topic Re: 5D3 + AF assist beam = slower focus in EOS DSLR & Mirrorless Cameras

5D3 + AF assist beam = slower focus

Carerra911 — Tue, 05 Feb 2013 23:40:29 GMT

Hello All,

While I am new on these forums I have been on the Canon Rumors Forums for a few years now,

I really wanted to bring this too the attention of you and Canon as it is simply a highly important problem, those of you that don't know, the 5D3 suffers serious focus locking issues when a Canon speedite is attached in Low light, the AF assist beam causes lag with the AF from the 5D3, this makes it virtually impossible to achieve focus in low light when the speedlite is attached, I wanted to bring the topic to this forum, so I have pasted a link to all the discussion we have already had about this problem at Canon Rumors.com - see below

http://www.canonrumors.com/forum/index.php?topic=10275.0

Please help in letting Canon know this is a very serious problem and effects the cameras performance in most working environments when a speedlite is attached and working in low light, conferences, nightclub work, weddings etc, and can stop the photographer completing the job or task.

Regards

Louis

Re: 5D3 + AF assist beam = slower focus

Steve_urwin — Fri, 16 Nov 2012 16:35:08 GMT

I very much verify this is a serious problem.

I often find myself reverting back to my 7D.

Please find time to have a look into a fix

Thank you

Re: 5D3 + AF assist beam = slower focus

jfo — Fri, 16 Nov 2012 20:41:55 GMT

Wow! I totally didn't know this was a widespread issue and an actual technical problem; I thought it was just me and having the wrong expectations.

I will be following this thread with great interest.

Re: 5D3 + AF assist beam = slower focus

Carerra911 — Fri, 16 Nov 2012 22:11:52 GMT

Thanks please try and make this issue known, I just know people will try and hide this!

Re: 5D3 + AF assist beam = slower focus

hambergler — Fri, 16 Nov 2012 22:33:50 GMT

It is also documented here: http://forums.usa.canon.com/t5/Speedlites/Canon-600EX-RT/m-p/951#U951

I havea 5DIII and 600ex-rt and i've noticed it does this too.

Various complaints can be found if you just google it and I believe Canon has refused to acknowledge any issue yet.

Re: 5D3 + AF assist beam = slower focus

Marsu42 — Sat, 17 Nov 2012 10:07:51 GMT

@hambergler wrote:
Various complaints can be found if you just google it and I believe Canon has refused to acknowledge any issue yet.

I hope Canon cps does acknowledge this issue soon and what determines what exact situations and camera settings trigger it, even if they are unable to do anything about the low light af problem and the af assist beam lag. The cause supposedly is that the smaller af points of the 5d3/1dx simply have trouble in these situations, the fix is the larger af point design of the 6d.

The irritation about this issue is due to the fact that obviously many people thought it's somehow their own fault (and with most other problems, it probably is) and not a potential regression in the af design in comparison to the older 5d2 or 7d/60d-like design.

Re: 5D3 + AF assist beam = slower focus

canonshooter — Mon, 19 Nov 2012 21:52:27 GMT

I would also like to add my name to this issue. Having come from a 40D to a 7D and now a 5D3, I can say the camera is tremendous, EXCEPT for the slow focus with assist beam. AND I use center point as my main focus point 90% of the time and recompose. Now, try and find that very "thin-lined" focus square in low light or against a dark object. Very hard to do! And when you achieve focus you shoot with a leap of faith that you guessed the focus square location correctly. With the 40D and 7D you could see the focus square blink and didn't need the focus confirmatio dot in the viewfinder or the beep.

I would give up a whole bunch of focus squares, if I could just find the one I have selected. Is this a light leak issue? Just be straight with us and tell us if it can be fixed and when.

Thank you.

Re: 5D3 + AF assist beam = slower focus

Mykolas — Tue, 27 Nov 2012 16:51:11 GMT

Hi Everyone,

Canon would like more detailed information from you regarding these issues:

1. What is the focal length being used for the affected shot? For example if the lens being used is a 24-70, what was the focal length, at the time.

2. How far was the subject from the camera?

3. Which AF point(s) were active?

Thanks for your assistance!

