Focus/Auto Focus Regions Not Correct

[Eric Mercer]

Why does the Focus/Show Autofocus Regions not correspond to the right position?  I have checked my focus point in Canons Digital Photo Professional V4 and it's way out on Affinity Photo.  What is the point putting it on the program if it isn't correct!  Surely this is a problem with the program which needs addressing in the next upgrade!

[Tom Lachecki]

The autofocus-region information is provided by the camera's metadata embedded within the image. It could be that we're parsing it incorrectly for your camera model.

Would you be able to post an example RAW file and an indication of what AF regions you'd expect to see instead?

Thanks!

[Eric Mercer]

I enclose two screen grabs of the image in DPP4 and also in Affinity Photo.  My camera was a Canon RP with EF 24-105mm f4 lens.  As you will see the two focus points do not correspond.

 

[Old Bruce]

As well, the affinity version is cropped quite a bit compared to the DPP version.

[walt.farrell]

8 minutes ago, Old Bruce said:

As well, the affinity version is cropped quite a bit compared to the DPP version.

Possibly a Lens Correction issue.

[Ron P.]

I wouldn't get too worried with those focus points in display Even LR requires a plugin to see them, and they are not all that accurate. On top of that you need to read them correctly. Red means the camera did not obtain locked AUTO FOCUS, Green=AUTO FOCUS LOCKED. Add to that, are you shooting Canon lenses or some other like Sigma, Tokina, ect. I never could use DPP, because I didn't shoot Canon lenses with my Canon camera.

When Serif first added this feature to AP, there were numerous times the focus points reflected in LR, did not correspond to AP. I learned quickly to ignore this gimmick. You can pixel-peep and pull your hair out trying to figure out why. Just because your camera locks focus at a small area, does not mean your image will be crisp and sharp. AF lock does not counter camera shake. 

[IanSG]

On 9/16/2021 at 7:53 PM, Eric Mercer said:

Surely this is a problem with the program which needs addressing in the next upgrade!

I had a play with this feature a while back and found some problems with it.  On reflection I couldn't see why I'd need it so I dismissed it as a gimmick.  What makes it so useful?

[NotMyFault]

The only use of this feature is to find the where the camera body thinks the focus should be (focus indicator) versus the lens ability to move the focus element into that position. I have tons of images where the image focus (area with sharpest pixels based on depth of field) do not match the focus indicator - even for in-camera or DPP images.

Possible reasons include

• slow focus motor
• misaligned lenses (no micro adjustment, no more relevant for mirrorless / live view)
• moving objects / camera and slow shutter speeds 
• 3rd party lenses

[R C-R]

13 hours ago, NotMyFault said:

The only use of this feature is to find the where the camera body thinks the focus should be (focus indicator) versus the lens ability to move the focus element into that position.

So it is really only useful for deciding if your camera's focusing ability or how you use it is being done correctly?