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

[echelonphoto]

I don't think its that simple....the af in low light isn't as great as they promote...so you still need af assist in those scenarios

and it just doesn't work on the 5d3 as well as it does on the mark2...I tried all options on my last evening outdoor shoot and

the camera just sucks.

[echelonphoto]

Digital....I did start a tread at FM forums....mostly it was denied and poo pooed by their posters....made me wonder if there

are variations among the bodies

[dll1477]

yes thats true there are two distinct problems:

1.  utilization of the AF-assist beam.  to the extent that the real problem is AF low light performance then perhaps #2 below is also important in this context, but my point here is that this particular test condition is easy to reproduce with great consistency, and there appears to be a marked lack of performance utilzing specific flash models, i.e 600 ex rt and 580 ex ii. 

2.  re:  FM forums and actual low light AF performance.  Yes, there is more variation here (RustyTheGeek returned his first 5D3 and the replacement worked better), and the tests exposed to date are all over the map without specifying the EV level, for example.  But yes, anectotally we have evidence (emperical at least) that the 5D3 accuracy comes at a penalty in terms of AF lock time in "low light" whatever that means to the user conducting the test.  Beyond the emperical and anectotal I have not seen a test constructed with repeatable consistency that shows "lesser" cameras performing better, i.e. under certain EV conditions within the specifications of both cameras, for example.

[digital]

echelonphoto. I also did this with a link to Canon Rumours about the subject. Here is the FM one. 

 http://www.fredmiranda.com/forum/topic/1168424/0#11141105

[Naomi]

Canon is listening, and we appreciate your comments.

We are still investigating and any updates will be shared as information becomes available.

Thanks for your feedback and participation in our forum.

[GIlmorePhoto]

Fantastic!  Thanks for letting us know.  (I'm happy to send in my gear if you need to evaluate it and confirm noted behavior.)

[dll1477]

outstanding,  Naomi; this is awesome.  you just calmed a great many folks.  thank-you!  just to know that Canon is listening is great encouragment I cannot tell you how much that is appreciated

[digital]

Yes. Outstanding. Thanks Canon.

[Carerra911]

Thank you Naomi  for your reply, Its nice to know you are there, Look forward to hearing from you and to getting a conclusion to the problem,

Louis

[glongstaff]

to be honest I have been thinking of purchasing a MKIII, coming from an old 350D....and reading issues like this and the 'light leakage' makes me worried and will be holding off until further news..