Canon 60d/430EX II and Flash indoors

[kasperoff]

Hoping someone could clear a few things up for me.

Firstly, why does my flash always seem to stick to ISO 400 when I use my flash indoors in Av mode and auto ISO?

Secondly, I'm getting shutter times of 1 second and over @ F2.8 in Av mode when shooting with the flash in admittedly pretty rubbish light.

If I set the camera to Tv mode and dial in 30 m/s the aperture value (2.8) flashes telling me their is not enough light for the shot, but it does a decent job of the exposure.

Also, just tried manual with the aperture at 4.5 shutter at 30 m/s and the ISO at 200 and got a decent exposure (perhaps very slightly on the dark side).

I'd expect to be able to get much faster than around 1 second in Av mode at 2.8 to be honest. Is there something I'm missing?

Lens is Canon 17-55 2.8.

Cheers.

 

[Gazamonk]

The 1 second exposure is correct for the ambient light. AV mode does not automatically set the shutter speed to say 1/60th second for flash and then expose the shot by taking control of the flash exposure. AV is a creative mode like manual and TV, i.e. you select the aperture and the camera sets the shutter speed for the ambient light. All other settings are down to the user. You can force the shutter speed up to a maximum of 1/250th second when using flash via the custom menu function however and the flash will do its best to get it right. If you want the camera to give you a best guess flash exposure in all lighting conditions with a faster shutter speed ( I suspect this is what yo were expecting earlier) then you should shoot in the appropriate scene mode (portrait for example) or just use P (program) which will set the shutter to 1/60th when the flash is popped up or an external flash is used.

There are lots of creative settings available in the 60Ds flash modes via the menu custom functions and you should read your manual thoroughly to get the best out of it. I suspect a large number of users quickly glance through the manuals or just use the quick guides but really to get the best from a modern SLR you really need to put in the time to learn the Camera. I can see from your post that you are not fully conversant with the correlation between aperture/shutter speed/light/exposure. Use these forums and in particular the tutorial sections and get the basics of light and exposure till it becomes second nature. That's what the forums and members community are here for. Your camera and lens are working as they should be so don't be concerned about your gear.

PS Oh and take your camera off auto ISO, AV mode defaults to 400 when using flash.

Let us know how you get on.

 

[Calzor Suzay]

This is worth an online read.
This is worth purchasing

 

[kasperoff]

Thanks guys that online guide looks really helpful. The manuals are OK, but a little cold. Hop to shoot a bit next week. On of my 12 week old twins has been ill, so had my hands full over the past week.

 

[ohara]

Calzor Suzay's first link is fantastic reading. I always try to use M mode when using flash (not manual on the flash though!) so I get the results I want. When using Av/Tv modes with flash the camera can change the way it behaves depending on how much ambient light there is.

Basically if you shoot in Av or Tv mode with flash they will always try to expose the background correctly and use the flash as fill light to expose the subject correctly. If this means using a long shutter speed in Av mode (slow sync) or going wide open aperture in Tv mode then it will do so. If you get a flashing shutter speed in the display in Av mode or a flashing F number in the display in Tv mode then it is the camera telling you it will not b able to expose the background correctly. You need to either slow your shutter speed down, open your aperture up, or increase the ISO.

In P mode the camera will try to expose the background and the subject correctly, but if there's not enough ambient light available then it sacrifices the background exposure in order to ensure the subject is correct. The camera will not go slower than 1/60 shutter speed (or faster than your X-sync speed unless you have high speed sync enabled). This could mean you end up with a completely dark/underexposed background, but the subject should always be correctly exposed.

M mode is the only real way to get exactly what you want when using flash. YOU set up the exposure for the background, and the flash exposes the subject. The camera will not interfere with how you expose the background, it will only change the flash's output to match your shutter speed.

When I'm shooting with flash, unless I don't care about the background, I always use M mode, manual ISO and manual white balance. If I just want to get a shot in the dark and I don't care about the background being exposed at all, I use either P mode or Av with the custom function which forces the camera to X-sync speed.