Off Topic: PhotoShop6 16 bit. PS6 16 bit tif.lzw rotate and save size growing problems, Tif.Zip crashes.
Off Topic: PhotoShop6 16 bit. PS6 16 bit tif.lzw rotate and save size growing problems, Tif.Zip crashes.
- Subject: Off Topic: PhotoShop6 16 bit. PS6 16 bit tif.lzw rotate and save size growing problems, Tif.Zip crashes.
- From: Brett Baunton Imagery <email@hidden>
- Date: Tue, 15 May 2001 10:06:12 -0700
Hello all,
I wrote this a while back and have been waiting for an official Adobe answer.
It never came so here goes. If I should post this to a photoshop list,
which one?
>
Thank you Chris for straightening out the cache histogram 5.5 vs 6 issue.
I always wondered why have that option that gives a false impression anyways.
Now I'm wondering about a couple of other options that don't work as
expected in PSv6 with 16 bit files. I've tried tech support with no luck. I
have just sent copies of the basic problem 16bit files to tech support via
email.
Problem: 16 bit files rotated via the canvas or the crop tool grow 20% or
more when saved as Tif with LZW compression! It appears to only affect an
arbitrary few degree rotation, not a full 90 or 180 rotation.
Maybe folks on this list could verify or shed more light on this one as I'm
sure we're all very excited about the new options available for editing
16bit files in v6. Here's our dilema, and the answer we get from tech
support is "why are you doing that with such a big file anyway?". The
problems cost us countless hours working on a 16bit raw drum scan that was
645 MB as 16bit just small enough to fit on a CD for archiving and
transport. Opening and resaving and resaving again, arrgh! As it turns out
we have the problem repeatable on much smaller 16bit files that we could
have been testing the issues on but we wer'nt aware of it to this noticable
extreme. I was asked to send off the 600+ MB file via email (They won't
accept a CD in the mail), however since we have discovered a problem with
smaller sized files we are sending off 100MB versions.
16bit.tif issues
NO CM, No Tags.
#1) RAW 16 bit file opened in PS6
Rotate image arbitrary on canvas or rotate during crop. Not possible in V4-5.
Save as tif no compression and it's slightly larger, original raw scan grew
just enough to not fit back on a 650 mb CD to 666MB.tif=NoLzw.
Is this because the PS6 version of tif is rewritten with more header info?
Save file as Tif-lzw compression and watch the file grow 20% or more.
You would assume after crop the image would get smaller and also LZW would
reduce even more. The version we rotated about 0.6 degrees grew to a
whopping 865MB! Tif.LZW No icon, No thumbnail. Smaller 100MB version grew
to 126MB.
#2) Nice but ugly feature the Tif.Zip. It compressed the file small enough
to fit on CD. Even with testing smaller files 16bit Tif.Zip it shrunk
however the file could not be opened even though it saved OK. PS 6 crashed
every time and corrupted the scratch disk so that no files were on the
scratch disk but available space was lost on the disk. Norton sees it, no
disk doctor error, can speed disk the data however you still have 0 files
on disk according to the finder and the only way to get the space back is
to ReFormat the scratch disk!
I know the scratch disk corruption was fixed in 6.01 updater. Why have the
option of Tif.zip? In fairness it says adobe says tif.zip not recommended
but you think it would work reopening the file in PS6. If it won't what's
the point??What is the image pyramid checkbox for? did'nt affect it either
way.
Adobe tech support says it does'nt happen to thier small test files.
Our files or larger 20MB + Photographic scans, sometimes in 16bit which
seems to be the LZW growing issue.
Can anyone confirm this?
Our system:
Mac G3 OS8.6 and G4's OS 9.0.4
256 RAM
Separate formatted Scratch disk assigned as primary scratch.
Sincerely, Brett Baunton
email@hidden