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Old Sep 17, 2010, 2:49 PM   #21
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Hercules - do you have the shot? Here's why. Assuming distance is short you should have plenty of flash power to properly illuminate a subject at 1/100 - but the devil is in the details. If you were 50 feet away and had aperture of f32 and ISO 100 - well, no, that wouldn't work well. Now, if you're saying you needed 1/5 so your camera metered at zero, that makes sense in many low light situations. You're not going to get it near zero, which is why you want to use flash. But I think it will be easier to help if we see a picture with the problem you're encountering.
Sorry john I don't have the picture, but if say you take a picture and the subject is in very low light, the exposure compensation on camera doesn't matter since your using flash right?
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Old Sep 17, 2010, 2:54 PM   #22
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Well, the answer is: It depends. What shooting mode are you in when you apply exposure compensation? Exposure compensation has to change SOMETHING - aperture, shutter speed, ISO. So changing it will change the mix of ambient light vs. flash. So it does have an affect in the same way changing Aperture, shutter speed or ISO in manual camera exposure changes the resulting photo. Does that make sense? But I'll be the first to admit, the concept of exposure compensation in manual mode (something no camera I have has, but I know some nikons do) makes no sense to me whatsoever - with or without flash.
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Old Sep 17, 2010, 2:56 PM   #23
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Well, the answer is: It depends. What shooting mode are you in when you apply exposure compensation? Exposure compensation has to change SOMETHING - aperture, shutter speed, ISO. So changing it will change the mix of ambient light vs. flash. So it does have an affect in the same way changing Aperture, shutter speed or ISO in manual camera exposure changes the resulting photo. Does that make sense? But I'll be the first to admit, the concept of exposure compensation in manual mode (something no camera I have has, but I know some nikons do) makes no sense to me whatsoever - with or without flash.
Ya it makes sense, but lets say your in manual mode on your camera like you say you should be in when using a flash?
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Old Sep 17, 2010, 2:59 PM   #24
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What camera are you using Hercules? None of my canon cameras allow exposure compensation when in manual mode. So, if a newer camera does - in order to answer your question I need to know what parameter gets changed when you apply EC when in manual mode.
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Old Sep 17, 2010, 3:01 PM   #25
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What camera are you using Hercules? None of my canon cameras allow exposure compensation when in manual mode. So, if a newer camera does - in order to answer your question I need to know what parameter gets changed when you apply EC when in manual mode.
John I have the canon 5D Mark II and when the exposure compensation is all the way to the left, I then start to adjust the shutter speed and it starts going towards the right.
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Old Sep 17, 2010, 3:15 PM   #26
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Hercules,
It sounds like you're talking about the camera's meter read-out in the viewfinder. That's not the same thing as Exposure Compensation. Let's say, for the sake of discussion, the ambient exposure is ISO 400, 1/30, f4. If you enter those values in your camera in manual exposure you'll see the tick mark on the meter at zero. Now turn to the left where there is (for the sake of argument) more light. Without changing the camera settings at all, you'll see the tick mark move to the right telling you the camera believes it is going to overexpose the image by X stops. Turn back to the original image and the meter changes again. So you're not applying EC, the camera is just telling you how far above/below what IT thinks the correct exposure is that you have chosen.

So in your case all that is happening is at the settings you dialed in, the camera says you're going to really underexpose this shot. As you adjust the shutter speed down, the camera is just telling you "you're getting warmer, getting warmer". The closer that tick mark gets to zero the more you're letting ambient light affect the exposure. Using flash with the camera's exposure tick at zero is tricky business - the camera is saying it doesn't need any extra light to expose properly so when it gets extra light from the flash you can get some flash burn. Usually you have to dial down flash output (with FEC) when you're using flash for fill in that capacity.

And, once that tick mark gets close to -1 you'll start to really see motion blur (ghosting).
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Old Sep 17, 2010, 3:19 PM   #27
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Hercules,
It sounds like you're talking about the camera's meter read-out in the viewfinder. That's not the same thing as Exposure Compensation. Let's say, for the sake of discussion, the ambient exposure is ISO 400, 1/30, f4. If you enter those values in your camera in manual exposure you'll see the tick mark on the meter at zero. Now turn to the left where there is (for the sake of argument) more light. Without changing the camera settings at all, you'll see the tick mark move to the right telling you the camera believes it is going to overexpose the image by X stops. Turn back to the original image and the meter changes again. So you're not applying EC, the camera is just telling you how far above/below what IT thinks the correct exposure is that you have chosen.

So in your case all that is happening is at the settings you dialed in, the camera says you're going to really underexpose this shot. As you adjust the shutter speed down, the camera is just telling you "you're getting warmer, getting warmer". The closer that tick mark gets to zero the more you're letting ambient light affect the exposure. Using flash with the camera's exposure tick at zero is tricky business - the camera is saying it doesn't need any extra light to expose properly so when it gets extra light from the flash you can get some flash burn. Usually you have to dial down flash output (with FEC) when you're using flash for fill in that capacity.

And, once that tick mark gets close to -1 you'll start to really see motion blur (ghosting).
That's exactly what I am talking about, I will try it out tonight thanks for your help
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