topic Re: Is there a fix for 5d ii focus issue in EOS DSLR & Mirrorless Cameras

Is there a fix for 5d ii focus issue

khshultz — Sat, 22 Jun 2013 13:52:05 GMT

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.

Re: Is there a fix for 5d ii focus issue

TCampbell — Sat, 22 Jun 2013 16:04:53 GMT

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.

Re: Is there a fix for 5d ii focus issue

diverhank — Sat, 22 Jun 2013 16:34:29 GMT

Sharpness is so relative especially viewing at 100% and unadjusted RAW, especially for photos taken indoors in low light.

Try adjusting clarity, vibrancy and saturation a little bit before viewing...I often have the opposite problem with things being too sharp especially with the 24-70mm f/2.8L II when printed, say at 8x10 or less. But even for those (I think too sharp), they don't look that sharp at 100% so keep that in mind.

Since you tried it with multiple lenses...it is unlikely but there's a possibility of front or back focusing but it's worth a try. The 5D2 has microadjustments for lens and camera combination.

Re: Is there a fix for 5d ii focus issue

khshultz — Sat, 22 Jun 2013 17:13:40 GMT

Tim, Thank you for all the information and your time. I was aware of the camera showing the AF points in a photo and I checked those several shots the focal point was right on the eye of the person being photographed but the eye was still out of focus the shot was taken at f4.5, 1/200, ISO 200 at 70mm using my 24-70 and nothing even close to the eye is in focus. I have been shooting with a 50D for 3 years and never have had this trouble. I am confused as to why this is with this camera. I viewed the photos using Canon's DPP and same result the photos look very soft. I will check out the camera in Live mode. as you suggested. I did notice in one photo that I took the AF point was on the eye and just off to the right (compeletely off of the subject) there was a place in focus. Could that be what you are talking about where you need to adjust the accuracy of the lens? I have never heard of that before. I don't let the camera choose the focal point either, I pick the one I need for the shot. Thanks again for your help I really do appreciate it.

Re: Is there a fix for 5d ii focus issue

amfoto1 — Sun, 23 Jun 2013 15:03:16 GMT

There are no inherent "issues" with 5D or 5D Mark II focusing systems (the two models AF are essentially the same), per se.

It is an older, rather simplistic type of AF system.... perfectly adequate for many purposes... not so great for some others. For example, it's not ideal for sports/action photography, doesn't track moving subjects as well as some other Canon AF systems do. But it great for many things.... And actually someone practiced with it can even get sharp action shots, just will have a bit higher percentage of missed focus than with some other cameras. The 5D Mark III saw a much improved (and far more complex) AF system... and it's a much more expensive camera, too.

EDIT: Okay, I see now that you are coming from using a 50D, which in some ways has a more sophisticated AF system than the 5DII. The 5DII's AF has similar appearing 9 points showing in the viewfinder, but only the center one is the "better" and more sensitive dual-axis or "cross" type. In the 50D, all 9 points are dual-axis type and the center one is even further enhanced. So you should expect the 50D's peripheral AF points to be more responsive and accurate under a wider array of conditions. The 5DII is in some respects more similar to 30D or many of the Rebel series models AF system. Both models have a very similar AF Micro Adjust feature.

Now, the 5DII (and 5D classic) does have some AF features that the 50D doesn't. The 5DII has six invisible focus assist points, not shown in the viewfinder but clustered close around the center point. Two of those are dual-axis type. But, you have to enable "AF Point Expansion" in a Custom Function.... and, most importantly, this feature only works in AI Servo focusing mode. This does not work in One Shot. The expansion or assist points are illustrated on page 80 of the 5DII user manual and there is more information about setting it up on page 199.

If this is your first Canon (or maybe even if it's not), you might do well to view this half hour video posted on YouTube by B&H Photo... http://www.youtube.com/watch?v=iAx86nblZ2g It is the first of three in the series, a presentation by Rudy Winston of Canon USA, on how the Canon AF system(s) work and how to get the best out of them. Watch all three carefully and take notes. It's really an excellent orientation... covers several different models, but if memory serves, 5D Mark II is one of them.

Next, if you have "protection" filters on your lenses, remove them. Filters - especially lower priced, single coated or uncoated ones - can cause focus problems and/or overall image softness. (Just how much "protection" can a thin piece of glass be expected to provide, anyway?) Also, use a proper lens hood... it can help AF by keeping oblique light off the lens.

