5D3 & 600ex-rt + AF assist beam = slower focus

[Shawn L]

With different people seeing different things with the same platform, I wonder if someone who has it working (on say a 5DIII or 1DX) would be okay with posting their camera's config file. Others could (after saving their own config to restore later) load the "working" config to see if it works on their camera, too.

That would at least eliminate/confirm it being a configuration issue.

Shawn L.

[neuroanatomist]

With different people seeing different things with the same platform, I wonder if someone who has it working (on say a 5DIII or 1DX) would be okay with posting their camera's config file.

Has to be a 1D X, right?  The 5DIII doesn't have the ability to save/load settings from a memory card.  If someone having this problem on a 1D X wants to try, PM me and I'll send you a .CSD file.

[Shawn L]

Has to be a 1D X, right?  The 5DIII doesn't have the ability to save/load settings from a memory card.  If someone having this problem on a 1D X wants to try, PM me and I'll send you a .CSD file.

I defer to you as I simply don't know

Shawn L.

[Caleb Luke]

Interesting read indeed. I have a few 600rt's and both bodies, I am going to test side-by-side to see if I can replicate.

[neuroanatomist]

Interesting read indeed. I have a few 600rt's and both bodies, I am going to test side-by-side to see if I can replicate.

Thanks!

[Marsu42]

Interesting read indeed. I have a few 600rt's and both bodies, I am going to test side-by-side to see if I can replicate.

... and please test some lens & af setting configurations in different lighting conditions and object distances if you have the time :-p - there is definitely some FUD about this issue but even considering that there are enough "serious" reports it cannot be dismissed as imaginary.

[kasperj]

This issue is a strange one..... I have tested a 5DIII (paired with a 24-70 MII) with the 600rt in a very dark indoor environment and found it to be equally fast (or slow) in acquiring and confirming focus on either single or multiple focus points with and without the aid of the assist beam.

I have one of the first produced 5DMIII's with the light leak (6th digit is 1)

[jaayres20]

This issue is a strange one..... I have tested a 5DIII (paired with a 24-70 MII) with the 600rt in a very dark indoor environment and found it to be equally fast (or slow) in acquiring and confirming focus on either single or multiple focus points with and without the aid of the assist beam.

I have one of the first produced 5DMIII's with the light leak (6th digit is 1)

Do you have any other lenses you could test?  My 70-200 f/2.8L IS II is the one that gives me issues.  My 24mm 1.4L does just about the same with or without the AF assist beam.  With the 70-200 there is a very noticeable difference.   

[kasperj]

I don't own the 70-200, but just tested again with a 16-35 II and a 85 1.2 II. If there is a difference I am not able to detect it. The focus acquisition with the 85 was perhaps even slower than normal with the focus beam, but not by a consistent margin.

I have only tested using the AF back button in single shot mode

[Area256]

I have a 60D and 580EX II, and I have the same problem (focus takes 2-3 seconds and often misses with AF assist).

Ok, now it's getting really strange - at least with my 60d and the 70-300L & 100L the camera near focuses instantly without hunting with the af assist beams of the 430ex2 and 600rt. It takes just a little longer than in good light because it beams, focuses, beams again and does the final focus. If your 60d hunts then there's definitely something wrong with your setup.

Found the problem (at least in my case). It turns out that my 580EX II has some wiggle room in the hot shoe, and was misaligned for interacting with my selected AF point.  I had to turn off all the lights in my room, and look really closely to see the issue.  Adjusting the flash a little in the shoe fixed the problem.  I wounder if maybe some of the users here are experiencing this same issue? 

Try going into a dark room, and focusing on a white wall, you should be able to see if the beam hits in the location of your selected AF point.  If not, there is a misalignment with your flash.   This could explain why some, but not all, members are seeing the problem on the 5D3.

[Mehmetski]

Distance is a major factor on the issue. Close distance focus won't show hardly any lag with the 5dII+Speedlite AF Assist combo. The issue start to show somewhere around 1.5 to 2  meters from the subject, get 0.5 meters further away and you'll see it consistently lagging.

If the subject is moving than the lag is almost unbearable. Spontaneous quick shots are near impossible. Even with the 24-70 II

[Marsu42]

If the subject is moving than the lag is almost unbearable. Spontaneous quick shots are near impossible. Even with the 24-70 II

Um, I don't believe it's in the product announcement that the 5d3 can track moving objects  far away in the dark with af assist? Though it should work on static objects in the 2m range, it certainly does on the 60d.

[Mehmetski]

If the subject is moving than the lag is almost unbearable. Spontaneous quick shots are near impossible. Even with the 24-70 II

Um, I don't believe it's in the product announcement that the 5d3 can track moving objects  far away in the dark with af assist? Though it should work on static objects in the 2m range, it certainly does on the 60d.

That's true. Just to avoid the confusion, the last sentence is more a general statement for the problem and not so much with the distance. With that said, I had no problems with this before with the 5DII or the 40D where even moving subjects were locked almost instantly with AF assist beam in the dark.

[echelonphoto]

OK....so many of us now know there is a REAL problem here.  How do we go about notifying Canon and getting
them to fix it.

[neuroanatomist]

OK....so many of us now know there is a REAL problem here.  How do we go about notifying Canon and getting
them to fix it.

Try to definitively document the issue.  Call them.

When there were only two of us discussing the 1D X AFMA bug, I called Canon, they'd never heard of the issue and couldn't replicate it. They asked me to send my camera in. Instead, I documented the problem with a video, and sent that to them.  More people called.  Less than a month later, a firmware update (v1.0.6) fixed the problem.