# 6D vs 5Diii vs 5Dii - Speedlite AF Focus Beam Assist Tests



## MichaelTheMaven (Dec 12, 2012)

Had several requests to measure the focusing speed of the 6D vs 5Diii vs 5Dii using a Speedlite (in this case 600ex) in low light conditions. Its a redo of the other focusing test I did this week, only this time using the red-af assist light. 

Target 1 Evenly exposed at 1/60, 2.8 ISO 400, about 20 feet away
Target 2 Underexposed about 7 stops with the same settings, about 4 feet away

I ran each camera through 30 focus locks back and forth. 

Interesting results:

Canon 5Dii - 45 seconds
Canon 6D - 52 seconds
Canon 5Diii - 70 seconds

I should note 2 things: the 6D does very well even without the AF assist beam. The 6D & 5Diii both feel as if there are 2 stages of focus, a larger followed by a smaller step. The 5Dii seems to lack this. 

Let me know if you guys have any questions. 

MM


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## gilmorephoto (Dec 12, 2012)

Very interesting results. Do you have another model of flash that you can repeat the test with to help determine if it is the body or flash or specific combination? I'm still with out my T1i and can't do the same test yet, but will soon I hope. Thanks again!


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## Robert Welch (Dec 12, 2012)

I have heard that the 5D3 (and I assume the 6D as well) does a focus confirmation in acquiring focus. That is, it achieves focus, then does a confirmation check before shutter release. You can overide this in the menu by changing the shutter release priority from focus priority to shutter release priority in the AF menu. This double confirmation of focus acquisition is new with the 5D3, not a function of the 5D2 AF. This may be the 2nd stage of AF that Michael is noticing, and probably part of the reason this camera seems to have a higher 'hit' ratio with regards to in focus images that most users, including myself, seem to get with this camera as compared to older Canon cameras.


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## MichaelTheMaven (Dec 12, 2012)

I can check both of these. Good insights. 

M


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## Zlatko (Dec 12, 2012)

I don't have a 1D series camera currently, but in the past I always had the feeling that the 1D series had a bit of extra lag when using flash compared to any of the xxD series. I believe this wasn't the case with the original 1D, but started with the 1DII or 1DIIN. It may be that the 5D3 has inherited this from the 1D series, along with the AF system generally, perhaps trading speed for accuracy.


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## Louis (Dec 12, 2012)

Micheal please can you post your results on these links also

http://www.canonrumors.com/forum/index.php?topic=10706.45

http://forums.usa.canon.com/t5/EOS/5D3-AF-assist-beam-slower-focus/td-p/2277


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## Louis (Dec 12, 2012)

70 Seconds is appalling


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## Dylan777 (Dec 12, 2012)

Great info Michael...."Canon 5Diii - 70 seconds". How wonder people complaining about this issue lately.

I guess "Camera of The Year" is not that perfect


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## M.ST (Dec 12, 2012)

RE to: You can overide this in the menu by changing the shutter release priority from focus priority to shutter release priority in the AF menu. 

But if you do this, then the first images maybe out of focus. You can compare the 5D Mark II only to the 5D Mark III if you don´t touch the setting.

I am very happy with the 5D Mark II focussing speed in low light with an assist beam.


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## Mt Spokane Photography (Dec 12, 2012)

How did you determine that focus was achieved? I place the camera in 1 shot AF so that it will not fire until focus is achieved, and do a full button press. The camera fires as soon as focus is achieved, which can be long before the AF indicator lights. 
So, are you measuring time for focus to be reached, or time for the AF indicator to light?


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## digital paradise (Dec 12, 2012)

Someone stated this is not working. Images are OOF. It may be on Canon forums. I have to say. I keep testing this and it and I think it is working. 

Only time it takes an extra second is when I really put the lens OOF on purpose. It takes second the the USM to bring it home. Even them my shot was in prefect focus. 

I'm going to continue testing this. I have not gone live with this yet. More tests from other people would be helpful.

I just thought of something while writing this. I had also read that the first time on a new subject the AF assist would take 3 times but then once achieved it was quick. So if unsure off AF consistency do the full press for the first shot then half press for subsequent shots. I'm going to try it out. 

This may be an excellent "temporary" solution but I'm still won't be thrilled about changing my shooting style.


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## Chuck Alaimo (Dec 12, 2012)

ScottyP said:


> Thanks Michael for running that time comparison! A lot of folks had that exact question in their minds for a couple of months now!
> 
> I imagine 70 seconds would seem like an hour if you were shooting a wedding with everyone staring at you as the seconds tick by, and you start to sweat.



