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Photo Ninja help needed for metadata issues


Andy Perrin

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Andy Perrin

I'm still trying to figure out Photo Ninja, and in particular I would like to have the software correctly label my images with the metadata when I render them. In particular, since I'm using the camera in manual lens mode, the software does not know what lens or aperture I'm using, and I'd like to tell it somehow. Right now it is automatically adding 0mm aperture and F0 to every image unless I fix it by hand. The metadata says the lens is a "Sony E 35mm F1.8 OSS" instead of the actual lens I used, and the options for changing it seem to be limited, with no way to add additional lenses:

post-94-0-22942700-1457927275.jpg

 

Any suggestions? Thanks to anyone who has something to offer!

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Andy, I don't think that Photo Ninja has any EXIF editing capabilities. It can only read what the Sony's EXIF is. If the lens is declared "unknown" then I think you can add it. But I don't know how you would get the camera to do this.

 

There is an app called Exiftool (I think, I have to go check this) which can edit EXIF. It is a command line tool.

I'll get back to you after I've had a look.

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For some reason the main link to Exiftool is broken.

Here is the link to the Exiftool documentation: http://www.sno.phy.q...iftool_pod.html

 

I'll keep looking. Can't think why Phil Harvey would have a broken link!

 

 

Here we go: http://search.cpan.o...ExifTool-10.10/

 

And here is a little tutorial about adding a lens: http://hobography.net/en/exiftool-exif-manual-lens/

(scroll down)

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Here is an excerpt from the tutorial showing how to add lens info to the EXIF of a photo file. This will also overwrite any existing lens info.

*********************************************

Anyone new to this stuff, please do practice first on a copy of a photo file.

And make backups of any photo file to which you are going to apply EXIF changes before hitting them with Exiftool writes. You CAN contaminate a file if you make a mistake.

*********************************************

EDITOR'S NOTE: I DON'T THINK THIS TUTORIAL WORKS AT ALL!!!! I'm going to cross it out.

See Post #11 below.

 

You installed ExifTool and are now ready to execute your first command. In this example, I will tag photos for my New Petzval lens. Here is the info:

  • Lens name: Lomography Zenit New Petzval
  • Lens model: Lomography Zenit New Petzval
  • Focal length: 85 (do not mention the unit which is always in mm)
  • Maximum aperture number: 2.2

The command line will look like this (well, at least under OSX Terminal… I don’t know about Windows).

The input arguments are in bold.

An argument name is preceded by a '-' and followed by an '=' when the argument needs contains a value.

Argument values are in double quotes.

The command is all on one line even though it may appear wrapped here in the forum window.

 

exiftool -Lens="Lomography Zenit New Petzval" -LensModel="Lomography Zenit New Petzval" -FocalLength="85" -MaxApertureValue="2.2" -m -overwrite_original_in_place "Absolute/path/to/your/file"

 

If you want to edit several files, you can specify them one after the other, separating them with a whitespace. Like this:

 

exiftool -Lens="Lomography Zenit New Petzval" -LensModel="Lomography Zenit New Petzval" -FocalLength="85" -MaxApertureValue="2.2" -m -overwrite_original_in_place "Absolute/path/to/your/file1" "Absolute/path/to/your/file2" ...

 

Depending on your OS, the way to get the absolute path of a file is different. On OSX, you simply read the info (Cmd+I). On Windows, you can “copy as access path” in the right click menu. And if you’re on Linux… Well, you know better than me how to do this ;).

Easy, wasn’t it?

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Andy Perrin
Can I set it to "Unknown" with the EXIF tool, and add lenses to that drop-down menu in Photo Ninja? The way the menu is configured, it looks like it SHOULD be able to do that...
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I don't know! Try it and let us know if it works.

 

It might be that Photo Ninja only writes an added lens to the sidecar file and does not change the actual EXIF??

