Blenheim Orange Loc: Michigan

While the Canon SX50 super zoom can be useful in the field, it struggles when trying to fill the frame with a 2-6" subject at 5-10 feet away, because auto-focus won't work under those conditions.

I wonder if the other super zooms, like the Nikon P series, Nikon B700, Panasonic Lumix FZ80, have a similar issue.

Minimum auto-focus distances at various zoom amounts on the Canon SX50 -

24mm - 0"
100mm - 2"
135mm - 9"
200mm - 14"
300mm - 30"
400mm - 60"
600mm - 80"
800mm - 60"
1200mm - 45"

Note that those are (roughly) the minimum distance at which the auto-focus works, not necessarily the minimum focusing distances. Also note that the focal lengths are "35 mm equivalent" figures as marked on the barrel of the lens. Who knows how accurate any of that is, but that does not matter for this test.

I added in the variable of filling the frame at each of the focal lengths, whatever distance that dictated, since on real life that is what we want to do. Testing that, at 300mm-600mm zoom amounts, you cannot fill the frame with a 1-6" subject and get auto-focus to work. In casual use, that might not seem like a problem - just zoom out, move in closer until you can fill the frame, and then focus. But if you are trying to shoot, say, butterflies or other insects or small critters, that 60-80" range, which means 300mm-600mm zoom to fill the frame, occurs very frequently. Even with plants and relatively stationary subjects, it is a pain to have auto-focus fail in that middle range. You are forced to zoom out and move very close or zoom in and move farther way.

Mike

letmedance Loc: Walnut, Ca.

When using the Super Zoom cameras to shoot small objects I always use a center spot for focus, at 1200MM on my Lumix I often find it difficult to focus on insects if I do not use spot focus.

Blenheim Orange Loc: Michigan

Thanks. At 1200mm the SX50 has no problem auto-focusing on anything 45" away or farther. I am nit talking about difficulty in getting auto-focus to work, which can be a problem in low contrast scenes for example, but rather certain conditions under which auto focus never works. As I said, those conditions are trying to fill the frame with a 1"-6" subject at 5-10 feet away (I tested a 1" object since I first posted this. The smaller the object the worse the problem.). I would love to know how your Lumix performs at that task. Does auto-focus work when you zoom at different amounts between 300mm-600mm and then move to fill the frame with a small object?

Mike

letmedance Loc: Walnut, Ca.

Often I have to zoom out until I can establish focus on the object then zoom back in until the frame is filled.
John

Blenheim Orange Loc: Michigan

Yep. But for small objects, filling the frame, at 4-7 feet or so, which means 300mm-800mm the equivalent focal length, auto-focus doesn't work. Sure you can walk away from your subject - while zooming! - until auto-focus works, but that kinda defeats the purpose of a zoom, Sure you can get 0-10" from the subject and the auto-focus works, but if it is a live subject you just scared it off.

Mike