Depressed about my new 24-70L

[Ronald S. Jr.]

Well, so I got my 24-70L via UPS today that I purchased from a fellow POTN'er. It's a wonderfully built, perfectly sharp, beautiful lens. However, this evening, an hour and a half ago or so, after I had been testing it out for a while, I decided to do some low light stuff. The pictures came out pretty good; as good as could be expected. The problem, though, was getting it to focus. Now, it wasn't dark, it was just "dusk". Evening, with some table lamps on in the living room. taking pictures of my 5 dogs. So I framed up a shot, and when it went to focus, it went all the way to macro range, and then out to infinity (as it would if the cap was on). It did this twice before it finally focused on my westy's nose on its second trip back from infinity. I was quite let down, having just spent over $1,000 on this lens. I love it, but I'd think it should be quite a bit quicker to focus.

[Belmondo]

I was really always under the impression that the ability to focus in low light was a characteristic of the body and not the lens.

[Scottes]

Well the lens helps considering the max aperture, but this lens is f/2.8....

Ron, what are the numbers on that pic, ie; aperture, shutter, ISO? It will give us an idea of how much light was available. Seeing the pic will help too, but the numbers are more important.

[MDJAK]

My 24-70 is very fast focusing. It's a fantastic lens.

However, even with my 70-200 f2.8 IS, if there's little contrast, it will hunt from end to end. A dog's nose is kind of flat and featureless.

As has been stated, submit the picture with exif for evaluation.

[Ronald S. Jr.]

I was really always under the impression that the ability to focus in low light was a characteristic of the body and not the lens.

I guess i don't quite follow that...were you being funny?

[RandyMN]

Hey, depending on a lot of factors it happens with the best of lenses if not assisted by a flash unit. I would not let it diminish your respect for the lens.

[Belmondo]

I guess i don't quite follow that...were you being funny?

Sorry. I should have been clearer. The 'logic' for the autofocus resides within the camera and feeds instructions back to the focus mechanism in the lens.. Your lens on a 1Dm2 is going to behave very differntly than, say, on a 10D.

The inability of your camera to acquire focus quickly is not necessarily a problem with your lens, although it could be. It's much more likely to be a function of low light and your 20D's ability to deal with it. My 1Dm2 focuses much more surely than either my 20D or the XT.

Does that still sound funny?

[RandyMN]

Sorry. I should have been clearer. The 'logic' for the autofocus resides within the camera and feeds instructions back to the focus mechanism in the lens.. Your lens on a 1Dm2 is going to behave very differntly than, say, on a 10D.

The inability of your camera to acquire focus quickly is not necessarily a problem with your lens. My 1Dm2 focuses much more surely than either my 20D or the XT.

Does that still sound funny?

I was sort of thinking along the same lines as you were on this.

[kenyc]

My 24-70 is very fast focusing. It's a fantastic lens.

However, even with my 70-200 f2.8 IS, if there's little contrast, it will hunt from end to end. A dog's nose is kind of flat and featureless.

As has been stated, submit the picture with exif for evaluation.

Yep, I've had that happen even in bright sunlight at softball games. Maybe my camera is broke.

KAC

[Dante King]

I always thought that focus speed depended to a large part to the speed of the lens.

Junior do you have exif on those pics. Think Belmodo might be on to something.

[elTwitcho]

While I have to concede I've never used an L lense, I think it's possible that based on reviews, opinions and especially this forum you might just have developed unrealistic expectations about what this lense can do. I keep up on reviews even for stuff I'm not going to buy anytime soon because it interests me, and I get the feeling that if this lense couldn't nail the focus under these conditions, I doubt there is going to be any zoom lense that could.

Kind of like when some of us who started on digital bought our first SLR. There was always that moment of disapointment when you realized that your equipment can't do EVERYTHING and there are still constraints that are going to apply, no matter how good the equipment is. Just like I had to accept that 3200 ISO on my 10D wasn't remotely useable after all, maybe it's just a case of accepting that in difficult conditions the lense won't be perfect, but certainly better than most other options available.

Just my opinion naturally, I could very well be way off base also

[ddelallata]

Now I'm lost. I thought that the 20D had very accurate focusing on lenses with apertures of 2.8 and greater.

[RandyMN]

Now I'm lost. I thought that the 20D had very accurate focusing on lenses with apertures of 2.8 and greater.

Yes, but what lighting and contrast situations are you expecting this?

[CyberDyneSystems]

Autofocus speed and accuracy depends on three variables.. (in a nutshell/grand scheme type thing)

1: Camera body
2: Lens

I'll pause here as the two above ar ethe aspects that are discussed the most. In fact certain combos are mentioned regulary... the combo of lens and body is significant,. and both play a large roll in the total AF experience if you will. Put simply,. a 200mm f/2.8L will focus much faster on a 20D than 28-135mm will. It is also true that the same 200mm will focus even faster on the 1D bodies.

