How to stitch Xiaomi Mijia MI SPHERE 360 photo in PTGui?

[Hok Min Lie]

Hi fellow group members,

I am thinking of buying Xiaomi Mijia MI SPHERE 360. Use it to take 3 exposure bracketing photos, convert those pictures to HDR.  Then use PTGui to stitch the photo (convert two spherical pictures to an equirectangular).

Here is a link to a HDR photo: https://drive.google.com/open?id=0B932X4gzodDUX09CYVBsYUhyTUk

My question is: is it possible to stitch the photo in PTGui?

Thanks,
Hok-min

[John Houghton]

Yes, it's possible to stitch the images. See my stitch at https://www.sendspace.com/file/64636m .  It's not perfect, but to enable the lens distortion to be corrected properly, you would need to perform a special calibration test to evaluate the lens parameters more accurately.  You do this by shooting the panorama twice, panning the camera around through 90 degrees between them.  This gives a total of 4 circular images which have adequate overlap to be stitched correctly.  Once this has been done, the lens parameters evaluated in the calibration test can be used in subsequent stitches of just the normal single pair of images. You would use a template containing the preset lens parameters for convenience.

John