How can I disable the image preview on PSDs?

[johnivanwhite]

Hi Folks,

I'm trying to disable the image preview on PSDs, but it doesn't work.

More and more these days I reduce PSD file sizes with a white layer at the top when I save. That shaves huge amounts off the file size. Lie 115MB down to 75MB!

I tried disabling image preview in settings but it has no effect at all.

Hoping someone can help

John

[davescm]

Interesting - I just added a white layer to a few PSDs to try it and the file size increased in each (I tried with PSD compression bothh enabled and disabled).

To your question if you go to Preferences>File Handling and set Maximise PSD and PSB compatibility to "Never" then it does not save a flattened preview in the PSD. Be aware though that if you use Lightroom though the preview is required.

To be honest I am not worried about file size - hard disk storage is cheap, so I always have the Maximise compatibility set . I also disable compression on PSDs and PSBs as the trade of is a larger file but quicker opening times.

Dave

[johnivanwhite]

Hi Dave,

I suspect your PSD files are pretty small, so that adding a layer adds considerable data. With a 115MB file it really cuts it down massively.

I don't use Lightroom but I will have an issue with PSDs that are placed into InDesign—because they won't display.

I never knew there was a 'compress' facility!

I'll try "Maximise PSD and PSB compatibility to "Never"" now. Never saw that before!

Thanks

John

[davescm]

johnivanwhite  wrote

Hi Dave,

I suspect your PSD files are pretty small, so that adding a layer adds considerable data.

I tried it with 156MB , 142MB, 195 MB and 2.8 GB files (the last being PSB)

Dave

[JJMack]

Have you tried  using Never saving  PSD.  If you do some applications like LR will not be able to do anything with the PSD. Your white layer should also mess up Lightroom for it does not  have layer support it can only  use the composite image that may be in PSD files. LR would only see your image is white.

I do not use LR but I do use old version of Photoshop so I always save them....

[johnivanwhite]

Hi JJ,

Yes, I used 'Never' under 'File Saving Options > Image Preview'. It seems to do nothing.

Thanks for your help with the "Maximise PSD and PSB compatibility to "Never""

John

[Trevor.Dennis]

Hi JJ,

Thanks for your help with the "Maximise PSD and PSB compatibility to "Never""

John

By @johnivanwhite

An old thread I know, but I know of at least one function that will not work if you turn off file compatability.  I once spent a frustrating couple of days unable to make Displacement Maps work until (I think it was John) told me about this wee gotcha.  

From what I can remember from the years using this forum, my impression is that most of us turn off file compression for .PSD and .PSB files.  Although, now I think about it, drives are so incredibly fast nowadays, we could probably put up with the tiny wait to load large files, and win back a bit of drive space.

[johnivanwhite]

Blast, disabling "Maximise PSD and PSB compatibility to "Never"" didn't work either. The file still has a Preview and is still huge.

John

[johnivanwhite]

There's really something wrong here.

It's telling that when i saved the PSD, I wasn't 'asked' if I wanted to "Maximise PSD and PSB compatibility despite setting it to do so.

Maybe I need to delete my preferences file and set it up again from fresh?

[D Fosse]

There is no way adding a layer can reduce file size, white or not. It can only add to the file size, all else being equal. Which it can't be in your case.

As for file sizes in general, I usually say that if that's a concern, you're in the wrong business. If you're working with image files, prepare for massive storage space.

[johnivanwhite]

D,

I'm surprised that you would come on this thread and suggest that what I've asserted in here, more than once, is untrue. I actually do this and it works—dramatically. Turning off the visibility of all layers has the same effect, but because that is so inconvenient to do, my solution uses a white layer.

If it didn't work, believe you me, I wouldn't waste my time doing it—and stating that it does work on here.

[D Fosse]

Well, I just saved a PSB at 2.6 GB.

I then added a blank white layer, no other change. It is now 3.7 GB.

If you see size reduction, It's because compression is on in one of them and off in the other.

[johnivanwhite]

D,

You seem quite sure that "compression is on in one of them and off in the other." withouth even seeing how I did it.

I saved and re-saved the same file within a couple of minutes, changing no settings. I never even knew about PSD comprssion until an hour ago when it came up in this thread.

I doubt that adding a white layer or not, will automatically affect a checkbox in the settings.

Perhaps you—and Dave above—don't use this PSD compression, and that might make the white layer ineffective.

John

[davescm]

I've just tried this with five files - to some I added a white pixel layer to some a white color fill layer. All have PSD and PSB compression set.

No white                     Add White

185,597kB                 195,362kB
142,403kB                 142,417kB
74,567kB                   141,259kB
161,196kB                 161,213kB
1,489kB                      1,614KB

[johnivanwhite]

Bizarre that it doesn't work for you folks.

