This is my experience with geotag, I hope it will help someone.
As always, I test out my equipment before of my projects. I am using a GPSmap 60cx, an Oregon 450, a Canon D10 and a Nikon D3000. In the test, I had no problem. I started out the project. I flew to Mexico from Toronto. In Mexico, I synchronized the date and time between the GPSs and the cameras. I turned on the GPSs and took my pictures with my cameras.
Now, I am back in Toronto. I geotagged the pictures with BaseCamp. I checked the data with BaseCamp and MapSource. I was staring at pictures and the map for half a day. The tracks on the two GPSs are the same. The time stamps on the pictures from both cameras are close. Yet, all the data are wrong. At the end, I was luck that I had some reference points and discovered that all the data are an hour off.
So experts, where did I get wrong? What is the correct procedure?