70-200 2.8 IS + Micro Adjustment....

Curious to see what everyones setting for Micro Adjustment with this lens is.

Right now I'm at +5 and everything from 70-135 is perfect, but from 135-200 I get front focusing. Does the lens need to be sent in for calibration or does this happen with everyone else?

What procedure did you use? I tried Northligh Images as well as focusing charts at 45 degree angle, but the only way I could come up with any consistent conclusions was using a wine bottle - and viewing the lettering at 100% at each microadjustment level. I did tests at 200 and 150mm. Focusing to infinity first, then auto-focusing, 3 shots at each of the 21 levels (from 0 to +20), plus 3 shots using manual focus on 10x Live View. The optimal setting seemed to be in the +10 .. +11 range, but quite frankly, there seems to be a wide range where the sharpness plateaus, and I found it quite hard telling the difference between +7 and +15, for instance (there was definitely a visible difference between +10 and 0). Maybe that is due to insufficient distance that I was using: only 4 meters or so in my living room. I also don’t know what I am going to do with the lens yet, I can still return it to the store, but what are the chances that my next copy will be much better? There used to be a thread here about people’s microadjustment settings for different lenses, and my impression was that around 70% of all lenses needed to be adjusted by at least 5 (on scale of -20 .. +20) either way. If that’s the case, it’s quite likely that my next copy would not be spot on, either.

Were your results pre-adjustment (i.e. at 0) satisfactory or completely off? Mine were disappointing, although this could have been me using the lens in a wrong way.

In the pre-microadjustment days, how did people deal with this?? Did majority just put up with slight mis-focusing, or did most people go to Canon for servicing/adjusting at some stage??

I can see that at 200mm, f/2.8, 4 meters, DOF is around 4 centimeters. Does anyone know what distance (i.e. shift in the center of DOF band) is going from 0 to +20 microadjustment equivalent to?

Actually I don't use static "controlled" tests. I actually Micro adjust on the job, in the field based with my shooting style/ habits.

Its just recently I started using focal length over 135mm and started to notice the front focusing. The thing that bothers me is that its never consistent. Sometimes its spot on focus and others its off. Right now majority of it is off.

If I adjust it so at long focal length its spot on, I'm afraid at wide side of the lens it will back focus...

M Powered wrote in post #7772663
If I adjust it so at long focal length its spot on, I'm afraid at wide side of the lens it will back focus...

If sent to Canon for adjusting, do they do anything more over what is available through the microadjustment feature in 50d (or other bodies)? I mean, will they be able to adjust the two ends (70 and 200mm) differently, which is not possible for us using the camera body feature?

I am still wondering whether I should send my copy back to the dealer, send it to Canon for adjusting, or just keep it and try microadjusting myself.

Send it in or exchange it. If you are happy with the sharpness of the glass wide open I would send it in, since the next one might focus well and not be as sharp. That's what I did with my Tamron which focused inconsistently but was VERY sharp wide open.

You here about lenses focusing fine at long distances but crap at short distances often, or vice versa.

Microadjustment isn't going to fix it. They can program the chip inside to alter how much it moves at different distance points, I would imagine. Something you can't do with camera, built in, micro adjustment.

I have a 40D and all my lenses focus fine at all settings. Fortunately they didn't need to be sent in except the Tamron. It works GREAT, now.

pawelx wrote in post #7772684
If sent to Canon for adjusting, do they do anything more over what is available through the microadjustment feature in 50d (or other bodies)? I mean, will they be able to adjust the two ends (70 and 200mm) differently, which is not possible for us using the camera body feature?

I am still wondering whether I should send my copy back to the dealer, send it to Canon for adjusting, or just keep it and try microadjusting myself.

If you can exchange it, then do so. I went through several copies of the 24-70 to find the perfect one.

Had an issue with mine and posted here about it a few weeks back.

The copy I had was pretty weird because I would almost see "double" of my subject with a slight blur. Knew it was something wrong with the lens because my 24-70 was tack sharp. Sent it in and they said a part was loose so it couldn't focus correctly and they also replaced the IS assembly.

M Powered, where do you buy your lenses from? Anyone know if B&H allows exchange of lenses that the buyer consider to be not tack sharp?

nestle wrote in post #7775940
Had an issue with mine and posted here about it a few weeks back.

