The hummers found my bottlebrush plants last year, and after I added a feeder similar to yours, there was a steady supply of birds. All I had to do was put a lawn chair out about 25 feet from the plants/feeder (with sun at my back) , sit very quietly and move slow when they showed up. Seems like 1/2000 sec shutter speed was good for freezing wing detail, 1/320 for blurring wing motion. If they've found your feeder, maybe put a potted Lantana plant close by as an extra attractant, and pay attention to whether there's a particular time of day they show up. They got so plentiful I was about ready to roll up a newspaper and shoo the little pests away! Happy Hummin' !