How to get / test a good copy of a L lens?

[JerryBruck]

Marsu42 asked,

...-what is Canon service actually able to do?
* AF adjustment (Do I have to turn in my non-afma body with my lens)?
* sharpness / ca-improvments?
* Do they do it for free on warranty / how bad does a problem have to be to make them do it for free?

I've wondered about that also -- since they took the trouble to remove afma from our 60Ds, can and will they correct a mismatch, and at what cost, post-warranty?

 

[tom_webster]

For me there are two ways of looking at these issues. The first is that if a lens seems sharp and produces nice pictures then it is ok, nothing more to worry about. The second is that if you are spending a lot of money on purchasing expensive Canon L glass then you should expect it to perform as well as it should and that sample variation should be minimal to the point of being irrelevant.

Half the issue these days I suspect is the fact that it is so easy to pixel-peep and there are also so many internet forums which allow people to rave about the sharpness of their copies or to warn about issues that they have experienced, this then leads you to doubt the quality of the lenses that you have or possibly to expect too much.

I have just been through this process myself. I have a Canon 35L and had a 100L macro on my 5D2. Both performed flawlessly in my opinion and produce images a sharp as I would ever have expected. I then traded by 100L for a new 135L as I though this would be more use to me.

The 135 is great but its sharpness doesn't blow me away in the same way as the 100L did and the 35L still does. I have micro-adjusted it by +8 and this helps but though it still produces great/good images I didn't feel that it lives up to the 'sharpest lens ever', 'truely wonderful' comments that I read so much before purchasing.

Granted I am comparing it to a macro lens known for sharpness and the 35L which is also very highly rated but something still doesn't sit quite right when I have spend many hundreds of Pounds on the lens.

End result, the lens has been sent in under warranty for calibration (to my camera body which has previously been checked calibrated by Canon) so I am hoping that it comes back working better. If it does not then I hope I shall rest happy knowing that it is at least as good as Canon think it should be.

For me then I guess the question is whether when buying L glass you should almost by default send the lens in for checking/ calibration. This seems ridiculous but without doing so I don't really see how you can know whether the lens is working as well as it should. It may work great but could it work better?

If you spend as much as these lenses cost then I would expect it to work as well as possible. For me, and most others I suspect, I have no practical way of comparing my 135L against other copies on my camera body or against the same or other copies on different bodies. You therefore either accept it as it is or have it tested by the experts.

 

[Marsu42]

Marsu42 - would be interested on how you get on...

I've written about my test and experience with the lens here http://www.canonrumors.com/forum/index.php/topic,3359.60.html at page 5

 

[drmikeinpdx]

I've spent way too much time testing lenses and sending them in for adjustment. It is the autofocus system that causes most of the problems, but poor assembly of lens elements seems to occur occasionally. The unreliable performance of the current autofocus system (both lens and camera functions) is a real problem for serious photographers.

I don't know of an easy and practical way to determine the inherent sharpness of a particular lens, other than shooting lots of photos under good conditions (tripod, etc...) and pixel peeping.

I have developed a quick autofocus test that works for me. I can describe it if anyone wants to know more.

If a lens focuses well with my camera body, then I try to evaluate the sharpness. Some lenses are sharper than others. The vast majority of photography that I do involves people, not landscapes, and the photos are almost all posted on the web, not made into prints. I really don't need lenses that are as crisp as breadsticks and images that hurt the eyes with razor sharp details.

I may lust in my heart for a lens that blows me away with sharpness on every shot, but in reality it is not worth chasing. The people who view my photos would not recognize it anyway.

Just my opinion!

Mike in Portland, OR

 

[Marsu42]

I have developed a quick autofocus test that works for me. I can describe it if anyone wants to know more.

Please do

I may lust in my heart for a lens that blows me away with sharpness on every shot, but in reality it is not worth chasing. The people who view my photos would not recognize it anyway.

That's the difference - the only one who views my photos is me ... I am macro-infected and am using it as a microscope with 18MP camera behind it. However, even with a tele lens I would like to see detail at 100% that I wasn't able to see with my bare eyes if possible - that's mostly why I want to get a L lens, not because of any 2.8 aperture or quick af (although a precise af does help getting sharp pictures, just as you wrote).

 

[Stu_bert]

Marsu42 asked,

...-what is Canon service actually able to do?
* AF adjustment (Do I have to turn in my non-afma body with my lens)?
* sharpness / ca-improvments?
* Do they do it for free on warranty / how bad does a problem have to be to make them do it for free?

I've wondered about that also -- since they took the trouble to remove afma from our 60Ds, can and will they correct a mismatch, and at what cost, post-warranty?

In the UK, when I have my lenses adjusted to the body (started when I had the 5D), Canon do adjustments in the lab which stores it separate to the AFMA data. The technician I spoke to claimed it is more accurate. I can't speak for the lens adjustments as frankly I've only ever asked on one, and it was still rubbish after

 

[StevenBrianSamuels]

I use to test all my lenses for a few days after buying until I noticed how much I agonized over it and decide to just go out and shoot. Made life a bit simpler.

 

[EOBeav]

I know of a couple of landscape pros who 'only' have the 70-200mm f/4 L, non-IS. I shoot with it, and it's one of my favorite lenses. My experience on an XSi is that if you're shooting indoor sports or something similar, you'll have a tough time raising the ISO enough to get a decently sharp image. On a tripod, though, that's a whole different story. Some of my best shots have come from this lens, and I'm always amazed at the amount of detail I get with it. If you get it, you won't be sorry. And you don't have to apologize for having it instead of the f/2.8 IS. Just sayin'.