As a long-time user of the TIFF format for somewhat unrelated purposes, I
feel most inclined to comment on this note:
Tiffs don't have any of the post-processing advantages of RAW
Which is obviously untrue, since TIFF (unlike JPEG) won't usually compress
data by throwing actual image data away, and also has the capability of
storing 12 bits-per-channel (well, actually, it will have to be be 0-padded
16-bit, but...)
Tiffs are a tricky subject, because they can have different
attributes like you say. I would be surprised if in-camera produced TIFFs
are 16 bits. They would be extra-huge if they were. Pentax's RAW files
basically *are* TIFFs (zero padded 12->16 for the -D, and packed 12->12
for the -DS). The difference is that only a single plane of 6megapixel,
12-bit data is necessary in RAW, but an interpolated version for R, G, and
B is needed for TIFF. Ignoring compression (as Pentax likes to do), a
16-bit linear RGB TIFF file would be 2 times as large as the 8-bit
gamma-correct TIFF, 3 times as large as the padded RAW, 4 times as large
as the packed RAW. If one didn't do white-balancing on the 16-bit linear
TIFF, the only thing RAW has as advantage would be the potential for a
more advanced Bayer interpolation.
Large tiffs may be an acceptable compromise. It's much bigger
than it needs to be, however, and does lose a slight bit of
flexibility.... not nearly so much as 8-bit gamma tiff or JPEG, though.
-Cory
--
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* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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