# 5D3 vs 6D AF in low light



## skitron (Dec 15, 2012)

So I just sent a 6D back for issues other than AF and ISO and get in a 5D3 and after a couple of hours with it all I can say is the 5D3 center point is a joke compared to 6D in low light. 5D3 won't focus at all on fabrics in moderately low light that 6D locks in well under a second. 5D3 is noticably noiser at hi ISO as well.


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## Drizzt321 (Dec 15, 2012)

skitron said:


> So I just sent a 6D back for issues other than AF and ISO and get in a 5D3 and after a couple of hours with it all I can say is the 5D3 center point is a joke compared to 6D in low light. 5D3 won't focus at all on fabrics in moderately low light that 6D locks in well under a second. 5D3 is noticably noiser at hi ISO as well.



What lens were you using with it? If it's the 24-105 f/4, the extra high precision points aren't used. Not sure if that's the case or not with the 6D. If you've got a f/2.8 or better lens, at the least the center AF points can use the extra high precision points.


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## skitron (Dec 15, 2012)

100L


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## Drizzt321 (Dec 15, 2012)

skitron said:


> 100L



Ok, so at a minimum the center point should have used the extra high precision AF sensors. And you tried the 6d under identical conditions? It's a fact that the 6D has a more significant -ev sensitive center point. However, have you tried shooting with more points, or used AI-Servo across all points, or other similar shots where the large number of AF points and higher precision AF points would come in useful? While I'll definitely give you the center point on the 6D will almost certainly function better in extremely low light than the 5d3, I question calling it a joke.


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## skitron (Dec 15, 2012)

Drizzt321 said:


> While I'll definitely give you the center point on the 6D will almost certainly function better in extremely low light than the 5d3, I question calling it a joke.



The 5D3 center works fine if you put enough light on the target, other than being pretty slow in comparison. When I say its a joke, that's in comparison to 6D in low light, I'm not saying its a joke "in general". 

I put it in one-shot release priority and that sped it up a bit but still very sluggish in morginal light where 6D doesn't complain at all.


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## skitron (Dec 15, 2012)

Don't get me wrong, the 5D3 is a good system and a known quantity and I'm sure when it comes time to shoot actual pictures I'll be happy with it and in most cases not really need to focus on stuff too dark to discern in the viewfinder. 

Again, my original comment was supposed to be specific to very low light only and in comparison to 6D center performance only. 

I definitely like the colors out of the 5D3 better. Not sure if my 6D was a dud or not but it had a pretty strong shift towards red kinda like a D800 shifts towards green. I stumbled on it just because a flower in my backyard is a light shade of pure blue and really makes the issue stand out. The copy of 6D I had renders it a tinge purple even after lowering the color temp and messing with the red channel in the RAW processor. The 5D3 looks spot on and not really the purple tinge even warming up the color temp past anything reasonable.


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## mclaren777 (Dec 15, 2012)

http://www.reikan.co.uk/focalweb/index.php/2012/12/af-consistency-comparison-nikon-canon-phase-detect-contrast-detect/


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## sdsr (Dec 15, 2012)

skitron said:


> So I just sent a 6D back for issues other than AF and ISO and get in a 5D3 and after a couple of hours with it all I can say is the 5D3 center point is a joke compared to 6D in low light. 5D3 won't focus at all on fabrics in moderately low light that 6D locks in well under a second. 5D3 is noticably noiser at hi ISO as well.



When you say "noticeably noisier", are you referring to raw files that haven't been subjected to noise reduction or in-camera-created jpegs? I'm currently renting a 5DIII to compare to my 5DII in low light (and otherwise), and I'm interested in the 6D too because of its low light abilities; so I'm interested in your reactions. 

Coming to the 5DII from a Pentax K-5 I was greatly impressed by the Canon's faster and more accurate focusing (among other things), so I'm always amused to see people here complaining about the 5DII; but I do get the impression (and that's all it is; I've done nothing resembling scientific comparisons) that the lenses I've tried on the 5DIII focus more consistently precisely accurately than on the 5DII in any sort of light (not that I've had many complaints re the 5DII).


