dome light&sky inside or sky in environment slot in max

[Vividus]

Hi Guys!

After all this years, I am getting confuse finding the right aproach for lighting especially for interiors

I am using 3.6

What it is the best solution for lighting? just to mention that in this case, I am not using vray sun in order to get a diffuse light coming in. Below the options

1-Dome light with a vray sky inside of the dome light and no vray lights on the windows

2-Vray sky in the environment slot in 3d studio max and vray lights on the windows with skykight portal activated and affect difuse,specular and reflection activated

in case either of those are correct, it would be much apreciated it if you help me out by telling me what is the right way

Thanks!

[padre.ayuso]

Whichever works best for you. However, with small window openings, HDRI will take longer to clean and may give you fireflies and LOTS of noise, in which case you use the sun system.

[Vividus]

I rendered the two options and what I found is that if i use option 1, render times are way higher and sample rate is very red on the other hand if I use option 2 render time are lower and my sample rate is a lot cleaner so it must be a difference unless I am doing something wrong

I would also comment that the the results in quality and lighting are almost the same

[LudvikKoutny]

Unfortunately, in V-Ray, when it comes to image based lighting, "whichever works for you" does not apply at all.

In 90% cases, you always have to use DomeLight to get reasonably performing image based lighting. Those remaining 10% of cases are situations, where you are in an exterior area, and are illuminating your scene with either just constant color, or with non-HDR spherical image that does not have any significant variance and/or contrast. But even in those cases, DomeLight won't perform much worse. So simply use DomeLight all the time, and you can't really go wrong.

[Vividus]

But when I use dome light , should I use skylight portals?

[LudvikKoutny]

But when I use dome light , should I use skylight portals?

Nope, definitely not. They don't work together.

[jironomo]

When using a hdri only (dome light) to light an interior (ie no portal lights or vray plane lights in windows) do people use a hi res HDRI (ie 8000px)? Would using a much lower resolution hdri (1200px) or even just a jpeg in the dome light reduce render times/noise?