Resizing the content of a smart object creates larger file sizes than if resized before adding as SO

[s51276083]

Hi,

I'm struggling to understand this phenomenon: 
I have proofs file made up of 12 individual smart objects.
I create them by adding the original large file as smart objects, then going into each SO and resizing the image layer to the proof print size. Just to reiteriate - I don't resize rhe SO, I resize the raster image layer inside it.
I'm not sure why this is, but it results in a file size 6 or 7 times larger than if I first creat the smaller size files and then add them as smart objects to the proofs file.
(The latter process is of course longer, which is why I prefer the first route.)

I can't understand why the file sizes of the proof files aren't identical for both of those processes, as you end up with smart objects containing identical resized images in both cases.

Can anyone shed a light on this?

Thanks in advance,
S

[c.pfaffenbichler]

Are the SO flat or do they contain something else than only a Background Layer? 

What are the pixel dimensions of the SOs and the containing document (prior to and after resizing)? 

A SO can easily add up to three times its »weight« (as indicated as »Image Size« in the Image Size dialog) to the containing document (and even more depending on its scaling and number of instances): 

• the instance 

• the actual SO content 

• the preview if the SO is not flattened

[s51276083]

Thanks @c.pfaffenbichler for your reply.

They're not flattened but the contents are similar (all photos go through the same process. If anything, some of the smaller proofs file have an additional layer in each of the SOs for sharpening). The resize (from around 6800 sq pixels down to around 1880) is done first before additional layers are added. There are no layers in there that are larger than the canvas size.

There are several files prepared in each of the two processes so I know that this isn't an anomaly with specific proof images in one file.

The only difference between the larger and smaller proofs files is whether I've resized the images before adding them as SOs or after. And the difference, is quite big (up to 6-7 times larger). 

Which doesn't make sense to me.

[c.pfaffenbichler]

Could you please attach two files (one before and one after the size increase)? 

[Bojan Živković]

"I don't resize rhe SO, I resize the raster image layer inside it."

If I understand you correctly then what is happening is normal. You place or open large image as Smart Object and it weights 60MB, for example. Image inside SO is 6000x4000px, for example.

Next you scale down image inside SO to 1500x1000px for prooof.

Next you resize image inside SO to 300x2000px and PSD file is heavier couple of times? It is normal because 3000x2000px is 4X larger of 1500x1000px.

Please correct me if I am wrong in my understanding.

[s51276083 · Accepted solution]

Hi Bojan,

Thanks for your reply. I only scaled the raster image down (and only once).

I have just realised why this has happened, and it was my mistake. I used a different image source and when I added those images as a SO first, they kept the raw data (it was nested twice which I had missed). When i fisrt resized and saved images before adding them as SOs, The raw data was removed. So it was my mistake. Once I stripped the raw data after adding the image as a SO, my image sizes were the same small size in both routes.

Thanks you all for your help and apologies for wasting your time.