tiff file shrinks in Affinity Photo

[grunnvms]

I'm using the free Capture One 2.3 for Fuji RAW converter in conjunction with Affinity Photo. I've been told that Fuji assisted in the development of this converter, so it is suppose to be the best RAW converter for Fuji.

I export the result as uncompressed 16 bit TIFF file, that way no information gets lost. It is automatically imported in Affinity Photo, where I can make more adjustments that are not enabled in the free Capture One.

I then export the image from Affinity Photo, again as uncompressed 16 bit tiff file.

One would assume that the export file of Capture One and the export file of Affinity Photo have about the same size, after all I did not change the size of the image, and both export files are uncompressed 16 bit tiff files.

However, the export file from Capture One has a size of about 150 kB, and the export file from Affinity Photo has a size of less then 100 kB, so quite a difference.

I did notice that all of the export files of Capture One have exactly the same size, whereas the output files from Affinity Photo differ in size.

Could there be 'empty space'  in the Capture One tiff files?

[Paul Mc]

Try loading and saving your processed RAW file without any adjustments to see if that shows the same difference in file size.

Try reloading the newly saved file and the original. Put the original on another layer and then use a difference mode on the top layer. Check the viewport and histogram. If you see black everywhere then you probably have an equivalent image file even if they saved at different sizes. 

I'm no expert in Capture One but I believe you can compare before and after adjustments. Maybe you can compare the Affinity Photo saved file to the freshly converted RAW image?

You probably know this but there is also lossless compression which results in a smaller file than uncompressed but should be equivalent when viewed.

[James Ritson]

Hi @grunnvms, the difference in file size is likely due to Affinity Photo applying lossless ZIP compression by default. You can change the compression method or disable it entirely when using File>Export by scrolling down to the Advanced section: it's at the bottom of the settings.

It certainly sounds like Capture One isn't applying any form of compression, as you've observed that its output file sizes are all consistent.

Rest assured, you're not losing any information. You may gain a slight increase in encoding speed by not using compression when exporting from Photo—it's up to you whether the increased file size is an acceptable trade off. Here's the export dialog with the compression option:

[grunnvms]

Hi James,

No, I had compression disabled with Capture One as well as with Affinity, I checked. Unless of course there is a little bug in Affinity that makes it compressing the image even if compression is disabled. 

What I meant to say is that TIFF is a lossless file type, contrary to JPEG. That's why made the choice for 16 bit TIFF. I also know that compressing a TIFF file is lossless as well, and that specifically for 16 bit TIFF you should always use ZIP, and never LZW, since LZW can make the resulting fille bigger instead of smaller, at least so I've read.

By the way, when exporting a document the default pixel format is visible, in my case RGB 16 bit. However, the ICC profile setting is empty, I would expect to see " use document format"  as default. 

[walt.farrell]

Perhaps you could supply 3 sample files, @grunnvms?

1. The TIFF created by Capture One.
2. A .afphoto saved from Photo, with your adjustments.
3. A TIFF exported from Photo, with your adjustments.

[grunnvms]

Hi Walt,

No problem.

These are the three files, and I made no adjustments in Affinity Photo to make them 1:1 comparable. 

Affinity test.afphoto Affinity test AP.tiff Affinity test CO.tif

[walt.farrell]

Thanks.

1. Looking at exiftool output, one difference is that Capture One included about 51KB or TIFF Thumbnail, which Affinity Photo did not provide. But that can't account for the difference in file sizes, which is more like 53MB. Both are uncompressed.
2. Overlaying all the files, and using ithe Difference Blend Mode, all 3 seem to have identical pixel content.

So I have no idea how to account for the difference in file sizes. Sorry.

[David in Яuislip]

This is what I get, all files 16bit uncompressed, ICC profile & metadata included
95,908,364 Affinity test CO-PhotoV1.tif
95,913,688 Affinity test CO-Photoshop.tif
151,053,778 Affinity test CO.tif

to be continued

[- S -]

20 hours ago, grunnvms said:

"…One would assume that the export file of Capture One and the export file of Affinity Photo have about the same size, after all I did not change the size of the image, and both export files are uncompressed 16 bit tiff files.

However, the export file from Capture One has a size of about 150 MB, and the export file from Affinity Photo has a size of less then 100 MB, so quite a difference."

The TIFF file exported from Affinity Photo is 91.4 Megabytes.  This is around the file size I would expect for an uncompressed 16-bit RGB TIFF file of that resolution (give or take a bit for metadata and embedded thumbnail).  I.E.

4896 × 3264 = 15,980,544 pixels


15,980,544 × 48 (bits per pixel) = 767,066,112 bits

767,066,112 ÷ 8 (bits in a byte) =  95,883,264 bytes

95,883,264 ÷ 1024 = 93,636 Kilobytes

93,636 ÷ 1024 = 91.44 Megabytes

Therefore, I think Capture One is storing extra data in the TIFF file for some reason.  Looking at the metadata of your TIFF file using ExifTool, it lists the below properties – which I think is likely where the issue lies.

[IFD0]          TileWidth                       : 2048
[IFD0]          TileLength                      : 2048

Looking at the Capture One help page (LINK HERE), it appears to have an export option for "Tile Dimensions".  I think the reason for the extra file size is that you're exporting the image from Capture One with "Tile Dimensions" set to "2048".

I would suggest going into the Capture One export options and changing it to "Not Tiled".  The exported file size from Capture One will then likely be around 91.4 Megabytes – the same as Affinity Photo.
 

[grunnvms]

Indeed, it is the tile setting !

It adds extra layers in the tiff file, that can be used for all kinds of reasons. Google for " tiff tiles", and you will find a long explanation.

Removing the tile setting, and just export as uncompressed will indeed result in a file size comparable with the output of Affinity Photo or Photoshop.

Thanks !!