a faster rendering.
- your scene does not have soft shadows
- your scene does not need caustics (shiny colored light onto the table through a liquid, or sparkles off of glass onto adjacent surfaces)
- your scene does not have blurry metals, (stainless steel) only shiny metals
- your scene does not have SSS materials (sub surface scattering) like rubber, lamp shades, skin, curtains, blurry colored glass, etc.
Remember to save yourself much time, disappointment, and headaches:
- do not render on a prelim or low setting and then complain of the low quality of the lighting or some materials... it is called "prelim" and "low" for a reason.
- always do small test first with simple scenes and compare render settings.
- Start with lowest setting possible and work your way up to higher settings. Jumping to High+ may be overkill (too high) in many situations.
- do not set unrealistic deadlines for yourself when first learning a new program... while Twilight could possibly be one of the easiest rendering programs ever made, it obviously will still take time to learn to use it properly and in an 'optimized' manner.
- the easiest way to light a scene, and use materials with no effort for picking render settings is to use the progressive render settings. When using the Easy settings 1-7 without the + signs, in order to get benefits of 'faster' you may have to do some creative lighting techniques, use slightly different materials, etc. In some cases, in more complex scenes, the + settings may take just as long or longer than progressive settings... this is why it's important to do small tests
- the animation presets have a little something special that help avoid the light "sparkles" some may experience in some low settings and some lighting situation... when speed is needed, but the lower settings fail on your scene, try one of the Animation settings... Low+ or Medium+... they will render slightly longer than their companions in the basic set of render settings, but still faster than much higher settings.