Kitchen

[3DHighModel]

Corona Render Test.

Max - Corona and Photoshop (only for background)

[Juraj]

I would try getting some similar leveled environment directly in-render, otherwise it wreaks havoc in refracted panels, as you can see on your windows and balcony. I presume the original environment was much brighter when illuminating the room for this exposure, and this nulifies the reflection, so you got very clean but empty alpha channel. You can either manually paint these reflections back, or try to render some sort of environment directly, or use override.

[3DHighModel]

Surely there can be a better integration.
I have to try as you say to put the background directly in the scene to see what it does.

Thanks for the advice

[Juraj]

You can still composite the final environment in Photoshop, but it would look more natural directly. Did you used HDRi or Sky model ? Almost looks like hemispherical HDRi with lower black half because the balcony glass got that tint (unless that tint is inside material, that nevermind)

[3DHighModel]

I used an HDRI for the background.

[3DHighModel]

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