Long Billed Dowitcher
Most of the time auto focus works rather well, allowing us to focus on the subject that we want it to, but in what situations is auto focus not effective? If auto focus worked for every situation, and always did what we as photographer wanted then manufactures wouldn't waste their time including manual focus rings. I had a situation two days ago when I was out shooting where due to poor contrast on a subject in reasonably bright conditions the auto focus system couldn't achieve decent focus, and not without trying either. In one case, I took over 30 shots of a given subject, in this case a Sandhill Crane, and found that the auto focus system could not get decent focus, which was frustrating to say the least. In fact I thought there might be something wrong with the auto focus on my camera, or the lens, but after shooting some other birds I found that auto focus was working just fine. In my case, I just had to give up taking photos of the subject that I was trying to photograph, as the subject was too far away to accurately manual focus.
Its funny, but sometimes when you are out taking photos you don't think that the photos are taking would be very good, masked by the small LCD on your camera. Not that the 3" LCDs on modern digital cameras are small, but even compared to say my 13" notebook screen it is hard to see the details. Thankfully the zooming feature on camera allows you to check focus, otherwise we might as well just take twice as many shots because other than in situations where focus was missed entirely we wouldn't be able to tell. That's my ramble for today.