PL4 requires manual focus distance entry while PL3 didn't

The help text is not clear on this topic, but … I’m pretty sure that focus distance is required only when an Optics Module does NOT exist for the {body+lens} combo … in which case, it’s used to assist with distortion corrections, etc.

Regards, John M

Not really - without an optics module the software does not require focus distance, as there is nothing it can do with this info. It is when an optics module is available, and when the EXIF does not report the focus distance, that a manual entering is required to fine-tune the optical corrections.

The Sony 24-105 f4 gives an accurate reading of the focus distance in the EXIF, so the software should use it. This is what PL 3.3.4 does (focus distance is greyed out as it should) but PL 4.1.1 doesn’t, and produces corrections that appear a bit random. So this definitely looks like a bug in PL4 Mac (the windows version appears OK, see above).

I’m now really intrigued, Julien !

I’ve never paid any attention to this correction before, as I didn’t think it had any relevance when an Optics Module is available - but now I’m not so sure (?)

But, I do now understand what’s meant by this;


I have 4 different camera bodies, but for only one of them (my excellent little Sony RX100 iv) does the Focusing Distance correction appear (in the Geometry group) … I’m on Win10 - whereas, I understand this always appears on the Mac version … which is probably why you’re noticing this, whereas I’m not.

The fact that it does NOT appear for some bodies (which, presumably, write to the EXIF data the focus info needed by PL) suggests to me that DxO does not consider it necessary for us to fine-tune this info for these cases.

@sgospodarenko/Svetlana: Could you please clarify this for us - That is; in what circumstances, if any, do we need to be concerned about providing Focusing Distance details ?

Also, note Julien’s observation here;

John M

The snippet about the focus distance sliders that you posted makes me even more confused! I have a hard time to figure out why the Mac and Win versions should differ on this point - if the info is there then the software should use it regardless of the platform?

Agreed - but the “interesting” part is that if it’s found in the EXIF data then it’s not displayed at all (in the Win version) … which implies that DxO does not consider it necessary for us to fine-tune this info (?).

Let’s wait for Svetlana to elaborate on this for us.

Meanwhile: I experimented with some images from my Sony RX100 iv - for which the Focus Distance correction is revealed (rather than being hidden - which it is for all my other camera bodies). I manually changed the focus distance - which resulted in different distortion correction results (from the default of assumed infinity).

John M

Hello everybody,

I wish you a happy New Year :slight_smile:

Let me clarify a bit this question of focus.

  • The Sony FE 24-105mm F4: in early December we modified DxO Optics Modules for this lens because some configuration of Focal/Focus were not well corrected in distortion. Before the modification the focusing distance was considered as non inlfuent on the distortion correction (focus min to max would end up with same default for the same focal). The correction showed it was wrong.

  • Focusing distance in Sony cameras: for a long time we didn’t get the focusing distance in Exif on Sony cameras. Now we do but Exif reading Sony A7 III has not been modified yet so Optics modules will still consider we don’t read it. It will be modified later.

  • Focus slider: There is an ambiguous focusing distance when slider “focusing distance” is available in pannel “Geometry”. This slider is present or absent for all images made with same couple camera + lens.
    If there focusing distance isn’t declared as ambiguous in module then slider won’t be present for Windows and will be grayed out for Mac.


    so when focus slider is present and usable it means that the focusing disance you set with it well have an impact on distortion correction (sometimes it wont as maybe focus has influence for some focal but not all). By default focus distance is set to max value, as it is the most common one.

  • Focus values: inifinty value we can have in Exif has evolved through years that’s why you can have 40 or 128 for some lenses we did support some years ago.

I hope it’s clearer now.

Regards,
Marie

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Thanks a lot for the clarification Marie and happy new year,

Still I believe there is a problem. Following your algorithm chart for the Sony 24-105, the slider should be grayed out (Mac) or absent (PC) as this lens writes a ‘Focus Distance 2’ entry in the exif which looks very accurate to me. The camera I use is an A7RII (not an A7III).

Thanks,
julien

I have a Panasonic Lumix GX9 and with v4 (on a Macbook running Catalina) I see “Focusing Distance” which I didn’t notice with v3 (but maybe it was there and I just didn’t see it?). Regardless of lens and actual distance it shows me a range of more than 40.00m, the distance sometimes being 60m, sometimes 128m, even if the focus point is 2 meters away from my camera. That looks quite mysterious to me. If I correct the distance by hand I don’t really see a difference in the distortion correction. I should add that all relevant optics modules are loaded.
Using exiftool I don’t see an item “focusing distance” in the output.

