f/4 and Autofocus limit? (EF 70-200mm f/4L USM)

[TucsonTRD]

What minimum focus setting did you have the lens set at? 1.3m or 3m. That could have affected your shots in the 10ft range.


Focus and recompose is not a very good technique either. Even in one shot mode. I don't know your camera at all, so I can't speculate on the settings you may have been using and what you have available.


I was under the impression that all refurbished lenses are tested prior to being resold. In theory, I would imagine they should be more reliable than brand new lenses. I have the 70-200 f4 and I love it. If indeed there is something wrong with the lens, you should send it back and get a replacement as it is a great lens to shoot with.

[TakahiroW4047]

What minimum focus setting did you have the lens set at? 1.3m or 3m. That could have affected your shots in the 10ft range.

I was under the impression that that setting was there to reduce focusing time by allowing the lens to not have to span through the entire focus range?

Focus and recompose is not a very good technique either. Even in one shot mode. I don't know your camera at all, so I can't speculate on the settings you may have been using and what you have available.

The 300D is the very first "Rebel" of the series, and although it still takes great photos to an extent, it only has 7 focus points. So there is always some "focus and recompose" involved since I often times leave the subject in the corners.

The actual size of the AF point is<span>largerthan the box you see in the viewfinder (or in DPP). So, in your example it was integrating the bird and some of the tree branches in the focus calculation.

Most likely my biggest downfall in this situation. 200mm wasn't long enough to have only the subject fill the AF point. Took some photos of my friends playing Tennis earlier this week and they were very good. I now just need a better AI Servo and Spot AF [:P]

[neuroanatomist]

What minimum focus setting did you have the lens set at? 1.3m or 3m. That could have affected your shots in the 10ft range.

I was under the impression that that setting was there to reduce focusing time by allowing the lens to not have to span through the entire focus range?

Correct - the focus limiter just limits the distances through which the AF system will attempt to achieve focus. With the limiter at the longer distance, you simply could not achieve autofocus close than that (meaning an OOF shot in AI-Servo mode with release priority, for example, but I don't think that's an option on a 300D).


RE focus and recompose, you're still probably better off using the closest AF point to the subject that you can, given your desired composition, to minimize the amount of movement you need to make during recomposition.

[TakahiroW4047]

What minimum focus setting did you have the lens set at? 1.3m or 3m. That could have affected your shots in the 10ft range.

I was under the impression that that setting was there to reduce focusing time by allowing the lens to not have to span through the entire focus range?

Focus and recompose is not a very good technique either. Even in one shot mode. I don't know your camera at all, so I can't speculate on the settings you may have been using and what you have available.

The 300D is the very first "Rebel" of the series, and although it still takes great photos to an extent, it only has 7 focus points. So there is always some "focus and recompose" involved since I often times leave the subject in the corners.

The actual size of the AF point is<span>largerthan the box you see in the viewfinder (or in DPP). So, in your example it was integrating the bird and some of the tree branches in the focus calculation.

Most likely my biggest downfall in this situation. 200mm wasn't long enough to have only the subject fill the AF point. Took some photos of my friends playing Tennis earlier this week and they were very good. I now just need a better AI Servo and Spot AF [:P]