October 23, 2014, 04:19:22 PM

Author Topic: 5D Mark iii ai-servo  (Read 7844 times)

DigiDen

  • Guest
5D Mark iii ai-servo
« on: January 07, 2013, 03:01:31 AM »
I have 5d mark 3 and 70-200/2.8 ii lense.

Sunny day I tried to make shots runing dogs.

I tried to use ai-servo, case1 and case6, zone af points and one af point with ext, but everytime i have 50% shots with missing focus.

What i do wrong ?


http://img26.imageshack.us/img26/2241/test1tff.jpg
http://img547.imageshack.us/img547/9121/test2p.jpg
http://img6.imageshack.us/img6/7719/test3xr.jpg
« Last Edit: January 07, 2013, 09:43:56 AM by DigiDen »

canon rumors FORUM

5D Mark iii ai-servo
« on: January 07, 2013, 03:01:31 AM »

Eli

  • Rebel T5i
  • ****
  • Posts: 148
    • View Profile
    • http://500px.com/elindaire
Re: 5D Mark iii ai-servo
« Reply #1 on: January 07, 2013, 03:55:07 AM »
What was your shutter speed?

DigiDen

  • Guest
Re: 5D Mark iii ai-servo
« Reply #2 on: January 07, 2013, 04:16:01 AM »
Tv and M mode with 1/1600 - 1/2000
« Last Edit: January 07, 2013, 04:23:07 AM by DigiDen »

petrosv

  • Power Shot G7X
  • **
  • Posts: 18
    • View Profile
Re: 5D Mark iii ai-servo
« Reply #3 on: January 07, 2013, 06:16:03 AM »
It's different missing focus  from blurry images cause tv(speed) .For a reason  ai servo in 5diii or in 7d  not work  well in very fast situations , as well as servo focus."Reload" and  shoot again ,you wil see that you will have a lot of pin sharp images. Sorry for my very bad English .

DigiDen

  • Guest
Re: 5D Mark iii ai-servo
« Reply #4 on: January 07, 2013, 08:45:49 AM »
but if
1. ai servo in 5diii not work well in very fast situations
2. af in 5diii is better than in 1dm iv
3. af in 5diii is the same as in 1dx

so what camera I need to use for very fast situations?

petrosv

  • Power Shot G7X
  • **
  • Posts: 18
    • View Profile
Re: 5D Mark iii ai-servo
« Reply #5 on: January 07, 2013, 09:09:20 AM »
You can use perfectly 5d3 in original servo focus .

DigiDen

  • Guest
« Last Edit: January 07, 2013, 09:35:23 AM by DigiDen »

canon rumors FORUM

Re: 5D Mark iii ai-servo
« Reply #6 on: January 07, 2013, 09:33:39 AM »

96Brigadier

  • PowerShot G1 X II
  • ***
  • Posts: 39
    • View Profile
Re: 5D Mark iii ai-servo
« Reply #7 on: January 07, 2013, 09:47:09 AM »
Check your AI Servo Priority setting.  Looks like you could have it set to Release/Speed Priority rather than Focus Priority or Equal Priority.

Explanation here:

http://learn.usa.canon.com/resources/articles/2011/1dx_af_config_article.htmlp

AI Servo 1st image priority:
When starting to follow-focus a moving subject with AI Servo AF, if the user fully presses down on the shutter button immediately after starting to focus, what will the camera do?

Equal Priority: Camera allows a bit of time before firing first shot in a sequence, to give AF system a bit of "cushion" to focus completely on subject. This setting is new on EOS cameras.

Release Priority: Camera gives "priority" to releasing shutter – camera will fire virtually instantly, even if AF system hasn't fully locked-on to subject. News and wire-service shooters, who often are more concerned with the "decisive moment" than absolute tack-sharp images, may prefer this setting.

Focus Priority: Camera gives "priority" to assuring sharp focus – when trying to focus and shoot quickly, shutter release may be delayed for a perceptible moment while AF system confirms that first shot will be sharp.

AI Servo 2nd image priority:
This concerns what happens when the user tries to shoot a sequence of two or more continuous pictures of a moving subject with AI Servo AF. For the 2nd and all subsequent shots in that sequence, does the camera try to shoot as fast as it possibly can – even if this means a few frames may not be tack-sharp – or will it slow down the fps rate as needed to allow the AF system to confirm that virtually all frames in a sequence are as sharp as they can be?

Equal Priority: The EOS-1D X and 5D Mark III give equal priority to maintaining fps shooting speed, while allowing time for AF. In extremely dim conditions or with very difficult-to-focus subjects, shooting speed may slow down.