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## Area256 (Dec 15, 2012)

I'd guess that the focus point areas on the 5D3 is smaller than that on the 6D center point. i.e. the surface area of the 6D center point is likely twice as large to collect an extra stop of light vs the center point of the 5D3. That may also make it better at picking up areas of contrast. However I would think putting the 5D3 into one of the point spread options (i.e. using 5 or 9 points in a square) would give you a better chance of catching something than with the 6D large center point. I did find playing with the 5D3 in the store that you had to be more careful about the areas of contrast you picked when using just one point.


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## rlarsen (Dec 16, 2012)

I can't comment on the new 6D because I haven't seen, one but I sure am impressed with the low light AF performance of my 2 5D MK lll bodies. Mine work extremely well in very dark conditions. I use a 24-70, 16-32, 70-200, 300 2.8 and 300 f4

Camera selection in my opinion is usually based many features and specs. If the 6D focuses better in low light that's really great. 

We want our cameras to hold value, and I think most of us want new models to feature improvements. The reason I began following CanonRumors.com was to be informed of new equipment on the way so I can make smart purchasing decisions. I imagine the 7D will focus better than the 6D. Its really only a problem if you buy the 6D a month or two before the new one comes out.


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## Area256 (Dec 16, 2012)

mclaren777 said:


> http://www.reikan.co.uk/focalweb/index.php/2012/12/af-consistency-comparison-nikon-canon-phase-detect-contrast-detect/



Ok that's strange... Contrast detect should be better than phase detect in terms of precision and accuracy (it's just a lot slower) - that's what LensRentals.com found, and I trust them to be right - and kind of suspect something is wrong with that test. I had a 60D which was very similar to the 7D, and it had great contrast detect AF precision (if you didn't mind waiting for it).


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## skitron (Dec 17, 2012)

rlarsen said:


> I can't comment on the new 6D because I haven't seen, one but I sure am impressed with the low light AF performance of my 2 5D MK lll bodies. Mine work extremely well in very dark conditions.



Again, my original comment was only in a relative sense for a specific situation. I had an oportunity to shoot my 5D3 in pretty low light and it did well, but I did miss a couple of shots where it failed to lock that the 6D, based on my testing, would have handled no problem. 

On the flip side of the 6D vs 5D3 AF comparison, I am already spoiled with the number of 5D3 cross sensors and what that means for composition.  

Two very nice tools to choose from IMO, and 6D wins the low light focus battle on the center point by a meaningful margin IMO. But in the end, 5D3 is a better overall fit for me personally.


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## Wilmark (Dec 17, 2012)

I find its amazing that there are so many posts here that appear to be defending the 5DMk3 ability to focusing ability in low light. Guys, the 5D3 are many things and it has a great focusing system - but its ability to focus in the dark is atrocious, compounded by the lack of a pop up flash i would say it is one of the most significant short comings of the 5D3. Canon recognizing this have improved low light focusing in the 6D and I am sure that every pro dslr released henceforth will be superior to the 5D3 in low light focusing. If this could be improved via firmware I wish canon would fix this. There is no easy solution for this other than to walk around with a flash light. I heard that there was a laser assist someone was working on but i have not seen it.


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## davidbellissima (Dec 17, 2012)

The 5D3 is very slow to focus in very low light, regardless of how the focusing is configured. This is my biggest complaint about the 5D3, which is otherwise a brilliant camera.


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## Chuck Alaimo (Dec 17, 2012)

Wilmark said:


> Guys, the 5D3 are many things and it has a great focusing system - but its ability to focus in the dark is atrocious, compounded by the lack of a pop up flash i would say it is one of the most significant short comings of the 5D3.



