Canon 70-200mm F4L Users advice needed

[Canew]

Camera elevation at around 1.4M, level with the help of the level gauge.
Place the subject about 1.3M away from the camera, make sure subject is parallel to the lens, set focal length to 100mm, focus on the no. 4 of f/4L USM print (adjust column height if neccessary), pan your camera to focus on far object, pan back to subject's focus point, set lens focus mode to manual, set exposure and take your shots.

Roberteo, some questions for clarification:
1. Is the camera elevation important?
2. "pan your camera to focus on far object, pan back to subject's focus point" - use AF. Correct?
3. "set lens focus mode to manual, set exposure and take your shots" - use MF after getting a focus lock in AF in step 2 above?

Maybe will do it this weekend.

 

[madmacs]

Roberteo, the link seems to be down.

try again. i can access it.

 

[Canew]

Ya, I can access it now already. (will remove the message thread)

 

[Roberteo]

Canew

1) Elevation is not important. Just to provide as much information as possible.

2) Using AF to focus, that is the purpose of this test.

3) Switch to MF after AF to prevent any refocus of the subsequent shots.

Hope to see your post soon. Thx

Still no time to try out the second method, sorry, will post result as soon as I have done the test.

 

[sequitur]

by the way,


you can't have perfect focus from the range 70-200 - this is because there is a need for the focusing element to accomodate to the 70-200 range...


for my old 70-200 it backfocused at one end and was perfect at the other... so end up the calibration done was to make it not perfect at both ends, but within tolerance.


this kind of thing really give and take. unless you have a prime (like 35/1.4, 24/1.4, 85/1.2) then they can calibrate it to perfectly spot on focus for you.

 

[Canew]

Canew

1) Elevation is not important. Just to provide as much information as possible.

2) Using AF to focus, that is the purpose of this test.

3) Switch to MF after AF to prevent any refocus of the subsequent shots.

Hope to see your post soon. Thx

Still no time to try out the second method, sorry, will post result as soon as I have done the test.

OK. Got yor message. Hope to do my test soon too...

 

[Canew]

Hi everyone (especially to Roberteo), here are the shots that I have done per Roberteo's instructions. My settings are:

ISO 100.
Quality = JPEG - L compression.
AF mode = One Shot.
Metering = Center Weighted.
Mirror Lockup = Disabled.
Shot taken with timer.

 

[Canew]

For a real life performance of my copy of the 70-200 mm f/4 L lens, please visit this thread.