LOG IN    OR   REGISTER TO FORUMS


AI Focus VS. AI Servo

FORUMS Canon Cameras, Lenses & Accessories Canon EOS Digital Cameras
Thread started 05 Sep 2009 (Saturday) 16:29   
LIST NEARBY THREADS
 
texshooter
Senior Member
Joined Jun 2009
404 posts
[MORE/SHARE]

AI Focus and AI Servo seem like the same thing to me.

AI Focus is suppose to continuously change focus if your subject is moving, but AI Servo only changes focus if "you anticipate the subject moving."

Uhh?

Either the subject is moving or it isn't. So why would I use one focus setting instead of the other?

To make things more confusing, the 5D Mark ii has a custom function "C.Fn III-7 AF Point area expansion" that is suppose to expand the focusing area when you are on the AI Servo focus mode. Isn't that the same thing as selecting all focus nodes with that button on the front top right of the camera with the square puzzle icon? Why use C.Fn II-7. I'm sure I'm missing something.

Post #1, Sep 05, 2009 16:29:50




LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as registered member)
Jezza8
Mostly Lurking
Joined Jan 2009
19 posts
UK - Surrey
[MORE/SHARE]

AI Servo is effectively the mode you use if you know you want to track a moving subject, simple and straightforward.

AI Focus is supposed to be more intelligent, it works out if the subject is moving or not, if not it will fix the focus on the point it initially locks on and not move (One shot mode) otherwise it will switch to tracking mode like AI Servo. In theory this should give you the best of both worlds, in practice it is a bit of a dogs dinner and you are never quite sure which mode you are in, so my advice is to forget AI Focus and use either One Shot or AI Servo.

Post #2, Sep 05, 2009 17:20:07




LOG IN TO REPLY
artyman
Cream of the Crop
artyman's Avatar
Joined Feb 2009
14,294 posts
Hampshire UK
[MORE/SHARE]

I have my camera set to AI Servo allocated to the * button, one press and you have one shot , just hold for servo :)

Post #3, Sep 05, 2009 17:22:58


Art that takes you there. http://www.artyman.co.​ukexternal link
Ken
Canon 7D, 350D, 15-85, 18-55, 75-300, Cosina 100 Macro, Sigma 120-300

LOG IN TO REPLY
texshooter
THREAD ­ STARTER
Senior Member
Joined Jun 2009
404 posts
[MORE/SHARE]

Fact 1: AI Focus mode locks the focus when the subject is still.
Fact 2: AI Focus mode unlocks the focus when the subject moves

Fact 3: AI Servo mode keeps the focus still when the subject is still.
Fact 4: AI Servo mode moves the focus when the subject moves

If I have my facts straight, the only difference between fact 1 and 2 is that AI servo mode technically does not "lock" the focus when the subject remains still. Instead, it only keeps the focus "still."

I may be splitting hairs, but I don't see any difference between "locking" the focus and "keeping it still." I still don't see any meaningful distinction between AI Focus and AI Servo modes, unless.....

There is a time delay when the focus control goes from the locked position to the unlocked position. If that's the case, then AI Servo mode will have a practical advantage for really quick shooting.

Post #4, Sep 05, 2009 17:34:44 as a reply to Jezza8's post 14 minutes earlier.




LOG IN TO REPLY
buddy4344
Senior Member
Joined Nov 2006
924 posts
Allentown, PA
[MORE/SHARE]

i have always wondered the same, though I mostly use Servo if I expect movement. I also wonder about single point focus vs. matrix of points when shooting moving subjects.

Post #5, Sep 05, 2009 17:37:45


Buddy4344

Gear: Canon 5D MkIII, 7D, 30D, 300D, Canon Lenses: 100 macro, 100-400L IS, 24-105L IS, 400DO IS, 500L IS. Kenko extension tubes, Kenko 1.4x pro TCon.and Kiboko 30L and 22L+

LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as registered member)
ed ­ rader
"I am not the final word"
ed rader's Avatar
Joined May 2005
22,036 posts
silicon valley
[MORE/SHARE]

buddy4344 wrote in post #8590393external link
i have always wondered the same, though I mostly use Servo if I expect movement. I also wonder about single point focus vs. matrix of points when shooting moving subjects.

i suppose it depends on style and what you are shooting. i always use a single point and never focus/recompose.

ed rader

Post #6, Sep 05, 2009 17:40:00


http://instagram.com/e​draderphotography/external link
http://erader.zenfolio​.com/external link
5D3, SL1, 16-35L f4 IS, 24-70L II, 70-300L, 100-400L, 35f2 IS, 24mm f2.8 ef-s, 15mm FE (sigma), 270ex II, gitzo, markins, benro

LOG IN TO REPLY
texshooter
THREAD ­ STARTER
Senior Member
Joined Jun 2009
404 posts
[MORE/SHARE]

A still small voice in the back of my mind tells me there must have been a reason why Canon added the AI Focus mode. I just can't figure out when it is better to shoot AI Focus over AI Servo.

