I’m going to be looking at converting the raw files to colour and then to black and white. The examples all used Corel Paint Shop Pro for raw conversion and subsequent image processing. You could use other raw converters and photo editors just as well.
In my own work I often apply some fairly hefty curves and adjustments to my black and white images. Posterisation can be a real problem if you are working with 8-bit images (such as from JPEGs). One way to reduce the risk is to work in 16-bit where you have more data to play with.
Back to the sky and clouds.....
I compose and take the picture just as if I had black and white system in my camera.Well not quite, I might select a filter, maybe a light orange filter – red often looks too much like moonlight.
With digital I can still apply the equivalent of a coloured filter for black and white, but I’m going to do it later with Corel Paint Shop Pro. I also have the advantage of changing my mind if I decide, for example, that a yellow filter would have been better.