Reading mode: Light Dark

AI Focus miss-focus sample

Go to last post
... you switch to all focus points (Auto). Does this make a difference when you recompose? Were all 3 examples you posted using the center focus point only? Just curious to see if the results would be the same if using all points.

Travis
 
It has to be a movement under the active focus point(s) for AI-focus to switch modes. It doesn't matter how the focus point was selected.

Yes, I've been testing it... :-)

David
Travis said:
... you switch to all focus points (Auto). Does this make a
difference when you recompose? Were all 3 examples you posted
using the center focus point only? Just curious to see if the
results would be the same if using all points.

Travis
Click to expand...
 
Or stop down a little and increase the DOF if you've got the light? - m²
Travis said:
... you switch to all focus points (Auto). Does this make a
difference when you recompose? Were all 3 examples you posted
using the center focus point only? Just curious to see if the
results would be the same if using all points.

Travis
Click to expand...
 
All three samples were with only the center focus point enabled. When it stops raining I will try it with the seven focus points.

Frank B
Travis said:
... you switch to all focus points (Auto). Does this make a
difference when you recompose? Were all 3 examples you posted
using the center focus point only? Just curious to see if the
results would be the same if using all points.

Travis
Click to expand...
 
If I increase DOF enough it won't matter if it switches to servo if the new focus point is within DOf, as all will be in focus.

Frank B
Mark Marshall said:
  • m²
Travis said:
... you switch to all focus points (Auto). Does this make a
difference when you recompose? Were all 3 examples you posted
using the center focus point only? Just curious to see if the
results would be the same if using all points.

Travis
Click to expand...
Click to expand...
 
it was explained long time ago in the famous lumious landscape!
(dont know if the name of that mag .is spellled correct!)

the guy that tested 10D found that not only did moving subject activate the autofocus to start tracking a moving object,but the photograpers OWN movement of the camera!!!!

this is very logical that the movement could be in the outsite world,but also the movement of the camera could then activate ai servo,in other words the camara sensor experinces a fixed thing as moving if the camara is moved!
peter
Frank B said:
Frank B
Travis said:
... you switch to all focus points (Auto). Does this make a
difference when you recompose? Were all 3 examples you posted
using the center focus point only? Just curious to see if the
results would be the same if using all points.

Travis
Click to expand...
Click to expand...
 
That would be great, if Frank says he was moving. LOL.

If rather small movements (relative to DOF) on the photographer's part are going to cause this issue to raise its ugly head, I think there will be a LOT of disappointed 300D users.
peter frederiksen said:
it was explained long time ago in the famous lumious landscape!
(dont know if the name of that mag .is spellled correct!)
the guy that tested 10D found that not only did moving subject
activate the autofocus to start tracking a moving object,but the
photograpers OWN movement of the camera!!!!
this is very logical that the movement could be in the outsite
world,but also the movement of the camera could then activate ai
servo,in other words the camara sensor experinces a fixed thing as
moving if the camara is moved!
Click to expand...
--
The Lowest Paid Concert Photographer Around
http://www.neonlightsimaging.com/artshow/final.htm
Photography -- just another word for compromise

'Since we can't keep crime in check, why don't we legalize it and tax it out of business?' -- Will Rogers
 
Actually, from what I'm looking at this very minute, the EXIF data does in fact report whether or not the camera uses AI Servo. Otherwise, at least in my current samples, it simply says AI Focus. Now, I'm assuming that this means that it chose One Shot in those cases, but where the subject was specifically moving towards the camera it did in fact specify AI Servo.

You need a good EXIF reader that exposes the Maker Notes.

I think this is the only definitive way to determine which method the camera ACTUALLY chose.
Frank B said:
I used a 28-135IS with IS shut off. I could here the servo start
to work and see the refocusing. I don't think the EXIF will show a
switch only that the focus mode was AI Focus.
Click to expand...
--

Ulysses
 
Just my thoughts here, but there are lots of issues with the way that the tests are currently being done.

That said, I'd wait for the extensive review(s) to be released from those who are actually using the Digital Rebel in hand.
DavidP said:
That would be great, if Frank says he was moving. LOL.

