Hi, I'd like to take some outdoor daytime photos when the snow is falling and be able to capture the snow falling as part of the picture. Some of the pictures may be portraits with a shallow depth of field, while other photos may be more landscape or just simply have a larger depth of field. How would you recommend that I do this? Is it all about the shutter speed irrespective of my aperture for DOF? If so, what shutter speeds would be typical to capture falling snow? Also, does it matter where and what I'm focusing on in order to capture falling snow (since likely my focus will be a person or object or landscape primarily and not the snow)? Do I need to increase the ISO since it won't likely be a sunny day (other than a lot of white from the sky and snow)? I'm shooting with a Nikon D90 DSLR if this is relevant and I can give you the lens information if needed (unless you have any good lens suggestions for this)? Finally, what would I do if I wanted to capture falling snow at night time? Many thanks!