1st, Never worry about asking questions here. Thats what this forum is all about
Yes, I do use an inexpensive spring clamp to hold the flowers in place----But the clamp will often brake the flower stem and cause it to wilt faster, so I just place a small piece of tubing in the clamp, then place the flower stem in the tubing---Seems to work pretty well as long as there is little or no wind.
As far as getting skunked, well...thats always a risk with humming birds. Even if you have a lot of birds around, they may be more interested in fighting then they are in posing for pictures. Just like with most other forms of photography, some days are good, some days are great and some days are lousy. To reduce the number of lousy days I have with hummingbirds I do this:
1. Keep the feeder up as much as possible when not actively shooting.
2. When you replace the feeder with some type of flower system, charge the flower with sugar water; I use a vetrinary syringe. This keeps them coming back to the flower.
3. I normally only shoot with the flower up for about 20 minutes, then I replace it with the feeder. This gives you time to make adjustments, review your images etc, and gives the birds a chance to feed.
4. Try and pace your shooting. Its natural to try and snap as many shots as possible when the bird is hitting the flower or the feeder, but you don't want to terrorize the bird every time he comes to feed, if you do, they may not come back. I usually try and snap two or three shots when they come to the flower/feeder, Then on thier return visit, just let them feed without the flash. Just alternate this cycle and you will probably keep your birds coming back again and again---Patience is the key.
One note: If you have more than the one target feeder, take them down and hide them while you are shooting. This forces the bird to come to the target feeder. Also, Hide the extra feeders well. No matter where I put the extra feeders, the birds always seem to find them, even under the patio table, on the ground, etc. I resorted to hiding them in my barbecue grill and closing the lid. Don't forget to put the feeders back up when your done shooting.
Hope that helps,