Maybe you can describe what you are doing a bit. The new Render tab is somewhat intuitive, but it does require some finesse.
Here is a typical approach that I might use to genreate a renderingm after I have all of the geometry and materials in place, etc.: (And in this walk-thru, I am referring specifically to an exterior redering.)
1. Make sure that I am in a perspective view. You can use a camera, as you mentioned, or when in a 3D orbit, right click and choose perspective. (Or there are probably 4 other ways to do this as well.) BEING IN PERSPECTIVE AFFECTS YOUR ABILITY TO USE THE SUN AND SKY.
2. Go to the Render tab.
3. Under the render tool, under the render tab, you can pull-down pre-set settings, from Draft to Presentation. These are pretty reliable to get started.
4. Under the little Render arrow, you can further refine. But that is for another time.
5. Two important things to do: Turn on the sun (click the big sun icon an inch to your right) and turn Sky and BackGround illumination on. This will give the the ambient lighting and soft shadows of the sky vault.
This should get you started.
If you are still getting blotchy, click on the tiny arrow that says Render: Increase your image output size, as well as the render quality )1-5 scale.
When you really want to do a final draft, there is one setting that I feel is critical. You can click on the microscopic arrow, next to the word Render that is pointing down and to the right, OR you can type in RPREF, for advanved render settings. Look for FINAL GATHER, and turn it on. This will use a good bit more memory, and take longer, but will make for a nicer final output.
Oh, and click the Teapot Render button!
Hope this helps. Hit me with any specific questions.
