nothing is broken. your scans are picking up more noise in the extra bits. there is much less run length correlation in the scan lines in a 16-bit image compared to an 8 bit image. this tells you how much random noise is present because of film grain and noise in the scanner. you should try the same scan in multipass mode (assuming your scanner supports it) to see if the files compress better or worse. try at least 8 passes. if your files then compress better, you have shown that your scanner has mostly noise in the least significant bits of the scanner A/D converter in 16-bit mode.
Herb... ----- Original Message ----- From: "Mark Cassino" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, February 12, 2004 2:37 PM Subject: OT: Compressing 16 bit TIFF's in Photoshop > I have scanner set up to save scans as 16 bit tiffs. The scan files are > just over 138 megs each. When I save them in Photoshop with LZW > compression enabled, they _grow_ to just under 164 megs. With 8 bit TIFFs, > the LZW compression does indeed compress, as opposed to inflate file size.
