Panorama Issue

I used Affinity Photo to do this panorama - total 22 photos. Any idea why the top of the roof is curved? I also tried ON1 Raw and got the same result.

Thanks-

I'm thinking it is because as you shoot each picture you have to pan the camera to the next position and, as you're panning from a fixed point, each progressive picture is part of a circle. The distance from the sensor plane to the left extreme of the building is greater than the distance from the sensor plane to the center of the building. So when the algorithm assembled this it had to curve the building to get the correct alignment.

Just my guess.

It's an easy fix in PS especially since the curve is slight.

What you are seeing is the normally expected perspective distortion as would be expected when using any extream wideangle lens. The perpective distortion is due to angle of view, not focal length. You could shoot lots more images using a 600mm lens to get the same coverage and the final image would still have the same degree of distortion, although it would have a lot more detail.

As saea501 says it is relativly simple to correct in post processing. One tip to remember if you do want to correct this is to make the pano quite a bit bigger than you want, so you have plenty of spare pixels to bend about during the correction. This will give you more options when it comes to making the final crop.

Alan

Thank you both. Makes perfect sense. I don't have PS but did watch a couple of videos on how to fix. I did not find anything similar in ON1 Raw - but appreciate the tips.

This distortion is easily corrected with simple pixel editing tools like the Warp tool and Distort tool in PS. Also, if your pano application gives you various projection options, choose "rectilinear" instead of "equirectangular" or "spherical" or "cylindrical."

kirk

There is an Affinity Photo tutorial on how to correct panorama distortion:

https://vimeo.com/1706​33074

Kirkt and WiscTim - thank you both!

Just one other note. You can usually fix this kind of distortion in the pano-stitching software before you stitch. In Hugin, for example, in the preview window's move/drag tab, you can adjust the yaw, pitch, and roll for the pano by simply dragging around.

Good info - thank you!