auto focusing problem

hi,
does any of the following have auto focusing issue

70-200 mm 2.8

24-105mm f4

17-40mm

I received all three today and it seems to me that they have trouble auto focusing especial at the maximum zoom range

What body? What AF mode? How many AF point active? What subject?

show pics
speak w data ...

I have 17 - 40 and 24 - 105 70 - 200 f4 ... they work fine.

As mentioned, we need more info. What exactly does "focusing issue" mean?

I am using 550D

focus mode: one-shot af

by issues I mean it struggles to focus

I will upload pics as soon as I have a chance to take the camera out

EL_PIC wrote in post #12023486
show pics
speak w data ...

I have 17 - 40 and 24 - 105 70 - 200 f4 ... they work fine.

I am not implying that they are bad lenses... I just asked a question

Any AF lens will struggle in low light, a flat subject, and sometimes near MFD.

abuha wrote in post #12023769
by issues I mean it struggles to focus .

There are two main reasons I can think of for a camera to have focusing difficult and it's always the camera. A lens is not capable of determining focus, all it does is moves per the camera's instructions.

First, there is not enough contrast in the target. The way the autofocus works is by looking for a high contrast edge ad determining focusing needs from there. Second is that there is not enough light to focus. Does the camera/lens pair have issues all the time, outside in full sun included?

Do you have any lens that does not show the same issue?
I guess it is lack of light or lack of contrast, but it would be easier to see once you have uploaded the photos.

gasrocks wrote in post #12023790
Any AF lens will struggle in low light, a flat subject, and sometimes near MFD.

The probable cause could be any one (or all) of the above..

If you are using one shot AF either you or the subject may have moved slightly between acquiring focus and taking the shot. Try A1 Servo

I have all the lenses you mention and after a little bit of MFA they are all superb. Even before I bothered to MFA them they were pretty darned good

are you sitting in a dark living room playing with the new toys? Keep in mind that you need a certain amount of light and contrast to focus, and those lenses also have minumum focusing distances so if its too dark or you are too close you wont get anything.

abuha wrote in post #12023471
hi,
does any of the following have auto focusing issue

70-200 mm 2.8

24-105mm f4

17-40mm

I received all three today and it seems to me that they have trouble auto focusing especial at the maximum zoom range

more likely it's your camera body. hard to believe all 3 would have the same problem unless it's the body.

I think the OP has left the building.