Are the AF Coordinates stored in RAW files?

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I noticed recently that by clicking the "INFO" button on my E-PM2 when viewing photos, it seems to show where in the frame the AF was focusing.

I've googled this and can't find any info at all.

My question is: Does any PC software exist (eg. a Lightroom plugin maybe) that can read this data from the RAW files?

Looking at my Panasonic G3, I don't think it even does this at all - is it maybe only an Olympus thing?

Cheers!

Rob
 

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AF points are usually proprietary data that the camera manufacturers do not normally share with third party software developers. There may be a few exceptions, but Adobe does not have access to that data for Lightroom.

--Ken
 

NWright

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I've written some python code that allows me to access JPEG exif data.

When I get a chance I'll look into some of the raw exif output that I churn through with my code and see if any of it is tied to AF points.

Stay Tuned.....
 
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That's one of the things I missed when I switched from Aperture to LightRoom.
It's tempting, but I'm too heavily invested in Microsoft kit to switch to Apple at this current time. As a huge Unix/Linux-head it would be cool though. I spend a lot of my work day ssh'd into Linux servers that I use for number crunching, even though the box on my desk runs Win7.
 
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I've written some python code that allows me to access JPEG exif data.

When I get a chance I'll look into some of the raw exif output that I churn through with my code and see if any of it is tied to AF points.

Stay Tuned.....
That sounds intriguing. I've been meaning to try and learn Python for ages. My occasional scripts tend to be in Perl.
 
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AF points are usually proprietary data that the camera manufacturers do not normally share with third party software developers. There may be a few exceptions, but Adobe does not have access to that data for Lightroom.

--Ken
Thanks Ken - I often ponder why corporations make some info available and some not - like Panasonic bodies correcting CA with their lenses. I realise it's all a balance between supporting the overall m43 platform vs competitive advantage against "the other guy".

Rob
 

Replytoken

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It seems especially silly IMHO since most of the included raw converter software provided by manufacturers is horrible for any type of workflow and cataloging.

--Ken
 

NWright

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exiftool shows all those AF-field infos: http://www.sno.phy.queensu.ca/~phil/exiftool/
Maybe I'm just too dense..but could you be more specific about where in the documentation you see the tags related to the number of potential focus points, focus area used, ect...?

I see that from the above mentioned Lightroom Plugin at least some manufactures do include the focus point information in the exif data, but I'm having a hard time figuring out which tags, specifically, store that required information (FYI I am looking at Olympus's .ORF files)

Thanks!
 

kirschm

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Maybe I'm just too dense..but could you be more specific about where in the documentation you see the tags related to the number of potential focus points, focus area used, ect...?
I regularily use exiftool to analyse my RAWs. You find for example at least 2 focus field related infos... : AFAreas, AFPointSelected

You can even see this info in the exiftoolgui.exe:
Subscribe to see EXIF info for this image (if available)



This is for example the command that I use to get my most important exif infos (alternative to the exiftoolgui.exe):
c:\Progs\exiftool\exiftool.exe -r -csv -Directory -FileName -fileType -DateTimeOriginal -CameraID -model -LensType -lens -LightValue -ISO -Aperture -ExposureTime -FocalLength -FocusDistance -DOF -ImageStabilization -ExposureCompensation -ExposureMode -ExposureProgram -ExposureShift -Flash -FlashControlMode -FlashExposureComp -FlashFirmwareVersion -FlashMode -FocalLength35efl -AFAreas -AFPointSelected -AFSearch -AspectFrame -AspectRatio -BodyFirmwareVersion -CameraType2 -CircleOfConfusion -CompressionFactor -Contrast -ContrastSetting -CropHeight -CropLeft -CropTop -CropWidth -CustomSaturation -FaceDetectFrameCrop -FaceDetectFrameSize -FacesDetected -FileSize -FileType -FNumber -FocusMode -FocusProcess -FocusStepCount -GainControl -HyperfocalDistance -ImageDescription -ImageHeight -ImageWidth -InternalSerialNumber -LensSerialNumber -MaxApertureAtCurrentFocal -MaxApertureAtMaxFocal -MaxApertureAtMinFocal -MaxFocalLength -MinFocalLength -MeteringMode -ModifyDate -NoiseFilter -NoiseReduction2 -Orientation -PictureMode -PictureModeSaturation -PictureModeSharpness -Saturation -ScaleFactor35efl -SceneCaptureType -SceneMode -SensorTemperature -SerialNumber -Sharpness -SharpnessSetting -ShutterSpeed -Software -Warning . > d:\adhocNoBackup2\MK_exiftool_BestimmteFelder_CSV.csv

And this is my command to get all exif info: c:\Progs\exiftool\exiftool.exe -r -csv . > MK_exiftool_BestimmteFelder_CSV.csv
 
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Thanks guys, that's brilliant!

So I've had a quick play with ExiftoolGUI tonight.

It seems that the position info encoding is similar in Panasonic .RW2 and Olympus .ORF files.
In both cases the coordinate origin is the top left corner of the picture.
In both cases the values are reported as x (across) and y (down) - I only tested landscape orientation, mind you...
For Panasonic, the parameter is "AFPointPosition" and is given as a pair of number between 0 and 1 (eg. 0.5, 0.5)
For Olympus, the parameter is "AFPointSelected" and is given as a pair of percentages (eg. 50%, 50%)

I've not worked out what the other parameters mean yet.
I did discover that deliberately setting the focus point on my G3 that I've had for 2 years was a bit of a pain.
...whereas setting focus point on my E-PM2 that I've only had a few months was quite easy.
Even though overall I think the Panasonic GUI / controls are more intuitive than the Olympus ones.
But I digress.

Thanks all for your engagement in this rather nerdy topic!!!

Rob
 
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