Is there a way to show the focal points on an image in RawTherapee? Looking to see the many focal points with the used one highlighted.
Thanks
I doubt it. I believe this facility is only available when using the OEM software to view the images.
I remember reading about focus points wrt darktable. Maybe it was just a feature request…
@SanchoSackville Welcome to the forum btw!
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This was on my todo list a while (some years) ago. But there have been more urgent issues to be solved.
That doesn’t mean that I’m not interested in that anymore.
Maybe we should start a new run to implement the focus indicators. I know that feature only from PhotoMe.
In case someone has documentation about the concerning exif data, that would be very welcome.
Ingo
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As @afre said, Darktable has such a feature but as far as I know, it shows focus areas detected by software rather than focal points embedded in the file by the camera. Its default shortcut is Ctrl+z in Lighttable mode.
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https://www.darktable.org/usermanual/ch02.html.php talks about the detected in-focus/sharp areas.
The camera focus point is different – that point may actually be out-of-focus, if the auto-focus failed or there was movement etc. It’d be great to have something like this in darktable.
GitHub - musselwhizzle/Focus-Points: Plugin for Lightroom to show which focus point was active in the camera when a photo was taken is a Lightroom plugin that does this, seems to get exif data like this: Focus-Points/CanonDelegates.lua at master · musselwhizzle/Focus-Points · GitHub
I’ve got the warning for reviving this topic yet I think it worth the try.
I found some info on the EXIF data concerning focus points. Truth is that from two different top line cameras I’ve got different results depending on the manufacturer. I will show 3 different examples where 4 should appear but I am pretty sure that in the forth case (an AF lens and not a MF one) for the same vendor things are dependent on the last one and not on the lens. Specifically:
Using PhotoME exif viewer I found that for Canon in the Manufacturer notes there is a section for displaying the focus point matrix (in a shown top right) that I suppose depicts the center point of the focus point and its area of depiction (171x169). That is for someone to display graphically all the points (Canon 1DX has 61 of them). This is an assumption not a fact.
Next it is noted that four points where used to focus (I use AI Servo with AutoFocus all 61 selectable points, back button focus). One can see that the programmer of PhotoME went one step further and implemented those focus points on the actual picture. Last entry shows that all 61 points are selectable I suppose.
In contrast in the next picture where I focused and recomposed without holding the back button for continuous focusing there are no AF Point(s) in Focus.
In the last example the EXIF info are from a different camera and in the same area where description on the AF Points exist there are none…
This picture is with a ManualFocus lens but as I mentioned in the beginning this is irrelevant (I have had also switched the camera to manual focus mode when the picture was taken).
I do not know if all that stuff helped, but it might be wise for other people to post info about their camera in that area from their exif data.
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IMHO the ability to display focus points would be a nice and useful feature to have in RT.
I have four different camera bodies available, all Canon: 400D, 50D, 7D2, 6D.
All these have focus point info available in exif in a manner similar to the 1DX.
The data describes an array of available focus points in phase detect mode (the classical SLR through-the-viewfinder AF) and enumerates the AF points that are selected to be active as well as those that achieved focus.
There are slight differences, the indices of the focus points in the 1DX data appear to start at 1, while those on all four cameras I’ve checked appear to start at 0.
Also, the 1DX has one single array of data that describes position and size of focus points, whereas the 400D, 50D, 7D2 and 6D define position and size of the focus points in four separate arrays - xpos, ypos, width, height. The 400D has some tiny quirks of its own, the 50D, 7D2 and 6D appear entirely consistent between them.
I managed to whip up a little script that uses exiftool to extract the data and produces a PNG overlay of the focus points with the active/in focus points highlighted, it works flawlessly for the the latter three with any image I tried so far. Getting it to work with the 400D will require a minor tweak.
So far, I haven’t considered Live View AF which is available on the 50D, 7D2 and 6D because I hardly ever use it, I’d have to shoot some test images for the purpose.
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Today I installed the digiKam open source software and found out in the metadata that for the same picture with the focus points it actually starts from 0 and ends up in 60.
I suppose that in this software that I used for finding out exif data (PhotoME), the programmer has made this change to present the data more pleasing to the eye of the user.
As regards PhotoMe, it appears that the software is quite old and no longer updated, the current (last) version is from 2009. Which is a bit of a pity because I like the combination of features it offers.
However, extraction and interpretation of exif data requires up-to-date software because manufacturer’s data changes and expands with every new camera model.
For inspection of exif data I’d suggest ExifToolGui, which looks quite similar to PhotoMe but its scope is limited to exif data extraction. As the name suggests, it’s just a graphical front end for Phil Harvey’s exiftool, which is probably the best and most up to date exif manipulation software available.
Also, the exiftool website has extensive lists of available exif data tags for most camera models, see here for an example.
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