G Davidson
 Second Officer
Flight distance : 263465 ft
United Kingdom
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Matthew Dobrski Posted at 2018-1-6 16:10
Pardon my curiosity, since this issue is grabbing my attention recently. So, you're taking a series of stills rotating your drone manually in - I assume - relatively calm weather, aiming the camera level with a horizon roughly at half the frame. Than you take another series of stills with DSLR on tripod, aiming above horizon to capture sky features. To my understanding both sequences must be taken with identical frame resolution, determined WB and rock solid apertures (i.e. full opening, in a way similar to timelapse technique?). Finally you stitch both sequences in software. I'm sure there's much more involved in the process to get such stunningly consistent image.
Would it be possible, however, to shot second drone sequence with camera aiming below horizon and get much deeper stitched panoramic view? With automatic Pano feature being implemented in Go app recently this should be no brainer, I assume, but is this assembly software able to deal with such?
The panorama shot from the drone is usually around 3 rows of 6 (horizontal row, then approx -30 and -60 degreees) which gives a full caprure from horizon to directly underneath the drone. Nothing is missed out in terms of the view from the drone - everything there is to see from that viewpoint horizontally to directly below below is captured. Exposure wise, I try to ensure that I have exposed correctly for all parts of the image. Not as simple as it sounds where low sun is involved - I may have to blow out the sky to get the landscape correctly exposed but as long as there is enough overlap between images containing blown sky and properly exposed sky, the stitcher (Kolor Autopano Giga) will patch in the parts from the correctly exposed sky. As I have an orginal P4 without aperture control, the aerture is indeed fixed but had I had a P4 pro, I would have locked the aperture.
I generally lock WB to “sunny” on both the Phantom and the DSLR and shoot the DSLR sky image with manual exposure (usually around 1/250s f7 @ ISO 64)
Everything is shot in RAW which gives more latitude to tweak exposure before feeding the imagery into the stitcher. The stitcher is tolerant of differing exposures per image (within limits) and will generally try to optimise exposure across the whole panorama.
I only shoot 6 photos from the DSLR using a 10.5mm fisheye. That does mean that there will be a difference in focal length between the panoramas but it does not matter  The resolution of the upper and lower half of the images are not the same but get resized to fit the pano horizontally.
I do prefer fairly calm conditions to limit what moves between shots but there are ways to mitigate any movement e.g. all those wind turbines were spinning - it was necessary to make sure that overlapped parts of the wind turbines contained complete turbines so that the stitcher could run the stitching seams between the turbines without cropping off blades that move between shots or indeed seeing 6 blade turbines
You’ll see that my shooting style does not lend itself well to an automated process as I’m deciding exposure and composition per shot based on what I know will make life easier in the stitcher. However, when it comes to coastal shots with lots of sea - all bets are off
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The resolution of the upper and lower half of the images are not the same but get resized to fit the pano horizontally. 
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