Rebel xti and EF-S 55-250: manual focus trouble (bird photography)

[OceanHorizons]

Question: How can I improve my manual focusing skills for bird photography?

Back-story: a) I got a Canon EF-S 55-250mm IS for Christmas, b) I took a picture of a bird, c) bird photography obsession set in!

Recently I have been photographing birds at a local park (setting up bird-feeders in my yard is on my to-do list). I’ve found that the auto-focus (center-point) gets confused if there are any branches/etc between me and the bird. Manual focusing is proving to be a real challenge for me – my focus is really hit or miss (with a lot more misses) even though the bird looks sharp in the view-finder.

(On my Rebel XTi/400D the view-finder can be adjusted, but when I use auto-focus the focus in the view-finder and image are both sharp.)

So lately I’ve been taking several shots (if the bird doesn’t fly away) and just making tiny adjustments to the focus, hoping that something turns out.

For example: I was shooting this mockingbird through a chain-link fence. Not my best work but illustrates my problem. The second shot is “accidently” in focus, and I’ll do cropping/editing on it but I wanted to post both uncropped for comparison. (The focal lenght is the same, so does this mean I didn't really adjust it?)


Not focused:



Camera Canon EOS Digital Rebel XTi
Exposure 0.005 sec (1/200)
Aperture f/5.6
Focal Length 179 mm
ISO Speed 400



Focused:



Camera Canon EOS Digital Rebel XTi
Exposure 0.008 sec (1/125)
Aperture f/5.6
Focal Length 179 mm
ISO Speed 400



I’m really frustrated because I’ve blown the focus on some really interesting bird moments, and I don’t know how to improve my technique since the birds in the view-finder look sharp.
Thanks in advance for any advice.

[inkista]

Normally, I would tell folks to use liveview and 10x magnification for manual focusing, but the 400D doesn't have liveview capability.

I think your only choice is to up the iso and stop down to f/8 or f/11 to give yourself some more depth of field to work with. Or blow a lot of money on a longer lens. If your target is bigger, it's easier to hit it. You may want to consider saving up for an EF 70-300 IS USM or (big bux!) EF 100-400L f/4-5.6 IS USM. Birding tends to require at least a 400mm lens, because birds are very small and shy. Birding, like sports, is one of those things that can be demanding equipment-wise. Your only other alternative is to work on your field craft so that you can get closer without scaring them away.

You're also hampered by the fact that the dRebel viewfinder is rather small and dark to begin with, and it's designed for autofocus, not manual focusing. I'd say see if you can simply move to where the branch isn't in your way to confuse the AF system, and use the autofocus.

And possibly learning about backbutton autofocus to help you turn of autofocus hunting when you don't want it might be worthwhile, but isn't likely to make a huge amount of difference.

[OceanHorizons]

Thanks so much for the insight!

Originally Posted by inkista

I think your only choice is to up the iso and stop down to f/8 or f/11 to give yourself some more depth of field to work with.

I keep forgetting that I should use a smaller aperture - I have newbie-small-brain-syndrome .

Or blow a lot of money on a longer lens.

See, I told my significant other that a 400mm was a necessity!

Your only other alternative is to work on your field craft so that you can get closer without scaring them away.

That's more in my budget right now, so got a stack of birding books from the library... have some serious studying to do.

You're also hampered by the fact that the dRebel viewfinder is rather small and dark to begin with, and it's designed for autofocus, not manual focusing. I'd say see if you can simply move to where the branch isn't in your way to confuse the AF system, and use the autofocus.

Ah ha! So I'm not going crazy with the looks-sharp-but-turns-out-fuzzy stuff. I had it stuck in my mind that manual focus was better for bird shots, but I guess not with my current body. I think upgrading that is going to be a ways down the road, though. So for now I'd better improve my birding skills!

Thanks again for your help.

[inkista]

No worries. About four years ago, I was where you are now. The birding part is harder than the photography part, but possibly a little more fun. Highly recommend the SIbley Guide to Birds (not that you use it in the field--that thing is ginormous). The other Sibley books are good, too, but that one's the best for IDing North American birds.

As for the looks-clear, but picture turns out fuzzy stuff, you may also want to check that you've got the diopter adjustment on the viewfinder set correctly. But no, you're not going nuts. I've generally found the AF to be more accurate for me than manual focusing, unless I'm using liveview and 10x magnification.

And as for the 400mm? You know you want it.


Canon 50D. EF 400mm f/5.6L USM. iso 800, f/5.6, 1/640s.
White-Tailed Kite. Elanus leucurus (juvenile).

[OceanHorizons]

Thanks for the book suggestion - I'm looking for a good one to buy so I don't have to keep renewing the library's guides

Originally Posted by inkista

And as for the 400mm? You know you want it.

That shot is fabulous! (I've actually already drooled all over your flickr stream ) I'm saving my pennies...

[OceanHorizons]

Originally Posted by inkista

you may also want to check that you've got the diopter adjustment on the viewfinder set correctly.

I thought about that, but I did a couple test shots autofocusing on street signs with words on them, and the letters are sharp in both my view-finder and in the image - am I missing any advanced diopter adjustment techniques?

[inkista]

I'm flattered you like my Flickr, but you should see the gallery of Daniella T. Her posts on dpreview inspired me to buy the 400/5.6L and take up bird photography: http://www.pbase.com/zylen

Originally Posted by OceanHorizons

I thought about that, but I did a couple test shots autofocusing on street signs with words on them, and the letters are sharp in both my view-finder and in the image - am I missing any advanced diopter adjustment techniques?

Nope. That's pretty much it. Happy bird chasing!

[BCampbell]

inkista hits the nail on the nose that the viewfinder is really small for manual focusing, especially with long lenses on small subjects.

One more thing you might try is swapping out the focusing screen for something designed for manual focus. Either a microprism that will "pop" in-focus subjects with more contrast, or an aftermarket split-prism-esque one. Either will darken your viewfinder but make it a lot easier to tell what's in focus and what's not.

[inkista]

Um... on a lot of those after-market focus screens the prism collar blacks out with an f/5.6 lens as well as making the viewfinder darker. This is the main reason I have to swap my Katzeye (non-OptiBright) in and out of my 50D when I go birding with the 400/5.6L with the 50D.

And the dRebels--it's extraordinarily easy to damage either your focus screen or the spring-loaded bracket that keeps it in place when you swap them. I swear that plastic gets a scratch if you so much as breathe on it. But then I'm a bit of a klutz. I do vintage fountain pen repair, and I was still sweating bullets In the one and only attempt to clean the focus screen on my XT. And I ended up scratching it. It was "fixed" by being replaced by Canon service when I sent the XT in to them for a power board failure.

The 50D took away all my worries by having interchangeable focus screens, so I can just unlatch a door, and use a tweezer-like tool to safely pop focus screens in and out without ever touching the face of one.



With a 40D/50D/60D or 5D if you're using fast manual focus lenses, I'd say swap the focus screen. With a dRebel or 7D, it's a matter of what your comfort level is with finesse repairs. If you repair watches on a regular basis, it's probably a cakewalk. Me, those shims/wires are a little too fragile for comfort, and if I have to snug down a metal spring against a plastic surface, chances are good I'm going to scratch the plastic surface before I get the job done.

[BCampbell]

Ah, I didn't know the screens on the Rebels weren't as easily interchangeable as the xxD/5D.