Eye-fi card question

Since the eye-fi does evidently have a limited range, if I am out of range for e.g. at a festival that has a press area that is passed the range of the wi-fi signal, if I suddenly get back into range, will it start syncing to my laptop automatically or do I have to do this manually? Or could I use the organiser's wi-fi network to ad-hoc their signal so I could sync with my computer?

Yup, as in the gear's list, I have the 5D3 with all the gubbins for eye-fi settings

You will need to take one photo once you get in range for the eyefi to start uploading the photos to your laptop.

Will there be any indicator to show whether I am in range?

Nope no indicator. You will need to do some experiment s to get the feel for its range. With the 1Dsmkiii I know I have about 15ft range from the laptop to the camera for good transfers after that it gets finicky.

Thanks

Unless the Eye-fi card has changed from how it functioned years ago, the wi-fi card has to be setup and 'paired' to a specific wi-fi network (ad hoc network or router accessed network) using Eye-fi's setup software (not while Eye-fi SD is installed in the camera), it does not merely opportunistically connect to the 'available wireless network' like you can do with a laptop or smartphone when going into Starbucks or Macdonald's free wifi network.

wilt you are correct, you will need to setup the eyefi with the specifics in terms of wireless network to be used or with device you will ad-hoc to.

I usually just use my ipad and just stick it in my messenger bag while I roam around during events. There are occasions that I will use my laptop if I am able to secure a location.

I've also tried the portable router route with a battery powered router, and transfers seem to be slower than direct ad hoc, more range, but slower transfer speeds.