Distortion around the stitch

[Salmaasa]

Kindly notice the attachments. There is no distortion around the stitches in the model but when I render, there is distortion. Why is this happening? And how can I change this? Thank you.

[romullus]

Do you use displacement on the model or its material? Does the model have turbosmooth modifier which may have different settings for viewport and for render? More info please.

[pokoy]

If the rest of the map is flat this could be just wrong gamma - make sure your displacement/bump is loaded with 1.0 gamma, not automatic (or 2.2).

[Salmaasa]

Do you use displacement on the model or its material? Does the model have turbosmooth modifier which may have different settings for viewport and for render? More info please.

The model was an editable poly with no modifier. Looks like the material was the problem. It was fixed when I turned off the bump map. Thank you for your suggestion.

[Salmaasa]

If the rest of the map is flat this could be just wrong gamma - make sure your displacement/bump is loaded with 1.0 gamma, not automatic (or 2.2).

Looks like the material was the problem. It was fixed when I turned off the bump map. Thank you for your suggestion.

[romullus]

Looks like the material was the problem. It was fixed when I turned off the bump map. Thank you for your suggestion.

I don't think that's material's, or more specifically its bump channel's issue. I think the problem is with your object's UV mapping. Most likely the distortion is still there, it's just less visible now when you turned bump map off. You could apply UVW unwrap modifier on the problematic mesh and relax its UVs until distortion is mostly gone, unless your chair is using bespoke baked textures, then you should be extra careful not to mess UVs too much.