EXIF values in browser details and metadata panel are not consistent

[jkm]

XnViewMP is not displaying some metadata consistently in different places.

Look at the screenshot below.
In the metadata panel at the bottom, the aperture and shutter speed are correctly displayed.

But look in the columns (details view) of the browser... ShutterSpeed is empty (although Exposure Time is populated, so ok) and Aperture is completely missing.

If the app can display the value in one place (the panel) it should be able to show it in details view. So why is Aperture in the panel but not in the column?

This defect has consequences: because the APERTURE column is totally empty, you simply cannot sort by that value. That's a problem.

Ideally, if the app is incapable of automatically accommodating all the necessary variability of exif data for different cameras to deal with situations like this, there should be an area in the program where we can configure a manual mapping of exif tag values to XnViewMP metadata values; in other words, be able to specify the exif tag that corresponds to Aperture for XnViewMP, like we can do in the thumbnail labels configuration: {EXIF:F-Number}

Can this please be fixed?

[xnview]

please send us a sample file

[jkm]

I sent you a sample file by email.

[xnview]

Currently Aperture field is filled with Aperture field in EXIF metadata, so you would that if Aperture is missing, that we use Fnumber to compute it, right?

[jkm]

In my original post, I see that I wrote like many commonly think of f-stop and aperture as being the same. If someone asks "What aperture did you shoot that at?" you say "5.6". But actually in the world of EXIF, they are technically different.

I think the best solution would be to make Fnumber a sortable column.

Using the Fnumber value for Aperture would be incorrect, since they are two different things, and the values can be quite different.

Different camera manufacturers populate the fields differently, but according to the EXIF specification, we have this:
0x829d FNumber unsigned rational 1 The actual F-number(F-stop) of lens when the image was taken.

0x9202 ApertureValue unsigned rational 1 The actual aperture value of lens when the image was taken. To convert this value to ordinary F-number(F-stop), calculate this value's power of root 2 (=1.4142). For example, if value is '5', F-number is 1.4142^5 = F5.6.

Exiftool says that ApertureValue is displayed as an F number, but stored as an APEX value.

Technically ApertureVaule=LOGsqrt2(FStop) and then rounded. They are equal for some Fstop values, but not all. for f/4, Av=4; for f/2, Av=2, but for f/8, Av=6 and for f/11, Av=7
Canon follows that formula, so both FNumber and Aperture are populated in Canon files, but the values differ.

So copying the ApertureValue into FNumber without doing the correct mathematical conversion (if indeed the camera manufacturer implemented the tags correctly) would produce incorrect results.

As I said, being unable to sort by the Fnumber (which many think of as Aperture) is a problem.

The best thing would be to make FNumber a sortable column. That way the user can sort by the value available, no conversion is necessary, and the user is not deceived as to what values are populated.