Birds in flight....

[squizza]

So does this mean that with the x1.4 TC and 100-400 zoom AT 400mm I would lose autofocus, or at any focal length?

100 200 300 400

f4.5 f5.0 f5.6 f5.6

So judging by this it would lose autofocus at 300mm

 

[Trev4]

So does this mean that with the x1.4 TC and 100-400 zoom AT 400mm I would lose autofocus, or at any focal length?

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

 

[a lex]

My metering/exposure approach for BIF would be to set a manual exposure either by....

- spot metering from my palm at + 1 1/3 if my scene included (partially) white birds;
- spot metering from my palm at + 2 1/3 if my scene only contained neutral or dark subjects/surroundings;
- spot metering the brightest part of the subject/scene (possibly the sky, if whiteish, or a swan's brightest feathers) at +3
- look at the scene before me and spot meter from a tone that I felt I could place reasonably accurately where it belongs within the camera's dynamic range

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.

 

[tdodd]

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.

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

 

[dubcat]

Tim - you recommend disabling IS for BIF shots. Can you explain why? I thought mode 2 on the 70-200 (the panning mode) would be perfect for this...

 

[a lex]

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.

 

[tdodd]

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.

 

[tdodd]

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.

 

[a lex]

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!

 

[jerry12953]

Further to all the above, if you want to turn your 400mm f/5.6 lens into a 560mm f/8 lens you can appreciate the difficulty achieving acceptable IQ, sharp and free of both noise and shake, when gunning for BIF with a handheld lens. On a camera like the 7D you will already be encroaching into diffraction softening territory, and with a target shutter speed of probably 1/1600 or more you'd need at least 400 ISO in bright sunshine in order to achieve that speed. In poorer light you might well find yourself at 800 or even 1600 ISO, and by that point your larger but noisier image will probably gain you little or nothing. Considering the loss of AF as well it is an option I prefer not to choose. Better a sharp, clean image at 400mm than a fuzzy, noisy image at 560mm.

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.........

 

[tdodd]

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.

 

[tdodd]

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.

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.