Canon EF 24-70 F2.8 mk11 focusing issues

[Dash]

Hi, I covered a wedding yesterday. Used a 5Dmk111 and a Canon EF 24-70 F2.8 mk11. A lot of my shots were at 24-30mm @ f2.8 or f3.2 and a large proportion of these were out of focus. The chosen focus point was in centre but the focus in the shots was at extreme left or right! I used the same camera body with a 70-200 F2.8 L without trouble.

The 24-70 lens is only 10 months old.

Been shooting for the last 30 years, so can confidently say "human error" is unlikely.

Has anyone else had this problem?

[ebiggs1]

"Been shooting for the last 30 years, so can confidently say "human error" is unlikely."

I am going out on a limb and guess "human error" is the cause.  Of course there is always the posibility of equipment failure.

Barring that, however, you know very well (30 years worth) f2.8 is going to have shallow DOF and a slight miss focus point is going to result in what you are seeing in your photos.

On weddings I use center point only.  Focus carefully and deliberately.  Make sure your camera is not cocked slightly or angled toward the subject.

And, I always use two or more cameras!

[TCampbell]

Lots of questions spring to mind... primarily I'm wondering what AF point selection mode you were using since the 5D III is quite a bit more sophisticated than most other bodies and it is not at all unusual to find 5D III owners who aren't familiar with how they all work and why a person would select one over another.

Canon has a great article covering the focus system here: http://www.learn.usa.canon.com/resources/articles/2012/1dx_guidebook.shtml (look near the lower left corner of that page and you'll find a link to download their PDF guide on the focus system.) They also have a number of instructional videos that they've recorded and posted to YouTube. You can search for info on the 1D X focus system as well as 5D III since both camera have the same options for AF point selection modes and tracking. They effectively have the same focus system (although there's one slightly nuance which Canon explains on that web page I linked above.)

Shooting everything mostly at f/2.8 is also not without it's own hazards. Subjects all need to be at the same focus distance rather than composed diagonally, etc. to keep everyone in the acceptable focus range.

[limvo05]

I am no expert in this arena, however, I do have the same lens and noticed a slight back focus with my 5Ds. After making a slight micro adjustment, the issue is resolved and I don't use any filter with it other than Lee's ND filters. That said, I don't do portrait or wedding, as said earlier, I am still learning how to take photos.

Cheers,

LV

[sandyn]

I had a similar problem with my 24-70 f2.8. It turned out to be the UV filter. For some very strange reason the particular type of filter caused incorrect focussing (was in inexpensive filter). If I tried the same filter on my 200mm f2.8 it worked fine. Replacing with a Hoya cured the problem.

[Waddizzle]

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@sandyn wrote:

I had a similar problem with my 24-70 f2.8. It turned out to be the UV filter. For some very strange reason the particular type of filter caused incorrect focussing (was in inexpensive filter). If I tried the same filter on my 200mm f2.8 it worked fine. Replacing with a Hoya cured the problem.

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I am not surprised by that news.  I noticed the same issue with the EF 100-400mm f/4.5-5.6L IS II USM, and the EF 70-200mm f/2.8L IS II lenses.  My photos were softer when I used any kind of filter, except for a Clear protective filter, especially the 100-400.

[ebiggs1]

The Hoya is an Ok filter.  The B+W 72mm XS-Pro Clear MRC-Nano 007 Filter is a great protecto filter.  Don't forget the most important fact, filters remove just as easily as they went on.  When in a situation where the filter may impact, very rare, the shot, take it off.

[Sksherwani]

Hey Dash this happens to me sometime if I shoot on HSS, to prevent this stop using HSS then you will get sharp images on this same focal length and F-stop.

[Sksherwani]

Hey sandyn can you please tell me which lens version you have 24-70mm 2.8 IS or IS ll??

[sandyn]

It is the 24-70 2.8 MkII (I wish there was a IS version of the f2.8!:-) )