TIFF files doubling in size

[Mike Pountney]

I have seen my saved TIFF files double in size recently to around 100MB even though I ensure I flatten all layers before saving - I use the LZ compression option too. It started in the version 22 and has continued in versions 23 and 24

Help!

[D Fosse · Accepted solution]

Are your files 8 or 16 bits? LZW compression doesn't work well with 16 bit data and will often just increase file sizes.

[Mike Pountney]

They are 16 bit - I sample my new files in Adobe Bridge first and select the images I want to work on in Photoshop.

The only thing that is different is the versions of Bridge and Photoshop have changed.

Thanks

[D Fosse]

Maybe your files used to be 8 bit and are now 16? That's a doubling of file size. I can't see what else could have changed. A pixel is still a pixel, and compression algorithms haven't changed that I know of.

In any case, as I said, if you have 16 bit files, don't use LZW compression. At best it's not effective, at worst file size goes up.

There was a bug, recently fixed, that applied (RLE) compression to PSD/PSB even when it was turned off in preferences. I don't know if also affected TIFF. But since you already are using compression, I don't see how that can apply here. And it didn't produce a halving of file size.

[PECourtejoie]

Hi, @Mike Pountney Can you install both versions of Photoshop, and convert the same file in both apps with the very same parameters, and report here (a view of the finder with the 2 files could be a good proof of the issue.)

Please also report all settings used. I could then convert this thread to a bug report.

[Mike Pountney]

Hi

So I loaded up the same RAW file to the latest version of Ps (v24.01) and saved as a TIFF file which stored as 114 MB

Then I downloaded the oldest version of Ps being offered (v22.2) and when I saved that as a Tiff file it loaded at 121MB

These are both about double the size that I was getting a few months ago

It occurred to me that the RAW converter file has been upgraded a few times recently - currently on version 15.0

Could that be creating these much larger TIFF files

Unfortunately The Creative Cloud doesn’t offer older versions of the RAW converter.

If this is the problem is there a way to overcome it?

Thanks

Mike

[Per Berntsen]

Check your workflow settings in Camera Raw, they are listed at the bottom of the screen.

If it says 16-bit, click the text to access the workflow settings and change to 8-bit.

If your doing heavy editing in Photoshop, it is recommended to use 16-bit. You can always convert to 8-bit later, or even better, keep the 16-bit file, and convert a copy to 8-bit if needed.

[PECourtejoie]

Yes, @Mike Pountney @could you open one of the old tiff files, and check its bit depth?

[Mike Pountney]

Thanks very much - that has definitely worked with approx a 50MB file instead of 100 MB.

I checked my old TIFFs and they were 8 bit depth. 

I assume the latest version of the RAW converter has "upgraded " to 16 bit ?

Is there any significant difference in the final image if I am printing up to A3 paper size usually

Mike

[Per Berntsen]

An 8-bit file can have 256 levels (shades) of red, green and blue.

A 16-bit file can have 65,536 levels of each color, which gives you editing headroom. In other words, you can do heavy editing without quality loss, which you can't with 8-bit files.

See https://www.photoshopessentials.com/essentials/16-bit/

Did you look at the workflow settings in Camera Raw like I suggested in my previous post?

You can also see at a glance if an image is 8 or 16-bit in Photoshop.

There is no advantage in using 16-bit files for printing, 8-bit will be fine.