EDIT: Next, check to see if the previous owner of the camera might have Back Button Focusing set up on the camera. If you are using the normal or default method of focusing (with the shutter release button), but the camera has been set up to do BBF, you won't actually be focusing it at all. On 5DII, Custom Function IV, 1: Operation/Others, Shutter button/AF-On button is used to set up BBF (usually it's set to option "2. Metering start/Meter+AF Start"... but also Custom Function IV, 2: Operation/Others, AF-On/AE lock button switch might be enabled, swapping the function of the AF-On button and the * button). There is information about setting up BBF and AF-On/* button function swap on page 201 of the 5DII user manual.

Autofocus performance and accuracy relies upon three separate major "systems".... the camera, the lens and the user. You didn't mention what lens(es) you are using, but that can be a big factor too. For example, a non-USM lens such as the EF 50/1.8 is nowhere near as accurate focusing as a USM lens, such as the EF 50/1.4 or 50/1.2L. A very high resolution camera also will show up flaws in less than ideal lenses more than a low resolution camera, too. Today's full frame cameras sort of demand quality lenses. In other words, if you were using lenses on, say, an 8MP or 10MP crop sensor model before, and now are using the same on full frame, 21MP, any weaknesses of the lens are bound to show up a lot more obviously. Look for your lens' optimal aperture and focusing distances. Some lenses are fine wide open, but most benefit from stopping down a little.

Oh, and you have to watch out for too small apertures, too... there's an effect called "diffraction" that begins to occur on a 5DII at about f10 (assuming an 8x10 print) and increases with each smaller f-stop. Diffraction robs fine detail from an image. You likely won't notice it at all at f11, and there will be little at f16... but at 100% magnification you will start to see it at f22 and it will be pretty strong at f32 or smaller.

Watch slow shutter speeds on 5DII, too. If you are shooting in the range 1/30 to about 2 seconds, you might see "Mirror Shake" effect, where the bump of the mirror slapping up during exposure causes internal vibrations that can cause slight image blur (overall blurring, not parital as would be the case with missed focus). Use Live View or Mirror Lockup. It's also best to use a remote release or set the self timer, so you aren't touching the camera during exposure. Shorter and longer shutter speeds are less likely to show mirror shake effects.

The 5DII has Micro Adjust, that allows you to fine tune the focus of up to 20 specific lenses. This works best with primes, but can be applied to zooms, too. EDIT: You should check to see if the previous owner has dialed in any Micro Adjust for lenses. If he/she used a 24-70, for example, any adjustment made for that lens would also be applied to your 24-70, even though yours might not need the same adjustment. The camera does not recognize lenses by serial number, only by model. So, for example, if adjustment is made for an EF 50/1.4 lens, it will apply the same adjustment to any and all EF 50/1.4 lenses fitted to the camera. This is the case with the Micro Adjust on your 50D, too. (Some newer models with Micro Adjust, including the 5DIII, are serial number specific,and can be adjusted for more lenses: up to 40... and have a more sophisticated form of Micro Adjust for zooms.)

Yes, watch out for zooming in and looking at your images on your computer monitor at 100%. If coming from a much lower resolution camera, you might not realize how ridiculously large you are looking at the images from the 21MP camera. For example, the 30D is an 8MP camera and viewing it's images at 100% on most modern computer monitors is like looking at an approx. 3 foot wide print from that image. Using the same monitor and 100% now with a 21MP 5DII image is like making a five foot wide print and viewing it from 18" away... you are looking at the 5DII image much more critically. So, back off to 50% or so, for a more realistic evaluation of the image.

All images require sharpening, too. Digital cameras have an anti-alias filter in front of the sensor to try to prevent and effect called "moiré". This softens the image to a degree, but much of the crispness and fine detail comes back just fine once the image is sharpened. Your camera might have sharpening turned down or off... and you might want to leave it that way (it can be adjusted in the Picture Styles... and some styles apply more or less by default). It's okay to apply a little straight from the camera, but most sharpening should be done at the end of image editing and sizing, to maintain the best quality (how much sharpening is needed varies depending upon final size and resolution).