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Andy Perrin
That would be fine with me! What I really want here is some way to get Photo Ninja to make the automatic file names correct. Will report when I have some time.
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PhotoNinja is not very clever when it tries to identify a lens from the EXIF data. The main problem is that they believe the "closest lens metric" calculated from heavens know what data is infallible. Thus PN claims my lens marked in the metadata as '27 mm f/2.8 Nikkor' lens is a Zeiss 21 mm f/2.8 ZF.2 ???? I have no idea how such an error can be explained away. There are many similar cases and I don't look at the suggested ID any more because it is usually way off the target.

 

PN is an excellent RAW conversion programs in some fields, but very poor in others. It has no idea of file handling or digital asset management for that matter. Use something more appropriate for such tasks.

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As long as Photo Ninja converts well, I forgive it its deficiencies in dam, etc. :D I have other good apps for such things. And rather prefer that the functionality in apps stays a bit separate. Those one-app-does-all things like Lightroom always fail on some level to provide the workflow I want. I've always used the excellent Photo Mechanic for ingestion, file naming and sorting.

 

Anyway, for those handy with executing scripts from a command line, this Exiftool app is a nice easy way to permanently provide correct lens identification. If I were a more organized person (LOL!!!), I would run Exiftool after ingesting my photos and add correct lens info for all these unusual UV lenses we use. I just never have enough time to do things like that these days. Maybe if I hire a housekeeper.......

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Looked further into the Lens type issue in Exif because like everyone else I have some "unknown" lenses.

Turns out the whole thing is much more complex than I thought. (Life is always like that, eh??)

 

When I run Exiftool on one of my nef files to find out the lens type, I get the following output (for example).

 

Command: exiftool -LensID /path/filename

Output: AF-S Nikkor 70-200mm f/4G ED VR

 

But that output is NOT what is actually stored in the Nikon Exif.

Instead there are some identifying numbers which Exiftool is translating to produce this output.

Exiftool has a Nikon lens list which is used to correlate the actual Exif code to a Nikon lens.

 

That does not make it easy to update Exif with the actual lens used because, of course, the Exiftool list for Nikon does not include all the world's weird lenses. However the lens list is extensive!

Here is the Exiftool link to Nikon Exif: http://www.sno.phy.q...ames/Nikon.html

 

(Used Nikon in this discussion. Same conclusion holds for other brands.)

 

Now I'm looking at an Exiftool config file looks like it could permit adding lenses to the list. So stay tuned.

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Sometimes....I....hate.....forum.....software.

 

Bjørn, I just wrote you a nice long explanation about why LensTables used by various apps have difficulty determining what lens you are using.

Then somehow the forum software ate the whole thing because of some lag in the posting.

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The LensID tag is a composite made up of 8 different EXIF fields. Amongst these is a proprietary CPU code that Nikon uses to differentiate their own lenses.

 

It's easy to build your own ID routine based upon the LensID. Or to be precise, it would be, if all makers adhered to the same principle of feeding the data into these EXIF fields. However, they don't do this, surprise ??

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The various problems with Lens Tables are:

  • duplicated listings
    The Lens Tables have duplicate entries because those 8 Exif fields are not enough to uniquely identify all lenses.
    So we must blame Exif standards for not containing enough info I suppose.
    Exiftool offers a Config file so that you can indicate which lens you choose from the duplicated entries.

  • proprietary information
    Exiftool says they have decoded the Nikon proprietary lens data. Why Nikon would want to keep lens data proprietary I cannot fathom.

  • missing lenses because of an infinitude of lenses in general

One more problem is that some of the Lens tags are not writeable. Why I don't know. But it prevents correction of lens data which I had so hoped to implement myself.

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Andy Perrin
Yeah, I still have to play with the Exif tool and see if anything can be done. I'm hand-labeling the files now, and I got it to stop adding the wrong info by modifying the template for the name. It's really too bad the feature doesn't work the way it's supposed to, because it would be lovely if it labeled everything for me.
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