I think converting an image to Black and White is a very subjective thing. I tend to do it when there is high “structure” in an image- because losing the color is replaced by drawing a viewers eye into the details or texture of the photograph. I use Silver Efex Pro for almost all of my conversions, I find that it typically nails it on one of its presets (“High Structure”) is my favorite preset of the bunch. it is fun to experiment with filters… only the hours in a day will restrict your playtime (…and kids, and work, and the dog 🙂
Anyway, back to Antelope Canyon… come walk the wider part with me… in Black & White…