what is it on the 6D that i'll miss if i jump to the other camp?

kcbrown wrote in post #15059739
The outer points in the D600 aren't cross-type either. Those are all clustered vertically at the center.

If you need cross type sensors scattered throughout the frame (as opposed to clustered in the center or solely being in the center), your choices are limited to the 1Ds3, the 1D3, the 5D3, the 1DX, and the 7D. Nothing in Nikon's arsenal has cross-type points located anywhere other than the center area.

Honorable mentions should also go to the 50D, 60D, T4i- which all have 9 cross type AF points.. The denser arrangements of cross type AF points on the set listed by kcbrown are, however IMO, better in tracking in AI Servo---.. For AI Servo- the more the merrier.

My earlier point was that if you want to track moving subjects with AI servo- using a camera without cross type AF points is likely to end in disappointment. My suspicion is that even the 6D will be similar - although AI Servo is an option- it will not fare as well as cameras with all cross type af points. Furthermore, if you want to use AI servo- and that is important to you- center point for systems without all cross type AF points- or well- get one of the more sophisticated AF systems.

Here on POTN, I see it many times- people buy older cameras, or Rebels that have the orientation specific AF sensors- and well- are less than happy with its outcome on the outer points. Many fail to even understand that there is a difference and what it is.. It's like they have G.A.S.- but didn't bother to read & understand the specs- or in some cases- think that other features are going to offset the other weaknesses [LIke the FF Kool-Aid that is supposed to be the cure for everything]. Granted- I would tend to think that some actually have flawed testing- i.e. they might test a camera with cross-type af points- out in Single Shot- and see little difference between it- and say - a t1i/t2i/t3i.. Why? Well, in single shot- the outer AF points simply do not lock and give you the AF confirmation- and won't take the shot- till it gets focus lock! Had they tried it in AI servo- they might have or might not get pictures - in focus. It's more simply that they understand how One Shot works- but not how AI Servo works.

wayne.robbins wrote in post #15060132
Honorable mentions should also go to the 50D, 60D, T4i- which all have 9 cross type AF points.. The denser arrangements of cross type AF points on the set listed by kcbrown are, however IMO, better in tracking in AI Servo---.. For AI Servo- the more the merrier.

My earlier point was that if you want to track moving subjects with AI servo- using a camera without cross type AF points is likely to end in disappointment. My suspicion is that even the 6D will be similar - although AI Servo is an option- it will not fare as well as cameras with all cross type af points. Furthermore, if you want to use AI servo- and that is important to you- center point for systems without all cross type AF points- or well- get one of the more sophisticated AF systems.

This is all true within limits. Like I mentioned, I expect that not all line-type points are created equal. Most certainly, autofocus algorithms aren't created equal, and while the 1D2 and 1Ds2 may not have cross-type points anywhere but the (horizontal) center, it is apparently able to make use of both those and the line type points for tracking very effectively. Some here on POTN regard the 1D2 as being superior to the 1D3 for tracking, and the 1D3 does have cross-type points spread throughout its autofocus grid.

This is a very good point. Additionally, at least some (if not all) of the more advanced AI servo cameras (1D series, 7D, 5D3) allow you to tell the camera whether to take the shot in servo mode only if the camera thinks it has acquired focus, and with that setting there's a very good chance indeed that the shot will be in focus. The availability of this setting on the 7D is one of the main reasons I'm able to primarily shoot it in servo mode even when what I'm shooting is a non-moving subject. It works very nicely, because even if the subject isn't moving, chances are you are, even if only a little.

Hogloff wrote in post #15057526
... my suggestion would be to wait until the 6D is released and see if those outer points have been improved on. If not, you can then make your decision.

Excellent advice. People are always ready to jump the gun on theses things. No one has had the opportunity to see what the 6D can do. I think folks should hold off on condemning a product based on the stated spec and wait to see how it performs in practice.

One important aspect of a camera body that never seems to be mentioned much is how it feels in the hand. I personally have found Canon cameras to be more comfortable to hold. As an example, my hand fits great on the 60D and felt cramped on a Nikon D7000. I've read of other people who found the D800 uncomfortable to hold compared to the 5D Mark 3. Clearly a personal thing, but I think important if you're planning on holding a camera for a few hours.