Pop up flash? Really????? I have used my 5d3 in many low light situations and it has performed fine.


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## Zlatko (Dec 17, 2012)

Wilmark said:


> I find its amazing that there are so many posts here that appear to be defending the 5DMk3 ability to focusing ability in low light. Guys, the 5D3 are many things and it has a great focusing system - but its ability to focus in the dark is atrocious, compounded by the lack of a pop up flash i would say it is one of the most significant short comings of the 5D3. Canon recognizing this have improved low light focusing in the 6D and I am sure that every pro dslr released henceforth will be superior to the 5D3 in low light focusing. If this could be improved via firmware I wish canon would fix this. There is no easy solution for this other than to walk around with a flash light. I heard that there was a laser assist someone was working on but i have not seen it.


Most of my photography with the 5D3 is in low light and I find the focusing to be excellent, at least as good as any other camera I've used in the past 10 years. And most Canon flashes have a built-in autofocus assist light, so I don't know why anyone would need a laser assist.


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## gundul (Dec 18, 2012)

Zlatko said:


> Wilmark said:
> 
> 
> > I find its amazing that there are so many posts here that appear to be defending the 5DMk3 ability to focusing ability in low light. Guys, the 5D3 are many things and it has a great focusing system - but its ability to focus in the dark is atrocious, compounded by the lack of a pop up flash i would say it is one of the most significant short comings of the 5D3. Canon recognizing this have improved low light focusing in the 6D and I am sure that every pro dslr released henceforth will be superior to the 5D3 in low light focusing. If this could be improved via firmware I wish canon would fix this. There is no easy solution for this other than to walk around with a flash light. I heard that there was a laser assist someone was working on but i have not seen it.
> ...



I am wondering, is 5D3 with flash assist light beat the EV-3 low light focusing of 6D?

I currently use 5D2 with 430exII... Still undecided to go to 5D3 AF or 6D low light... Anyone has any scientific idea on how low 5D2 with 430exII can focus?


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## Wilmark (Dec 18, 2012)

It is obvious that some users experience difficulty in what is to them low enough light where the camera has difficulty in focusing. Saying things like "I shoot alot of low light" doesnt mean anything really... One many lows may be another mans hights, you want a good documented example of what we are talking about see here http://youtu.be/omTo7UxbJX8?t=8m6s. I for one hardly take my flash with me - the camera takes great pictures in low light with some help from lightroom, but getting it to focus sometimes is a problem.


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## Chuck Alaimo (Dec 18, 2012)

Mikael Risedal said:


> Chuck Alaimo said:
> 
> 
> > Wilmark said:
> ...



the 6d doesn't have a pop up flash either. I have not laid hands on the 6d yet, but I am considering picking one up as a backup/secondary body. what i will say is that the only time i have had issue with the AF on the mk3 was in situations where I wouldn't have gotten a usable shot anyway! So sorry, i don't really see the issue.


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## Woody (Dec 18, 2012)

mclaren777 said:


> http://www.reikan.co.uk/focalweb/index.php/2012/12/af-consistency-comparison-nikon-canon-phase-detect-contrast-detect/



Thanks for the link. Quite a revelation. I hated the 7D single shot AF for its poor accuracy, but never expected its contrast AF to be so poor as well.


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## dlleno (Dec 18, 2012)

Wilmark said:


> Saying things like "I shoot alot of *low light" doesnt mean anything *really...
> 
> ...I for one hardly take my flash with me - the camera takes great pictures in *low light * with some help from lightroom, but getting it to focus sometimes is a problem.



so....what IS low light to you? are you approaching the EV limits of the AF system, or well within them? These tests are all are very enagaing, but if we could express the level of light in terms of the EV numbering system understood by the photography world, it would be more meaningful. Can someone please explain to me why this is either difficult or unattractive? 

