XL-H1 firewire out compression

[Tito Haggardt]

aloha
i know you can get 4:2:2 out SDI without sound with an XL-HI but what can you get out via firewire to hard disk and does it have sound. I am thinking its 4:1:1 with sound. but i'm just guessing.
thanks
tito

[Michael Galvan]

What comes out the FW port is exactly what gets recorded to tape. There is no quality difference. In HD modes, its 4:2:0.

In SD, its 4:1:1.

[Tito Haggardt]

thank you Michael
i take it there is sound embedded
tito

[Michael Galvan]

That is correct (along with timecode).

[Mark A. Sloan]

Having recently purchased an XL H1. I had a question regarding the compression of the footage. Please bear with me I don't know as much as I should but I am tring to learn.

The camera obviously shoots in full HD. When using a SDI output you can put it into the PC at full HD spec. When you record it onto tape it compresses the footage (via Mpeg2) does that mean the only way to get the uncompressed full quality is to capture it live using SDI?

If it records onto the tape as compressed, even if you play it back through the camera you will not get full quality because it has already been compressed right?

If I am understanding it correctly does that mean you only have 2 options really, capture live through SDI or capture to Firestore?

Thanks

Mark

[Michael Galvan]

The only way to get the pure uncompressed is through the HD-SDI port (which you then can capture uncompressed or to any compression scheme of your choice).

Once recorded to tape, its gone through the MPEG2 compression. Playing the tape back out through HD-SDI will only play it out, it's already been compressed.

Capturing to firestore is the same thing as to tape (compression wise) as the output through the firewire port is compressed already. Only through HD-SDI will you get a pristine uncompressed signal.

Hope that helps.

[Mark A. Sloan]

That is excellent thank you!

A tad misleading as you don't really get full HD recording unless it is live recorded. I can't image having to trapese a PC with me when trying to film little segments out and about.

Once you have put it to tape you still get a HD sized footage? but it is of less quaility but it seems that putting into premier pro 2 you can only get either DV sized footage or playing the tape back and getting compressed HD through an SDI connection?

[Michael Galvan]

Lets also understand here, the whole "Full HD" thing is really nothing but a marketing ploy. HDV may be subsampled from 1920 (1440x1080), but that doesn't mean it isn't HD. HDCAM is subsampled the same way and DVCPRO HD even further (1280x1080), but they are as full HD as they come.

I guess you more referring to a full raster format like HDCAM SR, where it is kept 1920.

[Mark A. Sloan]

Maybe what I mean is.

To get the best picture, uncompressed quality it can only be obtained from the camera by live streaming from the SDI port?

It is compressed onto a tape or downscaled through firewire the final quality will be lessened due to the compression?

[Michael Galvan]

Correct. The native format of the camera is the MPEG2 onto tape and through firewire.

It's HD-SDI port is the only way to tap into the pure video signal directly from the processing chip.

[Mark Job]

Originally Posted by Michael Galvan

Lets also understand here, the whole "Full HD" thing is really nothing but a marketing ploy. HDV may be subsampled from 1920 (1440x1080), but that doesn't mean it isn't HD. HDCAM is subsampled the same way and DVCPRO HD even further (1280x1080), but they are as full HD as they come.

I guess you more referring to a full raster format like HDCAM SR, where it is kept 1920.

.....Just to clarify and qualify...The Canon XL H1 outputs by Scaling Anamorphic pixels @ 1440 x 1080 to 1920 x 1080 out of its HD-SDI Uncompressed output. This is a perfectly good way of doing it. The HDCAM outputs a "scaled" 1920 x 1080 in the same way, only, I wasn't aware it was lower than 1440 x 1080 anamorphic pixels.