I thought twice about putting up this image as it's not very exciting.
However I had to break up a faulty television to rescue this image!
It transpired I’ve been fortunate so far in that my choice of image overlap was sufficient to avoid the areas of vignetting inherent with the Phantom 4 camera. Today, I was not enjoying the weather and decided to shoot fewer images with less overlap to save time. My stitcher was not happy with that and the results were rather poor – see the thumbnails at the bottom of the post comparing bad vignetting and a good result.
Why did I break up a TV…? I needed to make a “Lens Cast Calibration” profile to map out the vignetting and colour cast near the edges of the image. For that, I needed a uniform source of light to place in front of the Phantom and LCD televisions have white light diffuser sheets in them. Once I got a diffuser sheet out of a 36” TV, I went outside in this overcast day, held it in front of the Phantom pointing skwards, shot a reference image, showed it to my RAW editing software and made a correction profile.
The profile was then applied to my troublesome images and all was well when stitched!
Shame the image was so boring though but it was worthwhile in that I now have a profile to correct vingetting/colour cast specific to my P4
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