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Inspiring
February 28, 2025
Question

Managing PSD file sizes when working with higher megapixel images

  • February 28, 2025
  • 3 replies
  • 1214 views

Hi,

 

I've just upgraded from a Nikon D500 (20.9 megapixel) to a Nikon D850 (45.7 megapixel) camera,  and almost immediately while editing in Photoshop, I've hit the 2GB limit of PSD files, and have had to switch to PSB files instead.

I think I may need to change my workflow to manage file sizes more effectively going forwards. Up until now, I didn't give it a great deal of thought (with the 20..9 megapixel camera)... creating layers whenever I needed to, and never hitting the 2GB limit.

 

I've already changed "Maximize PSD and PSB compatibility" to "Never" in the PS settings, which does reduce file sizes significantly. I'm not concerned with losing compatibility with old versions of Photoshop.

 

I'm also wondering, if I'm going to go over 2GB file sizes regularly, whether I should just always save in PSB format from the start, so I never have to be part-way through an editing process and have to change from PSD to PSB.

 

If anyone has got any tips on how to manage file sizes when editing large images, I'd love to hear them.

 

Thank you for your help

 

Liz

3 replies

Trevor.Dennis
Community Expert
Community Expert
February 28, 2025

Be aware that there Photoshop functions that will not work if backward compatability is turned off.  Free Transform Step & Repeat probably being the most notable.

Inspiring
February 28, 2025

Now that is something I didn't expect from turning off backwards compatibility. ... hmm...

Is it documented anywhere what all the affected functions are?

Conrad_C
Community Expert
Community Expert
February 28, 2025

Do you only open the PSB files in Photoshop and not in any other software? If Photoshop is the only software that opens the files, it’s OK to disable Maximize PSD and PSB compatibility. But if those PSB files need to work in other applications (e.g. Adobe InDesign, Adobe After Effects, Lightroom Classic, and non-Adobe apps that open Photoshop files), that option needs to be on.

 

Also, in Preferences / File Handling, make sure that the option Disable Compression of PSD and PSB Files is not enabled, so that compression is being applied.

 

Beyond that, there isn’t much else you can do except the usual: When practical, reduce the width and height in pixels, reduce the bit depth, don’t use more layers or Smart Objects than necessary…

D Fosse
Community Expert
Community Expert
February 28, 2025
quote

Also, in Preferences / File Handling, make sure that the option Disable Compression of PSD and PSB Files is not enabled, so that compression is being applied.


By @Conrad_C

 

Actually, this is a dilemma of sorts. You don't really need compression until the files get very big, like several GB - but that's the size range where compressed open/save times get absolutely unbearable, like several minutes. You could call that a rock and a hard place.

 

Personally, I disable compression and plan for disk space expansion as needed. Today you can get 20 TB server-class drives at fairly reasonable prices.

Inspiring
February 28, 2025

Yes... I've observed this myself.... image compression/decompression can be very slow for large files... no perfect solutions here!

D Fosse
Community Expert
Community Expert
February 28, 2025
quote

I've already changed "Maximize PSD and PSB compatibility" to "Never" in the PS settings, which does reduce file sizes significantly. I'm not concerned with losing compatibility with old versions of Photoshop.


By @MissLiz166425

 

You also lose compatibility with Lightroom Classic. I would recommend keeping compatibility on.

 

I use a 60 MP Sony, and I'm trying to get into the habit of always saving as PSB right from the start.

 

The problem is that both Photoshop and Lightroom are lagging a bit behind here. There should be a PSB option in Lightroom preferences "external editing", and there should be an option in PS preferences to save to PSB as default.

 

There's no other way around it. PSD stops at 2GB, and you won't know when you're hitting that limit until you're actually saving the file.

 

 

Inspiring
February 28, 2025

Thanks for the information, I was  unaware of the compatibility issues with Lightroom Classic when compatibility mode is turned off in Photoshop. . Useful to know. 

As it happens, that is also of no concern to me.... I only ever use Bridge and Photoshop. Bridge appears to work fine (so far) with compatibility mode turned off...

So the file size reduction is a definite gain for me.

Yeah, I think I'll be using PSB from the start.

 

Thanks

 

Liz

 

Per Berntsen
Community Expert
Community Expert
February 28, 2025

Another option is to use Tiff, which has a max file size of 4 GB.

The Tiff format is widely supported, practically all image editors (and probably most image viewers) can open tiff files.