p.1 #1 · An observation on TIFF compression in CS6 and LR4
Can some one please explain this observation to me:
I took a flattened TIFF 16 image in CS6 and saved it with ZIP compression on my Mac computer.
I took the identical TIFF 16 image in LR4 and saved it with ZIP compression.
The results are as follows:
Size of original TIFF file: 83.1 MB
Size of TIFF saved with CS6 ZIP: 80.7 MB
Size of the same TIFF saved with LR4 ZIP: 69.7 MB
It's as if the LR4 version of ZIP compression works better than the CS6 version. Is this possible? I can't find any info on the internet to help me with this.
p.1 #3 · An observation on TIFF compression in CS6 and LR4
Must be one of those 'Mac things.'
Actually, there are many different ways to apply the basic Zip compression technique. (Technically, Zip is a different and somewhat more efficient compression scheme than the 'LZW' scheme used in a Tiff.) Whenever compressing, the computer has a window of data in which it tries to find duplicate data. Besides using different routines, different compression programs/implementations usually offer varying/user defined window (also called dictionary) sizes. I think most graphics formats, such as Tiff, Gif, etc., only looks at one row of pixels at a time, whereas a general purpose Zip program may have a window of many megabytes. The larger the window, and the more sophisticated the compression scheme, the greater the potential compression.
p.1 #5 · An observation on TIFF compression in CS6 and LR4
I do not use Tiff Compression. I was just researching it to see how much it would compress my files in case I wanted to change the way I save my photos. Obviously, LR4 does a better job at compression. I have about 10 Terabytes of photos, and was just considering a way to possibly save some room. But have not made any decisions. Everything is currently backed up to 3 separate systems (hard drives, RAID, Time Machine, etc.)
p.1 #7 · An observation on TIFF compression in CS6 and LR4
It's not to exclude that Photoshop saves information in a different way than LR because of the header of the file.
This happens usually between different software and changes the ratio of the compression quite a bit.
