I have watched a bunch of videos and read many tutorials on lighting, but when I try them myself it looks really bad.
The issue is that the render is very dark. First I tried with just the light from the sky, but that didn’t do much. Adjusted the time of day to get light coming in through the window. Still dark…
Then I added a rectangular light just outside the window, but then I get some dark parts, and some which are overexposed. I have tried playing around with the settings for the rectangular light, increase the intensity, increase exposure for the camera settings. I get the best results when I reduce the postprocessing Highlight burn to 0 and decrease the exposure.
I am using V-Ray 3.60 trial version
Notice the overexposed area in the corridor and on the shelf, while the image is overall quite dark
Your image doesn’t look all that dark to me. There are some burned out areas such as the hall as you mentioned but also at the bottom of the shelf where the light is hitting it. You need to reduce the contrast between the light areas and the dark ones. Add some more lights in the room to light what the window light isn’t.
If that image looks too dark over all, you should probably also check your monitor.
I don’t think it’s my monitor, I have seen many other renders that look just fine on my monitor.
Also, it seems the light is very strong, as it’s coming directly from the rectangle. I have an overexposure in the window, even at the lowest level in the highlight burn.
I think the problem you are facing is that the rest of the scene is lit only by indirect light scattered off things hit directly the very bright light through the window. Because the indirect scattered light is weak compared to the direct light, you get extreme contrast. Increasing the brightness of the direct light isn’t the right way to deal with this situation.
As @DaveR noted, you need to emulate the way that professional photographers work. They avoid intense spotlights wherever possible, preferring diffuse lights. But mainly they use additional lights and diffuse reflectors to put some mild illumination into the dark areas and to soften shadows.
Ever wonder why when you take photos at the beach everyone has harsh shadows beneath their eyebrows and chin, but the models in the nice beach photos in ads don’t? It’s because the pros have white reflector sheets just outside the camera’s view to direct some light into those shadows.
In most renderers you also have ability to add some general ambient light to a scene. That isn’t really a physically feasible lighting, but it can be effective when a scene seems overall dark.
So how do you suggest that I achieve this effect in my renders? I added another rectangle light in the ceiling of my render, but maybe this will not produce the most realistic effects. Do I add a light sphere in the middle of the room?
It’s just that whenever I watch a Youtube tutorial they only need to add one light source and everything looks perfectly fine for them
