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Compressing .tif

Posted: Thu Mar 28, 2019 5:50 pm
by matti
I have scanned several hundred old photos as 600ppi 48bit color .tif files with Canon CanoScan LiDE 220. I added EXIF dates and IPTC Captions and Keywords with GC, exported as .jpg via Lightroom and added more metadata with GC. I now noticed that the .tif files are uncompressed and I'd like to compress them before archiving them to save space. This is going to take some time on my Late 2009 Mac mini so I'd like to get it right. There are 30 GB of files and I guess they might compress to about 15 GB or maybe even more.

Are these GC settings good for future-proof storage:

Compression: ZIP. This is not the default but I want the best compression.

Format: Little Endian (Intel).

Photometric Interpretation: White is Zero. (The manual says Black is Zero is standard on PCs, though?).

File Kind: Single Page File (or Same as Original -- I don't have any multi page files.)

Stripe Stream OFF.

Alpha Channel: Non Premultiplied. Correct? The manual does not explain this.

Embed Metadata (if available): I guess in my case I only need "Exif" and "IPTC" and maybe "ICC" but I guess it doesn't make any difference to check all of them except "Exif:Description to File Name" because I want the file names preserved.

Re: Compressing .tif

Posted: Thu Mar 28, 2019 8:52 pm
by forum_adm
Yes, you can just use the ZIP compression.

A scanned image has no alpha channel. So, that setting doesn't matter.

The other items should work that way.