Topic: inside/outside light

[3dfh]

i have a problem with the light...
i want to make a render of a house from the outside by night, with some light coming form the windows. But if i put a light in the middle of the room inside and go outside to take a picture, i don't see the light throught the glass...
 Does anyone knows why and how to fix it?

[Ecuadorian]

Just replace the glass with a self-emitting material.

[peterm]

Any light should cast an area of light through the glass on to the outside area by default if the window is a transparent material, so it could be the material or maybe the light properties.

Check that the window surface is assigned a Lumion Glass material, or there is no other non-transparent surface at the window (eg curtains) blocking the light.

If the lights range property is small then it may not caste an area of light past the window.  However you should still see the lit area of the light within the room, and as you can't from your picture it would seem that the material type is the issue.

Using a light will give that correct look of lighting the outside area but in some scenes might not be worth doing due to impact on render times or time to place lights in the scene, so a quick fix solution is to just increase the emissiveness (as Ecuadorian mentions) to make the glass look lit.  However it only brightens the area of glass and does not of course create a correct lit area as cast from a light.

[3dfh]

ok, i have try many different materieals, but i still can see the light.
finally, i have just increase the emissiveness as you said,. it works, but i have to change the properties of each windows any time i want to switch between day and night...
i think i have done something wrong, but don't know what!
thansk for answering  petern and Ecuadorian 

[Morten]

ok, i have try many different materieals, but i still can see the light.

Any light from the sun or from spotlights/omnilights will pass through the default Glass material in Lumion.

If it doesn't, please place the camera near the problematic area and export the full scene as an .ls2 file. Then zip it, upload it to WeTransfer.com and forward a download link to my email address (morten [at] act-3d.com).

[peterm]

hmmm, sounds like there might be some other surface at or inside the window object that needs removing.

Can you show a pic of your scene, maybe close up to the window, in daylight, with the window applied a glass material? might give a clue.

[3dfh]

you are right petern, there were an other surface in the window... so that's good now, but i've got another problem. i put a light in the lamppost on the street, but i don't want to see those shadows... any idea? i have try with an omni light, it was ok, but the light is not powerful enough...

[Morten]

If omni lights are not powerful enough (I assume you tried to set them to the maximum intensity/radius via Edit properties), I guess you could try to place the spotlight above the lamppost, so that the shadow from the lamppost itself will be small(er).

[3dfh]

yes, i have set them to the maximum, but still not enough powerful!

Above... So simple! why i haven't think about it earlier! 

[peterm]

Was wondering about those shadows.

It looks to me like they are the result of parts of the lamp mesh rather than the lampost. 

If the light is placed anywhere in-between (ie where a normal bulb would physically be), say between the outer lamp top cover and any mesh surface for the bottom cover, then a shadow will be cast of the lower mesh and is very large due to closeness to the light. This is perhaps not the shadow one would normally expect to see just of the post when the lamp has a semi-transparent lower cover.

I would try moving the light down just below any lower/bottom mesh surfaces.  The light will still cast a shadow for the post, but the lamp mesh itself will not interfere and make a shadow not required.

Same for any internal lights unless the mesh surfaces are needed for shadows, and what parts it is quicker to make transparent compared to just moving the light down slightly.