3. Environment/lighting
O-kay the third variable is more broad,. the environemnt,. most specifically the lighting, but also the contrast and angle plays a factor. More so with accuracy,. or the ability of the body/lens combo to lock on or find focus.

[Ronald S. Jr.]

I definitely don't think I've developed unreal expectations about what this lens can do...this will be my 4th L, 2nd of which is 2.8 constant ap (70-200L IS being the 1st). I know quite well what they can do, and what they're SUPPOSED to be able to do. I've taken thousands upon thousands of shots with L lenses. I think it was probably just the slight lack of contrast in the environment, as a few of you have said. I'll check on that.

However

I'll have to reenact the event...I deleted the pictures, because they were "nothing special".

[Scottes]

I always thought that focus speed depended to a large part to the speed of the lens.
The AF speed is certainly an aspect of the lens and it's ability to move the elements quickly.
But the body's ability to discern a focus point is also very important. Speed, though, is more in the lens. My 400mm L will acquire focus faster than my 100-400 - the prime is simply faster at moving the elements.

I get the feeling that if this lense couldn't nail the focus under these conditions, I doubt there is going to be any zoom lense that could.
I would think the same, but would wonder about either of the Canon 70-200 f/2.8 lenses. Or the Sigma 120-300. No experience comparing any of them, but they should all be close. I think.

Now I'm lost. I thought that the 20D had very accurate focusing on lenses with apertures of 2.8 and greater.
It does, but a 1DsMKII will be even more accurate with the same lens and scene. I remember reading somewhere that any of the "pro" body's AF is three times more accurate than the 20D/Rebel line. And I'm sure they're also faster, too.

[elTwitcho]

I definitely don't think I've developed unreal expectations about what this lens can do...this will be my 4th L, 2nd of which is 2.8 constant ap (70-200L IS being the 1st). I know quite well what they can do, and what they're SUPPOSED to be able to do.

No offence was intended, I just think based on what everyone else has experienced with this lense you'll end up being happy with it if you give it a bit more time. I didn't at all mean to question your level of expertise with quality lenses

[PetKal]

I know nothing.:oops:
However, If I were testing the AF capability of a 2.8 lens on 20D, I'd turn on the center cross pixel sensor alone and go for contrast transitions, both weak and strong, in a 12x12 room lit with 100 W min celing light.

From a good/deficiency-free lens, on a deficiency-free 20D I'd expect a fast and secure AF under those conditions, for most but weakest/non-existent contrast trasitions, be they vertical or horizontal.

I have no idea how Canon boys do this, but my hunch is that.....

The sensitivity to contrast is a function of light that the lens funnels to the AF sensors, and the sensors themselves. The speed and decisiveness of AF is a function of the camera AF control circuit (master controller) + lens actuator/drive (slave) controller.

Heck, how do they really do that ?

[mebailey]

I guess i don't quite follow that...were you being funny?

I think he being serious. The high end bodies will auto focus at smaller fs and have more focusing points to help out in tough situations.

[Belmondo]

I think he being serious. The high end bodies will auto focus at smaller fs and have more focusing points to help out in tough situations.

Thanks. My 'funny' answers are usually much shorter. I normally won't go to that much trouble for a joke.

[Music to my eyes]

In dim light I find my 24-70L will hunt less than my 70-200 IS (eg., for same subject in very dim light.) I think the 24-70L has terrific AF performance. It still does hunt on occasion, but that is really pushing it (low contrast subjects in poor light.)

Eugene

[nosquare2003]

Thanks. My 'funny' answers are usually much shorter. I normally won't go to that much trouble for a joke.

So, is the below thread is a joke?
http://photography-on-the.net/forum/showthread.php?t=102983&highlight=hkfever

Excuse me for off-topic.

[Belmondo]

Yeah.

One word. It was a joke.:lol:

[malla1962]

No problems with mine.:D:D

[nosquare2003]

Yeah.

One word. It was a joke.:lol:

I just can't stop laughing for your one-word joke.

[bachscuttler]

I have to work with lower end gear (I'm married with 4 kids and another on the way).

In low light and poor contrast conditions (type of shot permitting) I don't get upset about using manual focus.

If I'd forked out big bucks for an L lens I might though :confused:

[Maureen Souza]

I just can't stop laughing for your one-word joke.

Me either......that was way too funny:lol: :lol: :lol: :lol:

[HKFEVER]

So, is the below thread is a joke?
http://photography-on-the.net/forum/showthread.php?t=102983&highlight=hkfever

Excuse me for off-topic.

Wow, did I miss anything?:confused:

[Andy_T]

I guess i don't quite follow that...were you being funny?

Ronald, let me tell you something before a moderator has to do ...

Aggression usually is a bad way to compensate for ignorance.

