TIFF file size Mac vs PC

pemmett

I recently worked with a company where one person worked on a Mac and the other on PC. The file size when saving the exact same file as a TIFF with exactly the same settings is about 5 times larger on the PC than on the Mac. Is there a reason for this? If I do the exact same export from Lightroom to a TIFF file format with the same settings then the file size is very similar. Any insights into this would be very welcome as this is really frustrating them. Thanks.

Richard

That sounds very strange to me. Same software, same file, same settings should give similar results. I'm skeptical that all the settings are the same. Compression? Alpha channels? Have you tried it yourself? You might try dropping them into something like Exiftool to compare the complete metadata from each. Dunno, but if you find the answer, be sure to post it.

pemmett

Richard, I've tested it myself and made sure all settings are the same, unless there is something in the preferences that I didn't find. I'll post if I get an answer. Not sure if anyone else has experienced this, but I know very few few groups that work on the same stuff and use different platforms like this.

ziggy53

A company I formerly worked for did have me process on both Mac and Windows, to satisfy 2 - different target vendors and clients. Most of the time the files would be saved as Photoshop PSD files, but sometimes a graphic artist or a customer required TIFF format files.

One time I was having some trouble with big TIFF files being output from the Mac and I used the PC to process the image, resulting in much smaller images; on the order of 5 - 7 times smaller.

It turned out that the Mac machine was outputting Uncompressed TIFF, while the PC was outputting Compressed TIFF. When I found the setting for the Mac it was in a different place than it was on the PC, making diagnosing and correcting the images' settings that much more difficult. Setting the Mac to produce compressed TIFF completely solved the problem in that case.

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Also look at the color bit depth. TIFF files can be either 8 - bit or 16 - bit per color channel. That could ostensibly produce a similar change in file size, depending upon the image content.

pemmett

Ziggy, You nailed it with the 16 bit depth vs 8 bit depth. The settings in Lightroom were different for editing the images in Photoshop - I can finally sleep :-)

ziggy53

Glad you got it solved.