Finally, yes it is possible that a camera's AF system can get out of calibration. It might just need some fairly simple adjustment. I'd have a professional repair tech look at it, before returning a camera.

One way to tell is to compare the standard phase detection methods of focusing with the more accurate contrast detection method that's done in Live View. Set the camera to One Shot and use the AF points in the viewfinder normally to focus on a good, detailed subject, take a shot. Then switch to Live View and focus in that mode, take a shot. See if there is a difference. It's two entirely different focusing systems, so if there is a big difference between them under ideal conditions, the standard viewfinder based/phase detect system is likely out of adjustment. Live View focus is always the most accurate... but is also quite slow and not usable for many types of subjects. (P.S. you can use a similar method to set focus Micro Adjust, too.)

Hope this helps!

***********
Alan Myers
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses and accessories

Re: Is there a fix for 5d ii focus issue

khshultz — Sat, 22 Jun 2013 20:15:58 GMT

Thank you for all of the info. I tried the different Custom Functions you suggested. I am still having no luck. I have used a fellow photographers 5d iii and had no problems at all with theirs. I am really thinking something is wrong with this camera. I even tried setting all settings back to original settings. Nothingis remotely close to in focus, everything looks soft. I have tried different settings, fast shutter speeds, viewed at 50% on monitor (not a 100%), different lenses. I think the only thing I have tried yet is the auto adjustment for lenses but I would hate to think that I would have to adjust each lens to the camera for it to work. I can't even go out and take a snap shot of our dog with out her entire body looking soft and focused on her eye it looks soft too. I even tried putting the camera on auto still same results. I normally shoot in manual and in raw format. I read reviews stating that the 5d ii was so amazing and I find it hard to believe if everyone that bought the camera had the results I am getting today would feel the same, surely you do not have to and customize every setting in the camera to fit your lenses to get sharp focus?

I also took photos with it using manual focus and they are sharp as can be, same picture same settings switched back to auto focus and the result : very soft focus. I apologize if I am driving anybody reading this crazy, it definately is driving me crazy!!!!!!!!!!!

Re: Is there a fix for 5d ii focus issue

TCampbell — Sat, 22 Jun 2013 21:01:39 GMT

BEFORE we go too much farther, please go into your camera menu settings and check something:

Go to Camera Custom Function III (C.Fn III:Autofocus/Drive).

Check the value of setting #8 on that menu. It's called "AF Microadjustment". Make sure this is set to "Disable" (that's the factory default.)

It's possible someone set this to choice 1 which is "Adjust all by same amount" (and then there's a value that you can set). This would alter the AF on ALL lenses by the same amount.

The phase-detect AF sensors are basically on the floor of the mirror housing. The reflex mirror has a semi-silvered section which allows some light to pass through the mirror gets bounced DOWN to the AF sensors (while most light bounces UP into the viewfinder.) The sensor itself is, of course, at the back of the camera.

This means the focusing is not technically occuring on the sensor -- but separately. But the focus system and sensor should be calibrated to matched distances so that when the sensor believes it's focus, it actually does come to focus on the sensor.

If this your focus settings are zeroed and ALL of your lenses are missing focus then it's possible you need to have your camera adjusted. You'd want to send the body in to Canon for service (don't try to do this type of adjustment yourself.)

BTW - using the "live view" can help you confirm the issue since "live view" mode does not use the AF sensors on the floor of the body -- is a completely different focus system which analyzes contrast between adjacent pixels to determine if the camera is focused (focusing occurs directly on the sensor so there's no disconnect between a focus system that "thinks" it has good focus and an image that still comes out soft.)

Also, download and print a focus chart. You can print this on your own inkjet printer (you can buy commercially made targets as well.) It needs to be laid at a 45 degree angle. Put the camera on a tripod. Use a low f-stop to get a narrow depth of field. CAREFULLY make sure you focus only on the center line of the target (force the camera to use the center point) and take the shot. Deliberately run the focus on your lens all the way "in" and take a series of shots (forcing it to auto-focus each time). Then deliberately run the focus all the way "out" and take another series of shots (de-focusing each shot to force the camera to re-focus.)

You want to inspect the images to see if the camera is consistently missing focus and always in the same direction and by the same margin of error. Don't just take one image -- one image can always just be anomaly. Taking a series of images will help you identify if you've got a consistent trend going on.

Good luck!