Behave on the forum like you would behave at home, in a conversation with somebody else you respect.
(OK, maybe this *is* how you behave at home :rolleyes: )

As to your problem ... have you tried to compare the 24-70 to your 70-200?
It maybe would be conclusive to see if one of them is focusing significantly better than the other under the exact same conditions.
(same time, same target, same settings, both lenses set to 70 mm focal length)

Best regards,
Andy

[nosquare2003]

Wow, did I miss anything?:confused:

Sorry, I couldn't resist.

[HKFEVER]

Sorry, I couldn't resist.

Sorry I still don't understand what you can't resist, I did read this thread couple times.

For AF speed, it does depend on the body.

[Andy_T]

He was referring to Belmondo's one word joke
As far as I know, there's only one comment in that thread that is a single word (a very short one, to that :wink: )

Best regards,
Andy

[PetKal]

I think most of us should know the feeling of let-down when a long and much desired piece of gear (lens), and a very expensive one at that, appears to be flawed in some way.

When that happens with an "iconic" lens such as 24-70, and some help is being sought from the Forum, the disappointed lens owner is sometimes being confronted with commentary on "operator error", etc. , at the very time when they could be losing their sense of humour rapidly.

Be that as it may, I am sure Ronald will sort out this AF problem competently and to his ultimate satisfaction.

[BugEyes]

As someone said make sure you are using the center AF point only, the extra sensitive one. And don't expect it to lock focus on a dogs noose if the only source of light is a lightbulb. The 24-70 range is very usable and I'm sure it will serve you well in the long run.

[Salleke]

Well, so I got my 24-70L via UPS today that I purchased from a fellow POTN'er. It's a wonderfully built, perfectly sharp, beautiful lens. However, this evening, an hour and a half ago or so, after I had been testing it out for a while, I decided to do some low light stuff. The pictures came out pretty good; as good as could be expected. The problem, though, was getting it to focus. Now, it wasn't dark, it was just "dusk". Evening, with some table lamps on in the living room. taking pictures of my 5 dogs. So I framed up a shot, and when it went to focus, it went all the way to macro range, and then out to infinity (as it would if the cap was on). It did this twice before it finally focused on my westy's nose on its second trip back from infinity. I was quite let down, having just spent over $1,000 on this lens. I love it, but I'd think it should be quite a bit quicker to focus.

Ronald - Even the best lens and camera will hunt sometimes when trying to obtain focus.
There are dozens reason why, when and how. I've owned the 24-70 and I noticed that
it was hunting sometimes to obtain focus in low light and on a subject with no or low contrast.
IMHO there is nothing to bee worried about your lens. Just accept that it can happen on
some rare occasions. Good luck and enyoj your lens.

[HKFEVER]

Add a ST-E2 on 350D and 20D will improve the AF speed a lot in a very dark setting.:cool:

[JMHPhotography]

Forgive my ignorance... but how exactly does a speedlight transmitter help with AF speed? Your pictures are OUTSTANDING btw.

Add a ST-E2 on 350D and 20D will improve the AF speed a lot in a very dark setting.:cool:

[Jon]

It can be configured to send out a focus-assist pattern so the camera has a well-enough illuminated target for autofocus to be able to function.

[Ronald S. Jr.]

Ronald, let me tell you something before a moderator has to do ...

Aggression usually is a bad way to compensate for ignorance.

Behave on the forum like you would behave at home, in a conversation with somebody else you respect.
(OK, maybe this *is* how you behave at home :rolleyes: )

As to your problem ... have you tried to compare the 24-70 to your 70-200?
It maybe would be conclusive to see if one of them is focusing significantly better than the other under the exact same conditions.
(same time, same target, same settings, both lenses set to 70 mm focal length)

Best regards,
Andy


I wasn't trying to be aggressive...I really didn't know what he meant...I thought he was joking. Sorry for any misunderstanding, belmondo. I wasn't trying to be mean or anything. :confused:

[Ronald S. Jr.]

No offence was intended, I just think based on what everyone else has experienced with this lense you'll end up being happy with it if you give it a bit more time. I didn't at all mean to question your level of expertise with quality lenses

I'm DEFINITELY not an expert at anything having to do with photography...I'll admit that right now! :lol:

[Andy_T]

I wasn't trying to be aggressive...I really didn't know what he meant...I thought he was joking.

Well, another good example for one users innocent comment being misunderstood by somebody else.
Sorry for that from my side, too.

Best regards,
Andy

[Belmondo]

To the extent that I have a certain 'reputation' for often being insincere, I will certainly be happy to shoulder responsibility for any confusion arising from my comment.

No problem here.

[schmoelzel]

I can vouch for the body being as (if not more) important when it comes to AF and speed of AF. When I switched to a 1D body earlier this year, the first thing I noticed was that suddenly my lenses seemed to hit focus MUCH quicker than my previous DRebel. When I did some more reading, it was obvious that a camera with a 45-point focus meter will outperform one with 7 focus points. I find that all the lenses I know own are extremely fast to AF and I know that this is mainly due to the camera body.