Pixel width/height of 16:9 image on XL2
 

Hi,

I am shooting a wedding this coming weekend and I want to shoot it in 16:9 with my XL2 (PAL). I would like to know the actual width/height of the footage in pixels produced. This is so I can produce correct sized titles in Photoshop once it comes to editing.

Thanks

Chris Day
Perth, Western Australia

See my article "Canon XL2 CCD Block Overview," it should have the info you need. Graphics on that page are for the NTSC version, but PAL specs are up there as well. Nice to see another member from WA! We have a few of you sandgropers lurking about here and there.

Thanks Chris,

My query goes further though.

I am using a Canopus DV Storm with Premiere 6.5 and the 16:9 Canopus DV preset for widescreen is 1024 x 576 but if the CCD block for PAL is 960 x 576 does this mean that when I am setting up a new project in Premiere 6.5 for widescreen I should customise my project settings to a width of 960 pixels or just go with the Canopus setting. I know it is only a question of 64 pixels in the width setting but I do not want a skewed image for my client.

Thanks

Chris Day
Perth, Western Australia

If the preset is 1024 x 576 then create your pictures in that
resolution as well! Otherwise it might introduce all kind of aspect
and aliasing problems.

Unfortunately not all NLE makers use the same numbers to
calculate the actual resolutions, so stick with what your NLE
is using and you should be fine!

Thanks Rob for the feedback.

Chris Day
Perth, Western Australia

Chris, you're confusing pixels on the CCD with pixels on a display device. I don't use your software/hardware, so I can't tell you which setting to choose. But I can tell you that the XL-2, or any othe PAL video camera is only recording 720x576 pixels to tape. For 16:9 the camera shoots in anamorphic mode, which means that the pixels will be interpreted as being wider upon playback. In other words, the 16:9 image is squeezed horizontally when recorded such that everything will look too tall and skinny. When this video is viewed on a widescreen monitor it will be stretched horizontally so it's in the correct proportion again. 576x1024 is just the pixel dimensions of a PAL 16:9 image as displayed on a device with square pixels: 576 x 1.778 = 1024.

The following thread discusses the NTSC version, but the same principles should apply to PAL http://www.dvinfo.net/conf/showthrea...threadid=29087

The CCD block gets interpolated down within the camera. 720x480 (NTSC) and 720x576 (PAL) is what gets written to the tape regardless of the size/quality of the CCD block; the extra pixels used on the target area of the CCD ensure the best pixels are put on tape...allowing some headroom for optical image stabilization, pixel processing algorithms, etc.

For PAL widescreen, the signal recorded onto the tape should be 720x576 with a Pixel Aspect Ratio of 1.422. I believe what the Canopus card is doing when you capture is resampling that signal to 1024x576 square pixels:

720 x 1.422 = 1024

In the past I used Premiere 6.x with an old NTSC Canopus Raptor card and it did the same sort of thing with widescreen, so I think all will be well. But you really, really need to try it before you go on your shoot. Just shoot a 5-10 second test clip and run it all the way through your process: capture, insert a title, a still image, and export to your final output...DVD-R or whatever. It might take an hour or two, but better to know it'll work on wedding day than find out after the fact!

The Premiere manual, Help, and Adobe web site all have info on importing still images...I can't recall the details for Premiere 6.5 or Canopus since I'm now using PPro without a dedicated capture card.

Hope that answers your question...but if not, try, try again!

Cheers,

I have run into quirks using the canopus software. It seems to handle the 16x9 format differently. It actually flags the file as being a larger dimension when it really is 720x480 NTSC. I have been forced to capture using premiere to get around these limitations.