Hey Ron, thanks for the warm welcome! I appreciate your compliments on my work, and I'm always happy to talk about techniques.
- The snowflakes will melt when shooting at warmer temperatures, within 5 degrees C of freezing. ambient heat and heat from the flash both play a part, so you have to work quickly at those temperatures. The biggest snowflakes happen to form when things get a little colder, but you still have to work quickly. While the snowflakes are less likely to melt, they will still evaporate over time. Called sublimation, a snowflake will return to thin air be switching from a solid directly to a gas. You have about a half hour to photograph a snowflake before all the details become rounded and less interesting.
- I use a black woolen mitten for my images, and it usually stays outside. When bringing it outside, simply waving it around for a bit will help it cool off, and when snowflake fall on top they usually only make contact with a few fibers, so there is less of a chance for heat transfer.
- The wind can cause problems. I don't use a wind screen of any kind, but the close proximity to the crystal often blocks a lot of it. Heavy wind doesn't just make it difficult to photograph the snowflakes, it also produces less "perfect" crystals and you have less material to work with. The best snowfalls are the ones with low wind and moderate accumulation at around -15C.
- It's always best to put your camera in a plastic bag when bringing it back inside. This will prevent water vapour in the warm inside air from condensing on the camera. Instead, it'll condense on the plastic bag. In practice, I don't do this as often as I should. It should be done all the time, but I have had no damage as a result.
We've had a few snowfalls here in Barrie, Ontario so far, one of which was good for photographing. We'll usually end up with a dozen or so good snowfalls through the winter, and I can get plenty of specimens from each one. Because of the time involved in editing, I even still have some from last year that I haven't gotten to yet.
By the way, most of the questions you asked are answered in the book.