Re: Advice for compressing TIFFs

On 25 Apr 2006 20:31:46 -0700, "cubilcle281"
<cubicle281@xxxxxxxxxxxxxx> wrote:


1. Am I likely to achieve any saving with LZW compression on
16-bit-per-channel scans? Given that the LS-2000 only does 12-bits per
channel, I figure there should be a reasonable amount of dead space

2. Since many of the scans are done, is there a program available that
will do the conversion in 16-bit. Since PSE doesn't support 16-bit, I
haven't even tried that, and shelling out for the full photoshop for
this would be a waste.


The best compression schemes are image-dependent
in terms of *how much* compression you'll end up with.
This is true of LZW as it is with JPG.

Why not just try it and see? In general I find LZW
compression of images to be hardly worth the trouble.

Here's what I just got from Photoshop:

TIF: 402.8 MB (4000 dpi, 16/48bit scan of 645 MF film)
LZW compressed TIF, same file: 331.8 MB

As for compressing 16-bit TIFs after the fact, there's
nothing to stop you from ZIPing them. Ie., WinZip
also implements LZW, as I recall -- and does so on
arbitrary file formats and sizes.


rafe b
www.terrapinphoto.com
.

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