My Canon EF 70-200mm f/2.8 L IS II Soft at 2.8? Help!

[Elon Gane]

A few days ago I got theCanon EF 70-200mm f/2.8 L IS II. [:D]


I have been very pleased with it...But I have just today noticed at 200mm in the corners at f2.8 are somewhat soft. Stopping down to f5.6 seems to help some.


In the center it is not a problem, it is just in the corners.


Here are some crops from corners. I took them with my Canon Rebel XSi. Imanually focused them in the live view.





at f2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/IMG_5F00_9668.JPG


And at f5.6


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/IMG_5F00_9667.JPG


Is it normal for theCanon 70-200mm f/2.8 L IS II to be soft in the corners at f2.8?


Here are a couple more crops.


At f2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/IMG_5F00_9702.JPG


And at f5.6/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/IMG_5F00_9701.JPG


Should I return my copy for a new one or not?


What to you think?


Thanks for any help!

[realityinabox]

Dang, if that is what you call soft, I'd dare you to look at my old sigma 28-70, even stopped down.


I don't think it is unreasonable for a zoom lens to be slightly soft in the corners when wide open at the long end.


You said you did a live view manual focus, where did you focus at? the center, or right on that spot? 2.8 at 200mm would make for a thin DOF, so if you're focusing on the center of the frame, the corners might not be on the same plain of focus. Just a thought.

[Daniel Browning]

I don't think it should be that soft. I suggest returning it. EDIT: realityinabox makes an excellent point: you can't evaluate corner sharpness if you didn't use the liveview 10X on the corner that you're examining.

[Jon Ruyle]

Daniel and realityinbox are right: before you return the lens, make sure you focused properly. It's not easy. I usually take 10 pictures and keep the sharpest. I use liveview at 10x exactly at the part of the picture I'm evaluating. (If you focus the center, the edges will be out of focus because the camera is probably not square to your target).


Even the 70-200 II is not perfectly sharp in the corners. Here is a crop from the lower right corner of mine at 200mm f/2.8 taken with my 5DII:


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.25.93/Mk-2-lr.jpg


It's a little tough to compare to the xsi because on one hand, unlike the pic from your rebel, it really is in the far corner of the 35mm frame. On the other hand, the pixel density on the 5DII isn't as high as that of the rebel, so your pic reveals more softness.


Another thing to keep in mind: not all corners are created equal. My 70-200 has one corner (upper left) which is softer than the other three:


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.25.93/Mk-2-ul.jpg


I actually considered returning mine, but in the end decided against it: the "bad" corner is still better than my Mk1's best corner, and if I returned my lens, maybe I'd get one with 2 bad corners. I just have no idea how common that is.


By the way, many people report that the 70-200 II is as sharp as primes such as the 135mm f/2. Mine isn't quite as sharp as my 135 f/2 @ f/2.8, but the good corner is close. Here is crop from the corner of my 135 f/2 taken @ f/2.8:


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.25.93/135-lr.jpg


I won't tell you if you should return your lens, but I hope some of this info is helpful.

[Elon Gane]

Thanks Guys!


I used the 10x live view to focus in the same corner as those crops. I also used a tripod.

[neuroanatomist]

Thanks Guys!


I used the 10x live view to focus in the same corner as those crops. I also used a tripod.






I will say that Jon's images, which are from a FF camera, may not be directly relevant to you since the corner of his image is actually cropped away on your 1.6x FOVCF body. I'll try to shoot something with my 70-200 II on my 7D for comparison, but given what you've done so far,I'd return the lens (or send it to Canon for adjustment).

[Jon Ruyle]

I will say that Jon's images, which are from a FF camera, may not be directly relevant to you since the corner of his image is actually cropped away on your 1.6x FOVCF body.


Agreed- they're not directly comparable. On the other hand, if Elon judges the 1.6 FOVCF corner images much softer than my FF corner images (taking differing pixel densities into account), then something probably is wrong.