I just did a web search and found that other people do what i do and get file size savings.

https://creativemarket.com/blog/the-best-tricks-to-reduce-photoshop-file-size

My question now is: Why don't the 'File Handling' settings that you folks recommended to me, take effect? I restarted Photoshop, no joy. The PSDs still save with preview images.

This is a pretty up to date CC Photoshop by the way, on an OSX iMac.

Thanks,

John

[johnivanwhite]

D,

2 screenshots for you of the same illustration file in my iMac's Finder. One without my white layer, and one with it.

John

BEFORE:

AFTER:

[D Fosse]

Then a smaller file: 307 MB versus 415 MB.

[johnivanwhite]

It's funny, I've been using Photoshop for years and I forgot all about this checkbox in the save dialog box (screenshot)

It has no effect whatsoever. I'm going to check for a Photoshop update now.

John

[davescm]

Hi

I'm on Windows not Mac. There is discusion here on image previews related to Mac. It starts from a different premise i.e. some not seeing the previews but it may help. .:

Photoshop CC: Not seeing finder thumbnails on MacOS (MacOS issue) | Photoshop Family Customer Commun...

Dave

[Jeff Arola]

I believe on macOS/OS X, Finder automatically creates previews of flattened psds or psds saved with

Maximize Compatibility (saves flattened copy in addition to the layers).

Of course if differs on lots of factors like the size, whether there are alpha channels, the version of photoshop, bugs in the os, etc.

Windows doesn't preview psd files as a general rule unless one installs a third party codec or has an old version

of photoshop (cs3 and older) that included the Psicon.dll file that generated psd previews.

[Test Screen Name]

I can see why, technically, adding a white layer could reduce the size of a PSD. Note that the white layer needs to be in FRONT and obscure the picture (i.e. so it must be removed to continue working!)

1. A normal PSD contains a raster image of each layer, and of the composite view (except where there is only one layer).

2. These images are compressed.

3. Clearly a white image will compress to almost nothing. So adding a white layer won't much increase the overall size of the layer images.

4. If the composite is now white, it will now compress to next to nothing.  So the image may well get smaller, if it started with more than one layer.

These are not generally called previews, a preview is something else, so there has been a lot of talking at cross purposes.

The reason for the composite image is for compatibility with older/simpler software that can't read and process Photoshop layers.

So, if you turn off the composite image, some software (perhaps including Finder) will no longer preview PSDs. So it isn't a preview, but it ENABLES previews.

The "maximize compatibility" save option controls a number of things, one of which is the composite image.

[davescm]

I fully understand the theory of why a white layer might reduce the file size, by allowing greater compression of the composite. However, in testing a range of my own files in varying pixel sizes, image content and number of layers I was unable to find any where the file size was reduced by this method. All the examples I tried, trying both color fill and pixel layers filled with white, increased in size. So the additional white layer took up more space than the space saved by the additional compression on the composite.

I think it's one of those - try it if you want to methods. If it works on your image then fine but don't assume it will work in all cases.

Personally, as I said earlier, I value compatibility and quick opening over file size. Disk space is cheap these days. I might of course  think differently if I was regularly sending multi layered PSDs over the internet.

Dave

[D Fosse]

So two conditions have to be met: Max compatibility has to be on, which you pretty much need anyway for use in other applications.

But then compression also has to be on, otherwise, an added white layer is just an added layer. I keep compression off, so my numbers may not be relevant.

Still, it's hard to see how the saving in a compressed white composite layer can outweigh the size of an extra layer. It might in some very special cases when the planets are in exactly the right configuration.

Image previews have basically nothing to do with this, unless the file is very small so that the preview is a large proportion of it.

[Test Screen Name]

" it's hard to see how the saving in a compressed white composite layer can outweigh the size of an extra layer."  I did some tests a while back, and my recollection is that a monochrome layer adds almost nothing to file size.

[johnivanwhite]

Well, it's all reached a level of strangeness now which makes all of our discussion here even more difficult. I'm now finding that a PSD is saving at 116MB instead of 164MB no matter what I do in terms of settings or layers. Even a flat yellow top layer set to soft-light and set to be not visible is showing in the previews. Absolutely bizarre!

To make things even weirder, some PSDs from a couple of years ago had no preview in the Mac finder, and looked white, even though I had no white layer in the top of them!

I updated Photoshop yesterday, but I might uninstall it, delete the preferences file, and re-install and see what happens.

I think we've all ended up talking at cross-purposes here, understandably, and these latest Photoshop behaviours today, are complicating it still further.