Moonie

Not sure if it's a bug, or it was designed as such. Either way, I've tried as per RC-R's suggestion and it worked! In short, I selected the RAW then clicked on edit on the upper right, then clicked on extension (5th icon from the top right screen), and it goes to Affinity's Develop, after which I could proceed as per normal.
 
As for right clicking and choosing to Edit with "Affinity", what owenr says make sense to me. Only that I have problem saving the edited file back to Mac Photo. 
 
@John Rostron so when I open using the right click edit, the file opens as TIFF, which was indicated at the tab above and it doesn't open in Develop.
 
I am guessing we've found a solution now? :-D Thanks all for prompt replies and great feedbacks! Special thanks to R C-R! Time for editing :-D

Hi Moonie,
Welcome to Affinity Forums
Can you please upload one of the RAW files so we can check this here?
All files will be deleted after being checked. Thanks.

I saw this post and tried to replicate the above and yes the RAW is converted to a TIFF.  However I also had a few photos from my previous Sony A7R, and they too open as  TIFF.  This doesn't appear to be the Sony A7R3 problem.  
 
I use Capture One 10 (free) as my photo manager and because I use a Sony I have upgraded it to Capture One Pro 10, just a suggestion. 

Moonie, I was interested in your post so I have been looking at several things.  For example, if I simply Export an image out of Photos to my desktop, it exports correctly as a RAW file, but as you say, if you choose edit in Affinity from Photos, you get a TIFF.  I am wondering if Photos is doing the conversion before it reaches Affinity.  The TIFF file has filters applied when it gets to Affinity, while opening the RAW file that I exported to my desktop into AP comes in just as it should in the Develop persona.  They look remarkably different.  
 
I am wondering if this is an Apple Photos issue as I do not see how Affinity would applying any filters.   My thought is that they are not using the Master when the edit in is being used.  
 
When I am using Capture One, I use it to view the photos as it has a good catalogue system.  I mostly don't use 'edit in' with this software because it also produces a product that is no longer RAW, but it's sharpening feature is excellent, something that I use when I create Pano's in Affinity (Pano feature is awesome), so I am OK with TIFF files.    
 
I use Capture One because Affinity's Media Viewer is really slow and tedious, especially with the size of the RAW files that are produced by the Sony AR3.  When it gets better I will use AP's but for now, not so much.  

It is a normal and expected behaviour to use TIF format as transport format between raw developer and image editor. Photos expects you have done your developing in Photos and moving to AP to be just fine tuning. 

I am a Sony user, but with an ancient A55. I have never had any problems loading ARW files. If I understand what is being said then when @Moonie and @p_mac open one of these newer AWR files it opens 'as a tiff'. Does it not open in Develop persona? How do you know it is a tiff? Does it have a tiff suffix in the tab at the top?
I understand that the DNG format has some commonalities with tiff. I wonder if these newer Sony AWRs do this which is why the RAW engine recognizes it as a tiff.
John

As I understand it, there is a bug that affects the "Edit with..." command in Apple Photos when Affinity Photo is the chosen app. This may have other issues but one of them seems to be that RAW files are passed to AP as TIFF (or for some RAW filetypes as JPEGs) files in AP. 
 
To work around this, the following should pass the RAW file to Affinity Photo & open it in the Develop Persona:
 
1. In Apple Photos, double-click on the image so it zooms to the full size of the window & the "Edit" button appears.
2. Click the "Edit" button to open it in the Apple Photos edit mode.
3. Click on the "Extensions" button & choose "Edit in Affinity Photo." (Note that this 'edit in' option is phrased slightly differently from the 'edit with' option.)
4. The RAW file should now open in Affinity Photo's Develop Persona.
 
I am using version 3 of Apple Photos provided with High Sierra, so some of the details may be different if you are using an earlier version, but as long as you can get to the "Edit in Affinity Photo" option, it should work for you. Also note that like all other edits in Apple Photos, it is an 'all or nothing' process -- IOW, you can always revert to the original, unedited version but you can't revert to any intermediate edited version whether done in AP, Photos, or any other app.
 
Hope this helps.
 
EDIT: the "Edit with..." bug seems to affect all apps, not just Affinity Photo, so I guess this is an Apple bug they need to fix.

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