Tried my hand at snowflake macros for the first time last night. I've read that some people set up a special rig and move snowflakes onto it, but I just wanted to shoot the snow "in situ", as it fell down. It was about -12C, with no wind and large flakes gently falling down at the end of a major snow storm - ideal! So I strapped on the Tamron 90mm, the Raynox 250, 50mm of extension tubes, and my homemade telescoping Pringles flash diffuser, and headed out. I just looked for interesting formations, and shot everything handheld. Oh, and I also borrowed a lamp from the living room so I could focus.
This combo give 2.6:1 macro, and I added some cropping in post (varies, but not a lot). Though the shots were a bit under exposed and required some post, I'm pretty pleased with the results!