2.8 L apeture requirements for auto focus on 1DMk2N

Hi,

Firstly I apologize if this topic has been covered before…I did look and do a search and didn’t really find what I was looking for.

I have a 1DMk2N (recently purchased when Dell went crazy a few months ago). I also had from before the 100-400 4.5-5.6L IS and a 70-200 2.8 L non IS and the 20D.

I shoot almost exclusively sports pictures, which is why I upgraded from the 20 D that I thought was a great camera.

I keep reading about the 2N auto focus and how it needs the 2.8 L aperture to get all of the auto focus points working.

I have to admit my first set of photos with the 2N at our annual December year end closer ski race were not as perfect as I was expecting them to be focus wise. I was using the 100-400. I thought the camera did a worse job focusing than the 20D although I did enjoy the 8.5 fps.

Does anyone have any experience on what to expect auto focus wise between the 100-400 and the 70-200 on the 2N? From what I’ve read you need the 2.8 L aperture to make the auto focus effective on the 2N. Does that mean my 100-400 will not be particularly effective on the new camera?

Obviously I’m a little confused and would appreciate any help the forum members can provide so I can use the camera and lens combination the most effectively.

Thanks in advance for your comments
Mortyski

--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

actually the 1Dmk2N will focus with 1/3 DOF accuracy with an F4.0 (Center point only) or better lens. F 2.8 is for the consumer cameras to work at 1/3 DOF.
--
Cal

Put a Canon to your head, You deserve it....

http://funshots.smugmug.com/

Hi Cal,

Does that mean I have to set the 2N to centre point focus only on the 100-400 lens. Seems like a waste having 45 points and you can only use one.

Thanks for your response
Morty
--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

That's for your cross type sensors (horizontial and vertical), remaing are horizontial. At f/2.8 or wider you have 7 cross type sensors. With certain L series lenses, F4 will give you one cross sensor and 44 horizontial only. Cross sensors are three times more accurate than horizontial type sensors.

mortyski said:

Hi Cal,

Does that mean I have to set the 2N to centre point focus only on
the 100-400 lens. Seems like a waste having 45 points and you can
only use one.

Thanks for your response
Morty
--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

Click to expand...

Hi Brian,

Thanks for the response. So in layman's terms what does all of this mean? How do I set up the camera for sports photography (i.e. action in the center of the picture) with the 100-400 L and the 70-200 L for the best results or does the camera automatically make the adjustments. Do I have both lenses wide open for max aperture and adjust the ISO setting to get a reasonable shutter speed or is there some other trick.

I want to get the best auto focus result that I can. I shoot mainly snow ski races and water skiers.

Thanks again
Morty

--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

The 100-400 L is 4.5 to 5.6, so no cross sensors. If getting "best" focus accuracy, get a 1.4 TC for your 70-200/2.8 L. I have both lenses, and looking at the 1DMk2N replacement if it is FF, or get the 1DsMk2. I want the best accuracy for the Pan Mass Challenge, which means I'm using my 70-200/2.8 L. The lens maximum aperture determines whether you have seven, 1, or no cross sensors.

mortyski said:

Hi Brian,

Thanks for the response. So in layman's terms what does all of
this mean? How do I set up the camera for sports photography (i.e.
action in the center of the picture) with the 100-400 L and the
70-200 L for the best results or does the camera automatically make
the adjustments. Do I have both lenses wide open for max aperture
and adjust the ISO setting to get a reasonable shutter speed or is
there some other trick.

I want to get the best auto focus result that I can. I shoot
mainly snow ski races and water skiers.

Thanks again
Morty

--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

Click to expand...

You don't have to shoot wide open for the cross sensors to activate. Lens is always wide open when focusing, it stops down to the aperture that you select. Make sure you are in the AI servo mode, and select either low speed or high speed continuous shooting.

I wish there was an edit button here. I wanted to say lens will stop down to
the aperture that you select as the camera is getting ready to take a picture.

brianric said:

You don't have to shoot wide open for the cross sensors to
activate. Lens is always wide open when focusing, it stops down to
the aperture that you select. Make sure you are in the AI servo
mode, and select either low speed or high speed continuous shooting.

