wickerprints
Offline
• • • •
Upload & Sell: Off
|
cogitech wrote:
Static subject, ample light, centre focus point directed right on top of the subject. Fail, fail, fail, fail....
If this is a matter of me not knowing how to use AF, then please tell me how I should have tricked the camera into focusing properly.
On second thought, don't bother. I won't be using it again for a long, long time.
As I previously mentioned, I am by no means a huge fan of AF. So please try to understand that what I'm about to say here is not meant as a criticism of your technique or knowledge level.
Certainly you must know that AF requires a certain level of subject contrast within the AF field in order to function. For example, pointing the camera into a cloudless sky will cause AF to fail, even though there is plenty of light.
Second, the AF point is not truly confined to the rectangle that shows up in the VF. And if you have AF point expansion on, this can impair AF accuracy under certain conditions that are related to the contrast issue I mentioned above.
When I use AF, I don't just try to point the camera at the spot I want to be in focus. Depending on the subject, I will sometimes look for a spot that is as close as possible to being the same distance away, but has higher edge contrast, in keeping with the above. Otherwise, if I target a low-contrast area, the AF system may not find the desired focus, or even worse, it may lock onto the wrong portion of the subject and confirm the incorrect focus, leading you to believe it is correct. This is why AF point expansion is not always a good thing--assist points will try to find subject contrast in the scene that you want to ignore, such as the branches in your example.
Speaking of your example, instead of pointing the AF directly at the bird, I would have pointed it at the boundary between the bird and the background sky. This would carry a small risk of backfocus, but with some experience, I find this helps out a lot.
I dunno. Take it for what it's worth. If you choose not to use AF ever again, then that's your decision. It's not going to have any bearing on how I, or anyone else, shoots.
|