[neuroanatomist]

If you look at Bryan's LIS II. Camera-to-subject distance was about 10 feet -DoF at 200mm, f/2.8 is less than 2 inches,so I chose a flat subject (the back of Michael Freeman's Perfect Exposure). Shots were tripod-mounted and lit with an off-camera Speedlite 430EX II placed at a 45° angle about 3 feet from the book and wirelessly triggered with the 7D's built-in flash.


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.35.15/70_2D00_200II-corners.jpg


As you can see, the f/2.8 image is a little less sharp and has a little less contrast. As Jon stated and Bryan's ISO 12233 crops show, a little corner softness wide open is normal for this lens (almost all lenses, in fact). The MTF/resolution tests at photozone.de (http://www.The-Digital-Picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687&Camera=453&Sample=0&FLI=3&API= 0&LensComp=687&CameraComp=453&SampleComp=0&FLIComp =3&APIComp=3]ISO 12233 crops for 200mm f/2.8 vs. f/5.6, you can see that at mid-frame and in the corner, the lens is a little bit sharper at f/5.6 than wide open.



I'll try to shoot something with my 70-200 II on my 7D for comparison


Here are 100% crops from the extreme corner of a pair of shots taken with my 7D andEF 70-200mm f/2.8<span style="color: red;) also show slightly lower resolution at f/2.8 (not just in the corners) with this lens on a 50D.


I should also point out that for the above test I disabled peripheral illumination correction in DPP, and had to bump up the exposure on the f/2.8 image by half a stop to compensate for the small amount of optical vignetting this lens has wide open (even on a crop body). I compared with vs. without PIC, and the correction actually seems to soften the corners by a tiny (very tiny) amount and reduce the contrast as it increases the brightness to compensate for vignetting.


Obviously, since we're all shooting different scenes it's tough to tell for sure, but it looks (to me) like your images have a greater differential between f/2.8 and f/5.6 than mine (or Jon's before they disappeared).

[Elon Gane]

Thanks everybody!


Right now I'm leaning<span>against returning it because I will need this lens for the next two weekends and again two weeks after that. (I think it would probably take a fair amount of time to return and then get a new copy right?) By that time it will be to late to return in to Amazon. But I could send it to Canonfor adjustmentright? Would the warranty cover the costs?


Anyway here are some more crops. I took them at 200mm with580EX II Speedlite bounced and with a tripod.


Center at F2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/CenterF2.8.JPG


Center at F5.6


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/CenterF5.6.JPG


Top left corner at F2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F2.8TopLeft.JPG


Top left corner at F5.6


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F5.6TopLeft.JPG


Top right corner at F2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F2.8TopRight.JPG


Top right corner at F5.6


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F5.6TopRight.JPG


Bottom right corner at F2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F2.8BottomRight.JPG


Bottom right corner at F5.6


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F5.6BottomRight.JPG


Bottom left corner at F2.8


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/f2.8-BottomLeft.JPG


Bottom left at F5.6


/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.46.81/F5.6Bottom-Left.JPG


So if you guys don't think it looks to bad I guess I will keep it for now.

[Jon Ruyle]

It would be a shame if you want to return the lens but are keeping it for just a few weeks of use. (Not saying you *should* return it, but if you want to, you should be able to).


Amazon is very good about returns/exchanges. They might ship you a new one as soon as they get the old one, and you could probably have the new lens shipped next-day.


You might even consider, instead of an exchange, buying another and returning the old one as a separate transaction.

[Elon Gane]

Thanks Jon! I think you are right.


I think I should return it now, I was just testing myCanon EF 70-200mm f/2.8 L IS II with my oldCanon EF-S 55-250mm f/4-5.6 IS and the 55-250($230) Was slighty sharper at f5.6 in the corners, then my 70-200($2300) at f2.8.


