How to micro adjust??????

Hey fellow potn members. I just want to know if anyone here can give me links on how to micro adjust my lenses on a 7d. I do have the "focus genie" but i do wanna know how to use it properly. Thanks in advance!

I'm sure if you search this forum for microadjust you will find a bunch of links. There are several different methods with everything from using special focus charts to moire patterns on your monitor. Canon recommends testing with a subject distance no less than 50X your focal length. Also, for zooms they recommend using the longest fl.

here is one website some people use and it also describes some of the other methods out there.

http://www.northlight-images.co.uk …s3_af_micoadjus​tment.html

There are so many threads and links explaining the issue, but let my give you my experiment with a 70-200 2.8 IS on 5D mkII which should be basically the same in a 7D.
Installing the camera on a tripod (about 0.5m height), setting the focus on SPOT, setting the camera on MLU and 2s timer, f2.8 (for getting narrowest DoF), setting longest focal length on the lens, I put an A4 text in a distance of about 2.5m apart on floor.(text should be single font size printed to give you an scale abut focus deviation)
Aiming on specific line in the text I took first shot; then going to micro adjustment menu in the camera, I took next shots with different "+" and "-" adjustments. (making a list of adjustments vs. file number will help you later to apply final adjustment). I transferred taken shots to PC and observed the results at 100%. Next step will be applying the micro adjustment value corresponding to shot with most precise capture of the aimed line in the text.
I'm totally happy with result, I took these shots right after adjustment in different f numbers:

f8: http://www.pbase.com/k​_amj/image/110326510
f5.6: http://www.pbase.com/k​_amj/image/110361850
f3.2: http://www.pbase.com/k​_amj/image/110216423
f2.8: http://www.pbase.com/k​_amj/image/110213381

a related question:

what are the chances my lenses need micro adjust?

james_in_baltimore wrote in post #9951616
I'm sure if you search this forum for microadjust you will find a bunch of links. There are several different methods with everything from using special focus charts to moire patterns on your monitor. Canon recommends testing with a subject distance no less than 50X your focal length. Also, for zooms they recommend using the longest fl.

here is one website some people use and it also describes some of the other methods out there.

http://www.northlight-images.co.uk …s3_af_micoadjus​tment.html

hey thanks for the link, i'm actually using the focus genie atm...but the link was very helpful

K_AMJ wrote in post #9954854
There are so many threads and links explaining the issue, but let my give you my experiment with a 70-200 2.8 IS on 5D mkII which should be basically the same in a 7D.
Installing the camera on a tripod (about 0.5m height), setting the focus on SPOT, setting the camera on MLU and 2s timer, f2.8 (for getting narrowest DoF), setting longest focal length on the lens, I put an A4 text in a distance of about 2.5m apart on floor.(text should be single font size printed to give you an scale abut focus deviation)
Aiming on specific line in the text I took first shot; then going to micro adjustment menu in the camera, I took next shots with different "+" and "-" adjustments. (making a list of adjustments vs. file number will help you later to apply final adjustment). I transferred taken shots to PC and observed the results at 100%. Next step will be applying the micro adjustment value corresponding to shot with most precise capture of the aimed line in the text.
I'm totally happy with result, I took these shots right after adjustment in different f numbers:

f8: http://www.pbase.com/k​_amj/image/110326510
f5.6: http://www.pbase.com/k​_amj/image/110361850
f3.2: http://www.pbase.com/k​_amj/image/110216423
f2.8: http://www.pbase.com/k​_amj/image/110213381

thanks, very helpful

mike cabilangan wrote in post #9954913
a related question:

what are the chances my lenses need micro adjust?

If any are made by Sigma, pretty good.

I Have a 24L1.2II, 24F1.8 Sigma, 50F1.4, 85L1.2II, 135L2.0, 300L2.8nonIS and 70-300DOIS TC2X TC1.4X

Only 85L1.2II doesn't need to be micro adjust with 5DMKII ......
For other lenses it's from -5 till +17 (with stacked TC2X+TC1.4X)

I used many way to do it .. and it's quite tricky
http://photo.net/learn​/focustest/
http://www.komar.org/f​aq/camera/auto-focus-test/
http://www.slrgear.com​/articles/focus/focus.​htm

I could do perfect micro-adjustments with this tecknics ..
But since I bought lensalign I could confirm results, but new lenses are taking a few minutes to do it...
http://www.lensalign.c​om/ expesive but a real pleasure to do it.

