5d mkII vs 50D in terms of AF

[contrastny]

I am looking to upgrade from my 50D, especially with the price drop on the 5D mkII. I haven't used the 5D II, but one of the main complaints I have heard is the AF. Is it better or worse than the AF on my 50D?

I mainly shoot landscapes, but I occasionally use AF for other subjects. The 5D II will be a great upgrade and I'll get it with the Zeiss 18mm.

[neuroanatomist]

The center point on the 5DII is just about as good as the center point on the 50D.  The off-center points are not nearly as effective as those on the 50D.

[Fab_Angilletta]

it's basically the same AF but your Zeiss will be MF only.
for occasional AF, 5D mark ii is more than capable, at least as good as your 50D.

[MartinvH]

The center point on the 5DII is just about as good as the center point on the 50D.  The off-center points are not nearly as effective as those on the 50D.

How does the 5DII AF compare to the T2i/550d or similar T3i/600d ?
Similar centre point ,lousy off-centre points ?

[contrastny]

it's basically the same AF but your Zeiss will be MF only.
for occasional AF, 5D mark ii is more than capable, at least as good as your 50D.

Yeah, I was just curious about the AF for my other lenses.

[Mt Spokane Photography]

For landscapes, portraits , and general center point usage, I find it to be very good.

In terms of AF accuracy of the center point, its extremely accurate.

In low light, it matches or exceeds my 1D MK III and is better than the 1D MK IV

Outer points and subject tracking are its weak points.

The lens you use is a big part of AF speed, but tracking, low light, point selected, and accuracy vary by model.

[neuroanatomist]

How does the 5DII AF compare to the T2i/550d or similar T3i/600d ?
Similar centre point ,lousy off-centre points ?

The individual points are similar in terms of performance between 5DII and the Rebel/xxxD cameras.  The center is cross-type with one f/2.8 line and one f/5.6 line, outer points are single-orientation f/5.6 (vs. the 40D-60D cameras where the center point is a dual cross with f/5.6 orthogonal lines and f/2.8 diagonal lines, and the outer points are f/5.6 crosses). 

However, the relative spread of the 5DII AF points is worse - in fact, the 5DII has the least AF point spread of any current Canon camera (including the T3/1100D).  All of the others manage to get an AF point at least somewhere in the approximate neighborhood of a rule-of-thirds intersection, but the 5DII doesn't come close. 

[wickidwombat]

For landscapes, portraits , and general center point usage, I find it to be very good.

In terms of AF accuracy of the center point, its extremely accurate.

In low light, it matches or exceeds my 1D MK III and is better than the 1D MK IV

Outer points and subject tracking are its weak points.

The lens you use is a big part of AF speed, but tracking, low light, point selected, and accuracy vary by model.

I agree the center point is accurate, I do think using an f2.8 or faster lens is essential on the 5d2

but i do find my 1d3 AF to be considerably better in every respect than the 5D2 especially using f4 lenses such as the 24-105 f4L or the 300 f4L

[briansquibb]

I must be the only person that uses the centre point and FL recompose. Brillian method, especially in low light

[wickidwombat]

I must be the only person that uses the centre point and FL recompose. Brillian method, especially in low light

No I use this method too, works better using back button focus too

[neuroanatomist]

I must be the only person that uses the centre point and FL recompose. Brillian method, especially in low light

No I use this method too, works better using back button focus too

Yes, I use it, too. It works just fine with a deep DoF, like f/4. But at f/2 and wider, it results in back-focused shots.

[Mt Spokane Photography]

Focus and recompose works at smaller apertures where the error in AF accuracy that results is hidden in the depth of field, but get up close with a 35mm L at f/1.4, and it will give you fuzzy images due to focus errors..

[wickidwombat]

does anyone use the EG-S focus screen on a 5DII with f1.4 lenses to MF? I'd be interested to hear their esperience with them

[briansquibb]

Focus and recompose works at smaller apertures where the error in AF accuracy that results is hidden in the depth of field, but get up close with a 35mm L at f/1.4, and it will give you fuzzy images due to focus errors..

I think you will find that the accuracy depends on the radius, the distance moved and the contour of the subject.

Like everything else - know your tool and you can use it in the right way. With the 5D2 you can take a step back to get the focus points to cover the right point and use MP for the crop.

There are always exceptions - I am sure that we could find something that the D3X and 1DX cant do as well.

[The Bad Duck]

does anyone use the EG-S focus screen on a 5DII with f1.4 lenses to MF? I'd be interested to hear their esperience with them

I do (5D mkII + 35/1.4; 50 /1.4 and 85 /1.. With the EG-S you have an easier time telling when your focus is off. But it really does not help that much when it comes to telling if focus is spot on @ f/1.4. Live view @ 5x or 10x is the only way to really know you got it right at those apertures. Of course, that might not be possible to do in actual shooting.

Also your viewfinder gets darker and that makes it harder to handle f/4 zooms in low light.

A way to get higher odds of getting your focus right is to have a flash to help with infra red AF-assist and use the focuspoint where you want your picture sharp - even if it is not the centre point.  You don´t have to fire the flash, but the AF-assist really helps out. I can´t figure out why there is no AF-assist in the body. I would love that for low light, no flash situations since an external flash makes the camera heavier and it also makes the camera bigger and more intimidating to some subjects. Finaly its harder to keep your camera haning over your shoulder at a party with a flash attached.

Also, something Im still trying to get used to, is that the slightest movement from you or your subjekt might mean you loose focus. FF and fast lenses is demanding in a way I did not understand when I upgraded from my 30D and f/4 zooms.

So - go ahead and use the EG-S, it does help but does not do wonders.