Canon 70-200 f/2.8L IS II not sharp at 200mm

[garymui]

I've been using my Canon 70-200 f/2.8L IS II for years now and it's always been my favorite lens for sports.  In my last couple outings, I noticed that I was getting a lot of blurry shots and I now realize that they are all my shots taken at full 200mm zoom.  Is it common to have focus go bad just at the long range of a lens?  Seems the same as usual at say 170mm and under.  Could something like this be fixed with AF Microadjustment?  In these cases, nothing is in focus (so it's not focusing on something else).  Do I need to take this in for servicing?

Thanks!

Gary

[Waddizzle]

Post some sample shots along with shooting data, camera and lens settings, and shooting conditions.  It is quite possible that you had a perfect storm of settings and conditions, and it was just coincidence that all of the bad shots were at the long end of the lens.

[garymui]

Thanks Waddizzle,

These were taken with a Canon 1DX, handheld with IS turned on using AI Servo Mode. RAW and converted with the same default Lightroom options. Looking at the Preview, I can't tell if the focus issue is very evident.  These were exported to a 5M limit to post here but I can otherwise upload full size images to my Flickr account and link them here.

Thanks!

Gary

At 200mm

At 120mm

At 70mm

Another at 200mm

And this one at 175mm

[ebiggs1]

" Do I need to take this in for servicing?"

First, thought is, no. Second, thought is, yes, because you will always wonder.  If any OOF shot you have you will always wonder if it is the lens.  Most of the time these situations are user error, not gear.

[garymui]

I don't think it's quite evident from these pictures posted here (limited to 5M and unable to really magnify).  I'll take some more test shots and post.  I've been taking these kind of photos for years with the same equipment and there has been some definite change in the last couple weeks shooting in the long end of the lens.  It's not an intermittent problem - it literally cannot take a single in-focus picture of anything at 200mm.

[ebiggs1]

To test, put it on tripod.  You can't do a test hand holding it.

[garymui]

Thanks! will do.

[Waddizzle]

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@garymui wrote:

I don't think it's quite evident from these pictures posted here (limited to 5M and unable to really magnify).  I'll take some more test shots and post.  I've been taking these kind of photos for years with the same equipment and there has been some definite change in the last couple weeks shooting in the long end of the lens.  It's not an intermittent problem - it literally cannot take a single in-focus picture of anything at 200mm.

---

There is an AF setting in your camera called Image Priority, which is designed for use with AI Servo mode.  Actually, there are two of them, 1st Image and 2nd Image Prirority.  Image Priority gives control over whether or not the camera will wait to lock focus before it fires the shutter, which it always does in One Shot mode.

You can adjust Image Priority for “Shutter Priority” or “Focus Priority”, or for some gray area in between.  Focus Priority means the camera will wait for an AF point to lock focus before firing the shutter.  Shutter Priority means the shutter will fire when you press the shutter, focus lock or not.  In most cameras, the default setting is the gray area between the two extremes.  

I set my cameras for “Focus Priority” for both 1st and 2nd Images when in Continuous Drive mode.  I see no reason to fire the shutter if the camera does not have a focus lock.  With fast focusing lenses, any drop in frame rate is negligible to non-existent.  I mostly shoot with an EF 100-400mm f/4.5-5.6L IS II USM and an EF 70-200mm f/2.8L IS II USM for sports.

If you like to “zone focus” before firing the shutter, then setting the 1st Image Priority to Shutter Priority would be the preferred setting.  The above shot was using IS Mode 1.  This next shot was taken using IS Mode 2.

There is more room for operator error than people realize.  On the first lap, I had used IS Mode 1, because I was shooting high jumpers and not panning at all.

Notice how soft this photo looks compared to the previous image.  I tried to catch them in the middle of the turn as they were more or less coming straight at me, but the shot is still a bit soft.

The moral of this story is simple.  The camera will do exactly what you ask it to do.  Make sure you ask the right questions.

[garymui]

Thanks for that info.  Haven't tried that but also haven't changed those settings so while I don't think it will resolve this issue, I will  use it going forward for my track photos!  And as a NY track parent, I always appreciate photos of Katelyn Touhy in action!  Once Flickr comes back up, here are my photos of the Girls Steeplechase race at Loucks - https://flic.kr/s/aHskRjCDUr

When I took the 200mm photos above, it was in AI Servo mode but I basically took it like a One shot photo.  Press, focus lock, focus indicators light up, and one press shot.  I'll take some more test shots both in AI Servo and One Shot and see if it makes any difference.

But thanks for your advice on this!

Gary

[ebiggs1]

" I'll take some more test shots both in AI Servo and One Shot ..."

I always tell new folks to master One Shot before you explore AI-servo. If you don't AI-servo can cause more problem than it helps. I really doubt any of the example shots displayed here required AI-servo.