On Dec 6, 2005, at 9:22 PM, Shel Belinkoff wrote:
But it's not a 43mb TIFF - it's a 6.5mb JPEG. How does a small
JPEG turn
into a larger TIFF file containing more information?
When decompressed, the 6.5Mb JPEG with the stated pixel dimensions
would turn into 43Mb of data in memory. That's all I was saying, as
I was afraid you may have misread the original post as being a 6.5Mb
TIFF :)
The amount of information contained in a JPEG file doesn't really
depend on the size of the JPEG file itself as it depends a lot on the
amount of detail present in the image. JPEG compression does throw
away a lot of data, which isn't necessarily the same as throwing away
a lot of information. I'll qualify that as saying that JPEG should
only be used as an output format rather than storage/archiving/editing.
Looking at the typical compression ratios I've been getting with my
web pics, a 43Mb TIFF reduced to 6.5Mb JPEG would be pretty good.
Hopefully the printers didn't try making major adjustments to the
JPEG...
- Dave
