Making transparent the ceiling of a room, but opaque for sunlight ?

[Walter125]

Hi,

When we take a photo of the 3D view, or when we disable the ceiling of a room for the virtual visitor, then, on the photo, we can see the sunlight going into the house.

I think the following option would be useful:

Making the ceiling of a room totally transparent from inside the house to the camera, but totally opaque for the sunlight, and other outdoor lights, that are placed outside the house.

[Keet]

Why would you disable the ceiling for a photo?

Anyway, you can simulate what you want by using a box on top of the ceiling (the floor on the level above it): stretch a thin box so it covers the ceiling and make every side invisible except the top. When you look at the box it's only visible from the top and thus should block lights from above. Being only visible from the top also means you look "through" it from the room below where your camera is.

[Walter125]

Thanks for the tip, I will try. Are you sure it works also for photo quality 3 and 4 ?

I tried with a special object, instead of the box, a plane with only two faces: the top and the bottom and a thickness of 0,1cm, making the bottom transparent but not the top. It doesn't seem to work.

I would like to disable the ceiling but keep it opaque to sunlight, in order to get an outside aerial photo of the inside of the house. With the same lighting as if the ceiling was here to stop the sunlight.

[Keet]

That's different from what I understood from your first post. From that post I understood you had a camera inside the room and wanted to look through the ceiling to the outside but without the sunlight.

Now I understand you want to look from outside into the room (from above) but without the sunlight (like the ceiling blocks the sunlight)?
Try to set the clock at midnight, there's no sunlight at that time. Then you can just disable the ceiling and look into it from above and only see the lights you added yourself.
If you want to have the refection of your lights onto the ceiling use the same box as I mentioned before but now with only the bottom visible in the color of your ceiling. That way it reflects your lights as if there is a normal ceiling but you can look into it from bove.

[Daniels118]

Of course you can set the time to midnight to completely remove the sun as suggested by Keet, but maybe you still want the sun light coming from the windows. If this is the case, you can use the workaround described by me in this post:
https://www.sweethome3d.com/support/forum/viewthread_thread,11807#55022

[Walter125]

@Daniels118

Thanks for the tip.