Comments on: Standard data resolutions

By: Mark

Mark — Mon, 28 Aug 2006 19:38:29 +0000

Standard def DV-NTSC is 720×480, not720×486 (that, I believe, is digibeta. Thanks for the HD info, it was very helpful in trying to troubleshoot a downconversion issue I had today.

By: Jack

Jack — Wed, 22 Mar 2006 18:27:09 +0000

An interesting point. The aspect ratios quoted are the effective image aspect ratio
I’ll quote the BBC on this:

Digital pictures are effectively wider than analogue pictures by 18 pixels but the 4:3 image sits inside the 720 by 576 area. The additional 18 pixels are required for digital processing and it would be perfectly acceptable to leave them black – but if the image is shrunk via a digital DVE, two 9 pixel wide black stripes will be seen at the sides.

This means, in practice, 720×576 (or 2048×1556) have an assumed mask of several pixels on the horizontal. The values presented in the table above are industry standards. If you use them, you won’t go wrong (unless you use a pseudo-digital DVE). Someone else may be able to correct me on this, but I believe that systems such as Fire compensate internally for this discrepancy.
Thanks for the link by the way.

By: Zoltan

Zoltan — Wed, 22 Mar 2006 18:05:56 +0000

Hello!
A question: How can be the pixel aspect 1:1 and the image 1:1.33333 with the resolution 2048 by 1556. Either pixel is not square or image has 1:1.3162 aspect. An other thing for PAL: The true 4:3 contains only 702×576 pixel, and the pixel aspect is 1.094. The 720×576 image has 1.367521 aspect. See: http://www.uwasa.fi/~f76998/video/conversion/

By: Jack

Jack — Thu, 23 Feb 2006 18:06:40 +0000

David, I’ve corrected the Super 16mm entry. The C-Scope values assumed a digital squeeze. I’ve added separate values for the resolutions of images with a pixel aspect ratio of 1.0

By: Jack

Jack — Thu, 23 Feb 2006 17:55:59 +0000

Mike, thanks for the additions. I’ve corrected the table

By: Mike Jennings

Mike Jennings — Sat, 18 Feb 2006 00:01:57 +0000

1440×1080, PAR 1.33 is also the dimension for Sony and Canon’s 1080i HDV formats.

DVCPRO HD is 1440×1080 at 50i, but actually 1280×1080 at 59.94i. Its 720p60 resolution is 960×720.

–Mike Jennings
–Adobe Systems

By: David

David — Fri, 17 Feb 2006 23:25:20 +0000

The resolution for Super 16 should be 2048×1240 and is a 1.65:1 aspect ratio.

2.35:1 = 2048×871 (most people round it to 872), 1828×778, 3656×1556

Keep in mind that 2.35 is not what you have on your negative. The scope image is actually 1.174:1 aspect ratio usually 1828×1556.

By: Jack

Jack — Sun, 30 Oct 2005 12:01:01 +0000

Yes, that is correct. I will also include the square pixel dimensions to avoid further confusion.

By: Robert Lund

Robert Lund — Thu, 27 Oct 2005 21:52:58 +0000

Thanks for indicating a distinction. However, there is still a discrepancy.

Look at PAL – image size is 768×576 for square-pixels (pixel aspect ratio = 1); PAL DV image size is 720×576 (fewer samples/line, wider pixels, pixel aspect ratio = 1.067 = 768/720).

NTSC image size for square pixels is 648×486 (not shown!?); NTSC has MORE pixels/line, 720×486, so pixels are narrower than their height – so pixel aspect ratio is 648/720 = 0.9.

By: Jack

Jack — Thu, 27 Oct 2005 15:50:32 +0000

Xavier, sorry about the confusing overlapping terminology. SD does mean Standard Definition. The title refers to the typical pixel resolutions for different formats, which in turn encompasses Standard Definition (video). Hope this clears things up.