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Following the topic in problems thread I desided it would be a good idea to make a separate thread here so others can look for it is they have issues.
I would like to explain what is affect shadows and why it is there, and how else light can pass through the glass, and what are the physical properties of that:
Affect shadows is a "fake" or a "cheat" to allow fast renderings of light which has passed through glass. However its physicly incorrect. The reason for this is, every light energy that has passed through glass has become a caustic energy.
Therefore you need caustics for the light to show from outside in interriors. For this the refractive caustics must be turned on, however because of often used biased method such as irradience map, caustics will never show, thus the illumination from passed light through glass will not appear, producing result shown in example 3 below.
So, to see the light we eather turn on affect shadows, which is imo a good cheat for a fast and effective rendering time, or we turn off affect shadows, turn on refractive caustics and set illumination method to qmc/lc with very high sampling, or lc/lc in ppt mode and wait for many hours for the light to show.
Here are some research tests I've done for maxwell forum, but they also apply to this:
Image 1, shows maxwell caustics illumination through glass
Image 2 shows vray glass with affect shadows
image 3 shows when affect shadows is turned off
And image 4 shows physical caustics in vray with affect shadows off, and refractive caustics on
I would like to explain what is affect shadows and why it is there, and how else light can pass through the glass, and what are the physical properties of that:
Affect shadows is a "fake" or a "cheat" to allow fast renderings of light which has passed through glass. However its physicly incorrect. The reason for this is, every light energy that has passed through glass has become a caustic energy.
Therefore you need caustics for the light to show from outside in interriors. For this the refractive caustics must be turned on, however because of often used biased method such as irradience map, caustics will never show, thus the illumination from passed light through glass will not appear, producing result shown in example 3 below.
So, to see the light we eather turn on affect shadows, which is imo a good cheat for a fast and effective rendering time, or we turn off affect shadows, turn on refractive caustics and set illumination method to qmc/lc with very high sampling, or lc/lc in ppt mode and wait for many hours for the light to show.
Here are some research tests I've done for maxwell forum, but they also apply to this:
Image 1, shows maxwell caustics illumination through glass
Image 2 shows vray glass with affect shadows
image 3 shows when affect shadows is turned off
And image 4 shows physical caustics in vray with affect shadows off, and refractive caustics on
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