Speed Priority: Camera gives priority to maintaining fps shooting speed, even if it means the AF system may not have fully confirmed sharp focus for every frame in a sequence. Again, for example, capturing the moment may be more important for a traditional news shooter than having each and every frame tack-sharp in a high-speed sequence.

Focus Priority: During continuous shooting with focus-tracking in AI Servo AF, the camera gives priority to assuring sharpest possible focus for all frames in a sequence, and will readily slow-down the fps rate if necessary to allow this.

some samples

http://img26.imageshack.us/img26/2241/test1tff.jpg
http://img547.imageshack.us/img547/9121/test2p.jpg
http://img6.imageshack.us/img6/7719/test3xr.jpg
« Last Edit: January 07, 2013, 09:50:13 AM by 96Brigadier »


DigiDen

  • Guest
Re: 5D Mark iii ai-servo
« Reply #9 on: January 07, 2013, 09:50:19 AM »
mdf is 1.2m, here the distance is much greater

Dylan777

  • Canon EF 400mm f/2.8L IS II
  • *******
  • Posts: 4194
    • View Profile
Re: 5D Mark iii ai-servo
« Reply #10 on: January 07, 2013, 09:52:02 AM »
My fav AI servo is case2 with 4pts AF expansion mode.

Shooting info: Tv, 1/800
http://albums.phanfare.com/isolated/zI4RaRdU/1/5903066

Body: 1DX -- 5D III
Zoom: 16-35L f4 IS -- 24-70L II -- 70-200L f2.8 IS II
Prime: 40mm -- 85L II -- 135L -- 200L f2 IS -- 400L f2.8 IS II

DigiDen

  • Guest
Re: 5D Mark iii ai-servo
« Reply #11 on: January 07, 2013, 09:54:02 AM »
Check your AI Servo Priority setting.  Looks like you could have it set to Release/Speed Priority rather than Focus Priority or Equal Priority.


I tried
defalult for both (Release Priority and Speed Priority), Focus priority for both, Release Priority and Focus Priority

DigiDen

  • Guest
Re: 5D Mark iii ai-servo
« Reply #12 on: January 07, 2013, 09:59:00 AM »
My fav AI servo is case2 with 4pts AF expansion mode.

Shooting info: Tv, 1/800
http://albums.phanfare.com/isolated/zI4RaRdU/1/5903066

in this samples you have large DOF, but on the tele + f/2.8 dof is very small
« Last Edit: January 07, 2013, 10:01:10 AM by DigiDen »

canon rumors FORUM

Re: 5D Mark iii ai-servo
« Reply #12 on: January 07, 2013, 09:59:00 AM »

East Wind Photography

  • 5D Mark III
  • ******
  • Posts: 713
  • EWP
    • View Profile
Re: 5D Mark iii ai-servo
« Reply #13 on: January 07, 2013, 10:59:45 AM »
So first of all servo AF is not always 100% no matter how you have your settings.  This is true on any camera.  The goal is to increase your keep rate.  You will always have AF failures. To compensate for AF inaccuracies, use a smaller aperture which will mask some of the problem and increase your hit rate.

5DIII has very low noise level so in good lighting you can use ISO 1000 or higher and F/7.1 or even F/8.  I wouldnt go higher than F/8 though.  The increased DOF at F8 will increase your keeper rate.  I use that with shooting birds in flight.  I still only get 50% to 75% keeper rate but of those, the focus is tack sharp.  Take lots of pictures to increase the % of keeper shots.

I typically shoot 400-500 shots in a couple of hours and end up keeping only a hand full of shots.  It's all in the numbers.  Keep at it and you will find the right mix of settings.

The lens and camera are both top of the line.  Most of the issues people have are from not having the camera set up right for the purpose they are shooting.  5DIII is a complex pro level camera and to make best use of the AF, you need to have it set up correctly.  It's not like one of the older models that have to do pretty good in all situations.  The new system lets you adjust so it can perform better in specific purposes.

East Wind Photography

  • 5D Mark III
  • ******
  • Posts: 713
  • EWP
    • View Profile
Re: 5D Mark iii ai-servo
« Reply #14 on: January 07, 2013, 11:02:18 AM »
Forgot to add that I use case 2 mostly and center point only in most action shots.  Sometimes use spot focus if the background is not smooth.  I can use all focus points if I'm shooting against a plain sky or have a very large subject that is high contrast...say the head of a bald eagle when it's pretty close to me.  Otherwise I use center focus point or spot focus.

canon rumors FORUM

Re: 5D Mark iii ai-servo
« Reply #14 on: January 07, 2013, 11:02:18 AM »