Flash photog question.

[scraggles]

When I use the onboard flash, in AV mode for example, the camera adjusts the shutter speed accordingly to work faster with the flash, right?

When I use my 580EX, it doesn't. Is there some way to make it? I want to be able to use AV or Tv mode more with the flash, but the images tend to be at slower shutter speeds, or shallow DoF.

[Amorous]

580EX limits the camera shutter speed to 1/250 unless you select the high speed sync on the 580EX. Have you tried it? If not, press the button with flash icon & "H" (the one next to MODE on the right).

[coreypolis]

well there is a question in this, did you want flash fill or as the key light?

in av/tv, the camrea is still metering for ambient light, so the flash is just filling in, and the camera knows nothing about it, the flash controls the output. If you want a higher shutter speed, either use TV and set the shutter speed to 1/200 or less, or enable HSS, or use M (and the forementioned rules)

[PacAce]

When I use the onboard flash, in AV mode for example, the camera adjusts the shutter speed accordingly to work faster with the flash, right?

When I use my 580EX, it doesn't. Is there some way to make it? I want to be able to use AV or Tv mode more with the flash, but the images tend to be at slower shutter speeds, or shallow DoF.
The onboard flash does NOT do highspeed sync so there's no way you could have gotten a faster shutter speed than 1/200 or 1/250 with the flash turned on.

The 580EX, however, does do highspeed sync so with it turned on, the camera can use any shutter speed it needs, even the very fast ones.

[scraggles]

I'm confused. Right now I have my camea set up for a shot. The highspeed sync symbol is on the flash. AV mode, at f/6.3. When I push the shutter button halfway, the shutter speed shows up. It's showing up as 30" and apparently even then it's going to be underexposed. What the hell is going on? It's not pitch black in that room. I have a light on not even 10 feet away.

[tim]

Assuming the lens cap is off... ISO 100/F6.3 isn't very sensitive, and a single bulb doesn't put out much light. I'd be suprised if it said 30 seconds, but a number of seconds sounds right.

It sounds to me like you expect the camera to adjust the shutter speed just because you put a flash on - that's not how it works with an SLR. An SLR assumes you know what you're doing, rather than assuming you're stupid like compact cameras do. In Av mode the flash is fill, the camera still exposes for the ambient light. If you want to use the flash as the main light put the camera on manual mode, 1/200th, any aperture and ISO you like, put the flash on ETTL, and shoot.

[PacAce]

I'm confused. Right now I have my camea set up for a shot. The highspeed sync symbol is on the flash. AV mode, at f/6.3. When I push the shutter button halfway, the shutter speed shows up. It's showing up as 30" and apparently even then it's going to be underexposed. What the hell is going on? It's not pitch black in that room. I have a light on not even 10 feet away.
Move the camera towards the light. Does the shutter speed start to increase as you get closer to the light? If so, there's nothing wrong with your camera. You just don't have enough lighting in the room for a handheld shot. Put the camera on Manual mode instead of Av mode. Set the shutter speed to anything between 1/60 and 1/200 and use the flash as your main light source.

[scraggles]

Anyone who ever says photography is easy, should be shot. I suck at this. lol

[tim]

There's a fair bit to learn, it just takes time.