I've been known to be strongly opinionated).

It can be as simple as comparing an EX1 to an HVX200 (and both are good cameras with reasons to like either) but in MANY WAYS the EX at 35mbps far exceeds the HVX200 at 100mbps in various chart tech tests (and live situations).

Gints Klimanis March 31st, 2009 12:56 PM

Quote:

Originally Posted by Thomas Diehl (Post 1036296)
a lot of broadcasting stations want at least 50mbit/s (no matter what codec is used)

DV50 is probably their minimum, but it's an intraframe codec. There is no way a 50 mbit codec, even for SD video, will compete with 35 mbps intraframe EX1 codec.

Thomas Diehl March 31st, 2009 12:59 PM

Has anybody been able to compare Flash XDR and/or avcintra-footage (AG-HPX301E?) with xdcam-ex footage side by side?

Alister Chapman March 31st, 2009 01:57 PM

Most of the broadcasters that are specifying a minimum of 50Mbps 4:2:2 are also specifying a minimum of 1/2 inch, full raster 1920x1080 sensors.

There is a very good reason for this and it's called diffraction. Cameras with small sensors suffer from diffraction issues at apertures less than f6. The severely limits the way lenses can be used.


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