Thank you for the explanation, Marie - - that’s much clearer now.

Was this announced anywhere - perhaps in update release notes ? … It’s useful to have such info, so that we can re-process images taken with this lens.

When it is, can this please be announced - so that we can go back and re-process images from this lens.

Yes, I can confirm this with images taken with my little Sony RX100 (iv) … In this case, the Focus Distance is made available for manual entry - and I can see this reflected in the degree of distortion correction that’s applied for different manually entered values.

For my Sony a7 III, I identified FocusDistance2 as the likely EXIF value for Focus Distance (as, I see, Julien did too). It does reflect some “strange” values, tho … for subjects quite close to the lens it seems to be accurate … but, for subjects far away it shows values such as “222”, “248” etc !!

Regards, John M

Yes, I guessed that FocusDistance2 might be subject distance too, Julien (as revealed using EXIFtooGUI) - but it’s showing some strange values for me … See my comment to Marie, above.

It won’t necessarily be labelled that clearly, Rainer - - eg;

  • It’s clear for Olympus: image

  • But I’m just guessing for Sony: image … 248 meters, perhaps ?

John

Hello,

It was’nt.
We have some improvement to do about new lens support and updates. I’ll discuss that with Captain PO.

Focusing distance is in ‘Focus Distance 2’ entry (which is a calculation, not a real tag) but we don’t use it for now on this camera.
When we will use it we will announce it.

Infinity is usually something after 3m or 5m in photography. Years ago max focus value in Exif was recorded as 40m then 128m. So these values can still be used for lenses supported years ago. For Sony you have to know that FocusDistance2 is not a value recorded by the camera/lens in Exif but a calculation done by ExifTool. We do it to but so for high values accuracy is not perfect but it doesn’t have any influence as I said, after 5m it’s like infinity.

Regards,
Marie

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Thanks Marie. This is an interesting thread, I’m learning things here :slight_smile: For now I’m happy with the replies, as I am assured that PL4 will do a better job correcting the 24-105 provided a sound focus distance is manually entered.

Piping the output of exiftool through “grep ocus” I find “Focus step near” and Focus step count", possibly the program tries to calculate the distance from these data but gets it dramatically wrong (128.00m for a closeup macro shot with my Lumix GX9 and the Leica DG Elmarit 45mm, with focus step near =0, focus step count = 34 as an example).
Anyway, what I would really like to know: Will this wrong focus distance actually deliver bad corrections, i.e., do I have to look at the photo, try to guess the distance at which it was shot and correct the value in order to get optimal results?

Thank you, again, Marie … 'tis excellent to get this info straight from the expert … :+1:

John

In PL5 I always get the focusing distance palette active, with any camera and any lens, whether they are in the dxo database or not. Is it because I focus in manual mode with the assistance of the rear AF-L button? I use several Fuji, but with Canon I did it the same way.
Anyway I don’t understand its usefulness. I only see that it changes the framing a little bit…

The correct focus distance determines the proper application of the lens distortion correction parameters. If it is not present in the EXIF, it must be entered manually.

As far as I know the lens distortion depends on the focal lenght. It is true that macro lenses change a little bit the focal lenght when one focus very close, but I guess I would say that it is virtually irrelevant with the vast majority of lenses. Am I wrong?

I am have s Sony a6000 and a64000 with most lenses not working. There is a big effect on ones like the 70-350. I also have found some majer changes with a Sony 90mm macro.I had raised this today on some Sony fourms and that the A range is not fully supported in PLs going down well!

Added

Some time ago focusing distance was removed from many Sony a lenses. Back in 2020 Marie said this will be raised with Captain PO is there any progress. I ask as with my 90mm macro the distance makes a lot of difference on the image and with a day’s work it’s a pain having to work out what distance to change a lot of images. To make it worse we learnt there wasn’t a problem in the Mac version of PL.

The result of this appears that new E modules are need on Version 3 of the program that removes the automatic distance correction in that version (and probably earlier ones as well). My wife’s very occasionally used V3 now needs to download all the existing Sony E lenses modules which remove the automatic distance correction which was present on the old ones, thank for progress!