Most of the the tests in the video were reasonably done. For example, the guys did a good job of exposing the "snappy" (5D3) versus "heasitant" (D800) AF in the studio, which was revealing, to be sure, especially when acknowledged by the confessed Nikon shooter. Notice he didn't even say anything like "when side by side there is really no important difference", as he did in the shadow DR comparison. for the studio lighting condition the AF performance of the 5D3 was a definate, measureable, and meaningful advantage in real situations. 

The low light focusing shootout was disapointing to me because it didn't really test the capabilities of the AF system's thesmselves in low light. All they did was point out that the D800 has an AF assist capability that is useful at reasonable portrait distances when the visible AF assist light is acceptable. Good information, to be sure, but low-light shooters don't necessarily want visible AF assist! What they should have tested is situations where AF assist is either impossible (due to distance) or undesired. 

Back to the subject at hand, are you all saying that the 5D3's AF performance in low light (without flash attached) isn't commensurate with the situation, i.e. shutter speeds that would be typical, subject movement etc? Unless I've missed something, the only consistent performance issue meaningfully described here is that camera does not utilize the AF-assist beam from the flash very well.


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## skitron (Jan 5, 2013)

Just a follow-up to this...

After experiencing my 200L f/2.8 and how well it focuses in low light vs my 100L with 5D3, I read in the 5D3 manual that the 200L is in AF group A while 100L is in group C, meaning the 200L uses all of the dual cross f/2.8 AF sensors while the 100L uses none of them. 

So this explains things since according to p95 of the 6D manual, the 100L apparently uses the maximum capabilities of the 6D center point whereas on the 5D3 Canon has limited the 100L to use only diminished center point capabilities. 

Given this, using the 100L to compare the 6D and 5D3 center points was not an apples to apples comparison. And IMO if Canon allows the 100L to use the max capabilities of the 6D center point, Canon needs to offer a firmware fix for the 5D3 and 100L...


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## EvilTed (Jan 5, 2013)

It also looked like he was using a 50mm 1.2 L for the low light tests.
This lens isn't sharp in good light wide open, so it's hardly surprising that the Nikon was better 

An interesting and pretty fair review.
Add to this the AF problems that are plaguing D800 users and I'm glad I made the switch to Canon.

ET


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## hemidesign (Jan 5, 2013)

folks, don't forget about Bryan Review from the-digital-picture website.

"I can focus the 6D's center point on a subject with reasonable contrast down until auto exposure gives me a setting of 160 at 10 seconds and f/2.8 (really dark) with the Canon EF 24-70mm f/2.8 L II USM Lens mounted (note that the 6D's metering range spec is listed at EV 1-20). The Canon EOS 1D X's center point could not focus on the same subject with the same lens mounted. Note that the 6D focuses very slowly under these dismal lighting conditions - but locking slowly is far better than failing to lock."

"Made to focus in very low light condition: EV-3 is the strongest low light AF performance of any Canon AF system at Canon EOS 6D review time. EV-3 is the equivalent of moonlight."

So..1DX has the same AF system as the 5Dmk3.. so 6D does a better job focusing at dark conditions.. better FROM ANY CANON CAMERA TO DATE!


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## dlleno (Jan 19, 2013)

I wish folks would be specific in test results on this topic, as many here have. for eample, has anyone noticed that in this video:

Canon 6D Vs. 5D Mark III Hands On Review

at about 10:50 the reviewer shows a still life shot taken by a 5D3 and 6D at a light level Just short of -3EV? yes, just short of -3EV. ISO 200 15 seconds f/2 is approximately -3EV, so a 13 sec exposure indicates less available light than -3EV, assuming the photo is properly exposed. 

this is beyond the AF sensitivity specification listed for the 5D3, which is -2EV for all focus points. It is even (very slightly) beyond the AF sensitivity spec for the 6D, who's center point is spec''d at -3EV sensitivity . Anyway, the reviewer indicated no problems whatsoever with AF for either camera at that light level. However, here's the "but": he didn't say how long it took to achieve AF lock for each camera and he didn't say at what distance the lens was focused prior to locking on the subject. :-(


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## Magnardo (Jan 19, 2013)

Nice video but,.....I have never met or heard anyone that says "on that"as much as this guy.
It seems he is doing it after every sentence.