I do not think it should be that way, should it? A $230 lens beating a $2300 lens for corner sharpness? Looking at the#mce_temp_url# ("http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687&amp;Camera=453&amp;Sample=0&amp;FLIComp=4&amp; APIComp=1&amp;LensComp=456&amp;CameraComp=452&amp;SampleComp=0 &amp;FLI=3&amp;API=0)seems to say this as well.

[Jon Ruyle]

I do not think it should be that way, should it? A $230 lens beating a $2300 lens for corner sharpness? Looking at the#mce_temp_url# ("http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=687&amp;Camera=453&amp;Sample=0&amp;FLIComp=4&amp; APIComp=1&amp;LensComp=456&amp;CameraComp=452&amp;SampleComp=0 &amp;FLI=3&amp;API=0)seems to say this as well.


I agree, it should not. I've never owned a zoom as sharp @ f/2.8 as my 70-200, and I would expect it to be sharper than the 55-200. Bryan's crops seem to bear that out (though you have to be careful comparing a crop with a 40D to one with a 5DII because they have different pixel densities and different corners).


I wasn't sure if I should mention this, because I don't have hard data to back it up, but it is my impression that my 70-200 is very sharp in the 1.6fovcf area (away from the extreme full frame corners). With a 2x extender it absolutely kills the Mk 1.


If you can arrange it so Amazon sends you a new lens in time, I say go for it.

[Daniel Browning]

I do not think it should be that way, should it? A $230 lens beating a $2300 lens for corner sharpness?


Usually, no, it's shouldn't be that way. Especially not in your case. But sometimes it is normal and expected. For example, the $100 50mm f/1.8 beats the $1500 f/1.2 in corner sharpness at *every* f-number:


50mm f/1.8 at f/1.8 vs 50mm f/1.2 at f/1.8. ("http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=105&amp;Camera=453&amp;Sample=0&amp;FLI=0&amp;API= 0&amp;LensComp=403&amp;CameraComp=453&amp;SampleComp=0&amp;FLIComp =0&amp;APIComp=3)


But that's normal because the f/1.2 has to be that soft in order to be optimized for bokeh. But in your case, it seems like the 70-200 is soft because of a defect, not as a purposeful part of the design. [:D]

[Alan]

For example, the $100 50mm f/1.8 beats the $1500 f/1.2 in corner sharpness at *every* f-number:


50mm f/1.8 at f/1.8 vs 50mm f/1.2 at f/1.8. ("http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=105&amp;Camera=453&amp;Sample=0&amp;FLI=0&amp;API= 0&amp;LensComp=403&amp;CameraComp=453&amp;SampleComp=0&amp;FLIComp =0&amp;APIComp=3)



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At 1.8, it looks pretty darn good in the center and mid-frame, too! [Y]

[andnowimbroke]

the $100 50mm f/1.8 beats the $1500 f/1.2 in corner sharpness at *every* f-number


Couldn't they now use the microadjustment to make it soft rather than having a special lens, or does that not help?


@OP:If you wouldn't have sent it in to Amazon for a new one,I don't think Canon covers the shippingTO the factory for repairs under warranty. They advise you send the broken item insured and trackable. I think it cost me $70. When repaired, they will send it back the same way..not the "broken" part.


Greg

[Daniel Browning]

Couldn't they now use the microadjustment to make it soft rather than having a special lens, or does that not help?





They could, but it wouldn't help, because it takes a certain kind of softness to improve bokeh: undercorrected spherical aberration.

[Elon Gane]

Thanks again everybody!


I have done more testing and it turns out that the soft corner problem is just at close focusingdistances only, When I tested myCanon 70-200mm f/2.8 L IS II with myCanon 55-250mm f/4-5.6 IS focusing at the Moon in the corner, My70-200mm f/2.8 is a lot sharper then my55-250mm f/4-5.6. But then at closefocusingdistances my 55-250mm f4-5.6 is sharper then my 70-200mm f2.8 in the corners. Should it be that way?


