Shutter Priority

[wadooz]

Hi Gang, I'm still coming to grips with my 450D, hope someone explain something to me.
I'm shooting indoors and I've set my camera to AV and opened the shutter to F5.6 with auto exposure and flash selected, my camera sets the shutter time to 2 seconds? The photo comes out crap as you'd expect when hand held at that speed. Yet if I set the dial to full auto, then check what settings my camera chose, I find it's the same F5.6 but the shutter speed is 1/60 of a second and the photo is fine. My camera chose both settings but its right in full auto but very wrong in AV. Do I have a faulty camera?

[Cathus]

I'd guess that the camera on AV is metering for the whole scene & treating the flash as fill-in, therefore it selects a long shutter speed for 5.6 as if there was no flash to get a reasonable exposure & then adds the flash to fill in. i.e. if you turned off the flash you'd still get 2 seconds.

Try metering in partial or centre weighted which should bring the exposure time down, but even then the shutter speed may be too slow. Then you'll need to go to manual mode, select your aperture & a shutter speed of 1/200 or 1/125 or 1/60 & see how you get on.

[ap4a]

What ISO is your camera choosing for you?

Exposure is a combination of 3 values - aperture, shutter speed and iso, you need to factor all 3 into your settings.

[amk1977]

Originally Posted by wadooz

Hi Gang, I'm still coming to grips with my 450D, hope someone explain something to me.
I'm shooting indoors and I've set my camera to AV and opened the shutter to F5.6 with auto exposure and flash selected, my camera sets the shutter time to 2 seconds? The photo comes out crap as you'd expect when hand held at that speed. Yet if I set the dial to full auto, then check what settings my camera chose, I find it's the same F5.6 but the shutter speed is 1/60 of a second and the photo is fine. My camera chose both settings but its right in full auto but very wrong in AV. Do I have a faulty camera?

Hi Wadooz,

Does the flash pop up and fire in AV mode or is it disabled? If it doesn't pop up and fire, that would explain the slow shutter speed. If it does pop up and fire, the only thing I can think of is that the sync speed has been custom set to 2 seconds. Check your settings in the camera for the flash sync in the menu and set it for the highest value (probably 1/60). Full auto presumably takes no notice of the custom settings and is why it set to its default of 1/60 sec sync speed.

That's the only thing I can think of for causing the slow shutter speed when the flash is engaged.

Let us know how you get on.

[AndyStevens]

Full auto may include auto ISO too - the camera could be significantly increasing the ISO to give you a decent shutter speed. Would need to read the manual for a 450D - but I don't read my own manual

[amk1977]

What self respecting male does read the manual Andy? Its like flat pack furniture. Women read the instructions. Us chaps just put it together and have spare parts left over.... we don't need no stinking manuals!!!!

[chris-p]

Originally Posted by wadooz

Hi Gang, I'm still coming to grips with my 450D, hope someone explain something to me.
I'm shooting indoors and I've set my camera to AV and opened the shutter to F5.6 with auto exposure and flash selected, my camera sets the shutter time to 2 seconds? The photo comes out crap as you'd expect when hand held at that speed. Yet if I set the dial to full auto, then check what settings my camera chose, I find it's the same F5.6 but the shutter speed is 1/60 of a second and the photo is fine. My camera chose both settings but its right in full auto but very wrong in AV. Do I have a faulty camera?

It's partly the auto ISO. It's a 7 stop difference (1/60 to 2 seconds) and the 450D won't go 7 stops from ISO100 (ISO12,800). Also, the auto ISO mode on that camera won't go above ISO400 so there must be more to it. It's also likely that the camera is upping the flash compensation to help.

As was mentioned above, it could also be a metering thing - full auto mode will use the fully evaluative metering mode so it could be worth checking that.

Also, you're post is confusing... You titled it shutter priority but you're talking about aperture priority. Then you say you set the shutter to f/5.6. That's the aperture, not the shutter speed.

Finally, no you don't have a faulty camera. You're not looking at all the settings in auto mode. You need to check everything not just the aperture and shutter speed...

[AndyStevens]

@amk1977, that's a fine effort linking flat pack furniture and photographic equipment into the same sentence

Glad I'm not the only one with a pile of leftover screws/bolts and some pristine camera manuals

cheers
Andy

[cosmicma]

you need to check your flash sync settings are not set to auto for AV mode in the menu / function menu ( can't remember which one ) that would cause what you are experiencing

good luck...

[karenoliver]

Originally Posted by amk1977

What self respecting male does read the manual Andy? Its like flat pack furniture. Women read the instructions. Us chaps just put it together and have spare parts left over.... we don't need no stinking manuals!!!!

No!!!! Slaps amk lol I never read the camera manual either and I am a woman! I also built my own computer from scratch and know how to wire a plug lol


Karen