Tool for converting 12-bit TIFF images to 16-bit TIFF-images?

Hi,

I have some pictures taken by a CCD camera that are 12-bit TIFF
images. Photoshop (7.0) - even tough it opens them without an error
message - obviously cannot handle these properly as all images appear
totally black.
However, AFAIK Photoshop *can* handle 16-bit TIFF images, so what I
want to do is convert the 12-bit TIFF images to 16-bit TIFF images.
Conversion to 8-bit TIFF images is not an option because the images
are supposed to be used for quantitative evalutations (intensity
values) and I do not want to lose any information.

Hence, my question is: Which tool can convert 12-bit TIFF images to
16-bit TIFF images (or which tool allows opening 12-bit TIFF images
correctly and saving as 16-bit TIFF images)?

Peter

 

From: Peter Frank

Photoshop 7 can indeed open 12 bit tiff files (in 16 bit mode) ... there is
something else wrong.

10, 12, 14 and 16 bit/channel files are ALL saved in 16 bit format (ie, double
the size of 8 bit files but with zeros in the unused bits) and open in
Photoshop in 16 bit mode just fine. You do not need to "convert" these files
to 16 bits.

Dunno why they open "totally black" but it's not because they are 12
bits/channel ... I open 12 bit/channel files in Photoshop all the time from my
film scanner and from Canon digital cameras and they are fine.

 

Do the images open properly with IrfanView?
http://www.irfanview.com/main_start_engl.htm

 

Photoshop does the converting internally, there is soe other problem. Have
you tried opening them in some other program?

--
http://www.chapelhillnoir.com
home of The Camera-ist's Manifesto
The Improved Links Pages are at
http://www.chapelhillnoir.com/links/mlinks00.html
A sample chapter from "Haight-Ashbury" is at
http://www.chapelhillnoir.com/writ/hait/hatitl.html

 

Yes, they do. But I can only save them as 8-bit files, not as 16-bit
files.

Peter

 

Yes, I did. IrfanView and ThumbsPlus open and display them correctly.
Kodak Imaging for Windows doesn't.

Peter

 

It sounds like there has to be something non-standard in the tiffs that
some programs can read and others can't. Have you tried emailing Adobe with
the model number of your camera to see if it is a known incompatibility?
You might check with customer service for the camera company too.

--
http://www.chapelhillnoir.com
home of The Camera-ist's Manifesto
The Improved Links Pages are at
http://www.chapelhillnoir.com/links/mlinks00.html
A sample chapter from "Haight-Ashbury" is at
http://www.chapelhillnoir.com/writ/hait/hatitl.html

 

Another program that works quite well with 16 bit images is Picture Window
(including the "Pro" version). The author has stated something like "all
operations are internally 16-bit," but I don't specifically know if it will
open your 12 bit images. It is a full featured photographer's image editor,
and might be worth a try. I think that they have trial version(s), and the
total cost of the program is reasonable.

http://www.dl-c.com/Temp/

 

Problem solved. It was something I really could have thought of. For
some reason, the standard settings of contrast/brightness in Photoshop
were inappropriate for these images. By changing these settings, the
images became visible. I just didn't think of this in the first place
because IrfanView displayed them correctly without the need of any
manual adjustments. Anyway, everything is OK now.

Thanks to everyone for your help.

Peter

 

TIFF can store real, 12 bit/channel images (some scientific cameras use
this).
But Photoshop 7 (and CS) don't read that format.

Chris

 

Or sending Adobe a sample file so they can figure out what's going on?
(er, why do I talk about myself in the third person like this?)

Chris

 

That sounds like the data in the files is mis-scaled (old LEAF cameras
did that for a while).

Chris