Is there a fix for 5d ii focus issue

Question

Hello,  I just purchased the 5Dii used but the owner said the camera was working perfectly. I notice that when I take photos the photos do not look sharp. I am shooting in raw and using fast enough settings that they should be sharp. I tried different lenses and a tripod still same results when viewed at 100%. So I have been reading about the 5d ii having focus issues and was wondering if there is a fix to this problem? Also, I read that with 21 mp the photos won't look sharp in the view finder or when viewed at 100% has anyone else heard this?  Any suggestions would be helpful. I am thinking I need to return the item which is a shame, I was so excited to get the 5d ii and very disappointed to be having this issue.  

Answer 1

I don't suggest using the viewfinder to judge quality of photos -- it's too small.  
There are no focus "issues" with a 5D II -- it's an excellent camera.  It doesn't have the advanced focus system of the 5D III but if the focus points on your 5D II tell you that something is correctly focused then it should be correctly focused.
There are NUMEROUS things that can cause problems (none of which are defects.)
1)  If you allow the camera to auto-select it's focus point, remember that the camera will always pick the focus point which can lock focus at the closest focusing distance.  Suppose you're taking a photo of someone's face, but on the side of the frame there's a bush -- and that push is in far enough that one of the focus points is on the bush.  The camera will focus on the bush and NOT on your subject's face.  Usually you will want the camera to focus on the nearest subject, but when shooting shots with distracting elements in the frame which are closer then your intended subject, you need to pick the focus point you want the camera to use rather than allow it to auto-select the point.
2)  If focusing at a particularly low focal ratio (especially at close distances) the depth of field can get REALLY thin.  If you want focus on your subject's eyes -- you will need to carefully position the focus point and lock focus on your subject's eyes -- otherwise you may end up getting a focus lock on their nose (as an example) and the eyes will be slightly soft.
3)  In the default "one shot" mode, the camera will focus prior to taking the shot.  When focus lock is achieved the camera will stop adjusting focus.  If either you or your subject move after that point, the camera will NOT re-adjust -- you'll get  a soft shot.  With moderate f-stops usually a small movement wont change focus distance enough to matter -- this is mostly an issue at shallow f-stops.  But if shooting action where you KNOW your subject is moving and focus distance is changing, you need to use the "AI Servo" mode which continuosly updates focus.
4)  Your 5D II allows you to adjust the focus accuracy of a lens.  Some lenses will routinely focus just slightly in front or behind your intended focus distance.  When you detect that you have a lens that does this, the camera can compensate.  This adjustment requires that you set up an accurate focus test to determine if an adjustment is needed and how much.  Do not attempt to make an adjustment by using regular every-day shots... use a carefully controlled focus target, tripod, etc.  There's a procedure for doing this.
5)  If you suspect inaccuracy with focus points (and you really need to be careful to use controlled circumstances before arriving at such a conclusion) you can test by switching to "live view" mode to see if you get different results.  Live view mode does not use the phase-detect auto-focus points... it uses contrast-detection focus instead.  Contrast detection is slower but in theory should be able to provide more accurate focus as long as you have a subject with some decent contrast.  If live view is consistently outperforming the standard phase-detect AF mode then you may need to perform focus adjustment on your camera (this is specific to each lens you own... this is because each lens can behave differently.)
Lastly... your camera records which AF points were used when it takes a photo.  This data can be displayed IF you use the Canon EOS Utility (which should have come with your camera).  It'll put the familiar focus array overlaying your photo and highlight the active point(s).  Just be aware that if you did a "focus and recompose" that the camera is going to report which focus point was used to lock focus but wouldn't know you recomposed the shot.  If you're not recomposing and your subject distance wasn't changing then the utility should be accurate.
Incidentally, Apple's "Aperture" software also allows you to view the Canon focus point data.  As far as I'm aware, this is not available in Lightroom or Photoshop.
Tim Campbell
5D II, 5D III, 60Da