squizza
Eeyore
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100 200 300 400
f4.5 f5.0 f5.6 f5.6
So judging by this it would lose autofocus at 300mm
Birds in flight....
- Thread starter jerry12953
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100 200 300 400
f4.5 f5.0 f5.6 f5.6
So judging by this it would lose autofocus at 300mm
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- Trev
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Your right, apart from the 1 series, autofocus wont work above f5.6. A 100-400 at 400mm is f8. As has been said, there is a trick of taping 3 of the pins to make the AF work, and to a point it does work, but its desperately slow to the point of being unusable in my experience. Possibly it will work work on a stationery subject where you can wait, but BIF, no, its just not going to work anywhere near fast enough.
EDIT: Sorry Tim, I crossed with your post
Sorry to jump into the thread but I can never nail BIF pictures... im going to try the backbutton AF but my camera never really leaves the evaluative metering... could you explain this in a more simple term?!
Thanks.
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Not really, at least not without going over the same old ground I have already covered far too many times in posts in this forum. Have a look at these threads/articles and see if they help.....
http://www.talkphotography.co.uk/forums/showthread.php?t=158332
http://www.talkphotography.co.uk/forums/showthread.php?t=226793
http://www.talkphotography.co.uk/forums/showthread.php?t=115623
http://www.kodak.com/cluster/global/en/consumer/products/techInfo/af9/index.shtml
http://www.cambridgeincolour.com/tutorials/camera-metering.htm
Cheers Tim, very helpful.
I was going to ask a cheeky question about back button AF but fear I may get the same answer.
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If your subject is indeed moving evenly across your field of view then Mode 2 IS may offer an advantage, but if there is any combination of vertical and horizontal motion in your subject, such as landing or swooping or flying overhead then any IS mode you use will fight with your intended tracking of the bird. If you use a sufficiently high shutter speed then in my opinion the value of IS is questionable and may even have negative consequences.
As far as shutter speeds and IS are concerned, there is an interesting article by Thom Hogan about Nikon's VR system, which adises against using VR when shooting at high shutter speeds. My own experience leads me to suspect that Canon's IS system suffers similar limitations.
http://www.bythom.com/nikon-vr.htm
People can shoot fabulous BIF images with the unstabilised 400mm f/5.6L prime. If they don't need IS in order to achieve their results it follows, as far as I can tell, that IS is not a requirement when shooting BIF with a 100-400 either. It's a different story if you are purposely shooting at low shutter speeds, or have a specific situation such as a bird approaching head on, but to be prepared for any eventuality I think IS is best left off.
Here's an example and 100% crop from my 100-400, hand held at 400mm, 1/800, wide open, no IS, no edits. It isn't pin sharp, but I don't see signs of shake. In my opinion the odds of IS improving this shot are zero. The probability of IS doing some harm is far higher.
I do have sharper examples, also without IS, but this is the first image that was handy.
As far as shutter speeds and IS are concerned, there is an interesting article by Thom Hogan about Nikon's VR system, which adises against using VR when shooting at high shutter speeds. My own experience leads me to suspect that Canon's IS system suffers similar limitations.
http://www.bythom.com/nikon-vr.htm
People can shoot fabulous BIF images with the unstabilised 400mm f/5.6L prime. If they don't need IS in order to achieve their results it follows, as far as I can tell, that IS is not a requirement when shooting BIF with a 100-400 either. It's a different story if you are purposely shooting at low shutter speeds, or have a specific situation such as a bird approaching head on, but to be prepared for any eventuality I think IS is best left off.
Here's an example and 100% crop from my 100-400, hand held at 400mm, 1/800, wide open, no IS, no edits. It isn't pin sharp, but I don't see signs of shake. In my opinion the odds of IS improving this shot are zero. The probability of IS doing some harm is far higher.
I do have sharper examples, also without IS, but this is the first image that was handy.
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Cheers Tim, very helpful.
I was going to ask a cheeky question about back button AF but fear I may get the same answer.
If you have a question that is not addressed in POST #10 of this thread, or elsewhere in the thread then please feel free to ask and I'll answer if I can.
Its more clarification really...
Does back button mean that I can see what I want to photography, line it all up etc etc like normal and then when I push the back button it locks the autofocus? So to take the picture I just push the shutter? Using your example of the bird flying off... if its there perched, I line it up with the AF point, push the back button and then it flies off... is the focus locked so I just follow it in the view finder or would I have to press and hold the back button?
Appreciate the help... a lot!
OP
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- Jeremy Moore
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Yes, I take your point.
And on a 5D2 use the 400mm and crop!
But I'm sure a lot of the blurb I've seen about this lens (esp on ebay) says that it is compatible with both canon tc's.
Edit ; I dont mean "blurb"; I mean blurb.
Edit edit: What ever does blurb mean anyway. Funny old word......trails off into the distance.........
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The camera will only focus while you are pressing the AF-On button. So in your (my?)scenario you would need to continue pressing the button in order to track the bird.
As soon as you release the AF-On button the camera ceases to AF. That is the whole point of using back button focusing You can focus when you want to and stop focusing when you don't. The shutter button can be freely used to take the shot whenever you like, without screwing things up by making the camera focus where/when you don't want it to.
As soon as you release the AF-On button the camera ceases to AF. That is the whole point of using back button focusing You can focus when you want to and stop focusing when you don't. The shutter button can be freely used to take the shot whenever you like, without screwing things up by making the camera focus where/when you don't want it to.
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Compatible means it will physically fit. There are some Canon lenses which are not compatible with their own TCs because they will not physically fit together, due to the protruding lens elements within the TCs. Kenko TCs and possibly other brands have broader compatibility with more Canon lenses than Canon's own TCs becaus their design keeps all lens elements within the TC without protrusion.
AF is a separate issue, and it all pretty much comes down to your final aperture value when adding the TC to the lens. In that regard a Canon 1.4X is no better or worse than Kenko or any other brand of TC. Ditto for the 2X TCs.