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I try to practice on rendering process, but lighting is not working.

I set up one light (Area Type), first picture I set light's strength to 10000 and its still dark.

Second picture I set light's strength to 1 and its still dark.

How can I solve this problem? So sorry if image too small

enter image description here

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  • Is your lamp object renderable? – Duarte Farrajota Ramos Oct 19 '17 at 18:30
  • Hemi lamp is dark too.

    Thanks for correcting the mistake. My english is so bad.

     – 0 0 0 Oct 19 '17 at 18:33
  • Try making an object your light. All you do is simply create an object with an emissive material. – HappyBlenderUser Oct 19 '17 at 18:39
  • Are you using any clamp on the sampling section? Is the light in the same layer? –  Oct 19 '17 at 18:40
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    @YusaMac205 Hemi Lamps are not supported on cycles they are interpreted as sun lamps –  Oct 19 '17 at 18:41
  • Maybe related: https://blender.stackexchange.com/questions/45195/cycles-emission-shader-does-not-bring-enough-light/45381#45381 –  Oct 19 '17 at 18:42
  • Check the size of your models, try selecting all of them and scale them down and do the render again. – AdverickMegrezWD Oct 19 '17 at 22:13
  • Please use the [edit] link at the bottom of your question (https://i.stack.imgur.com/lXFuK.png) and add more information. We don't know how you set up your project. Add images that might help us understand your scene. Consider sharing your .blend file so that others can inspect it. You can upload it at http://blend-exchange.giantcowfilms.com/ and then paste the resulting link as part of your question. –  Oct 20 '17 at 02:51

2 Answers2

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Note sure if you have already found the answer and resolved the issue... I think it's something to do with the Blender unit settings. I have seen this issue if the Blender unit is set to MM (unit scale: 0.001) in the scene tab. In that case the emission value is equivalent to milliwatt (0.001W) - and you need to multiply the emission value with 1000 to get 1 watt. So, 100W would be 100000 in blender unit. Also, the size of the Area light also matters - larger size of area light with the same unit gets softer and less brighter.

Unfortunately I haven't able to find any information about the co-relation between scene scale and Blender emission unit anywhere so far - so this is my hypotheses - if anyone has any better and more accurate explanation I would be very happy to know.

saicode
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  • Upvoted because this answered a similar issue I had. Occurred when setting units to metric, scale .01, and cm. Setting light power 100 times normal solved light problem. However, in same blend file, setting units to none did not allow me to use normal power, because now all existing objects became 100 times too big, and the effect of this was addressed by cegaton above. – PSBDave Jan 19 '19 at 21:27
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There are a few possibilities why this could be happening, unfortunately the question does not have enough information to be able to determine the cause for sure. So here are a few things to look for:

  • The light is blocked by other objects or is not reaching the featured object

    Check that there are no hidden or disabled objects blocking the path of the lights.

  • The lamps could be disabled for rendering in the outliner

    To fix enable the camera icon.

    enter image description here

  • The lights might be in a different layer that is not being rendered.

    enter image description here

    To fix move them to the active layer or enable the layer for the lights as part of the rendered layers.

  • The overall birghness of the scene could be clamped in the render settings.

    enter image description here

    Any value below 1 in Clamp Direct, will make the image darker. Clamping is really preventing the ligthts to be any brighter than the value specified.

    To fix, disable clamping by resetting the values back to 0 (0 = no clamping)

  • The model might be too large or the lights might be too far away so the model is lit just by the color of the environment.

    Cycles uses values close to those of the real world. If your model is set at a scale where the turntable is as large as a city block, then one small light will definitely not be enough, or it would need to be very bright. As a rule it is better to try to keep scenes to real world sizes.