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## tortilla (Jan 19, 2013)

Zlatko said:


> Most of my photography with the 5D3 is in low light and I find the focusing to be excellent, at least as good as any other camera I've used in the past 10 years. And most Canon flashes have a built-in autofocus assist light, so I don't know why anyone would need a laser assist.



When shooting low key portraits, models don't like it to be dazzled by the assist flash.


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## Marsu42 (Jan 19, 2013)

tortilla said:


> When shooting low key portraits, models don't like it to be dazzled by the assist flash.



Animals often also aren't very enthusiastic about getting the af assist in their eye (and that's why I usually focus) - unfortunately the 60d (af rated up to +0.5lv) uses af assist very often, so I'm looking forward to the 6d.


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## Zlatko (Jan 19, 2013)

tortilla said:


> Zlatko said:
> 
> 
> > Most of my photography with the 5D3 is in low light and I find the focusing to be excellent, at least as good as any other camera I've used in the past 10 years. And most Canon flashes have a built-in autofocus assist light, so I don't know why anyone would need a laser assist.
> ...



I was responding to the statement that the 5D3's ability to focus in low light is atrocious. On the contrary, I've found it to be excellent in low light, and that is without any autofocus assist light. However, an autofocus assist light can be used if needed. It is not an "assist flash" and doesn't "dazzle". To clarify, it is the red AF assist light available on most Canon flashes and on the ST-E2. The red AF assist light can be used for AF assist only, with no flash being emitted. The flash is on, but set to not fire. It's not ideal, and it's usually not necessary, but it's available if needed.


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## J.R. (Jan 19, 2013)

Zlatko ... Thanks for the info


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## dlleno (Jan 19, 2013)

Zlatko can you express what you mean by "low light" in terms that can be correlated to the results of others', as well as the published specifications for AF sensitivity? short version: What does "low light" mean to you in terms of EV(100)?


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## Zen (Jan 20, 2013)

The definition of "low light" is critical to these conversations, and because it is so subjective, the debate is almost meaningless. In my case, I'm sitting here in my den, appx. 12' by 24', with one 100 watt tungsten bulb in the corner lamp. The lamp is behind me and when I focus on the opposite wall, containing well filled book cases of aged cherry, my 5D3 clicks to focus quite easily and without any delay. I call this low light, and have no problem at all. I cant imagine a faster or sharper focus! And when I take the time to set the custom WB after use of a gray card, the images come out perfectly.

Perhaps my standards are lower than others, but I couldn't be more satisfied with my 5D3. ;D 

Zen


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## Marsu42 (Jan 20, 2013)

Zen said:


> The definition of "low light" is critical to these conversations



Furthermore "achieving focus" needs definition, because in problematic lighting conditions the camera will take more time to focus - I hope the detailed dpreview.com 6d review will tell us at last if the -3lv rated 6d is getting a focus lock faster @-2lv than the 5d3 which is maxed out in this level.


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## J.R. (Jan 20, 2013)

Marsu42 said:


> Zen said:
> 
> 
> > The definition of "low light" is critical to these conversations
> ...



It should based on the theory. As I normally shoot in the evenings / night, I am really looking at the 6D as a replacement for the 7D if this is confirmed. Too bad in my country there is no option of renting the 6D or I would have checked it out by now. 

For me the AF issues have arisen only in near darkness situations. The AF seems to continually hunt from end to end. Otherwise the AF system is near perfect.


