As I said in Monochrome pictures and the writer: a heads-up, I think that black and white photos can allow you to see more detail than their colour counterparts.
As an illustration of what I mean, compare and contrast the following two pictures. Both depict the reflection of a river in a bridge -- which in itself is unusual.
Which do you think is better? I think the monochrome one shows more detail.
What's this to do with writing? For me, the monochrome version is more detailed, more stimulating and more dramatic, all of which would inspire me me to write.