bake lightmap with hard edge

U3d: 5.4.1f
how can i fix this problem

left: custom fbx , right : buildin Sphere

it is really simple setting

Those are seams that result from UVs not being continuous.

There’s a number of things to minimize the effect:

Reauthor the UV2 uvs so that they have as few seams as possible.

Use higher baked res.

Also try turning off “compressed”.

i tried unity4.6, everything is perfect.
i think the beast is better for baking

no change

It may be, but that doesn’t mean you can’t fix this and get great results in 5 (at least on a scene as simple as this).