EX1: strange bracketing behaviour

I was trying the EV bracketing function and I noticed an odd thing; settings are:

• all Manual
• F1.8
• shutter 1/1500
• ISO 400

while two pictures are actually taken at 1/1500, the third one is taken at 1/350!

Why is that? Did you experience anythink like this?

for EX1 owners: could you please replicate my experiment and see if that's the same for you?

Thanks.

I get two pictures at 1/1500, third at 1/750 (- + EV.) Maybe since the max shutter speed is 1/1500, it takes 2 shots at that exposure since it can't get any quicker for the underexposed shot.

thanks for replying.

what delta did you choose for EV? I set the maximum distance and got 1/350

OK, yea if I set the max distance, I get 1/350 as well...

If you retry starting at 1/750, you get another 2 other exposures at 1/1500 and 1/180.

I have a feeling this is because you maxed out the shutter speed and it had no where else to go, so you get the 2 shots at the same exposure.

yes, that should be the reason; but I don't like very much this way of doing bracketing do you?

well, what would you suggest once you set the shutter speed at its max value? just curious... I guess it makes sense to me what is happening...

I'd like the camera to change the aperture value, rather than shutter speed...

tecnoworld said:

I'd like the camera to change the aperture value, rather than shutter speed...

Click to expand...

The answer to your wish is: select S Mode , Shutter priority.

I edited my old EV chart to the limits of EX1: apertures (running vertically) 1.8 to 7.1, and shutter speeds (running horizontally) 8 sec to 1/1600". Yes, I know the 1/1500 on EX1 is half stop faster than 1/1000 but didn't want to break this 1/3 stops chart for that difference.

Let's presume yuo want to utilize the maximum -2/+2 bracketing fully. In order to achieve this you have to select shutter speed that initially gives you aperture F3.5. The two bracketed alternatives were shot at F7.1 and F1.8, which are the limits of EX1 (zoom wide). If -1/+1 would be enough, then any shutter speed giving initial EV 0 aperture in F2.5...5.0 range would give you the desired alternative exposures.

On the other hand, if you would want to keep the aperture constant, here on the lower chart F1.8, then any shutter speed between 2 seconds to 1/320" would give you the maximum -2/+2 bracketing without being limited by EX1 shutter speed range.

As you see these values are based on ISO 80. Now you have some homework to figure out the values for higher ISOs.



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Markku
It's RAW or Never

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