Photoshop Cs and adjustment layers adding to file size

RL
Posted By
Roger_Lieberman
Nov 10, 2003
Views
1189
Replies
30
Status
Closed
I have just installed CS and under preferences i stated never to meximize compatability. Despite this when adding an adjustment layer the file size doubles so that I quickly have files of 150 mb and therefore everything slows down. This did not occur with PS 7. I have a P3 processor with 750 mb ram.
Any ideas?
Thanks
Roger Lieberman

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I
Iverson
Nov 11, 2003
I’ve had the same experience. When I was at PhotoPlus in NYC a week ago, I asked the Photoshop project manager about the problem. He said "send me an e-mail." I did (with full details), he replied, "I’ve forwarded your message to my engineers." A week later, nada. Very puzzling — if everyone was running into this, I’d expect to have seen it in a lot of forums, user groups, etc. I haven’t, but I’m having the problem, and so are you.
If you get an explanation, I’d love to hear the answer.
Bill Iverson
D
DavidMadison
Nov 11, 2003
My 100.3 mb 16 bit file goes up to 267.5 mb with the addition of one curves adjustment layer!

Athlon 1200 mhz 1.5 gb ram Windows 2000 sp4 Photoshop CS.

David Madison
D
DavidMadison
Nov 11, 2003
It seems the humungous size goes away when the file is dropped to 8 bit….so perhaps a problem in 16 bit code?

Anyone else noticing this in 16 bit or 8 bit???
I
Iverson
Nov 11, 2003
At least the problem is consistent — I tried with several different type adjustment layers, and with one or two layers, and in 16-bit, I got a 167% increase from the original file size with each layer (i.e., with one layer, the file size is 267% original size, with two layers it’s 434% original size — which makes for pretty big files if you start with a 120 Meg 4000 dpi scan from a 35mm frame. I’m sure there’s an easy answer, but until I find it, adjustment layers are simply not available in 16-bit. (And, yes, there’s no similar problem in 8-bit)
D
DavidMadison
Nov 12, 2003
Is it correct to infer from the silence from Adobe persons who normally respond quickly in this forum that this problem is an acknowleged bug?
I
Iverson
Nov 12, 2003
Not so. I’ve been told their engineers find only a 1/3 increase in fle size with a 16-bit adjustment layer, and they’re baffled by the problem I experience, but still looking for explanations.

I think you said you have 750 MB of RAM. What size 16-bit file were you adding an adjustment layer to? (I wonder if Photoshop might be reacting this way because it’s running into a memory problem, and having to go to the scratch disk)
D
DavidMadison
Nov 12, 2003
It was a 100.3 mb file in 16 bit. It became 267.5 mb with a single curves adjustment layer.

I have 1.5 GB of RAM.

David Madison
GM
Glenn_Mitchell
Nov 12, 2003
Am I missing something?!?!

Of course your file will increase in size if you add a layer in Photoshop CS. Each layer will — at a minimum — double the file size.

In previous versions of Photoshop, you had to convert to 8 bits to use an adjustment layer. That cut your file size in half. Then if you added an adjustment layer, that file would double in size.

If you did not perform a save between the 8-bit conversion and adding a layer, your new file would be the same size as your old file or just a little bigger. (OriginalFileSize / 2)*2 = OriginalFileSize

Where’s the confusion? Your file should increase for each layer you add. If you start off with a 30MB file and add a layer, your file should be 60MB. Each additional layer should add 30MB more.

No question, the overhead from layers can add up quickly. Especially in 16 bits.

All the additional flexibility comes at a price. 😉

Cheers,

Mitch
I
Iverson
Nov 12, 2003
That’s not the way adjustment layers worked with 8-bit files in earlier editions of Photoshop or in CS — try it.
CB
Cathy_Brown
Nov 13, 2003
Opened a 16-bit tiff straight from C1 at 36.1M. Added a curves adjustment layer and file size went to 96.3M. Then, just for the hell of it, added a hue/sat layer and file size went to a whopping 156.5M.

So, a 167% increase in file size for adjustment layer 1. Layer 2 increase that size by another 63%. Total increase with the 2 adjustment layers: 334%.

Now I’m on a roll. Added another curves layer. Now the file size is 216.7M. That’s about a 38% increase over previous size and now with 3 adjustment layers a 500% increase over start.

Adobe, is there any reason 16-bit adjustment layers should behave so very differently from 8-bit adjustment layers?
D
DavidMadison
Nov 13, 2003
Glenn,

Am I missing something?!?!

Yes…..

What you are saying is true only for layers full of pixel data such as a copy of your background layer. Adjustment layers are essentially math layers with no pixel data. File sizes do not double with adjustment layers, at least not with PS 7.

David
RW
Russell_Williams
Nov 13, 2003
For the folks reporting these large file size increases, are you looking at the actual size reported by the Finder or Explorer once the file is saved to disk, or the "doc size" number inside Photoshop?

