2005.09.23 21:11 "[Tiff] Additional Lossless Compression Schemes", by Frank Warmerdam

2005.09.25 20:31 "Re: [Tiff] Additional Lossless Compression Schemes", by Bob Friesenhahn

On Sun, 25 Sep 2005 edward@sidefx.com wrote:

I'm not sure what Joris meant here by "large", I'd like to point out that more and more CG films are going to IMAX. According to one source (http://cat2.mit.edu/sagrada/cg.htm), the typical resolution here is 4K wide although the theoretical limit of IMAX is 8K.

If there is a theoretical limit for IMAX then I expect it is more like 21K when the broadest part of the image is considered (IMAX frames are rotated sideways on 70mm film). The NorthLight scanner is specified to scan IMAX at 8K. I am not sure if this means that the narrow (70mm) edge is scanned at 8K, or if this is the rotated resolution.

IMAX frames have 10X the area of 35mm frames. To put this in perspective, if a 10-bit 4K scan of a 35mm frame takes 50MB then a similar scan of an IMAX frame would take 500MB.

The largest 35mm film scan I have encountered is 16-bit and has the dimensions 5232x4376. This requires 131MB of disk space. 10X that is 1.31GB of disk space.

CG will naturally require much larger files than a film scan.


Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/