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Old Aug 4, 2007, 4:17 PM   #1
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I've been trying to take pictures in low light of bears feeding on berries along the side of the road. I'm shooting in manual, F11 but cannot get the camera to shoot faster than 1/80th. Of course all the pictures are dark and blurry.

I'm using the Canon 30D with the Canon 24-105 F4 or the Canon 70-200 F2.8. I have the Canon 580 flash.

All advice is greatly appreciated.

//jim
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Old Aug 4, 2007, 4:54 PM   #2
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killdeer0007 wrote:
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I've been trying to take pictures in low light of bears feeding on berries along the side of the road. I'm shooting in manual, F11 but cannot get the camera to shoot faster than 1/80th.
Are you sure you're using Manual Exposure (M on your mode dial)? What happens if you spin the control wheel for shutter speed on the camera? Are you saying you can't set it to anything faster than 1/80 second that way?

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Of course all the pictures are dark and blurry.
One doesn't necessarily have a thing to do with the other (shutter speed versus dark and blurry) .

Are you sure you're within the flash range?

With the aperture stopped down to f/11, your maximum range would be around 5 meters (or about 17 feet) at ISO 100 with a 580EX shooting straight on at max power (less if the light is diffused).

Range will be equal to the flash Guide Number (GN) divided by the Aperture at ISO 100. Then, each time you double the ISO speed, flash range increases about 1.4x.

So, by shooting at f/11, you decrease your flash range significantly (although you can bump up your ISO speed to try and compensate).

Shutter speed has no bearing on the amount of light from the flash your camera sees (unless you try to use a shutter speed that's faster than the sync speed). That's because the flash burst is very short (usually around 1/1000 to 1/10000 second).

So, as long as you don't have enough ambient light to expose your subject, as in shooting at smaller apertures (higher f/stop numbers) at lower ISO speeds in darker conditions, the flash itself can freeze the action (again, because the flash burst is very short, and the subject would only be properly exposed during the short flash burst).

Something doesn't sound right (not that shutter speed impacts the amount of light seen from the flash anyway). If it did, you'd need slower shutter speeds to get a brighter image if everything else remained the same. ;-)

But, are you sure you're using manual exposure and spinning the wheel that controls shutter speed and it won't go faster than 1/80 second?

If so (you are using Manual Exposure and spinning the control wheel that controls shutter speed to set it), perhaps some of our Canon shooters know what may be causing it (settings issue, etc.).


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Old Aug 4, 2007, 5:49 PM   #3
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You may want to post a sample with EXIF that members could look at to try and figure out the problems you're having.

My best guess is that you're outside of the flash range if you're getting images that are too dark, and you may need to open up your aperture some (smaller f/stop number) and/or use a higher ISO speed to get more range. But, I'm not Canon shooter and it could be a simple settings issue impacting your results.

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Old Aug 4, 2007, 6:29 PM   #4
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Thanks Jim

I think my mistake was backing of the shutter speed because the pictures looked dark. I've been practicing in the shade this afternoon and realized I should have been bumping up the shutter speed. I'm going out west tomorrow to look for the bears and I'll try some different settings. I'll post some pictures tomorrow.

Thanks for your advice!

//jim
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Old Aug 4, 2007, 6:38 PM   #5
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Again, I'm just speculating without seeing an image. But, from the problem description, it sounds like you were probably outside of the flash range for the aperture and ISO speed used (which would cause the photos to be too dark unless you used settings designed for ambient light exposure).

If that's the case (outside of flash range for settings used), either opening up the Aperture (use a smaller f/stop number) or using a higher ISO speed should help out (each time you double the ISO speed, flash range increases by about 1.4x)

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Old Aug 4, 2007, 7:13 PM   #6
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I'll try out the different settings in the backyard tonight before I head to the mountains in the morning.

Thanks!

//jim
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