Autofocus problems in dark room

Ro-76

I have a question about autofocus in a darkened room for a kids play. Last time I did this (canon 600D sigma 17-50) using a light scoop to bounce flash off the ceiling, I found the camera was constantly struggling with autofocus. It would be constantly refocusing and getting it wrong half the time, and the flash would be firing to illuminate the scene each time to aid autofocus. The shots were well exposed with the flash setup, but out of focus.

Manual wouldn't work because I'm sitting a few rows back and couldn't be standing up long enough to manually focus properly and also the important part with the important child would have passed.

Doing the same thing next week in the same room but with my soon to arrive new 430ex I I. Any tips would be greatly appreciated.

Thx

5uspect

Autofocus in low light is always challenging. TBH manual focus is probably your best bet as you're going to be close to infinity at those focal lengths anyway.

With a flash you could shoot at f/8 at a highish ISO and get good sharp shots near infinity.

Of course remember to consider everyone else there when popping your flash

Ro-76

5uspect wrote: »

Autofocus in low light is always challenging. TBH manual focus is probably your best bet as you're going to be close to infinity at those focal lengths anyway.

With a flash you could shoot at f/8 at a highish ISO and get good sharp shots near infinity.

Of course remember to consider everyone else there when popping your flash

Thanks for the advice. It's actually a very small room, so I'll be a good bit closer to the action than that. I'll do a few trial runs beforehand to see if the flash helps with the autofocus.

frozenfrozen

Any way you could use a huge iso and wide aperture? That way you can snap away for as long as you want and you won't be filling the room with flash and potentially annoy the other people there... If not as said above, use a small aperture and full power on the flash and just manually focus to roughly where you think your subject is from you; and you'll get a sharp enough image. This way you'll only get one flash, instead of the autofocus assists too.

brightspark

Does the venue/school allow flash photography during the performance? Even if it is just a school performance, the flash can be very distracting to both the audience AND the performers.

Would you be happy if so someone else's flash distracted your child and made them miss a line? Or the parent in the row in front of you stands up blocking your view while your child performs?

Rant over.

If you really must get a perfectly focused and exposed photo perhaps you could ask to attend a dress rehearsal?

As others have said, you need to go manual during the performance, open up the aperture and push the ISO as far as possible.

Depending on the venue a seat at the back, with a long enough zoom, could be better allowing you to stand up for longer with less distraction to others.

twowheelsonly

Don't know about Canon but on Nikon cameras there's an auto-focus assist which sends a small focus assist light (red if you're using the external flash) once the camera is on Single Autofocus mode i.e. not on Manual or Continuous.

Brief video here giving a nice simple explanation, probably something similar available for Canon:

http://www.youtube.com/watch?v=7zt67UjXNWA

Gehad_JoyRider

you could pre focus in the room switch of said lights and click off manual focus and shoot away.