The copy I had was pretty weird because I would almost see "double" of my subject with a slight blur. Knew it was something wrong with the lens because my 24-70 was tack sharp. Sent it in and they said a part was loose so it couldn't focus correctly and they also replaced the IS assembly.

M Powered, where do you buy your lenses from? Anyone know if B&H allows exchange of lenses that the buyer consider to be not tack sharp?

Got my lens a while back from a local camera store.

I know this double blur your mentioning, for me it only happens when it is out of focus.

You need to adjust it at the long end, most if not all zooms
are sharper at one end.

malla1962 wrote in post #7776121
You need to adjust it at the long end, most if not all zooms
are sharper at one end.

Adjust in the long and its off in the wide. Only true balance you can get is if Canon does it.

pawelx wrote in post #7772635
What procedure did you use? I tried Northligh Images as well as focusing charts at 45 degree angle, but the only way I could come up with any consistent conclusions was using a wine bottle - and viewing the lettering at 100% at each microadjustment level. I did tests at 200 and 150mm. Focusing to infinity first, then auto-focusing, 3 shots at each of the 21 levels (from 0 to +20), plus 3 shots using manual focus on 10x Live View.

what are the manually focused shots for? just to see if your lens is sharp at all?

also, general question, does (-) move the focusing plane back, and (+) move it forward (towards the photog?)

No matter what my settings are I'm getting blurry shots. I've tried to go from -20 to +20 and +1 is the best I could come up with but nothing seemed in focus (when compared to a manual focus shot). I think mine is going back to B&H.

Sfordphoto wrote in post #7776915
what are the manually focused shots for? just to see if your lens is sharp at all?

also, general question, does (-) move the focusing plane back, and (+) move it forward (towards the photog?)

Yes, I use manual focus to confirm that the lens is sharp ( I think it is - I will post some images later on today when I return home, bus stands from around 20meters distance, where I can read the bus schedule written in lettering of no more than 20pts etc.).
I think that my lens is front-focusing at long end, and positive (+) microadjustment seems to give better results than no adjustment.

EternalLife wrote in post #7777308
No matter what my settings are I'm getting blurry shots. I've tried to go from -20 to +20 and +1 is the best I could come up with but nothing seemed in focus (when compared to a manual focus shot). I think mine is going back to B&H.

Can you post some examples? I find it difficult to tell between "not sharp" and "out of focus" sometimes. Obviously, if you're looking at 100% view then there will be some blur visible around letters which are 3mm tall and 4 meters away from you. Without another L lens to compare, Or in fact any lens in this focal range, I sometimes don’t know what is unsharp, and what expected due to extreme pixel-peeping. I was shooting a wine bottle for my tests https://photography-on-the.net …1&highlight=18-270&page=2 from short distance (around 4m), today I'll go and shoot timetables on bus stands outdoors from a greater distance (around 15m). I posted 0 adjustment, optimal adjustment (in my case, around +10), and best result of manual focusing.

pawelx wrote in post #7780298
Can you post some examples? I find it difficult to tell between "not sharp" and "out of focus" sometimes. Obviously, if you're looking at 100% view then there will be some blur visible around letters which are 3mm tall and 4 meters away from you. Without another L lens to compare, Or in fact any lens in this focal range, I sometimes don’t know what is unsharp, and what expected due to extreme pixel-peeping. I was shooting a wine bottle for my tests https://photography-on-the.net …1&highlight=18-270&page=2 from short distance (around 4m), today I'll go and shoot timetables on bus stands outdoors from a greater distance (around 15m). I posted 0 adjustment, optimal adjustment (in my case, around +10), and best result of manual focusing.

This example was taken with the 50d and the 70-200 f4L IS. Shot taken at ISO200, 200mm, f4, 1/80.
The target was the ruler, located at a 45 degree angle, at about 2.4 meters, and the focus was the black vertical line at the 8 inches marker. You can see the small DOF, which on the cm scale goes from 19 to 21 cm. The MA will move this DOF range to the left (using +x) or to the right (using -x), but the main thing is that anything within the DOF range will appear on focus.
In this case, my opinion is that my copy is quite on the target and does not need any adjustment.

Miguel

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