shooting in Av mode, why the long exposures.. help!

[Captain Mantastic]

well i am not shooting in auto mode anymore and am learning the other modes ( i know, pathetic newb)

i have been having trouble with long exposures when in Av mode. If i take a shot in auto, and then go to manual and match the aperature and iso, why do i not have the same exposure? it keeps leaving the shutter open an dhence, my pictures are blurry. This is even with using the 430ex.

i have taken tons of shots just trying out different setting and can't seem to get it to work right.

sorry, i know i feel like an idiot.

thanks in advance

[Mark_Cohran]

When shooting in Av mode, the camera keeps sets the shutter speed to provide the proper exposure for the aperture and ISO combination your picked. When you attach the flash, the camera still exposes for the ambient lighting, and the flash just provides fill flash for the subject. Av mode is not manual mode - it is an auto mode (it's just not full auto).

There are a number of sticky threads at the top of the Small Flash and Studio lighting forum that you'll find useful.

Manual mode means putting your camera in M and setting the shutter speed, aperture and ISO yourself. The flash will then put out enough light to properly exposure your subject based on your aperture and ISO setting. If you want to add more ambient light (more exposure for the background), you'll decrease your shutter speed.

Mark

[Captain Mantastic]

Thanks Mark.

So I guess you are suggesting that i shoot in Manual mode then?

[Mark_Cohran]

Thanks Mark.

So I guess you are suggesting that i shoot in Manual mode then?

For indoor flash photography, yes, that's my suggestion or use Av or Tv and be aware of the limitations I've described above.

Mark

[Captain Mantastic]

For indoor flash photography, yes, that's my suggestion or use Av or Tv and be aware of the limitations I've described above.

Mark


well i guess then i go manual. most of the pictures i shoot indoors are of the pets and my neices and nephews, and they don't sit still for long enough to use a tripod or an extended exposure of any kind. so it is either green box mode (or one of the the other auto modes) or manual mode. hmph. guess i am a newb. thanks again!

[Mark_Cohran]

Everyone is a newb at some point -- and the members here are most helpful.

In the meantime, this thread is a must read for anyone using EOS flash: http://photonotes.org/articles/eos-flash/

Good luck,

Mark

[Curtis N]

Captain,

The link Mark gave you is an excellent guide. Flash Photography 101 (link in my signature) might give you a good start, too.