Canon XLH1 does uncompressed 1080i 4:2:2 over HD-SDI

[Stephen L. Noe]

Originally Posted by Steven White

What's cute is that the price point for this new machine is similar to a fully loaded HVX. I honestly wonder how many people who set budget asside for an HVX machine would consider switching.
-Steve

Count me on that list. We are already completely setup for HDV.

[Thomas Smet]

THE HVX200 does have the advantage to easy 4:2:2 recording for bluescreen shots. Of course most bluescreen work is done in a studio environment so the SDI from the XLH1 would actually be of higher quality since it is uncompressed. While the HVX200 should also be able to do uncompressed HD video it would only be able to do this via analog component outputs. The XLH1 keeps it all digital for a very clean 4:2:2 signal.

The HVX200 still has the advantage of less compression on the run however. No matter how good of a camera the XLH1 is it still uses a 1080i form of HDV with very high compression.

[A. J. deLange]

Yes, but how much less compression. Are 1.4 Gbps out the SDI port and 25 Mbps HDDV the only options? Or is DVCPRO HD at 100 Mbps also available (tape and or SDI)?

[Edwin Hernandez]

Is the HD SDI or the SD SDI output usable or worth using after the tape has been recorded and the signal has been compressed into the 25Mbps HDV ?

Will it retain the 4:2:2 out of HDV through SDI?

Is it exclusively to be used connected to an HDCAM SR deck or BETACAM deck while recording?

[A. J. deLange]

No! Once it has been recorded as DV it has been downsampled to 4:1:1 (SD and HD). Furthermore, the HD has been run through MPEG temporal compression. MPEG temporal compression results in a lovely HD picture until something moves. That's why my enthusiasm is dampened. If my only options are HDDV and 1.4 Gbit SDI which I can't practically capture I'm not so enthusiastic. I like to shoot in the woods - not in a studio.

[Greg Boston]

Originally Posted by A. J. deLange

No! Once it has been recorded as DV it has been downsampled to 4:1:1 (SD and HD). Furthermore, the HD has been run through MPEG temporal compression. MPEG temporal compression results in a lovely HD picture until something moves. That's why my enthusiasm is dampened. If my only options are HDDV and 1.4 Gbit SDI which I can't practically capture I'm not so enthusiastic. I like to shoot in the woods - not in a studio.

Just a clarification. SD is 4:1:1 and HDV is 4:2:0. But yes, once it's on tape, you've already thrown out most of the image. Having the SDI output allows capturing to anything (deck, or pc) that can do SDI. I wouldn't be surprised to see a mountable hard disk solution in the future that can accept HD-SDI. The drives can be made small enough now, that it could have a raid array perched on the rear bracket. Since Firestore has products forthcoming for the JVC and Panasonic cameras, it stands to reason that they may have a solution in the works for the Canon camera as well.

-gb-

[Mike Marriage]

Originally Posted by Greg Boston

I wouldn't be surprised to see a mountable hard disk solution in the future that can accept HD-SDI. The drives can be made small enough now, that it could have a raid array perched on the rear bracket. Since Firestore has products forthcoming for the JVC and Panasonic cameras, it stands to reason that they may have a solution in the works for the Canon camera as well.

-gb-

Do you mean to capture uncompressed HD!!! At 1.5Gb/s! That would take a serious RAID array, especially with 2.5" drives. That is about 35 times faster that the fastest current Firestore!

If the output was compressed to say a 50Mb/s codec first, that would work.

[Steven White]

Do you mean to capture uncompressed HD!!! At 1.5Gb/s! That would take a serious RAID array, especially with 2.5" drives. That is about 35 times faster that the fastest current Firestore!

You're getting ahead of yourselves. Not even the Hollywood folks with F950s capture truly uncompressed HD from their Dual Link SDI connectors... They run them into a Sony HDCAM SR deck which merrily compresses the data by about 2:1 before storing it.

Compressing a real-time HD stream isn't as hard as you'd think - the CPUs and RAM are fast enough - you just have to pick a reasonable compromise in terms of a codec to go to... and there are some really promising candidates out there.

-Steve

[Mike Marriage]

Originally Posted by Steven White

You're getting ahead of yourselves. Not even the Hollywood folks with F950s capture truly uncompressed HD from their Dual Link SDI connectors... They run them into a Sony HDCAM SR deck which merrily compresses the data by about 2:1 before storing it.

Compressing a real-time HD stream isn't as hard as you'd think - the CPUs and RAM are fast enough - you just have to pick a reasonable compromise in terms of a codec to go to... and there are some really promising candidates out there.