Re: Is there a fix for 5d ii focus issue

khshultz — Sat, 22 Jun 2013 22:10:18 GMT

Thanks Tim, I checked the setting and it is on disable. I will perform the rest of the tests and get back to you. Thank you, I appreciate it!

Re: Is there a fix for 5d ii focus issue

khshultz — Sun, 23 Jun 2013 22:35:18 GMT

Well I tested it with the chart and pictures were still off, it looks like it focuses higher above the focal point each time. I talked to the person that I purchased it off and they said they will refund my money. Now my question would be....should I shell out the extra money for a new 5d ii or pay a even more for a 5d iii or do you think I would have better luck with another used one? I read so many good reviews on the 5D ii that I was hoping it would be an excellent camera but I don't want to have to go through this again. Any thoughts? Thank you to all of you helped me with this issue.

Re: Is there a fix for 5d ii focus issue

TCampbell — Mon, 24 Jun 2013 02:21:50 GMT

This depends on what type of shooting you normally do.

The 5D II is a very good camera. It was extremely popular among wedding and portrait photographers (not so popular among sports photographers). Focus issues like the one you've just experienced aren't typical. I still have my 5D II and while it's focus system can't compete with the 5D III, it's still a great camera.

The focus system on the 5D III is amazing... but if you're not shooting at speed under pressure and have time to focus (e.g. think "landscape" or "portraits") then the 5D II focus system is completely adequate.

The 5D II has the 9 AF points you've seen on the body you purchased -- only the center point is "cross type". It has some hidden "focus assist" points which aren't etched on the focus screen to help focus in the center area (and you can turn those off -- sometimes enlarged focus areas can be a problem when there's a very specific but tiny point where you want to lock focus.)

The 6D system is better than the 5D II (not nearly as good as the 5D III) but at a considerably reduced price tag.

If you're not shooting at speed, under-pressure, and would rather save a few dollars on the body and have more to put toward nice lenses, I'd probably still go for a 5D II... or maybe a 6D. If you need a camera with outstanding performance, then the 5D III is your baby... just not cheap.

Re: Is there a fix for 5d ii focus issue

khshultz — Mon, 08 Jul 2013 02:17:57 GMT

Hello,

I wanted to let everyone know that I returned the 5Dii and they refunded my money. I decided to go with the new Canon 6D and I have to say that I am VERY impressed!! The shutter speed is so quiet and the sharpness, clarity is beautiful in normal light and low light. I cannot believe how good it is in low light, which is what I was looking for. The auto focus is very fast and efficient too! I also keep asking myself "why did I not go full frame sooner" 🙂 I love the camera!!!!! Thanks for all of your help!

Re: Is there a fix for 5d ii focus issue

kotaiba — Thu, 09 Jan 2014 13:02:29 GMT

this is specifically my problem as well. focus on one thing using a single focal point..shoot and bamm the focal point is highlighted someother place!!

Re: Is there a fix for 5d ii focus issue

diverhank — Thu, 09 Jan 2014 17:00:59 GMT

@kotaiba wrote:
this is specifically my problem as well. focus on one thing using a single focal point..shoot and bamm the focal point is highlighted someother place!!

Kotaiba,

There is a possibility that this is a technique problem, rather than camera problem, especially for those who focus then recompose (pointing elsewhere). The default setting is that whenever you press the shutter button half way, the camera will re-focus (on the wrong point if you recompose). So once you achieved focus, you must either keep the shutter depressed half-way until shutter release or you press the AF-lock button (you need to customize this).

I disable the camera focus in the shutter button (customization) and use only the back focus button to focus to avoid this problem.

Re: Is there a fix for 5d ii focus issue

millerker — Mon, 06 Apr 2015 06:32:02 GMT

I've come to this thread very late but just wanted to say that I have had focusing issues ever since I bought my canon 5D Mark II. I have never felt that it focuses well and I'm never happy with the images. I was told when studying photography at RMIT in Melbourne Australia by one of my lectureres that a very high percentage of digital cameras come off the shelf with focusing problems. I was also recently told by a staff member at Camera Warehouse, a retail digital camera chain, that Canon 5D Mark II's are renowned for not taking sharp images. Up until this point I had always blamed my technique. I'm going to try these things on this thread to see if I can work out if in fact it is my camera or my technique.

