Anyone had problems focussing a 5d2 in low light?

[Cris_L]

Last night i was at a wedding as a guest and I said I'd do some shots of the first dance as their photographer had gone. I was also going to do some shots during the reception. during the first dance and rest of the evening my 5D2 would not focus unless I managed to catch a bit of light to assist. I know the Af is not the best but it wasnt even THAT dark.

Anyone else had this problem and what's the best way forward?

 

[Kemble3]

I've never had this problem with mine, what lens were you using?

Ian

 

[cuthbert]

i think it depends which focus point you were using and how much contrast the thing you were focussing on has.

I find the centre point to be pretty good in all but the most dreary of scenes whilst the outer points do tend to be a bit iffy when there isn't much light or contrast.

were you using an f2.8 or faster lens, btw?

 

[Cris_L]

I was using a 24-105 f4 with centre focus point only. Cheers guys

 

[cuthbert]

f4... i think that might be your problem Cris. if you can, i'd give a f2.8 or faster lens a try and see if the problem is mitigated.

i don't own a lens slower than 2.8 so i can't go try it myself now to see what the results are but i'd be 99% sure that it's just at f4 there wasn't enough light for the AF to lock.

and anyway i can't think if a better reason to justify a new lens myself!

 

[Cris_L]

Also, I was spot metering...could that of been a factor?

 

[Musicman]

I'd go with f/4 being your problem.

I've had trouble focussing occasionally (in very dark conditions) with my 5D Mk1 and a 17-40 f/4L on when a faster lens will without issue.

 

[EOS_JD]

Also, I was spot metering...could that of been a factor?

Best to shoot in manual in those conditions (I guess the light would be consistent).

I use the f4L IS at weddings and not had any great issues. Usually the outer focus points are hit and miss but centre usually works ok.