Focus Issue on New Canon 135mm f2 L ?

Luxologist wrote:

Hey All,

First time posting here, so I hope this is not in the wrong forum.

I recently added the Canon 135mm f/2 L to my lens arsenal and took it out today for it's second shoot. I get back to my office tonight, look at the images and I'm really bummed. Out of almost 300 images taken, only a handful are in focus. I don't get it. I used the lens for the first time about a week ago, and I got great results. So I hope someone can shed some light here.

Here's a breakdown of my set up:

Body: Canon 7D MkII

Lens: as stated above - Canon 135mm f/2 L

Back-button focusing. Both images used natural light.

First Image -

Exposure: 1/250 @ f2.2, ISO 100, Spot Metering, Manual Exposure.

No editing has been done. This is right out of camera via Lightroom.

Today's Image -

Exposure: 1/250 @ f/2.8, ISO 640, Partial Metering, Manual Exposure.

It will be hard to see on a small image, so if you can blow it up, go for it. If you can't see it, the second image looks out of focus. Almost everyone of my images of this girl looked out of focus. I have no idea why. Focus point every time was the the eyes, or bridge of the nose, right in between the eyes. Not all images were shot with an ISO of 640. Before I lost much of the ambient light, I was at 100-200 ISO, and had the same problem.
I really appreciate any help I can get. I'm really bummed as I won't be able to present more than 1 or 2 images from this session.

Thanks!!

I used to own the 135L and mine did require a few clicks of MFA to correct for a front focusing issue . I seem to recall it required about +6., so not an insignificant amount of MFA required to fix my issue. Once I dialed in the MFA adjustment, it made a significant difference in terms of sharpness.

So, as some others have suggested, I would suggest testing the lens to see if it requires MFA in order to dial in the sharpness....to rule this out first as it would seem to me to be the likely culprit. BTW....almost every lens I've owned has needed some MFA....especially on my 7DII (ie for some reason the lenses always need more on my 7DII than on my 5DII).

Luxologist wrote:

A simple explanation would've been sufficient. However, read a few of the replies and you'll see, adding a tripod to the equation was not the implication. I'm not being over-sensitive, I'm annoyed at those who post holier-than-thou replies, or make insinuations that a person is ignorant, or on some level beneath them.

I read them and disagree, there were some that were a bit less than polite, but for an internet forum, it really isn't bad. When the train comes off the tracks it gets pretty horrible. People are far less polite on the net than they would be in person, sadly.

Ignorant isn't a bad word, it simply means uninformed about something. If you are here asking for advice it would follow that you might be ignorant about some of these things. No one here knows how much you know, etc...so I'm just pointing out that typically responses assume that you know nothing at all. I won't deny that there is an arrogant subculture on this (and every other) internet forum, but I still don't see it in many of the replies in this thread, personally.

I never once stated or implied that I was a perfect photographer and that I suspect my gear has a problem. Not even close. I expressed a concern over a brand new lens that is exhibiting a focus issue I've not seen on my other lenses. Now, that being said, with the exception of my 85mm, all my other lenses have been zooms.

Yeah, even zooms though can certainly have issues. I don't think it's an issue of zoom vs primes, more of an issue of thin depth of field and tolerance of accuracy. 135mm f2 has pretty thin DOF, so when there's a miss you know it! And if something is a little out of calibration you have more misses. But the same can happen at 200mm f2.8, for instance, at some distances, because the total DOF isn't a lot. So all kinds of things come into play that you wouldn't see at say, f4 or f5.6.

The test that I would recommend is on a tripod see if it behaves consistently at different distances, if so then micro-focus adjustment can resolve any issues. If not, then you'll need to talk with Canon about it.

So, if there is a technical issue that I need to learn or be aware of with prime lenses of this nature, then that's why came for advice. I have recently decided to switch to all primes so I get there will be a learning curve to some degree. I just thought this would be a good place to get it all sorted. Again, I seem to have been mistaken. Thank you for your input. I will look into micro-focus adjustments.