5d3 owner here, has used it on multiple weddings. I don't find the lag time to be too much of an issue because the AF lag only happens in extremely dark situations -- like when your going with no flash ISO 6400-12,800, f2.8 or lower, 1/50th SS ---- in the kind of situations you probably would get a shot at all with a 5d2 or 7d. For a while i was running with the 7d 5d3 combo and found that yes, the 7d would achieve focus quicker, but the shot was totally unusable...

shot posted from a reception, ISO 6400, f2.8, 1/100th, 140mm 

Also, i have found the focus speed to vary depending on lens used, and aperture used, and which AF mode I'm in. Using either of my primes wide open, with single point AF the lag is much more noticable. But, at f2.8-4 losck is achieved much quicker. And if I used expanded AF points focus is also quicker (less precise though). I see it as a trade off, if I am shooting wide open on prime lenses, I'll accept the lag time in order to get a precise shot! So for me, while it would be nice if it locked quicker, I'll take the trade off!


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## Chris Burch (Dec 12, 2012)

Zlatko said:


> I don't have a 1D series camera currently, but in the past I always had the feeling that the 1D series had a bit of extra lag when using flash compared to any of the xxD series. I believe this wasn't the case with the original 1D, but started with the 1DII or 1DIIN. It may be that the 5D3 has inherited this from the 1D series, along with the AF system generally, perhaps trading speed for accuracy.



Sadly my 1DX suffers from the same lag as the 5D3. I've been using both quite a lot in the past few months and the delay to lock focus is painful when you have people posed and waiting for the shot to happen.


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## dlleno (Dec 12, 2012)

Michael -- re 70 seconds. what EV level are we talking about? I can see the evidence of more accurate AF here, in the 5D3, perhaps via more retries and/or higher credence level before the system is satisfied. But I want to know do these numbers represent a severe corner case test or a comon real-world scenario? even the speed deamon 5Dii took 45 seconds which is also an eternity if you have groomsmen in black tuxdos in a dimly lit church foyer. 

I'm getting the feeling, from the wide variety of responses on this topic, that:

1. we still do not have a solid, consistent, "repeatable by a monkey" use case representing a real scenario consistent with the marketing language, that would communicate to Canon that the camera does not function in the way it was advertized. 

2. there may even be some hardware related component here that is similarly not well understood. Canon may have even changed something in the manufacturing process that would reduce the exposure of this problem to older 5D3s . I wonder, for example, what portion of the mis-behaving 5D3s have s/n lower than RustyTheGeek's replacement camera?


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## neuroanatomist (Dec 13, 2012)

Chuck Alaimo said:


> ...i have found the focus speed to vary depending on ... aperture used, and which AF mode I'm in. Using either of my primes wide open, with single point AF the lag is much more noticable. But, at f2.8-4 losck is achieved much quicker.



If true, that's certainly a firmware design choice by Canon. AF is always done wide open, regardless of the selected aperture. It's possible that Canon elected to trade speed for accuracy when a narrower aperture is selected and the tolerance for slight AF errors is higher.


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## RustyTheGeek (Dec 13, 2012)

dlleno said:


> I wonder, for example, what portion of the mis-behaving 5D3s have s/n lower than RustyTheGeek's replacement camera?



FYI, the replacement 5D3 I received from Beach Camera that performs better has a *4* in the 6th digit and ends in *4736*. So my current serial number is *xxxxx4xx4736* if that matters or helps anyone. By comparison, the 1st problem 5D3 that I returned had a serial = *xxxxx4xx4037*.

Not sure if the serial number is relevant to the problem but there it is.


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## DeckardSolo (Dec 13, 2012)

My serial is *xxxxx4xx5xxx* and has the IR focus issue. I've had it for 2 weeks from an authorized seller.
In -2EV of light my Rebel 550D was faster than the 5D3 (1/2s vs 1s). In 1EV of light the 5D3 is faster. The test was simple. Fully depress the shutter simultaneously on both bodies to see which shot first (images were in focus). 

[The setups were different (5d3+600ex+70-200ii vs 550D+580ex2+24-70v1) but I found in previous tests that combinations of lens and flash did not make a difference to the outcome. Subject was a uniform tiled wall at 8 feet.]


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## dlleno (Dec 18, 2012)

DeckardSolo said:


> My serial is *xxxxx4xx5xxx* and has the IR focus issue. I've had it for 2 weeks from an authorized seller.
> *In -2EV of light my Rebel 550D was faster than the 5D3 (1/2s vs 1s)*. In 1EV of light the 5D3 is faster. The test was simple. Fully depress the shutter simultaneously on both bodies to see which shot first (images were in focus).
> 
> [The setups were different (5d3+600ex+70-200ii vs 550D+580ex2+24-70v1) but I found in previous tests that combinations of lens and flash did not make a difference to the outcome. Subject was a uniform tiled wall at 8 feet.]



