How to Check AF Issue on 7D

[shazie]

aah... i forgot about that part. thanks for the clarification!

If you're using the same lens e.g 85f1.8 on FF, you have to walk closer to get the same size object in your photo. Hence, you will get thinner DOF.

 

[jdbatino]

If you're using the same lens e.g 85f1.8 on FF, you have to walk closer to get the same size object in your photo. Hence, you will get thinner DOF.

Thats' right. Also, a 85mm 1.8 on crop and 135 2 on a full frame will produce the equivalent field of view.But the full frame will have more "bokeh" because it uses a longer focal length with almost the same aperture.

But it doesnt matter, the 85 1.8 bokeh on your 7D is more than enough. :bsmilie:

 

[sabee]

If you're using the same lens e.g 85f1.8 on FF, you have to walk closer to get the same size object in your photo. Hence, you will get thinner DOF.

But if you perform a 1.6x crop on the computer instead of working closer to the subject, you get the same result as using the lens on a 1.6 body right? Is the DOF the same then?

 

[daveloo28]

Hi all,
I just got my 7D 2weeks ago and i think i'm also having problem with my camera.Mine is 04xxx batch.Took some shots with my canon 50mm 1.8 mkll lens mounted on a tripod(all @1/8s F2.8 ISO400) and the pictures turn out like not sharp.Dont know if this is done the right way or not but here are the pics.
1.Spot metering w/o lens micro adjustment

2.Spot metering w -5 lens micro adjustment

3.19Pt AF w -5 lens micro adjustment

Thanks in advance

 

[lightning]

You might want to use a better piece of glass.

 

[GFONG]

Hi all,
I just got my 7D 2weeks ago and i think i'm also having problem with my camera.Mine is 04xxx batch.Took some shots with my canon 50mm 1.8 mkll lens mounted on a tripod(all @1/8s F2.8 ISO400) and the pictures turn out like not sharp.Dont know if this is done the right way or not but here are the pics.

Just wondering whether it is the lens problem or the camera problem. Of course, the camera may have the AF issue, but most of the time are the lenses problem.

 

[sjc6969]

daveloo28

Assuming your spot metering pic is using the centre point, you should try the same setting with the other 18 focus points to see if they are sharp. I think when the 19 points AF was used in the last shot, the focus points are different resulting in a soft pic.

Of course I might be wrong...:embrass:

 

[daveloo28]

Thanks all,
I do have another lens.It's a Sigma 18-50mm 2.8 EX DC Macro.This too gave me the same soft/blur image.I thought maybe it was the 3rd party lens,that's why i took the same pictures with the canon lens too.Set both lenses at 50mm focal length with the same F/stop and ISO.Sigh!
Thanks a lot guys..appreciated it.

 

[evilorgi]

wow... this AF issue certain makes me think twice about buying a 7D... omg...

 

[hobbit6003]

The auto 19 AF pts, unfortunately, doesn't focus accurately 100% of the time on flat subjects, even in a good set. I guess it is not designed to be used this way.

 

[hsloo]

Hey.... i found that my 7D serial number is 028xxxxx, what should i do? Bring all my lens and 7D to CSC for calibration?

Do you think i can shout for an exchange with CSC?

Very sad very sad.......

 

[hobbit6003]

Hey.... i found that my 7D serial number is 028xxxxx, what should i do? Bring all my lens and 7D to CSC for calibration?

Do you think i can shout for an exchange with CSC?

Very sad very sad.......

What's wrong with your serial no? If your camera is alright, why do u want to get it exchanged?

Pls go test extensively first before crying wolf. For those of us who had AF issues, we tested the camera and lenses extensively before bringing it in to CSC. I've shot no less than 4000 shots both under controlled and real time environment before we concluded that there's indeed an issue, and had the body exchanged.

Serial no doesn't mean much, so pls dun be so one tracked mind.

 

[hsloo]

Anywhere there is the test procedures somewhere i can follow?

 

[doodah]

Anywhere there is the test procedures somewhere i can follow?

Try this:

as well as this:

I also own the rather expensive LensALign Pro system. Results are not different than using three 9V batteries.

Alternative method - follow this link

'Official' Canon recommendation on how to use micro-adjustment - see this.

Auto-area algorithm : FAIL.

 

[faineant]

Anywhere there is the test procedures somewhere i can follow?

Mount the camera on a sturdy tripod, set the lens to it's max aperture and half press the shutter to focus on a contrasty target with fine detail about 25 to 50 times the set focal length from the camera. For a 50mm lens this would be 25 x 50mm = 1250mm / 25.4 = 49 inches or about 4 feet. Anywhere between 4 and 8 feet is fine. Defocus the lens and half press the shutter.

Now enable liveview and press the magnify button twice for 10x. Look at the image and then half press the shutter again and hold the half press while the camera focuses using liveview contrast AF. Does the image appear sharper now? If so turnoff liveview and half press the shutter again, enable liveview, magnify the image and tweak the focus ring back and forth to see if the lens is back focusing or front focusing.

There should be a consistent result that will allow you to experiment with + and - settings in the AF microadjust menu to obtain consistently sharp results. There's really no need to even take a shot on the memory card. It takes some time but you get very good at it and it's well worth the effort for sharp images.

 

[hsloo]

Thank you all, will definitely try it......

 

[AJGun]

wow... this AF issue certain makes me think twice about buying a 7D... omg...

close your eyes and just buy it if you already have decided
i've got mine this way too. if you keep reading here and there definitely until 7Dmk2 also will not buy hahaha.....

 

[labert]

Hmm it is scary with some many having AF issues till I was so worried. My 7D is the 04xxxxx no.

Some shots:

19 pts. AF, One Shot.

Spot AF, AI Servo locking onto the Orang Utan's face.

Center Zone AF, AI Focus.

Looks ok? So far many shots I took are satisfactory to me.

 

[hobbit6003]

Hmm it is scary with some many having AF issues till I was so worried. My 7D is the 04xxxxx no.

Some shots:

19 pts. AF, One Shot.

Spot AF, AI Servo locking onto the Orang Utan's face.

Center Zone AF, AI Focus.

Looks ok? So far many shots I took are satisfactory to me.

I think you've got to get your technique right first. From all these shots, I feel that you've still got some way to go before you can even start to evaluate your AF quality.

 

[faineant]

Hmm it is scary with some many having AF issues till I was so worried. My 7D is the 04xxxxx no.

Looks ok? So far many shots I took are satisfactory to me.

This is one of mine taken handheld, at 200mm, single point focus, one shot AF. The bird was bobbing its head. Just click on the photo for a larger size.

Personally, I never use Auto AF, because the camera's choice of focus points is never what I want 85% of the time (unless its a simple subject)

The orang utan shot, what was your shutter speed?

Why not spot focus on the spider?