Adjusting Equirectangular "Seams" to Reduce Distortion for 3D Rendering

[Mark C]

Hi everyone,

I’m a beginner to spherical projections and I’m currently experimenting with creating HDRIs using a drone (shot at approximately 30m altitude).

I’m using the Equirectangular projection, and while the images stitch together fine, I’m looking for a way to "decide" where the seams of the projection fall. The reason why is because I'm currently using it for 3D rendering and at the moment the projection looks too distorted at key landmarks. By adjusting the "seams", I'm hoping to move the landmarks to the areas where the projection is least distorted.

Am I understanding this correctly that I can "slide" the projection to preserve detail in specific areas? Or is the distortion fixed regardless of where the subject sits on the horizon?  

If there are any external resources or documentation I should read to understand the relationship between drone stitching and equirectangular distortion better, please let me know.

Thank you!

[PTGui Support]

Hi Mark,

I'm sorry, I don't understand the question. Your attached image shows
cube faces in an equirectangular projection. Are you exporting cube
faces from PTGui into your 3d application, or are you exporting a single
equirectangular file? The output from PTGui (equirectangular or cubic)
is not distorted, it's just a particular projection of the 3d world.

Kind regards,

Joost Nieuwenhuijse
www.ptgui.com

> Screenshot 2026-03-11 012354.png
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