By themselves, these data do not concern me greatly -- a 1/2 sec penalty for the extraordinary AF accuracy of the 5D3 seems reasonable at first. and thanks for being specific about the light level! But -- with the AF assist beam active, the AF systems are seeing greater than -2EV of light especially *since both beams were active at the same time!* So to me this is describing a marriage problem between the 5D3 AF system and the assist beam. The fact that the 5D3 focus lock time improves with an increase in light suggests that it is not even looking at (or isn't making very good use of) the assist beam. 

now then, take off the flash and force both cameras to focus in -2EV (and other levels of) light. how do they perform?

take both cameras into a closet and close the door ("pitch dark") both cameras should utilize the AF assist beam and should take photos, when tested separately (don't let both assist beams fire simultaneously)


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## ScottyP (Dec 18, 2012)

dlleno said:


> DeckardSolo said:
> 
> 
> > My serial is *xxxxx4xx5xxx* and has the IR focus issue. I've had it for 2 weeks from an authorized seller.
> ...



Try it with Yonguo 565ex and see if the beefier af beam helps.


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## AudioGlenn (Dec 23, 2012)

I don't think I understand the issue.

With the AF beam on, I can achieve focus in practically no light. Without the AF beam, my camera won't lock focus at all in the same dark room. Are people complaining about the speed of their AF with the AF beam? or the speed of the AF with the AF beam compared to the 5d mk2?


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## Chris Burch (Dec 24, 2012)

It's the amount of time it takes to lock focus when using the AF beam in low light. Pretty much everyone agrees the focus is spot on when it locks, but it takes considerably longer than it did with the 5DII.


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## AudioGlenn (Dec 24, 2012)

so according to those numbers, the mk2 was taking about 1.5 sec/shot (45 sec/30 shots), and the mk3 was taking 2.33 sec/shot.

Noticeable difference but I'm not sure what the fuss is about. I'm coming from a 60D though so maybe you guys noticed that .83 second difference much more coming from a mk2.


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## Louis (Dec 24, 2012)

"not sure what the fuss is about" it really is something to worry about when your working with the camera, You have a time limit to deliver photographs and you cant take the shot you need because of this, also there are not allot of golden opportunities to grab a great shot all the time, so you need fast AF when the moment arrives, 

this is a problem and Im so hoping the 5D3 gets a load of Love this 2013


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## AudioGlenn (Dec 24, 2012)

I am talking about "working" with the camera... I shoot weddings, kids, candid moments, shows... for money most of the time. 

I understand that speed is an issue and you want the camera to be as fast as possible. It just seems there's a bit of an uproar over the issue but the difference in time is less than 1 second (at least for this test). I'm not trying to say there isn't an issue or that we shouldn't have a camera that's at least as fast as the mk2 for the money paid for the mk3. It just sounds like some users need to check their settings and play with the "focus priority/release priority" settings. 

@Mike (OP), by chance, did you or can you try running the tests with different settings under the AF2 Menu for both 1st and 2nd shots, as well as the AF3 Menu under one-shot AF release priority?


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## MichaelTheMaven (Dec 25, 2012)

Just an update on the tests. I've done tons more with different speed lites, targets, etc, most of this has been 6D vs D600 type stuff. Ive even recorded video of how I do the tests so you guys can see and I will post the video here when it is done. 

*I am not seeing any difference between the 600 or 580 Speedlites*. I did look into the auto focus settings on the 5Diii, but as another forum reader pointed out, most of it has to do with AI Servo type shots (which doesnt require a focus lock) to take the shot. 

I should probably add a note, as I did on the Canon Forum about why I am going back and forth between the 2 differnent targets at different distances; Target 1 serves mainly to defocus. If im just aiming at target 2 and focusing over and over, its not a good measurement of the cameras ability to get that initial focus. 

Another point is that the average focus times for each shot work out to:

5Dii - 1.5s
6D - 1.7s
5Diii- 2.33s

But this is *not* what is happening. The focus lock on Target 1 (in good light) is always very quick, almost instantaneous. 

Focusing on Target 2 is taking longer than these average times. In fact, most of the time is spent on Target 2. 

It is hard to be precise, but I would say the times are closer to:

5Dii - 2.2s
6D- 2.5s
5Diii - 3 + s

I have a Sekonic 558 Light Meter that seems to be unable to measure the light Im shooting in which would be ideal to know, and am waiting on my new meter - that should help to know exactly at what point it starts to struggle. 

