5D3 + AF assist beam = slower focus

[Carerra911]

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

[dll1477]

If I may summarize what I have read here, as a semi-professional photographer on the brink of making a 5D mark 3 purchase because of its marketed low-light capabillities:

To Mike,

I'm sure you are busy and don't have a lot of time to spend on the forums, but what ever you can contribute is greatly appreciated. There is a growing concern among 5D mark 3 owners regarding the AF performance, especially in low light situations and when using the Speedlight AF assist beam.  Discussion on this issue is very active over on the canonrumors.com site and a great many are posting here as well to try and engage Canon in the discussion.

if there is anything you can do to shed greater light on this topic that would be wonderful.   I think folks are restless for some answers or at least information to understand how the 5D mark iii works and how to work around this particular issue.  As you can imagine, these are photographers who have made a sizable investment, many of which are professionals in the 5D mark iii  target demographic -- wedding/event photographers.  They want the camera to fulfill the capabilities for which it has been marketed, and to excel in the areas that differentiate it from the competition (low light). 

Please share any additional information that you can, as is will be most enthusiastically received. thank-you for your time.

dll1477 

[echelonphoto]

What I really don't understand is how a major company like Canon would not do extensive field testing on their cameras

before release via the very professionals who will eventually use these products. This issue would come to light  immediately. I noticed it the first time out on the job....it was very obvious...not a subtle thing...and certainly not attributable

to user error or ignorance.

[GIlmorePhoto]

I think we just did the field testing. Now we need the fix/adjustment based on the observed results.  I'm hoping they realize that these observations are coming from largely from experienced photogs and not newbies where user-error may play a role.  As for experienced users, I think it's fair to say that we are willing to learn and adapt our techniques where viable, but when something just plum doesn't work in the intended fashion, we have a legitimate gripe.

[dll1477]

interesting specific use case suggested over at canonrumors.  present very detailed test scenario including camera body comparisons, and ask  Canon to verify performance to specifications.  Mike we need you to weigh in!

[marcdegroot]

if canon are reading this, id like to make a sugestion.

theres a setting in the af section called "one shot af release prior." it has 2 settings, release and focus. focus is the setting that takes too long to focus, release is just a waste of time as the photo is always out of focus, however it takes the photo really fast.

my sugestion would be to make 5 levels of this instead of 2 so the user can choose the level.

anyone else think this may be a good solution?

www.marcdegroot.co.uk

[starkyrulz]

its been terrible - 3k down on a camera and AF does not perform as it should at low loght cameras with Canon's own flash system. What was Canon thinking?

problem persists with Canon 5dmk3, 70-200is mkII and 50mm 1.4

[ChrisBurch]

I did a quick scan of the posts and I didn't see anyone mention that this problem also occurs on the 1DX.  I am a professional event shooter, so I am always trying to lock focus on subjects in dim situations and the added lag time for both the 5D3 and 1DX is absolutely unacceptable -- for a 1-series camera, it's almost unforgivable.

The lens I use most is the 24-70 f/2.8 and I have used both the original and new version with the same results.  For flash I use the 600 EX-rt.  For auto-focus, I usually use either zone (cluster or 9) or single point with expansion.  I've tried it with all points active, too, and that didn't seem to help.

One thing I have noticed is the 1DX (haven't tried this on the 5D3 yet) will fire before the AF illumination pops.  It seems that the camera grabs the initial focus, and then refines it before lighting up the focus point.  From what I can tell, the 1DX will fire after it gets the initial, which probably makes it as fast as I would want it to be, but I can't vouche for the accuracy of focus before it finishes refining.  I have the camera set to put the priority on focus instead of shutter release, so I'm surprised it fires before focus lock.

[echelonphoto]

Thanks for your input on the 1dx. I can tell you on the 5d3...if it fires before focus confirmation....it is usually soft

[zim]

+100 Well said sir but it is wrong that so many pros are having to rely on 'Mike' for progress. He may already be with the fishes for putting his head above the wall

[zim]

That's +100 to dll1477, didn't say in previous post