580EX exposures

I have always used my 580 EX with the camera on manual as I thought I got a better exposure. But noticed recently when using indoors where I just need a little extra light I seem to get better exposure with camera on "A" and the flash then does more of a fill flash. Is this because this indoor situation is similar to outdoor fill flash?? If I was indoors in low light would "M" work better.

Several months ago when I first got flash it seemed to work better with camera on Manual. Do you think the flash is failing or is this normal, and I have just had more low light situations so far??

When should I get more light from flash and a better overall exposure, with camera on "A" or "M"/

And of course in both cases the flash is on ETTL

If you use Av mode indoors and you like the results, that probably means that you had your ISO high enough and your aperture wide enough to expose the ambient light without an excessively long shutter speed.

If you want to mix indoor ambient and flash, and deal with the potential white balance issues that go along with mixing light sources, then Av mode can work fine. You'll just need to keep an eye on the shutter speed and adjust accordingly. This approach generally will create brighter backgrounds and more natural-looking light, except for the white balance issues previously mentioned.

You can also accomplish the same thing in Manual mode, using the same aperture, ISO and shutter speed settings.

In small rooms, you can usually bounce the flash off the ceiling and illuminate the whole room pretty well. In large rooms this is difficult to do, and using the ambient light can be beneficial.

It's always a compromise, since the slower shutter speeds, wider apertures and higher ISO settings required to expose the ambient light all can potentially reduce sharpness or image quality in their own way. You need to decide what's most important.

Curtis N wrote in post #2893671
If you use Av mode indoors and you like the results, that probably means that you had your ISO high enough and your aperture wide enough to expose the ambient light without an excessively long shutter speed.

If you want to mix indoor ambient and flash, and deal with the potential white balance issues that go along with mixing light sources, then Av mode can work fine. You'll just need to keep an eye on the shutter speed and adjust accordingly. This approach generally will create brighter backgrounds and more natural-looking light, except for the white balance issues previously mentioned.

You can also accomplish the same thing in Manual mode, using the same aperture, ISO and shutter speed settings.

In small rooms, you can usually bounce the flash off the ceiling and illuminate the whole room pretty well. In large rooms this is difficult to do, and using the ambient light can be beneficial.

It's always a compromise, since the slower shutter speeds, wider apertures and higher ISO settings required to expose the ambient light all can potentially reduce sharpness or image quality in their own way. You need to decide what's most important.

ISO was only 100, but the room did not need much additional lighting. Aperture was about 4 (wide open for 24-105L). I almost always keep the ISO at 100. In lower light situations with ISO of 100, do you find you get better overall results with camera on "M"

canon shooter wrote in post #2895783
ISO was only 100, but the room did not need much additional lighting. Aperture was about 4 (wide open for 24-105L). I almost always keep the ISO at 100. In lower light situations with ISO of 100, do you find you get better overall results with camera on "M"

I'm curious what your shutter speed was. Generally unless you're in a room with lots of big windows during the day, ISO 100 and f/4 won't be enough to get significant exposure of ambient light at shutter speeds fast enough to prevent motion blur.

When I'm using flash indoors, the first thing I decide is whether to rely on my flash for all of the light, or try to include some ambient. In residential/office/cla​ssroom environments, I usually use M mode, bounce the flash, set the shutter at flash sync speed, use the widest aperture I think I can get away with to provide enough DOF, and raise the ISO to ensure enough flash power. This might be ISO 100 & f/2.8, or ISO 800 & f/8, or anything in-between. It depends on the subject matter, distance, and room size.

If I'm including ambient light, I have used Av mode but usually use M. I would rather control the shutter speed to avoid motion blur problems. Having a nicely exposed background is useless if the subject is blurry. Typically I'll set the shutter speed around 1/60 and crank up the ISO as needed to get the metering needle just above -2.