Should I still return myCanon 70-200mm f/2.8 L IS II?

[Wojciech Drzazgowski]

Possibly a stupid question but... did you have the IS on when you shot from the tripod? I believe you should turn it off as it would actually try to compensate for a movement of the lens that is not there. Give it a try and see whether it makes any difference.


Good luck!

[neuroanatomist]

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Possibly a stupid question but... did you have the IS on when you shot from the tripod? I believe you should turn it off as it would actually try to compensate for a movement of the lens that is not there.
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The IS on this lens (as on most newer lenses with IS) is tripod-sensing, and disables itself when the camera/lens is on a stable support. However, if the tripod isn't a good one, the vibrations might not be reduced enough for the lens to determine that it's mounted on a tripod.






But then at closefocusingdistances my 55-250mm f4-5.6 is sharper then my 70-200mm f2.8 in the corners. Should it be that way?


Should I still return myCanon 70-200mm f/2.8 L IS II?





How close is 'close'?


You're probably going to shoot things other than the moon. I think the bottom line is if you're seeing soft corners at distances you intend to shoot, then get it fixed/replaced.

[Elon Gane]

Turning IS on or off doesn't seem to make any difference.





By 'close' I mean around the minimum focus distance.A lot of my photos I take are near the MFD. I think I will return it for a new one.

[HDNitehawk]

Should I return my copy for a new one or not?





I have never bought a lens that I didn't immediatly take it out of the box and start testing it to death. Every time I ask myself is it as sharp as it should be. After a week goes by I usualy decide the lens is acceptable and it wasjust me worried I might have spent thousands on a lens that was a bad copy.


I have only hadone L lens that I decided it wasn't acceptable and sent it back. It was a 24x70L, and even after I got it back I still think its to soft.


My advice is, make sure you know the return policy. Don't wait to long and if you really feel it is to soft don't heasitate to send it back and get another copy. I wouldn't send it in for warranty work because if it comes back like the 24x70L I have, it may not be correted. Get the new copy not the warranty work.

[canoli]

maybe this is a stupid question but... should we really expect extreme corners to be sharp at 100% on an LCD/CRT?

[JJphoto]

maybe this is a stupid question but... should we really expect extreme corners to be sharp at 100% on an LCD/CRT?
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no, but if it's a EF lens on a 1.6X body, it will bother me a little.

[Sheiky]

maybe this is a stupid question but... should we really expect extreme corners to be sharp at 100% on an LCD/CRT?






If that is what the ISO-charts on different reviews show us, I guess we can also strive to get the same results at home, so yes...


And there is really a big difference between soft, acceptable sharp and true sharp. After that it becomes true pixel peeping [A]

[bob williams]

<span>But I could send it to Canonfor adjustmentright? Would the warranty cover the costs?


I have had 4 experiences with the Canon service center, three of which were for lens calibration/adjustment. They never charged me a dime for those. So I will say yes,the warranty will cover the cost---if it is still under warranty.


Also, You paid $2000+ for that piece of glass---if you have questions or dissapointments, send it back to Canon and let them tell you it either needed calibration/adjustment or that it meets specification. Each time I have returned mine for this, they always came back with some sort of adjustment and working better than they did before. We have to remember that no matter how good these lenses are, they have gone through thousands of miles of abusive cargo handlers and the liklihood of knocking something out ofadjustment is fairly high.


For what it's worth, All 4 times I have sent my lenses out, they have been returnedin about two weeks (California Service Center).


Just my 2cw.


Bob

[canoli]

Doesn't Canon ask you for the body as well when you send in a lens for "recalibration"?


I read somewhere that front-focus / back-focus issues can only be resolved when you have both the lens and the body, and that they may be able to correct it for that lens/body combination - but your other lenses may perform differently after the adjustment. That's what's so great about bodies with the micro-adjustment feature - you can do it yourself.


I guess maybe for soft corners and other problems they can work with just the lens...(?)