M


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## ScottyP (Dec 25, 2012)

MichaelTheMaven said:


> Just an update on the tests. I've done tons more with different speed lites, targets, etc, most of this has been 6D vs D600 type stuff. Ive even recorded video of how I do the tests so you guys can see and I will post the video here when it is done.
> 
> *I am not seeing any difference between the 600 or 580 Speedlites*. I did look into the auto focus settings on the 5Diii, but as another forum reader pointed out, most of it has to do with AI Servo type shots (which doesnt require a focus lock) to take the shot.
> 
> ...



Very interesting and very topical stuff Michael. A lot of people are very interested to see what you are doing and really appreciate your efforts.

I think the "two targets" idea is very solid thinking. My only "helpful suggestion" would be to not make one of your 2 focus points be in good light. I think it basically gives the cameras a big boost to their average focus time in bad light. I am sure the 5D3 is super fast in good light, but I think the question is how slow is it in bad light? I would be interested to see the same tests done with two targets, but with both targets being in bad light (none in good light). I think you would see a much more dramatic difference between the cameras if indeed 5d3 struggles in low light AF while 5d2 (or 6D) would not have. THAT would make a real statement.


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## Bennymiata (Dec 29, 2012)

I use my 5D3 for weddings, receptions etc, and mostly with a 580EXII and find the auto focussing almost instantaneous - and very accurate, with only about 4 out of 600 shots being soft (and those are probably because of me and not the camera), even ln very low-light situations.
I've never measured the time it takes to aquire focus in thousanths of a second, but it's plenty quick enough for me.


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## zim (Dec 29, 2012)

ScottyP said:


> I would be interested to see the same tests done with two targets, but with both targets being in bad light (none in good light).



+1 I'd really like to see those numbers


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## risc32 (Dec 29, 2012)

So it's looking like my thought that now that the 5d has gotten 1D level AF, it gained 1D level AF problems. All of these numbers look like what I would have guessed from my hands on use with this stuff.


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## Chris Burch (Dec 31, 2012)

Has anyone sent their 5DIII into CPS for repair based on the slow focus lock? Clearly some people don't have the problem (or they just haven't noticed), so it's a case of build quality. If enough people start doing it, perhaps Canon will be forced to at least acknowledge the problem.


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## AudioGlenn (Jan 21, 2013)

This is a copy of my post from another thread on the same topic:

So I've been doing some further testing. I can create a situation on my mk3 and 600 ex-rt where I can notice a much less snappy AF lock. I was not able to re-create the lag when trying to focus in a very dark (almost black) setting. Maybe, that's where I messed up in my prior testing. Maybe a completely black environment creates enough contrast between the environment and the red focus assist beam to allow focus whereas a dimly lit situation is lit just enough to give the camera trouble focusing because it can't really see the red AF assist beam as well.

I'm able to notice a significant lag when the ambient light is dim (proper exposure in camera at f/2.8, 1/50, ISO 5000). 

Seems to me like I would just turn the beam OFF when I notice the ambient light is about at this level. Am I still over simplifying the issue? I get that pros need their focus to be snappy to catch those moments. Wouldn't that mean a few test shots in the environment first to gauge the settings required....including wether or not to turn the AF assist beam on/off?

Maybe I don't understand the depth of the issue because I'm not coming from a 5D mk2 where the focus is supposed to be faster. That said, I'm an engineer by trade. We are trouble shooters by nature. It seems like there's a pretty easy fix for this (just based off of what I've been able to test). If this really is an issue for a shooter, just turn the beam off when you feel like it's slowing you down. Does ambient light in a reception hall or your venues change constantly for you guys? Isn't this just a matter of your experience telling you how your camera should be set to capture moments? I'm not trying to be condescending. promise. I still don't understand what the big deal is.


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## steliosk (Jan 21, 2013)

its very simple

5D2 focuses faster with af assist beam while 5D3 doesn't
same thing in 6D in 1Dx and all the new aps-c cameras

In low light situations where there is not enough ambient light for the focus point to find target AF beam is a saviour and canon screwed that up with their new cameras..
That costs moments and costs money and if you're shooting an event, people are filled with worries like "did he get the picture or is he still focusing?"

i shoot weddings too and light is a pain in the ass sometimes


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## AudioGlenn (Jan 21, 2013)

thats probably the most sense any one has made about it. Thank you.... so there is a grey area where you really need the AF assist beam to focus and can't do it with just ambient light. got it


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## dlleno (Feb 5, 2013)

Canon has made an important annoncement on this topic:

http://forums.usa.canon.com/t5/EOS/5D3-AF-assist-beam-slower-focus/m-p/13547/highlight/false#M1486


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