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musselwhizzle / Focus-Points

Plugin for Lightroom to show which focus point was active in the camera when a photo was taken
Apache License 2.0
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Slight differences of the focus points displayed in the plugin and the built-in camera screen #176

Closed lethal233 closed 11 months ago

lethal233 commented 11 months ago

Hi,

Firstly I want to say thanks to your dedicated developers. After successfully installing the plug-in, I saw a slight difference of the focus points displayed in the plugin pop-up and the built-in camera screen. I was just wondering whether this can be accepted or not. If it cannot be accepted, is following the "add your own camera" section the next step?

Camera Model: Sony Alpha 7 C II

Your plugin shows: image

The built-in screen shows: IMG_9809

capricorn8 commented 11 months ago

I don't have Sony specific AF knowledge, but the following applies to modern mirrorless cameras in general and should be kept in mind when evaluating the plugin result:

  1. The plugin relies on documented tags from EXIF metadata (maker notes section) to retrieve AF information. If the camera does not maintain these fields properly because it primarily uses other AF related sections in an undocumented part of maker notes the results of camera (or maker's RAW converter) display and plugin may differ. I am using OM-1 and can see a similar behavior. For OM-1 predecessors E-M1, E-M5, E-M10 results are identical.

There are other Sony AF visualizers eg. https://github.com/SK-Hardwired/s_afv. You might want to check if these show differences in AF position as well.

  1. For cameras using contrast AF, the center dot displayed by the plugin is misleading*. The focus point is somewhere inside the red box. Accordingly, on camera display the focus point is somewhere inside the green box. Both red and green boxes in the images do overlap, so in my opinion the difference is acceptable.

*That's why I have removed the center dot for Olympus and OM System cameras. I am neither the inventor/author of the plugin nor do I have specific knowledge about Canon/Nikon/Sony etc. so I didn't want to touch the logic for other camera makers.

lethal233 commented 11 months ago

I don't have Sony specific AF knowledge, but the following applies to modern mirrorless cameras in general and should be kept in mind when evaluating the plugin result:

  1. The plugin relies on documented tags from EXIF metadata (maker notes section) to retrieve AF information. If the camera does not maintain these fields properly because it primarily uses other AF related sections in an undocumented part of maker notes the results of camera (or maker's RAW converter) display and plugin may differ. I am using OM-1 and can see a similar behavior. For OM-1 predecessors E-M1, E-M5, E-M10 results are identical.

There are other Sony AF visualizers eg. https://github.com/SK-Hardwired/s_afv. You might want to check if these show differences in AF position as well.

  1. For cameras using contrast AF, the center dot displayed by the plugin is misleading*. The focus point is somewhere inside the red box. Accordingly, on camera display the focus point is somewhere inside the green box. Both red and green boxes in the images do overlap, so in my opinion the difference is acceptable.

*That's why I have removed the center dot for Olympus and OM System cameras. I am neither the inventor/author of the plugin nor do I have specific knowledge about Canon/Nikon/Sony etc. so I didn't want to touch the logic for other camera makers.

Gotcha, thank you very much! I will try the visualizer instead.