Photo 2 - Photoshop file size reduced when "save as" or export

[Calico]

Hello. I'm trying to switch from Photoshop to Affinity. Used Affinity Photo 1 very occasionally on my Mac laptop for past few years. Just got new Mac Studio (desktop) and installed Affinity 2.

I'm confused about what is happening to image file sizes when I export or "save as."

When I import a Photoshop tiff file into Affinity, then either export it or "save as", the file size is reduced, even when I export or save as with all the layers, keep 16 bit, choose no compression, don't change image size, etc.

For example, I imported a tiff from Photoshop which had three layers and was 577.6 MB.

As experiment, I did not modify the file at all (did not change size, did not modify image, nothing) and exported and "saved as".

When exported as tiff, with lanczos (tried both sep and non-sep), 16 bit, no compression, the file became 321.2 MB. 

When I did a "save as," it became "afphoto" file (I didn't have a choice of file type) and was then 111.6 MB.

I also tried exporting as PSD file with both "preserve accuracy" and "preserve editability," and those files were 374.9 MB.

So none of the files coming out of Affinity were the file size of the original Photoshop tiff file -- all smaller, with the afphoto file being the smallest.

When I bring the exported or "saved as" files back into Affinity, they still have the layers. So it isn't that files got flattened.

Is Affinity compressing, even though I'm saying not to? Or what is going on?

Also, I can't see the file size (in megabytes) anywhere in Affinity when the file is open, as I could in Photoshop. Am I missing it? I see the megapixels number in top left corner. For all of the above files with varying MB sizes, the megapixels number was the same: 34.95 MP.

Confused.

Thanks for any help.

 

 

[walt.farrell]

10 hours ago, Calico said:

Also, I can't see the file size (in megabytes) anywhere in Affinity when the file is open, as I could in Photoshop. Am I missing it?

Welcome to the Serif Affinity forums.

As I see it: That size, in megabytes, only makes sense when the file is on disk, not in memory. And the file size on disk is only determined when you Save or Export it and choose the file type and options. Thus, so it doesn't really make sense until then, so the Affinity apps do not show it. If you want to know the size it had when you Opened it, you can look in File Explorer or Finder.

I don't have an answer for the rest of your questions, but I will point out that:

1. TIFF files don't have Layers natively. They can store "chunks" of data in addition to the pixel and metadata info. And some applications use that capability to store what they call "layers", but they are really just application-specific data. This data is in proprietary formats that may or may not be documented, but the format is not part of the TIFF standard.
2. Photoshop basically puts a PSD inside the TIFF if you ask it to save layers. Affinity apps can read that, in the same way and with the same limitations as they can read PSD files directly.
3. If you Export a TIFF with Affinity layers, you basically get a TIFF with an afphoto file embedded in it. Only Affinity applications (and possibly the few other apps that have figured out the afphoto format) can read that data. All others will read only the pixel and metadata information.
4. If you open a TIFF with PSD data and then Save, you have a file with layers. Affinity apps will ask if you want to flatten it (basically just retaining the pixel data) or Save As. If you Save As, you get a .afphoto file, and that is correct and intentional.

[Calico]

1 hour ago, walt.farrell said:

Welcome to the Serif Affinity forums.

As I see it: That size, in megabytes, only makes sense when the file is on disk, not in memory. And the file size on disk is only determined when you Save or Export it and choose the file type and options. Thus, so it doesn't really make sense until then, so the Affinity apps do not show it. If you want to know the size it had when you Opened it, you can look in File Explorer or Finder.

I don't have an answer for the rest of your questions, but I will point out that:

1. TIFF files don't have Layers natively. They can store "chunks" of data in addition to the pixel and metadata info. And some applications use that capability to store what they call "layers", but they are really just application-specific data. This data is in proprietary formats that may or may not be documented, but the format is not part of the TIFF standard.
2. Photoshop basically puts a PSD inside the TIFF if you ask it to save layers. Affinity apps can read that, in the same way and with the same limitations as they can read PSD files directly.
3. If you Export a TIFF with Affinity layers, you basically get a TIFF with an afphoto file embedded in it. Only Affinity applications (and possibly the few other apps that have figured out the afphoto format) can read that data. All others will read only the pixel and metadata information.
4. If you open a TIFF with PSD data and then Save, you have a file with layers. Affinity apps will ask if you want to flatten it (basically just retaining the pixel data) or Save As. If you Save As, you get a .afphoto file, and that is correct and intentional.

Hi Walt,

Wow, I had no idea there was so much going on with tiff files. PSD files are inside tiff files if there are layers? That's interesting, as is everything else you said. Shows me that "saving as" or exporting a tiff isn't as straightforward as I had thought, so if their file size changes, it shouldn't be surprising. I will stop worrying about it. I was just worried that the file was being compressed. I have only worked in Photoshop for many years so only knew what happened there.

Something else that confuses me....which may be related to what you're saying about tiffs and afphoto files:

When I export a tiff as tiff in Affinity (not resizing the image), I have to choose a resampling style (bilinear, bicubic, Lanczos - separable or non-separable). In Photoshop, I didn't do this. Only had to choose resampling style when I was resizing the tiff.

In Affinity, if I "save as," the file automatically becomes afphoto file, and I do not have to choose a resampling style.

So are tiffs that are exported from Affinity always resampled? But they weren't in Photoshop? And the only way to export without resampling in Affinity is to save as afphoto file?

Thank you so much for sharing your knowledge.

Kat

 

Edited January 16, 2023 by Calico

[walt.farrell]

I'm not sure about your resampling question. I think that the resampling only occurs when the dimensions (in px) or the color format is changed. But someone else will have to say for sure.

Also, on a technical terminology note: you cannot Export a .afphoto file. You can only Save them. Export is used for files that are not native Affinity formats.

[Calico]

1 minute ago, walt.farrell said:

I'm not sure about your resampling question. I think that the resampling only occurs when the dimensions (in px) or the color format is changed. But someone else will have to say for sure.

Also, on a technical terminology note: you cannot Export a .afphoto file. You can only Save them. Export is used for files that are not native Affinity formats.

Actually, before I read your reply, I noticed I had made the mistake of saying "export as afphoto" instead of "save as afphoto" and edited my comment!

Re resampling....it does seem that resampling should only happen if image resized or changed in some other way, but in window where you specify things for export, you do have to choose resampling style, even if you haven't made any changes (as I did in my test). Maybe Affinity just assumes you have made changes? But I wouldn't think all types of changes should require resampling.

Thanks.

[Affinity Info Bot]

The issue "Non Live Filters are prompting the app to ask if the user wants to save a TIFF with layers or flattened" (REF: AFP-5635) has been fixed by the developers in internal build "2.1.0.1742".
This fix should soon be available as a customer beta and is planned for inclusion in the next customer release.
Customer beta builds are announced here and you can participate by following these instructions.
If you still experience this problem once you are using that build version (or later) please reply to this thread including @Serif Info Bot to notify us.