I did some more tests.

The problem happens shortly before the render finishes.

It is hardly noticeable with portraits, but it can be easily spotted in background figures.

There is a slight diagonal shift between an (antialiased) OpenGL preview and the final render, but that is normal. (PP-2014 and P11 do it, too)

BUT...

if you compare screenshots taken of the preview render and the finished render, the distortion becomes obvious:

Notice the enlarged forehead and the squished face on the final render at the right!

(I disabled all shadows for a better comparison.)

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Now when you EXPORT the render and look at it in IrfanView, the distortion goes away!

This is probably a non-issue for most, but I find this behaviour highly annoying, as I spend most of my time looking and comparing renders INSIDE Poser.

I can't do proper figure work, if the test - renders I'm looking at are distorted.

PP-2014 and P11 don't do that.

I haven't installed P12, as I only bought that to get the better upgrade price.

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Anyway, if it can be fixed in a reasonable timespan, fine.

If not, I have to return P12 and P13 and go back to P11, speed increase or not.

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There are more problems with OpenGL in P13, btw.

I already mentioned the Material room.

But there is also some ugly self-shadowing (black polygons) with older / low rez figures. Subdivision can reduce it, but the point of using older /low res figures is to have a more responsive OpenGL.

And preview subdivision of course negates that.