I would say, that I don't understand how we can use a lens AF without doing any micro adjustment .. sharpness is so different due to front or back focusing... Don't buy any body that can't be adjusted by lenses unless you correct manually any AF!!!

mike cabilangan wrote in post #9954913
a related question:

what are the chances my lenses need micro adjust?

Very good. I think there was one lens in my lineup that didn't require MF adjustments - on my 7D. On the 5D2 every single one required a pretty strong adjustment (i.e. bad sensor distance alignment).

I see now with hindsight that what I attributed to bad quality glass on my older camera houses was probably just a question of AF adjustment. Canon quality control is unfortunately abysmal and not even their most expensive glass is consistently well adjusted.

How do you know IF your lens needs to be Micro Adjusted?

KRUSH wrote in post #9955235
How do you know IF your lens needs to be Micro Adjusted?

It's very easy, when you get sharper images with lifeview than with AF ... then you can with DPP by puting sharpness to maximum you can easily see if you have a front focus or a back focus...

KRUSH wrote in post #9955235
How do you know IF your lens needs to be Micro Adjusted?

You will see a consistent pattern where sharp focus falls either slightly behind (back focus) or slightly in front of (front focus) where the actual selected focus point falls in the frame.

There are variables of course that can make AF less effective:
- Lack of Contrast (Grey Wolf in the fog)
- Allowing the camera to choose the AF point (do it yourself!)
- "Focus and Recompose" when shooting wide open at extremely shallow DOF

I have a questions to do with microadjustment

The microadjustment that is made seems to have no units associated with the numbers so unless you have a camera with that abilty, you don't know how bad for example +17 is. I'd like to see some examples of images of an object taken before and after microadjustment. Or is someone able here to quantify these values.

Thanks Subby

hqqns wrote in post #9955268
I have a questions to do with microadjustment

The microadjustment that is made seems to have no units associated with the numbers so unless you have a camera with that abilty, you don't know how bad for example +17 is. I'd like to see some examples of images of an object taken before and after microadjustment. Or is someone able here to quantify these values.

Thanks Subby

I don't believe this would really be meaningful.

Because of manufacturing tolerances, my zero point will be slightly different than your zero point so my +5 won't automatically be +5 for you.

And remember too, you have tolerances for both the body and the lens so it's a "double floating zero point" as it were.

ETA: If you go out expecting to find flaws, you'll find flaws. FWIW, Across four bodies and 14 lenses since I first used a dSLR, I've never seen any iffy results that I could ever nail down as being exclusively hardware induced.
Digging into my own EXIF, I'll find shutter speeds that maybe were a hair too slow for optimal imaging as well as instances where I was on the ragged edge of MFD (minimum focusing distance) or shooting so wide open that a wobble by me or by my subject meant an OOF image (often all it takes is I lean in slightly while he/she does the same and OOF is the result.)

FlyingPhotog wrote in post #9955283
And remember too, you have tolerances for both the body and the lens so it's a "double floating zero point" as it were.

Understood. So what you are saying i think is that the tolerances of both the body and lens have a factor. But that tolerance even if floating will have a definate distance between specific body and specific lens.

In a perfect world the distance from "sensor to mount" and "lens optics to mount" will be exact and exactly in focus. These distances can both change so it makes sense to have microadjustment to correct for real world differences from the ideal.

So my question still is ignoring any zero points what does it mean to got+- a step. Does that make sense ?

hqqns wrote in post #9955327
Understood. So what you are saying i think is that the tolerances of both the body and lens have a factor. But that tolerance even if floating will have a definate distance between specific body and specific lens.

In a perfect world the distance from "sensor to mount" and "lens optics to mount" will be exact and exactly in focus. These distances can both change so it makes sense to have microadjustment to correct for real world differences from the ideal.

So my question still is ignoring any zero points what does it mean to got+- a step. Does that make sense ?

I see what you're getting at...

I can't say I've ever seen anyone quantify a measure for what each "tick" plus or minus equals. "Focus Charts" are generally in mm's but whether or not each tick means one mm of change...?