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Rebel T6 exposure time in aperture priority mode with flash

Started Jul 4, 2019 | Questions thread
AnthonyL Veteran Member • Posts: 3,686
Re: Rebel T6 exposure time in aperture priority mode with flash
2

plantrob wrote:

I just received my new T6, to replace my old Olympus E500 that in sadly dying. I don't have any new lenses yet (was married to a fixed-zoom 50mm lens for my Olympus, I'll have to find an equivalentin the Canon line), but decided to see how I'd do with insect photography with the kit lens. I nearly always shoot in Av mode, so that's what I tried. I was working inside, so I activated the flash, and set F/6.3 as a starting point. Took the photo, and noticed a very long exposure time (1/3s). Tried a few more times, with same result. Then I decided to switch to Macro mode on the automatic dial, and found that a much more reasonable exposure time was selected in this case (1/160s), with about the same aperture (F/5.6) as I had selected, and same ISO (800), and flash automatically activated.

Not surprisingly, on inspection, the Av photos were not only blurry (I'm not that steady) but also overexposed. But I'm confused - why does the camera automatically select an appropriate exposure time in macro mode, but not in Av mode? If I want to use Av mode with flash, how do I get the camera to select a suitable exposure time?

Short answers:

1) Canon will expose for 'background' in Av mode and assume flash is "fill-flash", ie not the main illuminator

2) If you want the flash to be the main illuminator then set to manual mode with Shutter speed no faster than 1/200, aperture to suit DOF and let the flash work itself out. Slow down the shutter and/or increase the ISO if you want a more natural background

Longer answers:

Read the manual

Read https://www.dpreview.com/articles/1905744226/rebel-forum-faq and in particular "I can't get flash to do what I want"

Go to Canon's Digital Learning Centre to get the best out of your new camera

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