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Z1u and auto exposure


Bob Hayes

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I was shooting with the Z1u over the weekend. Day exterior. Moving fast I put the expure on auto. The lighting was standard front lit. Auto expsure said on thing but the 70% iris said I should stop down a couple of stops. Why the discrepency.

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Sorry I don' get this sentence perfectly due to my bad english knowledge

Auto expsure said on thing but the 70% iris

 

But I've read topics on french forums about such problems with this camera...

 

Are you sure the zebras were set at 70 % ? They said on this forum that zebras should be set at 100 % on this camera. If someone set it to 100 % before you used it and you thought it was on 70 %... It might explain it ?

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I was shooting with the Z1u over the weekend. Day exterior. Moving fast I put the expure on auto. The lighting was standard front lit. Auto expsure said on thing but the 70% iris said I should stop down a couple of stops. Why the discrepency.

 

There may be a compensator which can adjust the auto-exposure up or down up to 2 stops (so if the AE thinks the scene should expose to f5.6, you can adjust it so if will expose that scene at f2.8 or f16 or somewhere in between). I have an XL-2 and it has that feature. The zebras don't have anything to do with the auto-exposure. They just tell you what in the frame is 70 IRE or above if you set them to 70.

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The zebras don't have anything to do with the auto-exposure

 

Sorry, I know they don't

 

It's because of that sentence (that I didn't understand well) That I thought Bob might have been using them in appreciating his exposure and that they might have confused him, eventually...

 

Auto expsure said on thing but the 70% iris
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My English isn't so good either. I was setting th exposure using auto iris and it doesn't agree at all with Zebra settings.

 

Were you checking it with a waveform monitor where the zebras were telling you 70 IRE and the waveform was telling you it was something else?

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  • 1 month later...

I became aware of the same discrepancy today as I was trying to figure ot me camera`s ASA. I imagined that the autoexposure would give me a reading which at the same time would present zebra at 70IRE. But the autoexposure reading was about one stop darker than the reading with zebra.

 

What I want is to use a lightmeter (on reflected mode) and to be able to determine how many foot lamberts my camera needs for any given subject to register 70IRE at a predetermined T stop.

 

I want to use a lightmeter in order to work apart from the camera and the LCD. However, I want to set my lights according to the IRE of the image. I am thinking of lighting to 70IRE and then checking if at 100IRE I get zebra stripes and then reduce light levels as required.

 

Please if anyone has a similar method, I'd appreciate your advice.

 

Thanks

 

 

LJ

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