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## dlleno (Jan 20, 2013)

why is it so hard to state the light level in terms of EV(100)? if you have taken a picture, that is exposed properly, you have the necessary information


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## Zen (Jan 20, 2013)

I wonder . . . do we expect the camera to "see" better than we ourselves can? For example, I can barely make out shapes in "near dark" situations, yet some expect the camera to do better than that. Is that logical? :-\

Zen


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## dlleno (Jan 21, 2013)

Zen said:


> I wonder . . . do we expect the camera to "see" better than we ourselves can? For example, I can barely make out shapes in "near dark" situations, yet some expect the camera to do better than that. Is that logical? :-\
> 
> Zen


we expect the camera to af in the light levels specified by canon, not those specified by our eyes. why is it so difficult to express the light levels of interest in the terms specified by canon? thats the comparison of value.


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## Zlatko (Jan 21, 2013)

dlleno said:


> Zlatko can you express what you mean by "low light" in terms that can be correlated to the results of others', as well as the published specifications for AF sensitivity? short version: What does "low light" mean to you in terms of EV(100)?


Sure, looking at recent photos in Photo Mechanic, I would say that typical "low light" photos were in the range of EV 1.2 to EV 4.0. These would be interior scenes at night, photographed without flash and without an AF assist light. Those EV numbers correlate to these exposures:
EV 1.2 = ISO 3200, f/1.2, 1/50th
EV 4.0 = ISO 800, f/1.6, 1/50th


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## RLPhoto (Jan 21, 2013)

Lol. I just used my 5D3 strobist with no AF assist beam with just a distant street lamp for a source of light to AF. If the 6D is any better, wow but the 5D3 is still the best AF camera I've ever used.


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## dlleno (Jan 21, 2013)

Zlatko said:


> dlleno said:
> 
> 
> > Zlatko can you express what you mean by "low light" in terms that can be correlated to the results of others', as well as the published specifications for AF sensitivity? short version: What does "low light" mean to you in terms of EV(100)?
> ...



Ahh thank you. So 3-6 stops brighter than published minimum AF sensitivity


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## Wildfire (Jan 25, 2013)

Marsu42 said:


> Animals often also aren't very enthusiastic about getting the af assist in their eye (and that's why I usually focus) - unfortunately the 60d (af rated up to +0.5lv) uses af assist very often, so I'm looking forward to the 6d.



The 60D doesn't have an AF assist beam, it just uses the built-on flash for AF assist.

Try mounting a 430EX or higher model speedlight to your 60D and you'll get an unobtrusive red AF-assist beam.


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## Marsu42 (Jan 26, 2013)

Wildfire said:


> Marsu42 said:
> 
> 
> > Animals often also aren't very enthusiastic about getting the af assist in their eye (and that's why I usually focus) - unfortunately the 60d (af rated up to +0.5lv) uses af assist very often, so I'm looking forward to the 6d.
> ...



Thanks for enlightening me :->



Wildfire said:


> Try mounting a 430EX or higher model speedlight to your 60D and you'll get an unobtrusive red AF-assist beam.



If you look at my gear list (to the left) you'll see that I've got a 430ex2 & 600rt ... it's just my experience the red af assist is not as "unobtrusive" as you seem to think. And I never do pre-flash, it's just so annoying.

I just stated "60d" because a af system rated to up to +0.5lv is bound to use af assist more often than say the 6d that is supposed to focus up to -3lv.


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## jonathan7007 (Jan 27, 2013)

All,
The wild card in these discussions is what appears to be some variability in the 5Dmk3 copies'AF abilities. I feel I got a flawed body and it seems slower than it "should". Unscientific, absolutely, and I should work up a test here that Canon Service can replicate. These discussions are helpful for establishing what the limits should be. My comparison is my 5Dmk2. For any of the tests described the next level is bringing a lot of 5Dmk3 bodies into the same setup and looking for variations in "lock" time. I bought my body in May last year.

I didn't figure this out in time to exchange it. My bad! Canon has already looked at this body once. 

I need to find an acquaintance with a 5Dmk3 and time to compare. That would be interesting.

Aaaaarg. <anger>

jonathan7007


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