just fast and easy question: should I shoot B&W pictures out of camera or do them on post processing? Should I change some settings on camera, if I know that I will use them as B&W? Checking shadows and burnt areas is key thing, I think? Just like with the colors.
I am using D90 but this may concern of all bodies, of course.
Easiest way to experiment is to set the image quality for RAW + JPEG fine. Then set picture control to Monochrome. This should give you a JPEG in B&W and the RAW image will contain color. You can compare the B&W JPEG to RAW file you convert.
I think it is best to shoot RAW and convert to B&W during PP.
There are two ways of working here. 1) In-Camera 2) Post Camera
With In-Camera you can make a lot of the same decisions as were made with film. You can use B&W filtration techniques to help bring out the specific tonal range you look for. But the disadvantage is that you are baking those decisions into the raw file. If you can think that way and you are very confident of how you pre-envisage the shot then this approach is as valid as any other and gets you the results you expect. In this case you might even consider getting yourself the B&W dedicated Leica Monochrom camera which has no bayer layer or anti-alias filter and gives ridiculously sharp images for the sensor size.
With Post Camera you have the option to change everything. This is always my preferred approach. I see in color and never did learn how to pre-envision in B&W. As such, while I know that adding red filters or yellow filters will change specific tones in the B&W I also want the flexibility of being able to change my mind later. Baking in the fitration at the shooting stage is just not for me. Plus some B&W process steps are better done on a colour raw file. Nik silver effects uses the colour file to help set the masking of the u-point selection. If the file was monotone, the u-point technology wouldn't work as well.
So for me the approach is to make the best colour image I can, then dial in the tonal ranges using selective filtration during post.