Is someone filming you or do you have your camera on a tripod? and how do you get Jack to stay behind while your walking on. I imagine I would have trouble keeping Corado (or Magik) behind while I'm walking forward, especially since there is no food available.
I have my tripod set up on the side of the trail. And I throw down a few handfuls of feed, so it takes them a minute or so to eat it in the snow <G>, and then, IF I'm paying attention, I'll call them as soon as I see them lift their head, or they look like they are done? After a few recalls, they get wise that there's a BIGGER pile where I'm going so tend to follow more quickly! If there is no snow and you don't want to put the feed in the dirt, you can use feed pans or buckets.
I have been playing this with both horses out on the snowy woods trails for exercise this winter!!! What a hoot! I have some video footage that I'll try to put up later!
In dog training, it's called the "Come and Get It' Game, where you toss a treat AWAY from you and then run the other way, call the dog, toss the treat, run away, etc. REALLY fun game to get good, fast recalls, and also used it for puppy games in agility!
And thanks Brigit and Fiona!! Glad you enjoy the videos!! More to come for sure!