-Steve

That is exactly the point I was making Steven - no one is going to be capturing uncompressed HD. Personally I would have built a higher bitrate (higher than HDV) encoder and drive controller into the camera.

[Steven White]

Personally I would have built a higher bitrate (higher than HDV) encoder and drive controller into the camera

Well - that would significantly add to the cost, and the XL H1 would suffer the same crticism of the P2 option on the HVX200. It would also decrease battery life...

Basically you're asking for the equivalent hardware of a BlackMagic card, a high end CPU and RAM, and a dedicated hard drive... and that option is available to you - for the price of a couple P2 cards.

-Steve

[Mike Marriage]

Originally Posted by Steven White

Well - that would significantly add to the cost, and the XL H1 would suffer the same crticism of the P2 option on the HVX200. It would also decrease battery life...

-Steve

The effect on battery life would be less than recording to HDV as there are no moving parts required. I would think that the exsisting chip could easily cope with a higher bitrate interframe codec. It is not like P2, because it could output via firewire or USB2 straight to a standard hard drive - the controller would already be built into the camera. I agree that the controller would cost a few $$$, but not a huge amount. If an HVX can dump to a hard disk, it isn't hard to extend that to direct capture. It may require specially formatted drives. You could mount a 2.5" drive on the rear of the camera if you needed. Then as solid state prices drop, you start using that instead.

Originally Posted by Steven White

Basically you're asking for the equivalent hardware of a BlackMagic card, a high end CPU and RAM, and a dedicated hard drive... and that option is available to you - for the price of a couple P2 cards.

-Steve

No Blackmagic card - the signal is compressed straight from the DSP, like with HDV. The CPU is already there and the hard drive/solid state you buy separately.

Yes it is just like P2 - a non-linear storage method, but would be cheaper and is more "present" proof.

[A. J. deLange]

I forgot to mention that both SD and HD undergo spatial compression (DCT) before being written to tape. This is lossy.

I agree that something like DVCPRO HD @ 100 mbps would have made this camera the cat's meow though you'd only get 15 min on a casette (unless they allowed it to take the next size up -SWAP and $ problems there) and if they have to license this from Sony (?) that would be more $ still.

[Jacques Mersereau]

Well, well, well, so Canon actually did what I have been whining for!
An HDSDI output on this new camera. COOL!
The thing is I really wanted either 720P SDI (SMPTE 292) or 1080P@24 FPS.
That said, HDSDI output is really a huge step forward in bringing a
professional feature to a prosumer camera.. Now we can hook up to
all kinds of decks and interfaces. Things are getting VERY interesting!!!

I have lots of questions:

1) Will Canon will be able to offer 720P or 1080P@24 FPS in the near future? (Progressive minds will want to know if those HD flavors might be a firmware update in the next few months?)

2)Can this camera output standard def. SDI now?

3) Does anyone know if this camera uses 1/3" chips?

4) What's the chip set pixel count?

5) Can one use the old XL EOS adapter and Canon 35mm glass?

[Mike Marriage]

Originally Posted by Jacques Mersereau

Well, well, well, so Canon actually did what I have been whining for!
An HDSDI output on this new camera. COOL!
The thing is I really wanted either 720P SDI (SMPTE 296) or 1080P@24 FPS.
That said, HDSDI output is really a huge step forward in bringing a
professional feature to a prosumer camera.. Now we can hook up to
all kinds of decks and interfaces. Things are getting VERY interesting!!!

I have lots of questions:

1) Will Canon will be able to offer 720P or 1080P@24 FPS in the near future? (Progressive minds will want to know if those HD flavors might be a firmware update in the next few months?)

2)Can this camera output standard def. SDI now?

3) Does anyone know if this camera uses 1/3" chips?

4) What's the chip set pixel count?

5) Can one use the old XL EOS adapter and Canon 35mm glass?

1) I think until it is proved otherwise, we should presume that 24f = 24p, so in that respect it already has it. That is what is being claimed, only tests will tell.

2) Yes

3) 3 x 1/3" CCDs

4) 1440x1080 effective

5) I believe so.

[Jean-Philippe Archibald]

Jacques, I think that your question 2 to 5 are already answered on the XLH1 watchdog's page.

http://www.dvinfo.net/canonxlh1/xlh1skinny.php

The CCD block in the XL H1 utilizes three one-third inch 1.67 megapixel CCD image sensors which provide an effective target area of 1440 x 1080 pixels.

The earlier EF adapter for the Canon XL series is of course fully compatible with the XL H1, and most of the Canon EOS line of 35mm still photography lenses may be used for HD, the caveat being a 7.2x multiplication factor which renders most all EOS lenses to an extreme telephoto field of view.