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-   -   HDSDI OUT is 420 (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/130855-hdsdi-out-420-a.html)

George Strother September 17th, 2008 10:43 AM

Quote:

Originally Posted by Barry J. Anwender (Post 935125)
It would be helpful for and Engineer from Convergent to provide some factual confirmation one way 4:2:2/10-bit or the other 4:2:0/10-bit. Convergent is expending considerable resources to develop a product that is intended to make full us of the signal out of EX1/3 SDI port.

For my part, it's hard to believe that Convergent would be advertising SDI 4:2:2/10-bit potential, charge a good buck for this capability and then deliver something less.

Notice that the Convergent site shows the Nanoflash with three cameras. The product was not developed for the EX1/3.

If you can patch an old VHS camera to an HD-SDI port, the Nanoflash would faithfully record it in 4:2:2/10-bit HD. But the picture wouldn't look any better than the composite out from the old VHS camera.

It's the same as capturing a composite feed from a VHS recorder and dropping it on an uncompressed 4:2:2 HD timeline. It would be in a 4:2:2 format, but there would not be any more image data than what came over the original composite wire during capture.

Steven Thomas September 17th, 2008 11:29 AM

Thanks David,
Sorry, I belive the discussion a while back was not regarding 4:2:2, but 10bit.
Elton Barlow mentioned he sent you an SDI captured Sheer file a while back.

DVXuser.com -- The online community for filmmaking - View Single Post - Sony EX1 market plan: typical Sony

Barry J. Anwender September 17th, 2008 02:04 PM

Quote:

Originally Posted by George Strother (Post 937682)
Notice that the Convergent site shows the Nanoflash with three cameras. The product was not developed for the EX1/3.

If you can patch an old VHS camera to an HD-SDI port, the Nanoflash would faithfully record it in 4:2:2/10-bit HD. But the picture wouldn't look any better than the composite out from the old VHS camera.

George, not sure which convergent site you looking at to make your claims and analogies?

EX3 & nanoFlash spec sheet:
http://www.convergent-design.com/dow...20Brochure.pdf

EX1 & Flash XDR spec sheet:
http://www.convergent-design.com/dow...20Brochure.pdf

Convergent is using the HD-SDI digital port and if you've been following the DVinfo threads on the Flash and nanoFlash then you'd also be aware of the comments made by the Convergent Engineering/Marketing folks with regards to working with the EX1/3.

George Strother September 17th, 2008 03:55 PM

Quote:

Originally Posted by Barry J. Anwender (Post 938278)
George, not sure which convergent site you looking at to make your claims and analogies?

EX3 & nanoFlash spec sheet:
http://www.convergent-design.com/dow...20Brochure.pdf

EX1 & Flash XDR spec sheet:
http://www.convergent-design.com/dow...20Brochure.pdf

Convergent is using the HD-SDI digital port and if you've been following the DVinfo threads on the Flash and nanoFlash then you'd also be aware of the comments made by the Convergent Engineering/Marketing folks with regards to working with the EX1/3.

The sites you link to show the nanoFlash and the Flash XDR with multiple cameras. Clearly it is not an EX1/3 specific product.

Quote:

Convergent is expending considerable resources to develop a product that is intended to make full us of the signal out of EX1/3 SDI port.
The Flash products are just recorders, "generic" HD-SDI 4:2:2 capture devices. Any HD-SDI signal you connect to the recorder will be captured in 4:2:2 10-bit format. Convergent has no responsibility for the way Sony processes the signal inside of the camera before the HD-SDI port.

Quote:

For my part, it's hard to believe that Convergent would be advertising SDI 4:2:2/10-bit potential, charge a good buck for this capability and then deliver something less.
Convergent is not delivering something less. Claiming their device captures 4:2:2 10-bit does not mean all cameras output native 4:2:2 10-bit or that the EX1/3 does. If a signal starts as 4:1:1 or 4:2:0 and that camera outputs converted 4:2:2, Convergent devices will capture it as 4:2:2 10-bit.

Thomas Smet September 17th, 2008 04:33 PM

The thing I find the most amusing about all of this is that nobody can really seem to tell if what they have is 4:2:0 or 4:2:2 but yet they complain about how bad the 4:2:0 is. If it was really that bad then more of you would notice it.

Barry J. Anwender September 17th, 2008 05:23 PM

Quote:

Originally Posted by George Strother (Post 938607)
The sites you link to show the nanoFlash and the Flash XDR with multiple cameras. Clearly it is not an EX1/3 specific product.

So it follows that Convergent is a position of knowledge to confirm the precise nature of the HD-SDI signal coming out of the EX1/3. This is the point.

And if Convergent is not willing to confirm the facts for whatever reason, then from the posting above, Cineform has come forward to answer the question. If someone would kindly provide them an uncompressed file captured off the EX1/3 Hd-SDI port. Cheers!

Alex da Silva September 17th, 2008 05:26 PM

I agree to a certain level. If you can't really determine a difference by close analyses of the footage, the option is questionable.
But in other circumstances, for example color correcting, the 4:2:2 space will make a huge difference.
So, it;'s not just a question of "looks".

George Strother September 17th, 2008 06:08 PM

Quote:

Originally Posted by Barry J. Anwender (Post 938665)
So it follows that Convergent is a position of knowledge to confirm the precise nature of the HD-SDI signal coming out of the EX1/3. This is the point.

