Canon 5D mk2 Auto Focus accuracy

kardo

kardo

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Kardo Ayoub
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Hi everyone,
My girlfriend wants buy a fullframe DSLR, for good bokeh and high iso, she is thinking about the 5D mk2 with the 24-105 L IS lens.
I know that is has less focusing points than the Nikon D700, but she doesn't do any action photography so that shouldn't matter very much.
I am reading online that the 5D mk2 still uses the old AF system, my question is wether the AF system is fast and accurate compared to other cameras, she mainly shoot street, landscapes and candit portraits, mainly kids, also weddings.

If you have any experience with this camera could you please tell me how good the camera is and if the the AF is not off putting.

Opinions regarding this lens is also wellcome.

Many thanks.
 
The 5DMk2 is no 1 Ds series camera and at less than a third of the price you would not expect it to be. For the types of photography mentioned it will excell.

Lens choice will also play a big factor in the AF speed, some are slower than others and my 85L is purportedly a slow performer, whilst my 135L is very quick.

The 24-105L is a solid performer and focusses relatively quickly.

Some images here, some posed some candid!
 
If you want super-dooper focusing, the Nikon wins, but those subjects are not very demanding in that department and the Canon 5D2 has other virtues.

Also, Nikon has no answer to the 24-105L. It's a brilliant general purpose lens, and a good enough reason in itself to go for the 5D2.
 
I'm told that the 5D2 has an AF system that's a little better than a 5Dmk1, which I now own, having moved on from a 1D for weight reasons.
Have to say that when I first got the 5D, I was less than impressed with it's AF, but that's because I was trying to use it as I would my old 1D. After some experimentation, what I found was that:
- The 5D needs better glass for more accurate AF. I had previously used a 50mm F1.8 on the 1D, and that was fine. On the 5D, the AF inaccuracy of the 50mm was somewhat highlighted and I ended up replacing the 50mm with an 85mm F1.8.
- The outer AF points are pretty much rubbish for moving targets. If you need to use AI Servo (which I do), the centre point is the only AF point worth using. The good news is that on centre point, the hit rate for AF is actually really good. Just means that you end up doing more cropping during processing.
- For static targets, the AF is more than adequate whilst using any of the AF points.
Now I've adjusted to the 5D, I have no qualms with the AF, which now has a very high hit rate, and of course that lovely image quality that FF brings to the party.

In short, the AF in the 1D is so good that you can take serious liberties with how you use it and accompanying kit. The 5D needs better ancillaries for moving targets. For landscapes it's spot on.
 
One thing to bear in mind with this discussion is that the 24-105 will not allow the 5D2, or any other body for that matter, to take advantage of the higher accurracy AF points. The lens needs to be f/2.8 or faster before the facility becomes available.
With an f/4 lens then the target focus will simply be within the depth of focus (not field) whilst an f/2.8 lens (or better) will be targetted to within 1/3rd of the depth of focus.

Bob
 
Mr_Sukebe said:
I'm told that the 5D2 has an AF system that's a little better than a 5Dmk1, which I now own, having moved on from a 1D for weight reasons.
Have to say that when I first got the 5D, I was less than impressed with it's AF, but that's because I was trying to use it as I would my old 1D. After some experimentation, what I found was that:
- The 5D needs better glass for more accurate AF. I had previously used a 50mm F1.8 on the 1D, and that was fine. On the 5D, the AF inaccuracy of the 50mm was somewhat highlighted and I ended up replacing the 50mm with an 85mm F1.8.
- The outer AF points are pretty much rubbish for moving targets. If you need to use AI Servo (which I do), the centre point is the only AF point worth using. The good news is that on centre point, the hit rate for AF is actually really good. Just means that you end up doing more cropping during processing.
- For static targets, the AF is more than adequate whilst using any of the AF points.
Now I've adjusted to the 5D, I have no qualms with the AF, which now has a very high hit rate, and of course that lovely image quality that FF brings to the party.

In short, the AF in the 1D is so good that you can take serious liberties with how you use it and accompanying kit. The 5D needs better ancillaries for moving targets. For landscapes it's spot on.
Click to expand...

The only apparent difference between mark I and II is that the latter has 6 AF "assist" points as well as the 9 AF areas...
 
Canon Bob said:
One thing to bear in mind with this discussion is that the 24-105 will not allow the 5D2, or any other body for that matter, to take advantage of the higher accurracy AF points. The lens needs to be f/2.8 or faster before the facility becomes available.
With an f/4 lens then the target focus will simply be within the depth of focus (not field) whilst an f/2.8 lens (or better) will be targetted to within 1/3rd of the depth of focus.

Bob
Click to expand...

Good point about about the improved accuracy of f/2.8, and I understand the comment about depth of focus as opposed to depth of field. I guess that is the only way the camera can work, since the AF sensors are in the body.

But what are the parameters for acceptable depth of focus, or more to the point, how does that relate to depth of field which is actualy all that's relevant here (since you can't move the sensor)?

Depth of focus changes differently to depth of field - it increases with higher f/number, but also increases with focal length, so I guess it's difficult. But does anybody have a comment on that?
 
HoppyUK said:
Nikon has no answer to the 24-105L. It's a brilliant general purpose lens, and a good enough reason in itself to go for the 5D2.
Click to expand...

Eh? 24-105 is like a skoda. You know it's well made underneath, but it's just a bit dull! And let's not forget it's only f4. To the OP I'd say get the 5D Mk2 but I wouldn't race out and buy it with a 24-105. Put it this way, I wish I'd got the 24-70 everytime I shoot a wedding, not that I use the 24-105 much at weddings.

Person above asking about 5D Mk1 focus assist - it does have them, only at apertures of 2.8 and wider.
 
Canon Bob said:
One thing to bear in mind with this discussion is that the 24-105 will not allow the 5D2, or any other body for that matter, to take advantage of the higher accurracy AF points. The lens needs to be f/2.8 or faster before the facility becomes available.
With an f/4 lens then the target focus will simply be within the depth of focus (not field) whilst an f/2.8 lens (or better) will be targetted to within 1/3rd of the depth of focus.

Bob
Click to expand...

Thanks for posting this, I've always wondered what exactly the high-precision focusing with 2.8+ was.

Maybe it's not such an issue with slower lenses anyway because there is more DoF anyway?
 
I dont know, so far the 5d Mk2 does't sound great unless your subjects are standing still, she wants it to photograph childeren and they don't stand still.
 
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