My first “Personal aerial photo-mapping session with balloons or kites,” a fundraising auction item, was successful. On Sunday, 7/22/12, Nile Runge, who had successfully bid on the item at a Livermore Rotary Club fundraiser, and I flew two mylar sleeping bag balloons with a Canon A1200, shooting in continuous mode in a juice -bottle rig. We flew at Shadow Cliffs Regional Recreation Area, off Stanley Boulevard, Pleasanton, CA, a part of the East Bay Regional Park District.
Donating such sessions to benefit auctions may be of interest to others as a way to educate and share the aerial photo-mapping techniques with others by donating a few hours of their time and inexpensive gear like a couple mylar sleeping bag balloons, a homemade kite and a juice or soda bottle rig, and the resulting photos and map to get others started.
There were a number of important lessons learned, discussed below. However, the photo mapping session was successful. The camera ran for over an hour and 45 minutes and was still shooting when we brought it down. The camera shot over 4200 photos. The resulting draft stitched map is available at: http://mapknitter.org/map/view/shadow-cliffs-pleasanton-ca. Photos are at: http://www.flickr.com/photos/coylepdc/sets/72157630756189698/ Video is at:http://www.youtube.com/watch?v=ZRPOO5fiaro&feature=youtube_gdata_player
Issues and lessons learned:
While I had done a safety moment before we started and noted the trees and the hazards of snagging on the trees, as soon as we launched the two mylar bags with the camera and enclosure rig, the wind pushed the balloons down, close to the treetops and immediately snagged our line on the tree nearest us and the next tree downwind.
After repeated unsuccessful tries to put out enough line to get the balloons to climb to unsnag the line from the trees, I decided to climb the first tree and cut the line loose from the reel. I tied and wrapped the downwind end of the cut ine on a rolled up glove. With Nile downwind to catch the cut line I released it. I had to repeat the process for the next tree downwind.
Nile was a good sport about the unanticipated difficulties and he came up with several ingenious suggestions. For example, he suggested we throw our heavier kite line over the balloon line between the two trees and use that loop to pull the balloon line down to confined it so he could securely grab the rolled up glove tied to the end of the cut balloon line when I released it from the tree. He did this successfully and then we proceeded to unsnag the rest of the line. We were able to wind our line onto the glove as we worked our way downwind and freed snags at two more trees by playing the line out till enough altitude enabled the line to pop loose from the top of the trees.
I was careful and cautious while climbing the trees. I really did not want to take a fall. Even so, as a result of this unplanned activity, I've got “road rash” type scrapes on my forearms from the oak tree bark and scrapes on my shins from the small branches I had to push through to reach the snagged line.
Clearly, this is a hazard I will do my best to avoid in the future. More care in selection of launch location and more respect for the effect of winds above ground level. At ground level, the wind was too light to launch a kite. However, even slightly aloft, it was enough to really push the balloons horizontally, down and low, snagging the line in the trees.
At the end of our flight, after we had gotten clear of the trees , walked through the parking lot and were bringing the kite down, a park police officer drove up to us, got out and asked if I had a permit.
I replied that I was within FAA regulations to fly. However, he informed me that there was a park policy that required a permit to fly and if one was granted it did not allow exceeding 400 feet above the ground or flying from the parking lot. He said when they needed to fly their park helicopter, they did not want kites or balloons above 400 feet. I explained that I had checked the website and found no information about permits being required or prohibitions against flying kites or balloons. I asked him how to find the right people in the park organization to contact. He said it wasn’t so easy, but gave me a card which had information for the East Bay Regional Park District so I can follow up with them and find out the permit process. I also realized that we were within a five-mile radius of the Livermore airport which calls for other notifications as described in: http://publiclaboratory.org/wiki/mapping-curriculum-regulatory We deflated the mylar bags just enough to get them inside Nile’s Prius so they were still pretty full of helium. We gathered up the rest of the gear and drove back to Nile’s house and transferred it to his garage. We transfered the photographs from the memory card to his system which took quite a while. We launched Knitter, but it warned it doesn't work well with Internet Explorer. We were short of time, so didn’t get him going with alternate browsers like Firefox or Chrome to explore Knitter.
Later, I transferred the photos on my system, got a draft map stitched in Knitter and started the export process. I emailed Jeff and Stewart that I had trouble with the export not completing. Stewart replied that at least some formats exported okay, but put in a report at Gethub regarding not getting a jpeg. The resulting draft stitched map is available at: http://mapknitter.org/map/view/shadow-cliffs-pleasanton-ca