36 frames were used to focus-stack this snowflake together, and here's a bit of a primer on snowflake photography for those curious how I make images like this:
Step 1: Black mitten. The background behind every one of my snowflake photographs is a home-made black mitten. The mitten serves as a contrasty background but also lifts the snowflake away from a solid background and acts as an insulator to keep it cold. Any dark woolen fabric will do!
Step 2: Fresh snow. Snowflakes will start to melt or sublimate (evaporate from ice without melting first) almost immediately, and if an hour goes by you'll have a hard time getting great pictures. I let the snow fall onto the mitten which rests on a table, and then I begin my search through the camera's viewfinder.
Step 3: Magnification. Snowflakes are tiny. They require some pretty significant magnification to fill the frame. This is accomplished with a special lens, the Canon MP-E 65mm 1x-5x Macro. This gets me up to 5:1 magnification which is powerful enough to photograph the larger snowflakes. (link for lens: http://www.bhphotovideo.com/c/product/183199-USA/Canon_2540A002_Macro_Photo_MP_E_65mm.html/BI/8924/KBID/10335/kw/CA6528MP/DFF/d10-v2-t1-xCA6528MP ).
If you don't have access to that lens, a combination of a macro lens with extension tubes can get you close, or reverse-mounting a lens in front of a macro lens can get you quite a bit closer. There are plenty of ways to experiment with extreme macro work.
Step 4: Light. I use a ring flash to light all of my snowflakes, and I can rotate the flash and position the camera to create glare on the surface of the ice - making the snowflake reflective.
The Next Steps: It's hard to describe the whole process here, because it's quite lengthy... but every image is shot entirely handheld. I'll only ever get a tiny slice of focus in any one frame, so I might shoot a few hundred images of the same snowflake and combine between 30-50 together to create the final image. I drastically overshoot to be sure that I haven't missed any slice, as there is no way of being certain I've got them all.
The editing process takes hours, but the result is always worth it. If you're curious to try photographing your own snowflakes, or the science behind how they form, check out the Sky Crystals book here: http://skycrystals.ca/ - I'm sure you'll enjoy it!