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No ignore that, I am not sure what that means. Take a look at each EXIF, the shutter, aperture and ISO are dead equal but I get two VERY different exposures.
ManuH said:
Alfisti said:
This makes ZERO sense (look at the EXIF). Any ideas?
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You found a 100m f/1.0 lens? Wow ;-)

Obviously an error or am I missing something?

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Manu



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Updated January '09
 
Better picture on the right, but what are we looking at?
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Regards Dean - Capturing Creation
 
Could it be outdoor brightness changes due to variable clouds? Is this something you're seeing regularly or is this your first discovery?
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DarylK
 
First time. I would buy that if the exposure changed as I was in Av mode not manual. With more light the camera should have used a faster shutter speed.
DarylK said:
Could it be outdoor brightness changes due to variable clouds? Is
this something you're seeing regularly or is this your first
discovery?
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DarylK
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Please visit my gallery at http://www.pbase.com/alfisti
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Updated January '09
 
2 mins apart & focal length change? Are you set on 1/3 or half stops, I reckon it's about 1/2 stop in which case no change with the heavier cloud.
Did you change lenses that would do it.
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Regards Dean - Capturing Creation
 
Alfisti said:
First time. I would buy that if the exposure changed as I was in Av
mode not manual. With more light the camera should have used a faster
shutter speed.
Click to expand...
If it's jpeg in-camera, it could be due to the processing. The pictures on the right seems to have slightly more contrast, not just a different exposure. According to PS there's a difference of about 2/3 EV between the 2 pictures. You could also check the WB, jpeg settings, etc.

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Manu



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What lens are you using? Different focal length with some zooms equals slightly different aperture. This is a linear thing rather than stepwise. The lens may tell that camera that it is f3.5 wide open at that length, but in reality it could be closer to f4 but it hasn't reached the transition point. My Sigma 17-70 says it is f3.5 at 28mm but it exposes brighter than that.

Try it without changing the focal length between shots and it should be the exact same exposure.

Lloyd

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The area photographed is slightly different in each photo. This will change the overall exposure value, less so in centre weighted but still a change. It could be the difference between being on one side of a set of exposure values or on the other side.

As another poster noted, there could also have been a change in the overall light levels.

The two photos were not taken under reproducable conditions, so it is not fair to judge them. Ideally the camera should ahve been tripod mounted, tripped with a remote, and ambient light levels checked to see that they did not change.

You also need to be aware that the bayer filter pattern over the sensor has twice as many green masks as it has masks for red and blue. This could also be a contributing issue in this case. Green is a difficult colour to capture correctly, especially when so much of it is the photo.

Regards

Chris Stone
 
It could also be a sticky aperture. If the aperture doesn't fully step closed before the shutter opens it can over expose. The other option as someone pointed out is a variable aperture zoom, and if it is overexposed at 100mm it will be slightly less exposed at 110mm (but the difference should be small).

The third possibility is you are using 2 different lenses, in which case contrast will be different between the two and based on the T-Stop of the lens or even the accuracy of the aperture opening you could get different exposures. My Tair 300mm f/4 underexposes by half a stop or more next to a modern DA 55-300mm that probably has much more efficient lens coatings that transmit more light.

Eric

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You used spot metering, first picture you metered of grass, second of the leaf.

Have you pressed AE lock and light changed? Have you linked AE lock with AF lock?
Could the in camera processing have used different black point?
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-Dominik
 
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