Re: Is there a fix for 5d ii focus issue

RobertTheFat — Mon, 06 Apr 2015 11:39:44 GMT

@millerker wrote:
I've come to this thread very late but just wanted to say that I have had focusing issues ever since I bought my canon 5D Mark II. I have never felt that it focuses well and I'm never happy with the images. I was told when studying photography at RMIT in Melbourne Australia by one of my lectureres that a very high percentage of digital cameras come off the shelf with focusing problems. I was also recently told by a staff member at Camera Warehouse, a retail digital camera chain, that Canon 5D Mark II's are renowned for not taking sharp images. Up until this point I had always blamed my technique. I'm going to try these things on this thread to see if I can work out if in fact it is my camera or my technique.

Regardless of what your camera store told you, I've never heard anyone suggest that the 5D2, or any other member of the 5D series, was chronically prone to sharpness problems. Unless you're ready to give up and trade your camera in on a 5D3, you're right to try to track the problem down. If you haven't done so already (and maybe even if you have), I'd suggest carefully checking the autofocus microadjustment settings. Inaccurate AFMA isn't necessarily the most likely source of the problem, but it's probably the easiest to fix or rule out. And it doesn't require sending the camera in for service. So it's the obvious place to start.

Re: Is there a fix for 5d ii focus issue

TTMartin — Mon, 06 Apr 2015 16:41:40 GMT

@millerker wrote:
I've come to this thread very late but just wanted to say that I have had focusing issues ever since I bought my canon 5D Mark II. I have never felt that it focuses well and I'm never happy with the images. I was told when studying photography at RMIT in Melbourne Australia by one of my lectureres that a very high percentage of digital cameras come off the shelf with focusing problems. I was also recently told by a staff member at Camera Warehouse, a retail digital camera chain, that Canon 5D Mark II's are renowned for not taking sharp images. Up until this point I had always blamed my technique. I'm going to try these things on this thread to see if I can work out if in fact it is my camera or my technique.

All cameras and lenses (not just Canon or the 5D Mk II) have manufacturing tolerances. The small error caused by these manufacturing tolerances can add together and become noticeable, or they can cancel each other out and make the camera spot on.

For more informaton read: "This lens is soft" and other myths, by Roger Cicala @ lensrentals.com

The Canon 5D Mk II has micro focus adjustment which allows you to compensate for manufacturing tolerances. Micro focus adjustment should be done at the distance and type of light you normally shoot / use your camera. Newer cameras allow you to micro focus adjust a zoom lens at both ends of zoom range. The 5D Mk II only allows one adjustment per lens, typically this should be done at the long end of the zoom range as this has the shallowest depth of field. One of the best methods I've found for micro focus adjustment is DotTune: Autofocus fine tuning in under 5 minutes.

Most AF issues people have are not related to the camera, but, instead are caused by misunderstanding the AF system. Auto focus isn't as automatic as most people assume. A few years back Canon did an hour and half class on auto focus at B&H.

A Look at The Canon Autofocus System Part 1

A Look at The Canon Autofocus System Part 2

A Look at The Canon Autofocus System Part 3

Watching these video recordings of the presentation will substantially improve your understanding of auto focus, and results using it.

Re: Is there a fix for 5d ii focus issue

a747bldr — Fri, 08 May 2015 04:28:50 GMT

I have the same problem with my used 5D MKII.....

I thought I was doing something wrong, but now I see that it is the Camera....!

I have much better luck in obtaining clear shots by focusing manually, which is a pain...

This situation is unacceptable (my Nikon D5100 was always in perfect focus)

Time to sell the 5D.

Re: Is there a fix for 5d ii focus issue

TCampbell — Fri, 08 May 2015 05:48:10 GMT

My 5D II and 5D III are fantastic.

You might want to read this article: http://www.lensrentals.com/blog/2008/12/this-lens-is-soft-and-other-myths

The 5D II supports auto-focus micro-adjustment... meaning you can test and fine-tune the focus accuracy on the camera -- which can be different for EACH lens you own.

When I test the camera using a focus-test chart it's bang-on accurate every time and with every lens I test. This is not to say that it will always be accurate with every lens. Every so often a single "copy" of a lens will be flawed. But the higher end the lens, the less likely that you'll encountered a flawed copy.

