...from an excellent birder who provided the following guidance (I have the 70-300, thus the reference in the first paragraph):
"OK, let's start off with the gear. I think that the 70-300G is a great lens, My friend Eric (Zamac on Dyxum) has one and he uses it with a Tamron 1.4TC for birding. When he and I have been out shooting, he doesn't seem to have much difficulty locking focus and getting excellent results. It's not as sharp as the 300/4, but it's not that far off. Considering it's a zoom, rather than a prime, I think it's a great performer.
Next, your problem with blown whites. I meter using centre weighted average, and this generally gives me a good balance between whites and blacks. I may have to juggle the exposure between -0.3EV and 0EV, but it's not that far off. I've also been experimenting with manual exposure lately. Find a nearby white(ish) subject that's in your general "line of fire", and meter off that. A common setting would be 1/1250, ISO 400, F6.3 to 8. The shutter speed should be above 1/1000 sec to avoid motion blur and hand shake.
Do you shoot RAW? I do get blown whites as well, however shooting RAW is a big help. I use PS CS3 ACR to develop my shots. The exposure adjustment and highlight recovery feature is excellent. I like IDC as well, but it just runs so slow on my 3 y.o. PC - so frustrating).
When I was learning BIF, I used to look at the EXIF data in a lot of shots that others had posted. Do you use an EXIF viewer (such as FXIF)? I leave my EXIF data intact when posting, so find a shot you like and check out my settings (bear in mind that it may have been processed in RAW and the initial settings may have been a bit off). Also look at LuisV and Gil's work. I'm pretty sure they leave their EXIF data intact as well.
While I think of it.... I shoot either early morning or late afternoon. When the sun is high in the sky, the lighting is too harsh. Harsh lighting leads to blown whites. Summer lighting is also very harsh. I find the other seasons better because the sun is lower in the sky.
I use the histogram on hte A700 quite a bit when I'm birding. I've found that if you get the "blinkies", the shot is way blown, and recovery may be difficult. Avoid "blinkies" at all costs!
As far as focussing goes, I use spot continuous focussing. I lock onto the bird when it's around 50 metres/yards away, and then continue to track it until it's close enough to shoot. Pelicans are great subjects - they're big, slow and fly relatively straight. Most of my early practice was on these. Seagulls are also good for practive, but a bit harder. If they fly straight at me, I'm struggling to get a shot in focus. The A700 AFC doesn't seem to handle this situation very well. The Canon 1D's have better tracking and predictive auto focus. I think Gil and LuisV uses wide area AF. I've tried it, but have found that it will lock onto distant trees etc instead of the bird. On this subject, I suggest you find a clutter-free spot to do birding. Few trees and obstructions is good.
The focus limiter on the 300/4 is excellent. Sometimes I forget to set it - I know straight away because focus lock is very sluggish. However once it's set (at around 7-10metres), it locks on pretty quickly. I shoot with Canon 30D/40D users sometimes and they're amazed at how quickly the A700/300/4 locks onto the subject.
Anyway, I hope this helps. Birding can be frustrating at times, but it is rewarding when it all comes together. I'm still learning "new tricks" too. I still come back with 200 shots and delete the lot because they're no good."
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