for me the use of flash is one of the tools I always consider.
I have posted this shot many many times, but it serves as an excellent example of what can be achieved.
this was shot with my *istD, at ISO 400, with a SMC-Pentax 300mmF4 lens plus 1.7x AF TC.
I used TTL flash which the *istD supports, and shot with manual exposure, set to about -2 stops, with the natural light, the flash then highlights the subject and the background falls off into the dark shadows.
Depending on lenses and cameras, you can't always take this shot because only the *istD and DS support TTL flash, making older lenses very useful on these bodies.
I also use my other newer bodies (K10 and K7) with my sigma 70-200F2.8 and any combination of 1.4 and 2x sigma TCs with flash, in similar conditions.
Flash freezes the subject, with durations at around 1/1000. clearly you can't get the light for that kind of shutter speed any other way.
flash is also not that disturbing to birds, it is like lightning, or bright reflections.
As for equipment, I use Pentax flashes, AF500FTZ on the *istD and AF540FGZ on the K10 and K7.
I have better beamers for both, but generally don't use these on small birds. The chickadee was shot at almost the minimum focus distance for the 300F4, (about 15 feet) and at that distance, no flash focusing aid was needed to get the illumination. I use the better beamer for bigger birds like herons, where due to the size of the bird, you are naturally further away, and since flash falls off badly with distance, the better beamers help.
I also consider boosting ISO. You will note that my shot with the *istD was at 400 ISO not the base 200. I tested the camera when I gfot it and determined there was virtually no loss of IQ by shooting at 400ISO over 200, so for long lenses I shot at 400.
I have shot without flash up to 1600 ISO on my K10D and K7D and posted those results also. You shoot with what you have, if you don't have a flash handy, push the ISO, if you have a flash, use it.
Fast lenses don't alays make the shot, because you need to stop down for depth of field occasionally,, and best IQ is usually stopped down 1-2 stops, although my SIGMA APO 70-200F2.8 EX (non DG non macro) is a great performer wide open
Last edited by Lowell Goudge; 06-23-2010 at 05:26 AM.