Some focus issue on cz 16-80

[PNOYSG]

Hi Bros....

I got a 2nd hand cz 16-80 which after using more often realized it has some F/B focus issues..:embrass:
Eventhough I locked in the subject the result still OOF, which I thought CZ lenses don't have such issues since its a CZ..
This happens only on AF since everytime I used MF I do FOCUS CHECK LV zoom in the subject and adjust..
Does any of you guys have this experienced on your CZ before?

here a photo for reference, focus locked on the face of the subject:

 

[kei1309]

at this resolution can't really see the difference.

you would need the high-res image for the experts (you know who) to do the necessary checking

 

[davidlam001]

Recently i found some back focus when I took picture with my CZ lens.
I tot it was the lens problem, but i has the same amount of back focus when i tried another lit lens. In the end I sent my camera for calibration.

Getting back the camera today, hope they get the focus in.

 

[taeivon]

I just sent in my A33 to the service center for back focusing issue too. Posted my "findings" in this forum 2 weeks ago. Sony has calibration issue at their factory?

 

[NoS77]

Appears that my 16-80 has some front focusing issues as well. will do more test shoot before concluding

 

[stonefish35]

Confirm the front or back focusing issue with shots done with a focusing chart, tripod mounted etc. And try with different lenses to see if its a lens or body issue

 

[PNOYSG]

wow!!! would the body will have focus issues as well? I thought f/b focus issues is only for the lenses....

will try my cam body with other lenses...

 

[Rashkae]

wow!!! would the body will have focus issues as well? I thought f/b focus issues is only for the lenses....

will try my cam body with other lenses...

Common cause is body actually... The alignment of the AF module must be *exact*.

In your pic though, it looks like the camera selected the background because of the higher texture.

What focus point did you use? Did you try specifying centre AF point? If yes, then look where the centre really is and you'll see the focus is correct.

 

[PNOYSG]

@Rashkae
- the focus point I used on this is LOCAL as I always been using..

 

[Rashkae]

Local, and you set it to the face, right? Now consider the relatively small size of the face, compared with the massively textured background...

If the focus area had targeted her t-shirt and that covered most of the AF sensor, I don't think the AF sensor would have been "confused".

 

[Rashkae]

@Rashkae
- the focus point I used on this is LOCAL as I always been using..

Ok, using the AF sensor map as an overlay on your image, I can see the local AF sensor area, if targeted on her, would include about 50% of the background and 50% of her. The background is heavily textured compared to the subject so that gets favored.

Do you have any other images that show this behavior? If you do centre focus do you get the same issue?

 

[gongong]

This is my copy of cz1680. I always use the center spot to focus, lock it, then recompose.

I find it sharp.
What do the bros here think? Sharp?


Photos been resized by Flickr.

The lavender in the center is where i choose to focus then recompose, so the lavender in the center will not be directly in the center of the shot.

This shot, i focus the the 2nd bunch from the left. so the direct center of this shot is not where i had focus as i recomposed.

 

[PNOYSG]

Ok, using the AF sensor map as an overlay on your image, I can see the local AF sensor area, if targeted on her, would include about 50% of the background and 50% of her. The background is heavily textured compared to the subject so that gets favored.

Do you have any other images that show this behavior? If you do centre focus do you get the same issue?

Now I got what you mean..

I realized that all those sharp pics are centre focus

 

[gongong]

by the way, I forgot to mention.

If you camera has autofocus continuous which means it will try to keep focus of a moving subject, then you might want to switch it to AutoFocus Single.

I always use autofocus single, so that when i half press the shutter to lock the focus, then when i recompose, the focus on my subject remains.

Coz if you use AF-C, even though you half-press shutter to lock focus, but when you recompose, your camera might think that the subject is moving, hence readjust the focus to where the sensor is pointing.

 

[PNOYSG]

by the way, I forgot to mention.

If you camera has autofocus continuous which means it will try to keep focus of a moving subject, then you might want to switch it to AutoFocus Single.

I always use autofocus single, so that when i half press the shutter to lock the focus, then when i recompose, the focus on my subject remains.

Coz if you use AF-C, even though you half-press shutter to lock focus, but when you recompose, your camera might think that the subject is moving, hence readjust the focus to where the sensor is pointing.

IC,::think::think::think:

Thanks bro now I know.....

 

[dandoodle]

pretty sharp photos. Are you pleased with your lens so far? Im tossing between getting this and a prime lens (CZ 24mm f2)