Canon 70-200 f4L IS unusable at f4

Hi all,

I went out and shot some foto's of planes at the airport of Amsterdam this afternoon. First I shot wide open with my 70-200 f4L IS on a 5D mark III, but after looking at the images on the back of the screen I noticed they weren't really sharp. So I decided I'd bump the aperture up to f8, and was happy with the results there. Once back home, I reviewed the images in Lightroom and ended up trowing away all of the images take at f4... Below are a few of them, straight out of camera, with standard Lightroom profile and 25 sharpening.

I did apply AFMA to this lens so that is not the issue... I have been noticing the lack of sharpness at f4 earlier already, and it makes me want to sell it to buy the 70-200 f2.8L IS II. I also thought this f4 lens was considered to be tack sharp even wide open! BTW I also have a 16-35 f4L IS and that lens is stunning at f4 across the whole frame. I would like to hear your thoughts about this.

Marc

The last one is one shot at f8

J A C S wrote:

Marc dbr wrote:

I did apply AFMA to this lens so that is not the issue...

Actually, this can very well be the issue. Use LV.

I have this lens and have used it a lot on 7D and 7D2s and your shots, even at f8 don't  look as sharp as I remember.  I recently got a 5D4 but haven't tried that lens on it yet.  I'll see if I can shoot some thing at a similar distance with grass and see how sharp it comes out with the 5D4.

my thought exactly

whether its focus issue, or a bad copy issue, I dont know. here is full size image, 5d3. you can click for the full size 100% detail.  this is at f4.

the lens is sharp wide open. get it checked out.

I am pretty sure mine can not be physically stopped down past wide open: not sure if it ever has been.  Lol. No problems at f4 here.

...before the arrival of the Canon 70-200LII, was called the best telephoto zoom lens ever.

I own this lens and it's very sharp at F/4. I had to apply a bit of AFMA to really dial in the sharpness but it wasn't far off at all right out of the box.

It's possible that yours has some kind of issue or that the AFMA that you applied is contributing to the softness. Below is an example of how sharp this lens is wide open at f/4 (minimal sharpening applied). If anything, I need to soften it up to show less detail for this type of shot.

70-200 f/4 IS: @ f/4 200mm

I believe this is a known issue with some copies of this lens. My first copy, at least, had similar problems at F/4 - I could see a very significant improvement stopping it down to F/5.6. The discrepancy seemed to be most pronounced at infinity/relatively long distances. I spent a long time making sure that it was not a AFMA issue and also checking online reviews that showed the difference in sharpness at different apertures and focal lengths. As soon as I tested out a different version of the lens, however, I knew immediately that mine was not functioning as it should. Really, the difference in sharpness between F/4, F/5.6 and F/8 is very negligible. I honestly doubt I would be able to tell the difference, even looking at 100% view, in many instances. So I sold my first copy (with full disclosure) and bought another copy that is extremely sharp at F/4 at all focal lengths. Autofocus is really reliable too. This lens really is as good as everyone says. And I love how lightweight it is considering the quality it produces. Works great with the 1.4 extender too. I would never consider buying the F/2.8 version unless perhaps if I was to become a pro wedding/event photographer.

Best of luck!

Shane

Marc dbr wrote:

Hi all,

I went out and shot some foto's of planes at the airport of Amsterdam this afternoon. First I shot wide open with my 70-200 f4L IS on a 5D mark III, but after looking at the images on the back of the screen I noticed they weren't really sharp. So I decided I'd bump the aperture up to f8, and was happy with the results there. Once back home, I reviewed the images in Lightroom and ended up trowing away all of the images take at f4... Below are a few of them, straight out of camera, with standard Lightroom profile and 25 sharpening.

I did apply AFMA to this lens so that is not the issue... I have been noticing the lack of sharpness at f4 earlier already, and it makes me want to sell it to buy the 70-200 f2.8L IS II. I also thought this f4 lens was considered to be tack sharp even wide open! BTW I also have a 16-35 f4L IS and that lens is stunning at f4 across the whole frame. I would like to hear your thoughts about this.

Marc

The last one is one shot at f8

Marc.

I carried  my 70-200 f/4 L IS along with my 16-35 f/4 L IS and 24-70 f/4 L IS last month to Amsterdam. Looking back at images I see consistency through out all three lenses.

Having never MFA any of my lenses, mostly because I would be so anal about it, I can't really comment on that. You may want to consider sending it in to Canon to at least have it looked at.

Funny you mentioned the 70-200 f/2.8 L IS Mark II. I have been leaving it at home as I have been traveling quite a bit to Europe lately and more so in the future. Since my 16-35 f/4 L IS and 24-70 f/4 L IS were f/4, do I really need f/2.8 in the 70-200 range? Will I see dramatic loss of image quality? I now only bring the f/2.8 L IS Mark II on location when I absolutely need it, like weddings for example.

And the weight difference is drastic.

I let  the job determine which 70-200 to bring. Sometimes my back and shoulder tell me also.

sobrien wrote:

I believe this is a known issue with some copies of this lens. My first copy, at least, had similar problems at F/4 - I could see a very significant improvement stopping it down to F/5.6. The discrepancy seemed to be most pronounced at infinity/relatively long distances. I spent a long time making sure that it was not a AFMA issue and also checking online reviews that showed the difference in sharpness at different apertures and focal lengths. As soon as I tested out a different version of the lens, however, I knew immediately that mine was not functioning as it should. Really, the difference in sharpness between F/4, F/5.6 and F/8 is very negligible. I honestly doubt I would be able to tell the difference, even looking at 100% view, in many instances. So I sold my first copy (with full disclosure) and bought another copy that is extremely sharp at F/4 at all focal lengths. Autofocus is really reliable too. This lens really is as good as everyone says. And I love how lightweight it is considering the quality it produces. Works great with the 1.4 extender too. I would never consider buying the F/2.8 version unless perhaps if I was to become a pro wedding/event photographer.

Best of luck!

Shane

I should add that my first copy was a good few years old. My existing copy is only a couple of years old. So it could be that it is an issue that (i) is more prevalent in older models for production reasons etc. or (ii) happens over time. I am hoping that it is (i) as the prospect of my new lens losing its edge over time would be disappointing. Time will tell I suppose.

Unfortunately I do not know enough about the issue to know if it is repairable or what that would cost.

Because Polderbaan?

Yes Polderbaan! but that doesn't explain why f4 images aren't sharp 😄

Marc dbr wrote:

Yes Polderbaan! but that doesn't explain why f4 images aren't sharp 😄

I was thinking maybe some North Sea haze.

Well everything you describe is the exact same behavior of my lens! I have been noticing this during the couple years I have this lens, and it has been bothering me quite a bit, I thought it had to do with the far distance. My other L lenses do not show any signs of softness when shooting from a distance, so I figured I would sell it too.

Maybe I might buy a new copy of this lens, but at this point I am leaning towards lenses   such as the 100-400 version ii or the 70-200 f2.8 ii because of the longer reach and the bigger aperture. Though when it is sharp (i.e. at close distances) I love my 70-200 f4 is!