nah, it's not due to the alpha channel. it's because the pixels get burnt because the outside is very bright. enabling the "clamp output" in the color mapping settings seems to fix that.
thanks ! I use low settings because it's a wip and I don't want to wait 2-3h for it render, this one took ~6 min to render at that resolution. for "final" renders I use much higher subdivisions for the reflections and the DoF.
the borders of the walls gets some aliasing
Itīs a pity the Settings are that bad, better check out the AA and Reflection + DOF Subdivs...
I use low settings because it's a wip and I don't want to wait 2-3h for it render, this one took ~6 min to render at that resolution.
for "final" renders I use much higher subdivisions for the reflections and the DoF.
I didnt know it was a WIP, looking forward for your final render now !