Post #7, Sep 05, 2009 17:43:02 as a reply to ed rader's post 3 minutes earlier.




LOG IN TO REPLY
Mark_Cohran
Cream of the Crop
Mark_Cohran's Avatar
Joined Jul 2002
15,545 posts
Portland, Oregon
[MORE/SHARE]

It's been my experience that AI Focus isn't as intelligent as Canon would like you to think. If I need AI Servo, then I use AI Servo, otherwise, I use One Shot.

Post #8, Sep 05, 2009 17:43:34


Mark
-----
Some primes, some zooms, some Ls, some bodies and they all play nice together.
Thirty-five years of shooting and still learning.
My G&N Blogexternal link (NSFW)- My Complete Gear Listexternal link - Mac-Photo Websiteexternal link - My Tumblr Siteexternal link (NSFW)
G&N FORUM EARLY ACCESS & IMAGE POSTING RULES

LOG IN TO REPLY
texshooter
THREAD ­ STARTER
Senior Member
Joined Jun 2009
404 posts
[MORE/SHARE]

I figured it out. You want to use the AI Focus mode when you plan to shoot in situations where you wan't to switch back and forth from On Shot mode to AI Servo mode without having to turn dials on the camera.

Post #9, Sep 05, 2009 17:55:37 as a reply to Mark_Cohran's post 12 minutes earlier.




LOG IN TO REPLY
artyman
Cream of the Crop
artyman's Avatar
Joined Feb 2009
14,294 posts
Hampshire UK
[MORE/SHARE]

texshooter wrote in post #8590460external link
I figured it out. You want to use the AI Focus mode when you plan to shoot in situations where you wan't to switch back and forth from On Shot mode to AI Servo mode without having to turn dials on the camera.

That is effectively what I said I do with allocatiing focus to my * button.

Post #10, Sep 05, 2009 18:00:11


Art that takes you there. http://www.artyman.co.​ukexternal link
Ken
Canon 7D, 350D, 15-85, 18-55, 75-300, Cosina 100 Macro, Sigma 120-300

LOG IN TO REPLY
Owhat
Member
Joined Jan 2011
84 posts
West Los Angeles, CA. USA
[MORE/SHARE]

Interesting.

Post #11, Jun 23, 2011 14:52:19


flickrexternal link
5D Mark III | 5D Mark II | Rokinon 14 2.8 | 35 1.4L | 85 1.2L II | 100 2.8L macro IS | 135 2L | 200 2.8L | 580EX II | 430EX II

LOG IN TO REPLY
sponsored links
(this ad will go away when you log in as registered member)
kf095
Cream of the Crop
kf095's Avatar
Joined Dec 2009
5,594 posts
Canada, Ontario, Milton
[MORE/SHARE]

I like AI Focus for pictures like this.

IMAGE: https://lh4.googleusercontent.com/-KAeuqcS-HjM/TfV4ur-Am1I/AAAAAAAAUqI/ODyOb-Fd4L8/s800/_MG_7873.jpg

IMAGE: https://lh6.googleusercontent.com/-9I2rO42ZNbk/TfV4wabrRTI/AAAAAAAAUqQ/koyj2e4PRZ8/s800/_MG_7877.jpg


I'll have all AF points enabled and camera will lock to the object almost always.
Once focus is locked, it will red-light selected focus point(s).
It allows me to take quick snapshots, without selecting focusing point, camera does it for me and if objects moves, but not a lot, it is tracking it.

IMAGE: https://lh6.googleusercontent.com/-fNUtJI6jOuo/TfTIOzFWarI/AAAAAAAAUh4/aQULVniES_E/s800/_MG_7359.jpg

IMAGE: https://lh6.googleusercontent.com/-yhcy7qQFRDg/TfTIPnJPQzI/AAAAAAAAUh8/_xKucj1teDo/s800/_MG_7365.jpg


If I have all AF points enabled on AI Servo camera is focusing, but no red-lights on AF points once it is locked.
I use AI Servo for fast moving objects with single AF point. At this case it is showing red-light square for AF once it is locked.

