Why is my lighting too bright?

Question

I'm not sure why, but in the scene that I'm rendering (My first time, so I'm doing a donut) the lighting just doesn't work. As shown in the image, everything in the light is overly bright, and then it suddenly cuts off to dark. Is this a processing issue, or did I just do something wrong?

Answer 1

Lower down the Strength of your light

Answer 2

What you have presumably done is changing a default Point lamp to a Sun lamp. The Point lamp usually has a Strength of 1000W. Switching to a Sun will keep a value of 1000, but the unit is W/m², which is a lot brighter than the Point lamp. So the answer from @moonboots is most likely the solution in your case.

The result is not surprising and just what you experienced, a much too bright light (although our sun actually is about that strong, but eyes, cameras etc. usually compensate this by our pupils or camera's exposure settings):

The Radius of a Point lamp (or Angle of a Sun lamp) is a setting of their size and therefore determines the sharpness of shadows on both lamps.

A difference between both lamps is that while a larger radius decreases the intensity of a Point lamp, because the power stays the same while it is spread over a larger volume, this doesn't happen with a Sun lamp, since the unit W/m² is power per area, so the intensity stays consistent.

And although the Strength was causing your problem, for the sake of completeness (and because it was the solution to another similar question here) I will mention another possible reason, because this is something where Point and Sun lamp behave differently as well:

Since the Point lamp more or less resembles a punctual light source like a light bulb in a room, the effect of it's power and size is not independent from the size and distance of other objects.

In the following example I've set the Strength of the Sun to something lower like 3 to not fully overexpose the objects. On the left is the same scene as before (apart from the darker sun). On the right you can see what happens if you scale it all down to 10% of the original size.

The Point lamp still has a strength of 1000 W, but now it seems much brighter because it is also much closer to the objects. And since I didn't change the Radius which makes the lamp now 10 times bigger than before, the shadows are much softer.

The Sun lamp however also keeps its Strength value, but it is in W/m², so since I shrunk the objects and the area which gets light is also smaller - but the relative amount of sunlight stays the same. Also the Angle remains the same and therefore the sharpness of shadows doesn't change.

To oversimplify it, think of the settings on a Point lamp as absolute values, whereas the Sun lamp's values are relative values. For the Point lamp 1 $\neq$ 10 is valid, but for the Sun you could say, 10% of $x$ will always be 10%, no matter what $x$ is.