Question re GPS and geotagging

Bob W pdml at web-options.com
Tue Oct 13 03:50:53 EDT 2009


> I thought it 
> would be nice to be able to capture coordinates and roll them 
> into the exif files so that I could look at an image in LR 
> and see where it was shot. [This notion is based on my 
> frustration in sorting through images I had taken in Northern 
> Italy: now in which small fishing village was this harbor shot taken?]
> 

You could always do it the old-fashioned way and write it down in a
notebook.

[...]
> I could find no way on my Mac or a borrowed PC to change the 
> basemap, I found no resources for a base map of Costa Rica. I 
> generated some log files but had no way to export them to my 
> Mac. 

Why do you need a basemap in the GPS itself? I have a very basic Garmin
eTrex H which doesn't support basemaps. To plot routes I use Gmap Pedometer,
which is web-based and free. I load the the routes onto the GPS using
EasyGPS, which is basic and free. When you have been somewhere with the GPS
switched on you can download the tracks as .gpx files and use ExpertGPS to
plot the tracks on Google Maps. ExpertGPS is the more sophisticated
paid-for-but-still-very-cheap version of EasyGPS. Not sure if it supports
Mac - have a dig around: <http://www.topografix.com/>.

> I sold the Garmin on eBay at a small loss, bought a 
> notebook and pen. 

Aha!

[...]

> roadmaps and topo maps so I don't really need a GPS except 
> when traveling out of the country, and then more for this 
> sort of record keeping than for route finding.

I'm no expert on these things, but I think you can use even the simplest of
GPSes to record you current location and export it as noted above. Google
tells me that there is a program for Macs called GPSBabel which you can use
to export tracks from a GPS.

> But as Doug 
> noted, if one needs to have yet another battery enabled 
> device, it might as well serve multiple purposes.
> 
> Can any of you tell me if there is a unit/system that meets 
> the following critera?
> a. Mac compatible software for the GPS management b. Handheld 
> unit c. Simple changeout of the relevant basemap for a region 
> d. Availability of reasonably detailed basemaps for most/all 
> regions of the world.
> e. Simple export of log files.
> f. Reasonable accuracy, quick startup and signal acquisition 
> g. At least 16-hour battery life or easily interchangeable 
> batteries h. Simple (Mac compatible) software to synch log 
> files with exif data.
> 
> Oh, and of course low cost.
> 

There's the rub... Basemaps alone are hideously expensive. When I was
playing around before buying my GPS I used a number of free trial maps, and
was deeply unimpressed by them, and found the online resources much more
useable and useful.

I did note that the Satmap Active10 has a very good reputation, but it is
very expensive.
<http://www.stanfords.co.uk/stock/satmap-active10-162665/>

I'm coming to the conclusion that GPSes are becoming another of the devices
that seem like a good idea, but just end up overcomplicating our lives. For
me the eTrex H is ideal. I can fit it to the handlebars of my bike so I
don't have to keep getting off to check a map; it will tell me where I am if
I'm lost, and where I've been when I find myself again, and if I really need
that much accuracy on my photos I can probably find some freeware to match
the tracks against the exif data.

This page includes some links to software that links GPS tracks and exif
data:
<http://macdevcenter.com/pub/a/mac/2004/06/15/gps_photo.html>

However, is that much accuracy really necessary? GPS locations on the UK
grid are to 10 places, which is theoretically accurate to about a 1-metre
square, I think, but since the allowable variance on the device is well
outside that you're not really going to be able to trust the reference to
that level. If you're a scientist plotting the position of rare orchids that
you're photographing you're probably not going to be more accurate than a
few square metres anyway. So if it's just a means of remembering which
fishing village you were in on a given date, isn't this all overkill anyway?

>  
> stan





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