And if Convergent is not willing to confirm the facts for whatever reason, then from the posting above, Cineform has come forward to answer the question. If someone would kindly provide them an uncompressed file captured off the EX1/3 Hd-SDI port. Cheers!

I'm 40 minutes from CineForm. I sent an email to David this morning. Waiting to hear back.

James Huenergardt September 17th, 2008 09:51 PM

Hopefully George, you can help clear this up once and for all.

I'm really hoping that it is at least 4:2:2. A true 10-bit (non-padded) stream would be peachy too.

Mike Schell September 18th, 2008 02:02 AM

Quote:

Originally Posted by James Huenergardt (Post 938769)
Hopefully George, you can help clear this up once and for all.

I'm really hoping that it is at least 4:2:2. A true 10-bit (non-padded) stream would be peachy too.

I can absolutely confirm that the EX1/EX3 HD-SDI output has a full 10-bit resolution, not just 8-bit with the lower 2-bits forced to zeroes. We tested the output of the EX1/EX3 on our $25K Tektronix WFM-700 HD-SDI monitor. It is unquestionably 10-bit resolution. All HD-SDI sources are 10-bit 4:2:2, but often it's only 8-bit effective, with the lower 2-bits set to zero. The EX1/EX3 is a full 10-bits, which is really amazing given the price of this camera.

One of our local users can also confirm (through detailed image analysis) that the color sampling is indeed 4:2:2. We can not determine if the original sampling is 4:2:0 or 4:2:2 on our waveform monitor, since all HD-SDI is 4:2:2, but the original signal could have been generated from a 4:2:0 source and then upsampled.

Just to be clear, Flash XDR and nanoFlash uses the Sony MPEG2 CODEC for compression/decompression. MPEG2 is, by definition, only 8-bit processing, but can be either 4:2:0 or 4:2:2. Also the compression allows either 1440x1080 or the full 1920x1080. On our Flash products, the MPEG2 compression uses the full 1920x1080 4:2:2 processing at bit rates of 50/100 Mbps Long-GOP or 100/160 Mbps I-Frame only. So, although the processing is only 8-bit, we do not suffer from horizontal subsampling artifacts (scaling 1920 -> 1440) or loss of color fidelity (4:2:2 -> 4:2:0).

We should be able to soon upload some of the gorgeous airplane footage we showed at IBC (in QT format). The footage included smoke, water and high-motion without any visible artifacts whatsoever. This 7th generation Sony MPEG2 CODEC is simply brilliant, especially at the 50/100 Mbps level.

Barry J. Anwender September 18th, 2008 02:59 AM

Thank you Mike, this is indeed the independent confirmation that goes a long way to clearing up doubts, misunderstandings and possible bad feelings.

I also appreciate your comment about the source signal that it may be up-sampled to generate 4:2:2 and that there is no way of knowing. Perhaps that is what the Sony engineer at the IBC was referring too. What is truly important is your independent confirmation that the signal is genuine 10-bit and 4:2:2 color space.

Steven Thomas September 18th, 2008 08:18 AM

Mike, thanks for clearing these questions up.

Alex Raskin September 18th, 2008 08:18 AM

Here's the practical greenscreen test.

EX1 recorded to SxS card and out HD-SDI to Blackmagic Decklink Extreme simultaneously.

(Exposure: image was underexposed at acquisition with intention to manipulate it in post.)

SxS footage was later converted by HDlink from MP4 to Cineform Prospect HD High.

HD-SDI capture was live via HDlink to Cineform Prospect HD High.

(All software is PC based.)

Then both videos were placed into After Effects project, and same frame was exported as Photoshop files. I then exported from Photoshop to TIFF for more universal compatibility.

See files below (I hope they'll post here fine. If not, see my own web site below. Each image is over 8Mb. Right-click to download.)

http://primehd.com/sxs-sdi

They are named sdi and sxs accordingly, and contain areas of both motion blur and sharp still image.

Let me know how do you interpret the results.

My own humble interpretation is that there's no discernible difference in levels (including individual channels) or visible quality of the image. At 200x magnification, you can see very slight difference, with SxS image actually looking a tiny bit sharper. In any case, differences seem to be very close to noise level of the image.

Sadly, I have to conclude that, for all practical purposes, HD-SDI out of EX1 is the same as SxS in terms of visual quality and color space, which is 4:2:0.

There's a frame in my video (not posted here) with higher motion, where SDI footage looks a tiny bit better at 200x magnification, but that's it.

Bob Grant September 18th, 2008 08:24 AM

Perhaps what we should be talking about is chroma resolution rather than sampling.
If the chroma is being upsampled then little to nothing is gained by recording that signal over what can be done in post for where it matters e.g. keying.

Greg Boston September 18th, 2008 09:00 AM

Quote:

Originally Posted by Alex Raskin (Post 938979)
Sadly, I have to conclude that HD-SDI out of EX1 is the same as SxS in terms of color space, which is 4:2:0.

If true, then in my opinion it makes NO SENSE to put HDSDI on the camera in the first place. Why pay all the SMPTE licensing fees to provide an output that is essentially no better than what can be obtained by recording to the card?

These 4:2:0 optical block sampling claims also came about when the 330/350 were introduced. I've been told many times since then that if taken live, it's 4:2:2 sampling.

-gb-


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