What is the correct geolication?

[Paul Barrett]

Q. What is the correct geolocation for a photo, the position of the camera or the subject?

They may be quite different. For example if I take a photo of a mountain I may be miles away,

I think it has to be the subject's location but GPS enabled cameras will make it the camera's location. I can easily tweak it in Daminion of course.

 

Am I making too much of this? Should I accept the inevitable - that GPS enabled cameras will win the battle?

Thoughts?

Regards

Paul

[Uwe]

Hello Paul,

it's your decision who wins the "battle". Sure, you are not in the winner position if the object is responsible for the geo data. I think, you don't position a GPS receiver on the object position, miles away ;-)

In the most cases the object and the camera are nearly at the same position. The really difference for me are "rounding errors". What do you want to do if you take a photo of the earth in an airplan? Do you want to consider also the altitude - of the airplane or of the object on earth?

If I'm really interested in having the right GPS data of the object I have to enter them manually - but I don't do it.

Regards, Uwe

[Paul Barrett]

Good point Uwe.

 

I asked the same question on the ExifTool Forum and received some interesting information. Stargeek said:

"The exif standard has two sets of gps locations. See GPS tags, tags ids 1-6 and 13-1a. Unfortunately, it seems that the EXIF spec doesn't clearly state which tags to be used for what purpose. But the Metadata Working Group Guidelines For Handling Image Metadata (location section starts pg 45) says that tags 1-6 are for the location created and 13-19 are location shown.

 

My opinion is that it should be the location created so you can go back to the same spot to see the same scene later, to try and recreate the shot if you would like to. If you were to put in the location of the subject only, that would be extremely imprecise. If the subject was a mountain and you put that as the location, then it would be extremely hard to duplicate that shot, because the location could be any number of miles away in any direction.

Additionally, the subject of the photo could be very subjective. While you may be taking a picture of your friend Bob, someone else might focus Godzilla emerging from the volcano erupting in the distance and yet another person might think it should be Chuck Norris beating on ninjas 50 feet away on the right. All three worthy subjects but at very different locations."

And Phil Harvey (creator of ExifTool) said:

"Actually, the new IPTC for XMP extension adds GPS tags for both LocationCreated and LocationShown. Presumably the former is for the camera and the latter is the subject."

Based on those facts (that there are specific tags for camera and subject locations) it would be interesting to get Daminion's views on what they might do to support this.

But you're right Uwe, there is manual work to be done. I am doing that right now, which was what caused me to ask the question.

As things stand right now, it looks like the decision on what geolocation to use is subjective and rests with the image owner.

- Paul

[lintujuh]

Hi

 

I'm using the geolocation for "LocationCreated". Exactly for the same reason as Paul cited Stargeek – to be able to recreate the shot.

 

-Juha

[WilfriedB]

Same as Juha and Stargeek, I believe "LocationCreated" makes more sense - at least for to start with. In rare cases ("What is the name of the mountain in the background?"), I add the direction and distance to the subject manually using GeoSetter, which unfortunately cannot be displayed in Damion (or does it??). But usually this defines a point in the center of the picture, which may or may not be the main subject as Stargeek pointed out clearly.

But the same question comes up for "place" metadata in text. Based on the GPS coordinates of the camera position, I create the Country, State/Province, City, Sublocation set of Tags (again, using GeoSetter).

Here, I agree with Paul, it makes more sense to refer to the subject, but this requires much more manual work. For now, I decided for "Country, State/Province, City, Sublocation" to describe the camera position, mainly because GeoSeter does it automatically, (except for Sublocation). In addition, I may (or may not) add hierarchic keywords, if the picture mainly shows a place different from my position. For example, I was standing in "Italia/Umbria/Spoleto/via Vaita San Andrea" making a picture of Via Filippo Marignoli the additional keyword would be "@Via\Filippo Marignoli" (the leading "@" to place those at the beginning of all keywords).

[Paul Barrett]

Thanks Wilfried

 

Another perspective added, and it seems to be supporting the view that this is a very subjective issue.

 

Please keep the comments coming folks - I am fascinated to see different perspectives.

 

- Paul

[WilfriedB]

Another point, I forgot to mention:

If you repeatedly make pictures of the same big subject (mountain, monument ... etc), you might want to group all you made at different times from the same perspective (e. "Notre-Dame-de-Paris" from "Square Jean XXIII"). This also asks for storing both positions.

But in general, I am still struggling organizing all the shots in big cities, I often visited.

Btw., I gave up with GPS enabled cameras and prefer to use a separate tracking device now (Android app Locus or Holux GPSStart).

[Paul Barrett]

For people who are not interested in geotagging this whole subject is uninteresting. But for those of who want to geotag there's a hell of a lot of manual work we have to do to satisfy our cravings. :)

 

So it seems to me Wilfried that what we need in Daminion is two 'Place' tags; one for camera location and one for subject location.

 

And to reduce the manual tasks we need to be able to assign a geotag to each of these locations and have Daminion do the following:

 

1. When a new camera location geotag is the same as an existing one, apply the same camera location tags automatically
2. When a new subject location geotag is the same as an existing one apply the same subject location tags automatically
3. And then we need the reverse of those two i.e. When we apply a camera or subject location tag to a new image, the geotag should be set automatically (perhaps with a warning if the new coordinates are very different)
4. And if we use Map View to visualise our geolocations we need a filter to differentiate subject and location locations, perhaps with a different coloured locator pin?
5. And is there any value in having subject location default to camera location from where it could be adjusted? (To minimise manual work.)

Just to add an extra complication, I use Synology Photo Station and it only supports Keyword Tags, none of the Place Tags. So I need to relate my geotags to keywords not places. (Of course, none of that would be necessary if Daminion was available as a Synology package - but that's another hobby horse of mine - for another time)

 

- Paul