Re: 5D3 + AF assist beam = slower focus

mwh1964 — Tue, 27 Nov 2012 18:49:28 GMT

1) Have the problem at all focal lengths on 24-105.

2) I find it doesn't matter

3) Single point as well as full auto

Re: 5D3 + AF assist beam = slower focus

jaayres20 — Tue, 27 Nov 2012 19:01:22 GMT

I am a wedding photographer and I started the topic over at Canon Rumors. I find that the 70-200 f/2.8L IS II gives me the most issues with the AF assit beam. I have shot over 20 wedding with the 5D3 and I noticed the issue right away. The AF assist was a big help when I had the 5D2 but once it is enabled with the 5D3 it takes much longer to achieve focus. The focus beam will flash 3 full times before focus is confirmed. When I disable the AF assit beam and take the same picture at the same time it focuses instantly. I don't understand why the the AF assist beam hurts the focusing performance. Below is one of my posts from the Canon Rumors fourm the explains it a little more.

"For me the 70-200 f/2.8L IS II without the AF assist will focus in almost an instant even in very low light as long as there is an area of some kind of contrast. For example at wedding receptions when I am photographing the first dances as long as I can focus on where the white shirt meets the grooms neck then I am fine. I also feel really comfortable using AI servo to track the bride and groom entering a very dark reception (so dark I may not be able to see a lot with my own eyes). Again as long as there is some contrast where maybe the white vest meets the black jacket. Now that is great but what if I accidentally slip off an area of contrast and my focus point hits a the dark flat area of the tux? When that happens the lens hunts way out of focus and it takes me a few seconds to recover. In that time I may miss something I really need to get like a smile or a kiss on the cheek. I have tried expanding the point so the surrounding areas are active as well but I found that causes a lot more hunting. One point works the best for me. Now when I used to shoot with the 5D2 I seem to remember being able to focus anywhere because the AF assist would work and it didn't matter if I focused on an area of contrast. That is why I would like the AF assit to work better with the 5D3. When I use the 5D3 the AF assit lamp will flash 3 times usually before the focus will lock and blink red. Now most of the time it focuses much faster than the red confirmation but you really can't trust it all of the time. I would say 90% of the time that area will be in focus before the red confirmation but it may be the time you really need that it will be slightly out of focus. The AF assist flashing 3 full times before focus is way too long in my opinion especially since it was better than that in the past with the 5D2. There has to be a reason and I just want to know why. If there is a trade off because the AF points are smaller I can live with that and like I said before I have learned to work with what I have but part of me feels like I shouldn't have to."

Re: 5D3 + AF assist beam = slower focus

stipotle — Tue, 27 Nov 2012 19:11:19 GMT

Small sample size, but I definitely experienced this as well on a job. (5d3+580EXII)

I thought it was a personal learning curve situation at the time, but focus would hunt for 2, 3, 4 seconds and often not ever find a solution.

I was using primarily the 70-200mm f/2.8L IS II at all focal lengths

Subjects were anywhere from 10 feet to 40 feet away

Mostly Spot AF, and I believe occaisionally AF Expansion - 8 additional

Thank you.

Re: 5D3 + AF assist beam = slower focus

Carerra911 — Tue, 27 Nov 2012 19:21:51 GMT

I find I have the problem with the 3 lenses I have, I own a 24.1.4 II and a 50.1.4 and a 70-200 I L 2.8 and all lenses caursed the 5D3 to almost "hang" like it was just not doing anything, you can imagine witnessing this for the first time you start to sweat, " like whao what the hell is happening" I have just now tested the 5D3 with the 430EXII and can see that when I focus on anything that is darker, a black Bag etc, a darker toned object the 5d3 will only focus when the 430EXII has beamed atleast 3 times, I do believe the problem is not only with the 430EXII but with all other Canonspeedlites,

I can imagine from other people stating its worse with the 70-200 is because at lengh the beam is also weaker, when I first noticed the problem I was doing work at no more than 6 feet away.

