Affinity Photo file size creates greater then 5X Raw files

[DanJM]

I've been using ON1 for photo editing for about a year now along side Affinity designer and photo. I was planing on using Affinity for all editing going forward but the files that have been treated by Affinity are so large that it gets me a little reluctant. I'm using a Sony a7R3 and the raw files are 80mb but the Affinity files that are created are over 5x what the raw files being edited. see the attached comparison of file sizes. 

[walt.farrell]

Welcome to the Serif Affinity forums.

1. What are the pixel dimensions of that image?
2. What color format is your .afphoto file (RGB/8, /16, or /32)?
3. Have you done anything to the .afphoto file after you pressed the Develop button?

[DanJM]

Setting from Affinity & data information for Finder

 

[walt.farrell]

Thanks, but the Affinity settings don't really give the needed information for the .afphoto file.

1. What are your settings for the Develop Assistant? (View > Assistant Manager, then you may need to click on the Develop Assistant button).
2. With an image in the Photo Persona after you've Developed it, what does the Context Toolbar show when you have the Pan Tool (Hand) selected?
3. Did you do anything after pressing Develop and before you did the File > Save to create the .afphoto file?

 

[DanJM]

 

 

 

[walt.farrell]

Thanks.

A rough calculation:

• The file from your camera is 7698 * 5320px at 16 bits per pixel which is approximately 80MB.
• The .afphoto file is 7698*5320px with 4 channels (R, G, B, A) per pixel. At 16 bits per channel per pixel (i.e., 64 bits per pixel), this is approximately 320MB, or 4x larger than the raw image.

Additionally, the .afphoto file will contain an initial Snapshot, which I would guess accounts for the additional data required to get to your total of 5x the size of the raw image file.

[DanJM]

Are you set up the same and are you getting the same size files

 

 

[walt.farrell]

My camera's raw files are smaller than yours, and so my .afphoto files are also smaller.

For one typical file, 4948 x 3280 px, RGBA/16 after developing:

• .nef file: 19,225 KB
• .afphoto file: 139,368 KB

Just based on calculations, it appears my camera uses about 10 bits per pixel in the raw image. So, for the raw file: 4948 * 3280 * 10 /1024 / 8 gives a rough size for the .nef file of 19,811 KB which is in the right ballpark. And for the .afphoto file, 4948 * 3280 * 64 / 1024 / 8 gives 126,792 KB which is also in the right ballpark.

139,368 - 126,792 leaves 12,576 KB unexplained. If I delete the snapshot and save it again the size is 111,280 KB, so the snapshot part of it is about 28,088 KB.

139,368 / 19,225 tells me that my .afphoto is about 7x the size of the initial raw file.

[Minus44]

So as you can see, while a RAW file is fairly hefty, it’s that way for a reason. The RAW file gives you access to data you can manipulate more easily and more readily than you can with an 8-bit JPEG photo. Similarly, the .AFPHOTO format is storing your image data in a container that holds not only the RAW image (if that’s what you started out with), but also additional custom data unique to Affinity Photo, giving you access to (often) non-destructive tools and features such as layer data, masks, Live Filters, etc. Again, super-hefty, but also super-useful. 🙂 

For what it’s worth, you probably won’t want to store all of your photos as .AFPHOTO files, but there may be good reasons to store some this way. I usually 

[kirkt]

I downloaded a sample ARW file form the a7rIII from imaging-resource.com.  I opened it in AP v 1.8.6 as a 16bit per channel file in the Develop persona and brought it into AP.  I saved the file as a .aphoto file.  It is 336MB, which makes sense given the large pixel dimensions and the 16 bit per channel encoding.

(7952 x 5304 pixels) x (4 channels) x (16bits per channel / 8 bits per byte) = 337 MB.  Close enough.

If you save the file as a 16bit TIFF in AP,  the file size is 203 MB, versus 253 MB, which is what the above calculation would predict for a 3 channel image (saving in PS with no compression yields a 253MB file).  AP might be using some compression or similar file-reducing strategy when saving to TIFF, I do not know.

Anyway, the large file size for a large pixel dimension raw file rendered to a 16 bit per channel RGB file is expected.  Remember that a raw file is only a 1channel image, in this case encoded at approximately 16bits per channel (yielding the 85MB raw file).  Once you demosaic the raw file and render it to a 3-channel 16 bit per channel RGB image, the file size starts to get big quickly.

When you use an application like OnOne, the large file that results from converting the raw image data is not saved to disc in a high-bit format if you do not need the large TIFF for editing outside of the application.  So, you never see the large files accumulate on your drive - they live in RAM until you render something smaller, like a JPEG to print or post to the internet.  When you actually save the large, high-bit image to disc, you realize how bit it is.

 

kirk

[walt.farrell]

2 hours ago, kirkt said:

AP might be using some compression or similar file-reducing strategy when saving to TIFF, I do not know.

That's under your control in the More... options in the File > Export dialog. The default is ZIP compression, which for me gives somewhat better size results than choosing NONE, and much better than choosing LZW, for the 16-bit image I just tested with.