Currently Corona can bake to square aspect ratio textures only. Would be very nice to get support for non square aspect ratio too.
This is a 3ds Max limitation, sorry
Both mental ray and scanline allows to do that.
Edit: just checked MR RTT render times are identical for both resolutions 1024x1024 and 1024x512, so most likely that means that 3ds max just simply downscales when saving. Very advanced, Autodesk…
nice… also I get only square renders from scanline. And when I setup 1024512 resolution, 3dsmax provides me with 10241024 bitmap
Probably you’ve got a version where cheats are disabled :]
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