It makes me think that the 2 units are not in sync with each other when in darker situations,

Re: 5D3 + AF assist beam = slower focus

Carerra911 — Tue, 27 Nov 2012 19:24:24 GMT

I would also like to add, i used Centre Point AF, then tried to use expanded points, nothing helped,

Re: 5D3 + AF assist beam = slower focus

greggbhill — Tue, 27 Nov 2012 21:30:09 GMT

same here on 5D3 with these lenses: 70-200 f2.8L II, 24-70 2.8L II, 35L, 50 1.4

happens occasionally with all lenses with 580EX II and 600EX RT.

For me it is always a low-light wedding reception. i'm usually 2-5 meters away from subjects.

i do have my shutter release priority to Focus.

when this happens, it is pretty embarassing.

waiting for the "oh, wow that takes long to focus... what kind of camera is that?"

hope this can be fixed soon!

Re: 5D3 + AF assist beam = slower focus

Memdroid — Wed, 28 Nov 2012 08:35:39 GMT

Problem is always present in near dark environments (nightclubs, dark wedding receptions), usually shooting people and the scene. AF Assist beam ON with the 580EXII and the 600EX

1. I primarily use the 24-70 L II. The problem arises above the 35mm range, very often at 70mm.

2. Distance to the subject is between 1 to 2 meters. The more the distance the more lag.

3. I always use Single Point AF at the center. Outer edges are noticable more lagging.

Mode : M

shutter: varieing betweeen 0.8-1/100 seconds, depending on the situation

F-number: 2.8-4.5

AWB

ISO 800-2500

One Shot AF

Evalutative meting

Re: 5D3 + AF assist beam = slower focus

digital — Wed, 28 Nov 2012 04:22:28 GMT

Jusy going to follow.

Re: 5D3 + AF assist beam = slower focus

digital — Wed, 28 Nov 2012 05:10:35 GMT

So I put my new 70-200 2.8 II on my 5D3 and tried out 600EX-RT and tried it out in a very dark room. Like Jaayres20 stated at times it would blink 3 times before AF lock. Other times was almost instant. Room was so dark it did not work at all without it.

Obsevations.

1. Wiggle room. The flash has a bit of play in the shoe. At 15 -20 feet if you move the flash to the left and then to the right there is a significant difference of where the vertical beams line up as compared to the center focus point.

2. The vertical beams are pretty wide at 15 - 20 feet.

3. It seems the AF assist is a bit weak in illumination for that distance but I'm not sure. I sold my 580's so I can't compare.

Seems to me the grid patterns in my 600 and not not sure about other flashes are not fine enough. Is the focus point being completely within strip of AF assist light (or not) causing this at times? I imagine that the whole idea of the patterns is to create contrast at the target. If the focus point is completely within the red strip does it still work? I'm not an engineer but my thought is somewhat, however weak illumination would be a hinderance as well.

I used to own a 5D2, 70-200 F4 IS and 580EX II and I don't recall this amount of lag. I have yet to field test the new gear. It is not horrible but definately not comfortable at this point.

Re: 5D3 + AF assist beam = slower focus

digital — Wed, 28 Nov 2012 05:20:36 GMT

So I tried my 600 and 70-200 2.8 on my 7D and in my opinion the lag time is about the same.

Re: 5D3 + AF assist beam = slower focus

marcdegroot — Wed, 28 Nov 2012 13:07:43 GMT

Im having the same problems. But i dont think its just an AF beam issue, my 5d3 is slow to focus in any low light situation.

As a festival/nightclub photographer, i bought the 5d3 to take advantage of the high iso along with the new af system. The 5d3 failed me. Im having to go back to the 5d2 which is amazing at focusing with low light and also using the af assist beams (ste2 transmitter and 580ii).

Im using it with these lenses

14mm 2.8L

15mm fisheye 2.8

35mm 1.4L

50mm 1.2L

85mm 1.2L

Ive experimented with the af settings in the menu and also with different focus points but still no joy.

This is extremely frustrating and totally unacceptable. How can Canon get something this important so wrong?

Marc

www.marcdegroot.co.uk

Re: 5D3 + AF assist beam = slower focus

paneraisti — Wed, 28 Nov 2012 17:55:25 GMT

Canon 1DX have same problam

slower focus in dark with 600EX-RT

35MM F1.4

50MM F1.2

85MM F1.8

all my lens are same problem

i think its new focus system bugs

compare with my 1D mark IV

it's very slower on focus

please fix the problam quickly ^^