"Drat, that just looks incorrect. But the model is right! Whats wrong?"
Have you ever found you self saying this? I have it happen all the time. Its really hurts when you look at it and it just doesn't feel right. Well here are a list of things that I do that sometimes help make your model better.
- Bevel all sharp edges in your model.
- Make sure your model or scene is well lit and turn on ambient occlusion(In the world panel).
- Don't make colors pure white or pure black(I know I mention this a lot but its very true and adds a small touch of realism).
- If something is reflective don't make it completely reflective(add a slight blur or fuzziness to it - turn down the gloss)
- If you need to light all sides of an object, use indirect light and/or environment lighting.
- If the model doesn't look right just check it against a reference image.
- For interior renders use an external render engine or watch a tutorial(Greg Zaal has a very good one at blender nerd)
- Make blurry shadows and turn up samples(Soft Size in Lamp settings)
- For human skin turn on SSS(Sub Surf Scattering)
- Add textures for everything(If its one plain color add a texture for the Specular intensity)