If rather small movements (relative to DOF) on the photographer's
part are going to cause this issue to raise its ugly head, I think
there will be a LOT of disappointed 300D users.
Click to expand...
--

Ulysses
 
im searching for the article right now on my pc

the guy that experienced this was not the guy that did the technical test at lum.landscape,but a guy that had the 10D out for a day in the nature to test its "real life" performance
yes a movement i DOF can cause servo mode to kick in according to this guy
ill be back with the link in short time!
peter
DavidP said:
If rather small movements (relative to DOF) on the photographer's
part are going to cause this issue to raise its ugly head, I think
there will be a LOT of disappointed 300D users.
peter frederiksen said:
it was explained long time ago in the famous lumious landscape!
(dont know if the name of that mag .is spellled correct!)
the guy that tested 10D found that not only did moving subject
activate the autofocus to start tracking a moving object,but the
photograpers OWN movement of the camera!!!!
this is very logical that the movement could be in the outsite
world,but also the movement of the camera could then activate ai
servo,in other words the camara sensor experinces a fixed thing as
moving if the camara is moved!
Click to expand...
--
The Lowest Paid Concert Photographer Around
http://www.neonlightsimaging.com/artshow/final.htm
Photography -- just another word for compromise

'Since we can't keep crime in check, why don't we legalize it and
tax it out of business?' -- Will Rogers
Click to expand...
 
There are only a handful of people testing these things for reviews. IF this happens to be an actual camera defect causing this in Frank's camera (and others), then the reviewers would likely never see it. I'm sure these cameras have been gone over with a fine-toothed comb.

Even if it's not an issue of a defective camera, but an issue of "it happens sometimes if the conditions are right", that's not a lot of people to be testing for all the different conditions.

What would be most instructive would be to get people like Frank together with people like those who showed the images without problems, and let them all shoot together in both situations. That would say a lot about whether it's camera, photographer, or the particular situation.

Alas, that will never happen.
Ulysses said:
That said, I'd wait for the extensive review(s) to be released from
those who are actually using the Digital Rebel in hand.
Click to expand...
--
The Lowest Paid Concert Photographer Around
http://www.neonlightsimaging.com/artshow/final.htm
Photography -- just another word for compromise

'Since we can't keep crime in check, why don't we legalize it and tax it out of business?' -- Will Rogers
 
heres what the guys says and the link just below:

But, all is not perfect with this new mode called AI Focus. The idea is that when the subject is stationary the focusing mode acts the same as One Shot. Focus the camera on a stationary subject and it locks on. When the subject starts to move (such as a bird taking off) it changes to AI Servo mode and starts focus tracking. Great. But, it isn't that simple. Three days of testing with a 400mm lens at a wildlife reserve in south-central Florida showed me that the camera auto-switches to AI Focus when the camera is moved, not just the subject, and it doesn't switch back readily. A nice first attempt at a solution, but by no means ideally executed.

the link: http://luminous-landscape.com/reviews/cameras/10d.shtml
peter
peter frederiksen said:
DavidP said:
If rather small movements (relative to DOF) on the photographer's
part are going to cause this issue to raise its ugly head, I think
there will be a LOT of disappointed 300D users.
peter frederiksen said:
it was explained long time ago in the famous lumious landscape!
(dont know if the name of that mag .is spellled correct!)
the guy that tested 10D found that not only did moving subject
activate the autofocus to start tracking a moving object,but the
photograpers OWN movement of the camera!!!!
this is very logical that the movement could be in the outsite
world,but also the movement of the camera could then activate ai
servo,in other words the camara sensor experinces a fixed thing as
moving if the camara is moved!
Click to expand...
--
The Lowest Paid Concert Photographer Around
http://www.neonlightsimaging.com/artshow/final.htm
Photography -- just another word for compromise

'Since we can't keep crime in check, why don't we legalize it and
tax it out of business?' -- Will Rogers
Click to expand...
Click to expand...
 
DavidP said:
What would be most instructive would be to get people like Frank
together with people like those who showed the images without
problems, and let them all shoot together in both situations.
Click to expand...
Heheheh... THAT'S not gonna happen. :-)
DavidP #28649 said:
That would say a lot about whether it's camera, photographer, or
the particular situation.

Alas, that will never happen.
Click to expand...
Oh... you already covered that. :-)

Heheheh... Anyway, while it's all academically interesting, I don't anticipate it to be a serious joy-killer.

This is just like when with the old prosumer F505V camera, we had a problem called BOCS (Blue Over Correction Syndrome) where the camera in certain situations would make flash shots look horribly under-saturated and bluish. Well, it was a bonafide issue, but we actually MAGNIFIED the problem in our own minds due to the fact that ALL we were doing was shooting flash shots in precisely the situations that generated the problem. We were exaggerating the issue, though it was a real one.

