Hi Paul,
Thanks for sharing your experience. Seems like it is worth to modify the GoPro. Btw, where did you purchase the 60 degree lens?
The rolling shutter is more of an issue in my case because a) I fly at a low altitude of only 10 to 25m (at low speeds) and b) I do not have a gimbal. Might be worth to invest in one
I reprocessed some old images today, and thanks to Porly's post earlier this week I thought I would give masking another try. I already used it to remove people (the pilot, myself) and waves / reflections in the water) from the images. But today I generated a mask in Photoshop and applied it to all images in order to get rid off all the blurry areas around the edge of the images (see attached png-file, works for GoPro Hero 3 black images with 12 MP, WIDE setting). So you can still use shoot in WIDE with 12MPG (instead of approx 7MP when in normal as mentioned by Porly).
I must say, the result is much better. Ground control points are accurate. Dense point cloud and mesh look both great, without a lot of "cleaning" necessary.
Happy with the results from the GoPro Hero 3 black. The Nex 7 on a hexacopter will of course give you better pictures, but at a much higher price. Plus you have a quite bulky setup. I actually prefer to have a small system like a Phantom for photogrammetry because of several reasons.
a) CASA seems to change the laws for UAVs here in Australia and will allow to fly small ones (under 2kg) without a special operators certificate
They say that it has not enough kinetic energy to really harm a person. I agree.
b) It is less expensive to buy it and to repair it in case it crashes
c) Easier to carry around (important for the work I do, because I work in remote areas where I have to carry the equipment for several km)
d) You can take it on a plane as carry on luggage
e) Charging batteries in the field is much easier (you only need a car and DJI's special car battery charger). Try to charge a 6S LiPO with 10000mAh in the field. Possible, but expensive.... and heavy.
Really like the exchange of experience here in the forum. Great stuff guys, keep up the good work.
Cheers
SAV