I use this unit on my D7100 mounted on the hotshoe. The cable attaches to a side port. It sometimes takes a few seconds (up to about 30, depending on conditions) to acquire a satellite lock but once it does I've found it to be extremely accurate. Surprisingly it seems to have no issues acquiring a lock indoors in my home (single level).
GPS should come internal to the camera but the fact that it doesn't isn't a fault of this unit, it functions as designed. I've mounted it on the camera strap before and it worked well there, too. The cable is stiff and doesn't flop around. Give this unit decent care as you do your multi-thousand dollar camera and lenses and it should serve you well.
I just finished a 15 day “field test” of the GP-1A GPS on my D-600.
I was very disappointed in the performance I received from the GP-1A unit.
To minimize some of the damage potential mentioned in another review I mounted the unit on the camera strap, then coiled and “twist-tied” the excess GP1-CA90 connecting cable. This worked okay but the GP-1A unit would bump up against my forehead while shooting. Eventually I became accustomed to this annoyance.
To enhance battery life while hiking I did not leave the camera full time in the “On” position. However I did always turn the camera on several minutes in advance of shooting. Frequently, even after five minutes or more, the GPS unit never acquired the necessary satellite signals and continued to Blink Red. Occasionally it would show Solid Green for a few seconds and then revert to Blinking Red.
While hiking it was almost impossible to get Solid Green.
After 15 days and 1,648 photos taken on the D600 with the GP-1A GPS attached my results were 966 images (~60%) geotagged (as shown by Places in Aperture 3). All but seven of the photos geotagged appeared to in the correct location. The locations referenced in the seven errors were all off by more than 100 miles each.
So how does the Nikon unit stack up to others? I also had along a recent model unnamed “point and shoot” camera (approximate camera cost of $390) with an internal GPS. As with my Nikon D600 I did not leave the camera in the “On” position – but turned it on prior to use. Of the 935 photos taken with this camera 837 (~90%) were properly geotagged.
In addition my wife and I both had our smart phones with us. My wife took 498 photos of which 493 (~99%) were properly geotagged, and I took 49 photos of which all 49 (100%) were properly geotagged. The phones were left on between shoots.
I have been an avid and loyal Nikon user since 1971. I like others enjoy geotagging photos. In my opinion the GP-1A GPS is not ready for sale. But for a loyal Nikon customer that wants to geotag, what other option do I have?
Has the same cable as GP-1. Will have damage to the connector or worse to the camera port as with my D7000. I do a lot of travel and is a great feature to have the geotags on the photos but not at the expense of having your camera damaged due to a bump on a busy street or tourist attraction. I will not use this on my D600 until there is a new cable design!!