The expected increase in actual file size for adding an adjustment layer with a solid white layer mask to a single layer document, saved in psd (with "maximize compatibility" off in the preferences) should be very little, because the solid white layer mask is compressed.

The layer mask is essentially one channel, so if it has pixels of complexity comparable to the main image channels, we would expect the file size to increase by approximately 1/3, since you’ve added one channel.

Other possible sources of confusion here are if you’re saving in file formats with different kinds of compression allowed for the main image data and the layer data. And saving as TIFF is like saving as PSD with "maximize backward compatibility" on. In that case, a flat document just has to be saved once. If you add an adjustment layer, the composited version has to be saved, then another copy of the pre-adjusted data has to be saved, and the data for the adjustment itself has to be saved. That means that adding a single adjustment layer to a flat document and saving as TIFF will *at least* double the file size.
D
DavidMadison
Nov 13, 2003
It is the size reported by doc size on the task bar in PS.

It occurs with a single adjustment layer of curves with an all white layer mask as is created automatically when you add an adjustment layer.

David
CC
Chris_Cox
Nov 13, 2003
David – the doc size in the task bar/bottom of the window is showing the expected size then. (16 bit data doesn’t compress well)
CB
Cathy_Brown
Nov 13, 2003
Russell, I’m reporting the "doc size" number inside PS8.

Since you think tiffs may be a problem, I’ve rerun the test on a psd of the same image. Results are slightly better, but basically similar.

Opening size 16-bit psd: 32.2M
add one curves adj. layer: 86M (167% increase)
add a hue/ sat adj. layer: 139.8 (63% increase)
add another curves layer: 193.6 (38.5% increase)

With 3 adjustment layers total increase in file size as shown within PS8 doc size display is 501%. "Maximize compatibility" is turned off.
D
DavidMadison
Nov 13, 2003
I just tried it again.

Open a 16 bit file, it is 198.5 mb on the file doc info on the task bar. In Explorer, that file is 203 mb

Add a curves layer with all white layer mask. Goes to 529 mb as reported on task bar.

Discard layer mask, goes to 463 mb on task bar. Restore layer mask, goes back to 529 mb.

Save the file (with layer mask). In Explorer, it is 362 mb.

Save the file after discarding layer mask. In Explorer it is 362 mb.

So…..obviously the expected file size function of the taskbar is not too accurate; and the addition of a single adjustment layer results in an 82% increase in saved file size!

David Madison
GM
Glenn_Mitchell
Nov 13, 2003
Well, I got an education about the size of PS layers. Cool! Thanks, David.

More data to consider . . .

I just loaded a file. 37MB 16-bit TIFF.

I added a levels adjustment layer. PS CS indicated an expected size of 96MB. It was 64MB. Same with a hue/saturation layer. Just a few bytes difference.

Clearly, an adjustment layer contains more than just math. It would also contain at least a mask. But it appears there’s considerably more than a mask and math to go from 37MB to 64MB. Even an uncompressed grayscale mask would only add 18.5MB to the file.

I reloaded the file. Added a duplicate layer. PS CS indicated an expected size of 84MB. It was 91MB. That indicates considerable overhead beyond the pixels, too. Another 50%, it seems.

Wierd!

I’ve said enough. I’ll listen and learn now. 😉

Cheers,

Mitch
GM
Glenn_Mitchell
Nov 13, 2003
OK. One more comment.

It looks like there is about 50% overhead for any data added by a layer.

Consider my examples . . .

37MB goes to 64MB with adjustment layer. If the mask is uncompressed and 18.5MB, another 50% gives you 27.75MB for the layer. That would give you approximately 64MB.

37MB goes to 96MB for duplicate layer. 37MB plus 50% gives you a 55.5MB layer for a total of 92.5MB.

Only two examples but an interesting pattern. 🙂

I’ll wait for Chris Fox to explain what’s going on. 🙂

Cheers,

Mitch
CC
Chris_Cox
Nov 13, 2003
Mitch – there is no "expected size".

The size you’re seeing in Photoshop is how much memory the image is using IN PHOTOSHOP. It has no direct relation to the image size when saved to a file.

Files include a lot of other data, possibly some compression, and possibly duplicate versions of some data (especially when you add the first layer).
DM
dave_milbut
Nov 13, 2003
Clearly, an adjustment layer contains more than just math.

An adjustment layer also seems to include a mask. Maybe that’s where your "extra" data is coming from.
GM
Glenn_Mitchell
Nov 13, 2003
OK, Chris. Thanks for the info.

I created two adjustment layers. Same 36MB TIFF. Layer adjustment followed by Hue/Saturation adjustment.

PS CS claims 156MB for the file in memory. File was just slightly larger after second layer. First layer took it to 63,771KB and the second layer took the file size to 63,790KB. That’s consistent with your statement that the first layer adds considerable overhead.

It looks like the second layer only added math and some housekeeping stuff like the layer name. Only a 19KB increase in size for that second layer.