Here's the thing: DO NOT take ordinary pictures and use that as a test of camera focus accuracy. There are simply far too many reasons why a perfect camera & lens combination can end up with a soft image that having nothing to do with the camera.

If you want to test a camera, you have to isolate all those other causes. The camera has to be tested with camera on a tripod, using a stationary focus test chart (and there are parameters for how these have to be setup to have a valid test -- chart instructions usually explain how to establish a proper test distance which will vary based on the focal length of the lens). The conditions need to be controlled. If the camera & lens are soft under "controlled" conditions, then you (a) might have an issue and (b) you can usually isolate the specific cause to where you will know what needs to be addressed to correct the problem (and often it's something you can do yourself.)

There is nothing plaguing the 5D II.

There were huge complaints about the 5D II focus system... but the complaints were not about accuracy problems, they were largely about how a $2500 camera body ends up with the same basic focus system that they had on a $500 camera. When Canon released the 5D III they went all out on the focus system. The 5D III had one of the very best focus systems of any camera on the market when it was released (only the 1D X was better... and that system was only very fractionally better.)

There is a "story" behind how the 5D II ended up with that same basic focus system. I'd rather not share the story here because I have no way of knowing if it's true.

If you allow the camera to auto-select the AF point, then it is programmed to always select the point at which it can achieve a focus lock at the CLOSEST focusing distance to the camera. If you don't want it to do that, then tell it to pick a specific point (poke the AF point selection button, then use either the selection wheel on the front OR the navigator joystick on the back to select the AF point you want.)

If everything is used correctly and you STILL have a focus problem, you need to properly test the lens with a focus test chart and perform the auto-focus micro-adjustment. If you STILL have focus problems even after performing that (in properly controlled test conditions) then the culprit is likely the lens.

The reason it can be the lens has to do with "how" the phase-detect AF system works. It's possible to derive the correct focus position from merely one sample off the AF sensor. Due to the nature of "phase detection" the camera can determine if the focus is either in-phase vs. out-of-phase; if out-of-phase the camera knows which direction it needs to go (it knows if focus is too far vs. too close); and it actually knows precisely how far it needs to adjust. When the computer samples the focus point, it orders the lens to adjust by a specific amount which should send the lens to perfect focus every time. But if that lens has gear backlash then the lens can miss focus due to backlash issues -- that's a lens problem -- not a camera body problem.

Another way to test for issues with the phase-detect focus system is to switch to "live view" and test focus that way. Live view mode uses "contrast detect" auto-focus instead of "phase detect" auto-focus. Contrast detect is slower and requires that the camera iterate through numerous focus checks before it can be sure it's properly worked out focus... but due to the way it works, the camera cannot just "know" which way it needs to adjust -- nor how much of an adjustment is needed. So it has to keep re-sampling the image. This makes for a much slower system... but because it keeps refining and re-evaluating the focus, it tends to always nail the focus (eventually). Phase-detect will nail the focus much faster (it's near-instantaneous) IF everything is working correctly.

Re: Is there a fix for 5d ii focus issue

shuttergal1 — Tue, 26 Jan 2016 14:44:11 GMT

Take off the lens and check the focal glass inside the body of the camera. I've had the same issue as you, and both times, it was due to the focal glass falling out of the camera body. (They'll be a rectangular piece of plastic that's just laying in the body after removing the lens--you can't miss it!) First time, I had it sent to Canon for a full repair. Now here I am with the same issue, and I'm attempting to fix it myself!

Re: Is there a fix for 5d ii focus issue

kathurima — Wed, 07 Sep 2016 02:54:10 GMT

I'm extremely late to this party but I too must admit I am having the same issue with my 5D Mark II. I have since acquired a couple of other bodies (7D and 60D) and neither has that issue. The 60D in particular is tack sharp. Same settings, same lenses. And yes I have disabled AF micro-adjust. I rented 5D3s for some recent shoots (different bodies from different renters) and was blown away by their focus accuracy (again same settings, etc.) I was strongly considering a 5D3 as my upgrade path....that was until the 5D4 was announced. I typically will skip a generation before considering an uppgrade, so this is really perfect timing. If the 5D3s I rented are anything to go by, the 5D4 will be an absolute focus magnet. I have been really frustrated with my 5D2 and can no longer trust it to deliver the results I seek.

5D4 here I come!