Click to expand...

Thanks Brian,

What you are saying then is don't expect stellar results with the 100-400 L in autofocus accuracy. I wonder why it worked better with the 20 D than it appears to be working with the 2N

Confused in Calgary
Mortyski
--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

Anybody have anything else to add?

I plan to take a lot of shots on the 100-400 and 70-200 today and will report back my findings
--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

http://www.photoworkshop.com/canon/EOS_Digital.pdf

Check out the settings on page 19.

thanks Anthony,

I will read that article with great interest. I did take a lot of snow skiing shots on the weekend. When I figure what the difference was between the 100-400 and 70-200 re lens focusing qualities I will report my findings

best regards,
Morty

Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

Help...

I read the Canon book suggested above, and modified the custom functions per that book and the Sports Illustrated suggestions for the camera.

Nothing worked…My auto focus this weekend was terrible.

When you assign the auto focus to the * button do you have to keep holding it down while shooting or does the shutter button finally take over in a sequence of shots. I tried both and it didn’t seem to make any difference

How do you tell that a lens is back focusing when there does not appear to be anything focused in the photo.

I also took off my UV filter hoping that was the problem, didn’t help!

So far the 1D Mark 2 N and the 100-400 L have been a terrible combination

Any help will be gratefully received!

Thanks
Morty

--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

First of all no you dont have to turn any AF points off for the aperture of the lens

As someone already explained you simply get more accuracy with faster lenses

if you have a lens/tc combo with a max aperture of F8 you will loos all but the center point automatically

Now for your reasons of OOF images. Obviously we dont have the examples which would help but one possibility is the use of 45 points with snow.

Snow as well as water or grass combined with sun can often give a strong contrast for the AF system to focus on and therfor the focus might be in front of the subject

In cases like this i tend to use center point with 7 point expansion and keep the center point on the subject

if you post some examples we might be able to better pinpoint the issues you are having

--
Michael Salzlechner
http://www.PalmsWestPhoto.com

Hi,

Thank you for your help.

Here a shot taken yesterday as part of a sequence that was all out of focus



best regards,
Morty

--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

try what i mentioned

switch to center point, AI Servo, 7 point expansion

make sure to keep the center point on the subject and make sure to track the subject (dont just mash the button down)

--
Michael Salzlechner
http://www.PalmsWestPhoto.com

oops. see my reply below

one more thing

make sure to use the center point to aquire focus and then keep tacking the subject and try not to loose focus

--
Michael Salzlechner
http://www.PalmsWestPhoto.com

Thanks I will try.

It's frustrating! I made all of the "suggested changes" in my custom functions and the autofocus was worse than the off the shelf settings..and dare I say it, worse than the 20D

Do you think the camera / lens combination is back focusing and needs to be serviced?

--
Canon 1D Mark 2 N
Canon 20 D
Canon S80
Sony HDR-HC3
100-400 F4.5/5.6 L IS
70-200 F2.8L
24-70 F2.8 L
1.4 TC Canon II
580 EX
BG-E2
Custom Bracket QRS-35-EV
and lots and lots of memory cards

mortyski said:

Do you think the camera / lens combination is back focusing and
needs to be serviced?

Click to expand...

Allthough i cant say yes or no the focus in the picture you posted is so far off it couldnt be simple focus adjustment but you can always do a simple test

it looks to me like either the focus was on the background or for some reason or another the focus didnt move with the skier

i am guessing you had it on servo focus and where tracking the skier.

--
Michael Salzlechner
http://www.PalmsWestPhoto.com

The MKIIN, 100-400L works great for me. I use AI servo with all focus points active. The camera will automatically check center focus first, then will track the originally acquired subject wherever it goes in the 45 point range. Works very well almost all the time. Here is a link to some shots I took with this combo . . . .

http://www.pbase.com/jtuell/usc_v_az