Certainly primes are a little different, and I personally find them more enjoyable when I have the choice. There are a lot of good members here from whom you could get some good information, but of course there are others as well...it's the internet.

Luxologist wrote:

Doug_PS wrote:

Luxologist wrote:

Hey All,

First time posting here, so I hope this is not in the wrong forum.

I recently added the Canon 135mm f/2 L to my lens arsenal and took it out today for it's second shoot. I get back to my office tonight, look at the images and I'm really bummed. Out of almost 300 images taken, only a handful are in focus. I don't get it. I used the lens for the first time about a week ago, and I got great results. So I hope someone can shed some light here.

Here's a breakdown of my set up:

Body: Canon 7D MkII

Lens: as stated above - Canon 135mm f/2 L

Back-button focusing. Both images used natural light.

First Image -

Exposure: 1/250 @ f2.2, ISO 100, Spot Metering, Manual Exposure.

No editing has been done. This is right out of camera via Lightroom.

Today's Image -

Exposure: 1/250 @ f/2.8, ISO 640, Partial Metering, Manual Exposure.

It will be hard to see on a small image, so if you can blow it up, go for it. If you can't see it, the second image looks out of focus. Almost everyone of my images of this girl looked out of focus. I have no idea why. Focus point every time was the the eyes, or bridge of the nose, right in between the eyes. Not all images were shot with an ISO of 640. Before I lost much of the ambient light, I was at 100-200 ISO, and had the same problem.
I really appreciate any help I can get. I'm really bummed as I won't be able to present more than 1 or 2 images from this session.

Thanks!!

I used to own the 135L and mine did require a few clicks of MFA to correct for a front focusing issue . I seem to recall it required about +6., so not an insignificant amount of MFA required to fix my issue. Once I dialed in the MFA adjustment, it made a significant difference in terms of sharpness.

So, as some others have suggested, I would suggest testing the lens to see if it requires MFA in order to dial in the sharpness....to rule this out first as it would seem to me to be the likely culprit. BTW....almost every lens I've owned has needed some MFA....especially on my 7DII (ie for some reason the lenses always need more on my 7DII than on my 5DII).

Thank you for a well put, rational and supportive reply. Finally, a reply that leaves the ego at home. I have never had to MFA a lens, so I'm in the dark on this topic. First time for everything, right? I'm sure I can find various YoouTube videos on the subject, and I'll probably find a thousand different ways to do this, but, how did you do it. Since you are familiar with the lens and the body I'm using, I'm interested in knowing how YOU did it.

Thanks again!

No problem...glad to help.

I'm a "fly by the seat of my pants" kind of guy when it comes to testing my lenses for MFA. Nothing fancy for me. You can spend money on systems that will help you find MFA (Focal, LensAlign, etc....). Others on this forum are much more able than me to expand on these.

For me: I'll just pick a nice contrasty target (i.e. On the ground, etc...) in the same lighting conditions I typically plan to shoot ( i.e. Outdoor light, etc...my understanding is that different lighting conditions might affect auto focus). I typically shoot at 45 degrees to the target (i.e. helps me see front/back focusing results better). I'll take about 3 shots each at -10, -5, 0, +5 and +10 MFA to start. By comparing the -10 and + 10 pic's, I can usually tell easily where the problem is....if any exists ( i.e. either Front or back focus). Then I compare the -5 and +5 pics to see if it leads me to the same conclusion. From this, I might conclude the lens is front focusing, so I repeat the test by zeroing in on only positive MFA adjustments (i.e. To move the focus point back) and narrow it down until I find the MFA adjustment that works best.....then always test on a real subject to see validate that there is an improvement. I typically don't spend more than 15-30 minutes or so testing....works for me.

Others on this forum recommend a method called Dot Tune. It's very simple (and free) and some claim very effective. Here is a link to a video:

http://youtu.be/7zE50jCUPhM

Focus on my 135mm f/2L is great. I bought mine used and it still works great. SO MUCH FASTER THAN 85mm f/1.2 II