Since both use a mask, entirely white in both cases, it looks like there is some sort of compression of the data in the mask once you get to the second layer. I even painted on both masks. That took the file size to just 64,160KB. A tiny increase.

Thanks for the education, Chris! You’re a big help!

Cheers,

Mitch
D
DavidMadison
Nov 13, 2003
An adjustment layer also seems to include a mask. Maybe that’s where your
"extra" data is coming from.

An adjustment layer can include a mask. The mask can be deleted. Doing so reduces the file size increase somewhat as I reported previously, however the test I did left an 82% increase in saved files size with the addition of one adjustment layer WITHOUT mask.

David
AW
Andrew_Werth
Nov 13, 2003
For what it’s worth, I’m seeing the same behavior…

I load a 16-bit RAW file (shot with a Canon 10D) into Photoshop CS using the new Camera RAW feature. I then cropped the image.

The status bar is set to show "Document Sizes":

With just the background layer: 20.2M / 20.2M
File size on disk: 20,677 KB

If I add 1 Curves adjustment layer, no mask: 20.2M / 47.1M File size on disk: 38,104 KB

If I convert to 8-bit mode: 10.1M / 10.1M
File size on disk: 10,221 KB

Seems like a bug — adjustment layers lose a lot of their benefits if they become fully instantiated pixel layers.

Andrew
F
Frogiswrong
Nov 13, 2003
I beg to differ.
I have always known that file size doubles with ANY extra layer since i can remember, versions 4 thru 8 on both PC & Mac.
I cant understand what all this fuss is about.

wrote in message
Glenn,

Am I missing something?!?!

Yes…..

What you are saying is true only for layers full of pixel data such as a copy of your background layer. Adjustment layers are essentially math
layers
with no pixel data. File sizes do not double with adjustment layers, at least not with PS 7.

David

I
Iverson
Nov 13, 2003
This is primarily a reply to Russell Williams post. First, what I’m seeing (and others seem to be seeing) is that each adjustment layer increases the file size as shown in the lower left display box by and amount equal to 167% percent of the original file (i.e., the file size goes to 267% of original with one layer, 434% of original with two layers, etc.)

I haven’t checked whether that’s the resulting file size when actually saved, but will. However, that still leaves me several questions and problems:

(1) Prior photoshop versions didn’t give such a mismatch between indicated size and actual when-saved size (certainly not for 8-bit adjustment layers)

(2) Prior versions did not increase file size by 1/3 when an adjustment layer with a reveal-all (i.e., white) mask was added — the increase in the file size as displayed was zero, nada (and I’m pretty sure this was true when saved, since I often have two such adjustment layers to set B/W point and gray values, and I’d notice a 2/3 increase in file size, given my somewhat memory constrained system).

(3) I’ve heard that the "expected" file size increase in CS is about 1/3 because 16-bit layers don’t compress as well as 8-bit. Don’t have the technical background to know about that, but if true it suggests that 16-bit adjustment layers will swell file sizes substantially more then 8-bit layers, and that doesn’t bode well for those of us who don’t have 2 gigs of memory and rambo processors (even assuming the current unpleasantness over 167% adjustment layers can be solved)
CC
Chris_Cox
Nov 13, 2003
Yes, Photoshop tries to compress image data in memory. But 16 bit data doesn’t compress well, and some of our "don’t store constants" logic doesn’t work for 16 bit values yet. (Hey, I didn’t have time to work out ALL the kinks)

None of this has changed from previous versions.

The only thing that has changed is that 16 bit/channel images can now have layers – and you’re seeing the lack of compression in 16 bit/channel data. The good news is that I was able to do better 16 bit layer compression in PSD, PSB and TIFF files.

And the document size in memory has NEVER had a direct relationship to file size. There are too many other factors involved in the file formats.
GM
Glenn_Mitchell
Nov 14, 2003
Chris:

I think you and your team have done a splendid job! 🙂

I am grateful that we can now work with layers in 16-bits! It literally changes life as I knew it.

Progress does take time. Now that you have the functionality, future releases can work on adding efficiency in storage, etc.

Cheers,

Mitch
SB
simon_b_knight
Jan 1, 2004
I had the same problem. I don’t think that the ‘never’ setting in file compatibility is working when you save. If you ‘save as’ or use the ‘ask’ option and uncheck the maximize compatibility box the file does not grow due to the adjustment layers.
MM
Mick_Murphy
Jan 1, 2004
This is not just with 16 bit files. I’ve been seeing the same thing with 8 bit files ever since I got CS. It’s definitely a bug but it’s not consistent. I Save As and overwrite the existing file to bring it down to normal size from approximately double.
SB
simon_b_knight
Jan 1, 2004
I am seeing it with both 8 bit and 16 bit files.

MacBook Pro 16” Mockups 🔥

– in 4 materials (clay versions included)

– 12 scenes

– 48 MacBook Pro 16″ mockups

– 6000 x 4500 px

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