Hi, I have a camera which has some fisheye effect (not like GoPro) and I wanted to correct this. Do you have an idea how it can be done? For the time being, I had only one idea: to create (in Blender) a grid mesh (see attached picture) and shade it with unlit image from camera. But I think Vuo showed me a bug - when you shade a grid mesh with unlit image shader it produces this weird effect (see another attached image). I've corrected direction of normals of mesh, nothing changes.

When you try to shade with image a flat mesh with more than 4 vertices - it produces this dissortion. Should I create a bug report?

Cheers, Teo

Comments

Ok, I've solved this - maybe

dumski's picture
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Ok, I've solved this - maybe it can be helpful for someone. Your mesh has to have correct UV mapping (texture map). You can check what is your current mapping by shading a mesh with "Shade with Vertex Attribute" node - Vuo will show you how is your mesh mapped.

EDIT: I've added a captured windows of Vuo app which shows pictures - left one with correction, right directly from camera.

Nice! Yeah, it's important

smokris's picture
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Nice! Yeah, it's important to get the UV map correct. If the mesh lacks a UV map, Vuo makes an attempt (spherical coordinates) which is often better than nothing, but rarely as good as a human-made UV map.

Alternatively, you could try using the Bulge Image filter to correct fisheye barrel/pincushion distortion. For the image you provided, Scale=-0.5 and Radius=1.5 gets pretty close to rectilinear.