Patient: Doctor, it hurts when I do this!
Doctor: Well, don't do that!

hahahahahahahah... I don't expect it to be even that bad.

--

Ulysses
 
You have to move quite a bit...
DavidP said:
If rather small movements (relative to DOF) on the photographer's
part are going to cause this issue to raise its ugly head, I think
there will be a LOT of disappointed 300D users.
peter frederiksen said:
it was explained long time ago in the famous lumious landscape!
(dont know if the name of that mag .is spellled correct!)
the guy that tested 10D found that not only did moving subject
activate the autofocus to start tracking a moving object,but the
photograpers OWN movement of the camera!!!!
this is very logical that the movement could be in the outsite
world,but also the movement of the camera could then activate ai
servo,in other words the camara sensor experinces a fixed thing as
moving if the camara is moved!
Click to expand...
--
The Lowest Paid Concert Photographer Around
http://www.neonlightsimaging.com/artshow/final.htm
Photography -- just another word for compromise

'Since we can't keep crime in check, why don't we legalize it and
tax it out of business?' -- Will Rogers
Click to expand...
--
Phil Askey
Editor / Owner, dpreview.com
 
an Elan film cam will do better in action shooting. Test it in many action settings and the flaws will come out of not being able to manually control the Autofocus.

Agree that the DR will be better than digicams in AF and low noise and action shooting, but it is no Elan/10d that has CF4,1 AISERVO where one can use the * and be in AISERVO all the time.

Make the comparisons to film capability please. Folks need to understand the limitations of what they are spending their digital money on. Too many have thought in the past their digicams could do action shooting better than a Elan....becasue they spent more......and the reviews didn't talk about it.......not the case.

MAC
Phil Askey said:
peter frederiksen said:
Frank B said:
Frank B
Travis said:
... you switch to all focus points (Auto). Does this make a
difference when you recompose? Were all 3 examples you posted
using the center focus point only? Just curious to see if the
results would be the same if using all points.

Travis
Click to expand...
Click to expand...
Click to expand...
--
Phil Askey
Editor / Owner, dpreview.com
Click to expand...
--
MAC
http://www.digi-pictures.com
 
Ulysses said:
This is just like when with the old prosumer F505V camera, we had a
problem called BOCS (Blue Over Correction Syndrome) where the
camera in certain situations would make flash shots look horribly
under-saturated and bluish. Well, it was a bonafide issue, but we
actually MAGNIFIED the problem in our own minds due to the fact
that ALL we were doing was shooting flash shots in precisely the
situations that generated the problem. We were exaggerating the
issue, though it was a real one.
Click to expand...
If I recall correctly (maybe not) didn't this BFS (I know it was called something else as well but maybe it's an unrelated issue) problem persist into the F717 as well (Brian Siverly rings a bell) until a firmware fix?
Member said:
Patient: Doctor, it hurts when I do this!
Doctor: Well, don't do that!
Click to expand...
What? Pay the bill?? heheheh
Member said:
hahahahahahahah... I don't expect it to be even that bad.

--

Ulysses
Click to expand...
 
So do you have any explanations for why Frank's seeing what he's seeing?

Especially when somebody else a day or two ago (wish I had the link handy) showed similar tests where the camera didn't choose to re-focus.

The one thing that comes to mind is the possibility that Frank let off enough pressure on the shutter button and then re-pressed it, so that the camera re-focused. I've certainly seen some finicky shutter releases that might allow for that possibility to occur without one knowing it.
Phil Askey said:
You have to move quite a bit...
Click to expand...
--
The Lowest Paid Concert Photographer Around
http://www.neonlightsimaging.com/artshow/final.htm
Photography -- just another word for compromise

'Since we can't keep crime in check, why don't we legalize it and tax it out of business?' -- Will Rogers
 
You must log in or register to reply here.

Keyboard shortcuts

f
Forum
m
My threads
Mobile site
About
Editorial content
Cameras & Lenses
Community
All content, design, and layout are Copyright © 1998–2025 Digital Photography Review All Rights Reserved.
Reproduction in whole or part in any form or medium without specific written permission is prohibited.
When you use DPReview links to buy products, the site may earn a commission.
©GPS Media - Guides, Products, Services.
Back
Top