IMAGE: https://lh3.googleusercontent.com/-CGQpB6MlUvg/TLMvjhDN6FI/AAAAAAAAOIM/_bZLboiOB_s/s720/2010_10_11_8824.JPG

And my focus button is on *, of course.

Post #12, Jun 23, 2011 15:47:33


Siteexternal link. Flickrexternal link. DigitaL and AnaLog Gear.

LOG IN TO REPLY
Snydremark
Cream of the Crop
Joined Mar 2009
15,639 posts
Issaquah, WA USA
[MORE/SHARE]

texshooter wrote in post #8590414external link
A still small voice in the back of my mind tells me there must have been a reason why Canon added the AI Focus mode. I just can't figure out when it is better to shoot AI Focus over AI Servo.

Pretty much never. AI Focus is a "smart" mode that is really poor at what it does. I suggest forgetting the setting is even there and use either One Shot if you know your subject is going to be still, or Servo if you know it may move.

Post #13, Jun 23, 2011 15:51:38


- Eric S.: My Birds/Wildlifeexternal link (7D MkII, 7D, 40D, Canon 10-22 f/3.5-4.5, Canon 24-105L f/4 IS, Canon 70-200L f/2.8 IS MkII, Canon 100-400L f/4.5-5.6 IS, Canon 100mm f/2.8 Macro, Tamron 18-270 DiII PZD, 580EX II)
"The easiest way to improve your photos is to adjust the loose nut between the shutter release and the ground."

LOG IN TO REPLY
fotocrack
Senior Member
Joined Apr 2010
193 posts
Orange County, CA
[MORE/SHARE]

Snydremark wrote in post #12646361external link
Pretty much never. AI Focus is a "smart" mode that is really poor at what it does. I suggest forgetting the setting is even there and use either One Shot if you know your subject is going to be still, or Servo if you know it may move.

Do you have any pictures in the different modes? I have a 7D too and I have been using it pretty much have it on One shot all the time. Would try out the other and see what the difference would be. What would be the best way to test this?

Post #14, Jun 23, 2011 16:38:16


5DM3 lover :cool: //My custom build computer //My Feedback
PLEASE DONATE TO YOUR LOCAL FOOD BANKS AND LOCAL CHARITIES

LOG IN TO REPLY
EL_PIC
Goldmember
EL_PIC's Avatar
Joined Dec 2009
2,028 posts
Austin Texas - Lucca Italy
[MORE/SHARE]
banned

Mark_Cohran wrote in post #8590416external link
It's been my experience that AI Focus isn't as intelligent as Canon would like you to think. If I need AI Servo, then I use AI Servo, otherwise, I use One Shot.

AI = Artifical Intelligence.
I think a photographer needs Natural Intelligence more that AI.
Same for Military Intelligence !

Post #15, Jun 23, 2011 16:51:05


EL_PIC - RIT BS Photo '78 - Photomask Engineering Mgr
Canon DSLR - Nikon SLR - Phase One 60MP MFDSLR
http://www.Photo-Image-Creations.comexternal link
http://www.musecube.co​m/el_pic/external link
http://www.facebook.co​m/PhotoImageCreationsexternal link

LOG IN TO REPLY


LIST NEARBY THREADS
64,550 views & 0 likes for this thread
AI Focus VS. AI Servo
FORUMS Canon Cameras, Lenses & Accessories Canon EOS Digital Cameras



NOT A MEMBER YET? CLICK HERE TO REGISTER TO FORUMS

CHANGE BODY TEXT SIZE FOR ALL THREAD PAGES
POWERED BY AMASS 1.0version 1.0
made in Finland
by Pekka Saarinen
for photography-on-the.net


SEND FEEDBACK TO STAFF  |  JUMP TO FORUM...  |  FORUM RULES


Spent 0.00083 for 4 database queries.
PAGE COMPLETED IN 0.02s
1039 guests, 828 members online
Simultaneous users record so far is 3341, that happened on Dec 11, 2014
Latest registered member is Lidas

COOKIES DISCLAIMER: By using this site you agree that some cookies will be stored on your browser. For unlogged users we store one session id cookie. For registered members we store (in addition to login session cookie) only cookies that are essential for required functionality, we do not store any personal tracking data in cookies or other browser's data storage methods.