GPS Accuracy

[rcolman]

GPS in a dSLR is critically important to me. I photograph archaeological sites and location is really important. In fact, I bought a 6D just because of the built-in GPS.

I am not wild, however, about the accuracy. I am usually outdoors with a clear view of the sky, but still see that points wander about when they should be at a single point.

I wonder if the GP-E2 is more accurate and REPEATABLE than the built-in 6D GPS? 

Rick

[Skirball]

I don't know much about the GPS on the 6D.  I own one, but never turned it on.  But, just as a general comment - if accuracy is important to you, I'd really look into a separate GPS unit.  I'd guess the one in the 6D (and 70D, 7D2) is more a marketing feature than anything else.

I have a GPS for my bike, and a watch for running, and the accuracy isn't terrible good in that either.  I upload it to a website that then compares it to a map, and fits it to roads and trails as best it can.  But before that process there are certainly outliers.

My phone is better, because it triangulates with the cell towers.  But even then, sometimes Google maps thinks I'm driving 50 feet off the side of the freeway.

Again, I don't know too much about the specs of GPS, but I'm guessing that if you really need accuracy that you'll need more than a consumer GPS.

[rcolman]

Thank you very much for your comments,. They are appreciated. That said, however, there is  a HUGE difference in between using GPS on a bike ride versus being on the side of a cliff, 30 miles down a dirt road in the middle of nowhere.

Built-in camera GPS is a great advantage, both in the field an during image and data analysis. For example, how much fun would it be to manually geotag a couple of thousand images after the fact, hoping that something has not gone wrong?

Sony SLT cameras were among the first high quality DSLR cameras to offer built-in GPS and I owned three different bodies. GPS quality was reasonable, perhaps better than the 6D, but I moved away from Sony to Canon for other reasons.

However, the trend is away from built-in GPS, which is very sad. It is of great value to even casual users - most of whom say that they don't need without even trying it.

[hsbn]

I have the 6D and the GPS is terrible. It jumps all over the place, even if you just step back and forward a bit. I always have to drag the coordinate to the right location in Lightroom afterward. I'm mostly taking landscapes so I just need to know general area. But for your purpose, I think it is not good.

[TCampbell]

The GP-E2 is more accurate.   It is more sensitive and a bit more accurate than the GPS on the 6D and is also better at getting a fix in poor signal areas where the 6D may not be able to get a fix.  Also, it includes an electronic compass -- so in addition to recording latitude/longitude/altitude, it also reccords the magnetic direction the camera was facing when you took the shot (the 6D doesn't have a compass).  Lastly, it's also weather-sealed.

As I look at the map of photos I've taken with this GPS and then compare to where I know I was standing, the position fix is very close (within a few meters - which is about as good as typical GPS can get.)

KEEP IN MIND, however, that you get to set the update interval.  For battery saving purposes, you can configure the GPS to update every 1 sec, 5, 10, 15, 30, 1min, 2min, 5min intervals (you can save battery life by putting more time between intervals and also the GP-E2 has a "logging" mode and it can log longer with the less-frequent interval.)  THIS MEANS that suppose you set the GPS to a 30-sec update interval (which is what I use) and you talk several feet away then take a photo just before the next update interval, the GPS will not know that you've moved.  Both the 6D GPS and the GP-E2 GPS have those same update intervals.

I tend to arrive in a spot and then work with that spot for several minutes before moving on... so a 30 sec update interval is fine for me.  If you're moving around a lot... increase the update-interval.

[rcolman]

Tim, thank you. Do you know of any test data, informal or otherwise, comparing the units? I don want to spend another $300 unless I really need to do so ...

[MHampton]

I just really tried out the GPS on my 7DmII and when I checked the coordinates later, they were all over the place, even though I was shooting at a fixed location. All the photos were tagged within about a 3000ft area, but I was stationary with my tripod at a bird watering station.

[jrhoffman75]

You can get a Hoya data logger from Amazonfor under $100. It's returnable. It comes with software that will geotag your photos by using the HOS and camera time stamps. Try it for accuracy and if it doesn't work you can return it.

A DSLR with GPS is a photo tool that can give you a close approximation of where the photo was taken. Sounds like you really want and accurate GPS tool to locate a site and grap a photo of it. Different focus😀

[MHampton]

I have other GPS devices to do it the manual way. I was hoping that if Canon was going to put a GPS locator in the camera that it would be accurate. If not, why bother. It will just make people complain. As my father always said, "if you're going to do something, do it right."

[rcolman]

Not that simple. Remember the engineering Rule of Thirds - you can usually have two out of three: accurate, cheap, or reliable. It would not surprise me that the built-in is fairly accurate, but not reliable. Even larger and more sophisticated hand-held GPS units sometimes have a function that will average multiple readings to get one that is close ...

My BIG question, which no one seems to be able to answer, is if I spend money and hassle with a larger GP-E2 unit, will it be more accurate and reliable? and how much.