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EV SCALE


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#1 Bruno Alzaga

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Posted 08 July 2009 - 07:14 AM

I´ve heard about the EV scale, it is in my new light meter, but i can not understand how it works and what purpuse it has.
If anyone can explain to me i would be very happy.

Thank you
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#2 Chris Keth

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Posted 09 July 2009 - 01:45 AM

I´ve heard about the EV scale, it is in my new light meter, but i can not understand how it works and what purpuse it has.
If anyone can explain to me i would be very happy.

Thank you


It's just a number to represent all combinations of aperture and shutter speed that yield the same exposure. For example, EV0 equates to f1 at 1 second of exposure. It also equates to f2 at 1/2 second exposure, f4 at 1/4 second, f8 at 1/8 second, etc.

I have never found much use for it, but it is a nice convenient way for lightmeters (this all started in the days of analog meters) to only have to output one number instead of two.
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#3 Bruno Alzaga

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Posted 09 July 2009 - 08:09 AM

It's just a number to represent all combinations of aperture and shutter speed that yield the same exposure. For example, EV0 equates to f1 at 1 second of exposure. It also equates to f2 at 1/2 second exposure, f4 at 1/4 second, f8 at 1/8 second, etc.

I have never found much use for it, but it is a nice convenient way for lightmeters (this all started in the days of analog meters) to only have to output one number instead of two.


That´s what I have been reading. I can´t find much use to.

Thank you
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#4 Adrian Sierkowski

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Posted 09 July 2009 - 08:33 AM

It's also a fun way to mess with the new guy on set, require all readings in EV. 100% guaranteed to irk 'em a little bit.
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#5 Ale Reynoso

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Posted 15 July 2009 - 10:00 PM

If you´re using a spotmeter with EV scale it´s a good way to work with the zonal system, knowing that the difference between EV´s is right one stop.
Instead of guessing the difference in F stops, you get a straight difference in natural numbers.
I.E. camera stop f 4.0. Dark side f 1.4.
In EV´s would be (i.e.) Zone V in camera EV 10. Dark side EV 7 (Zone III). I think it´s a straight and easier math.
Although I´m using a Minolta Spotmeter F that takes the things a little more easier:
I you get the Camera F stop, you set it in the meter as A (Average), then every reading is in EV, BUT STARTING AT THE AVERAGE MEASURE.
i.e. You read a gray card (i.e. f 2.8), then you set it as your average. Readouts over f 2.8 will be positive (1 stop over, or f 4.0 will read 1, 2 over or f 5.6: 2. And so on, with decimals intermediates). f 2.8 will be "0" (zero). Readouts under f 2.8 will give you negatives number (f 2.0 is -1, and so with the decimal intermediates).
I find it quite practical and easy to work with.
Best regards
Alejandro
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#6 Ram Shani

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Posted 15 July 2009 - 11:21 PM

i use it the same way all the time

to measure the contrast of a scene

i set the f/stop i want to the scene then i "tell" the meter it's EV0

then i every place i point the meter i can get an easy read of the stop difference

every Ev number represent 1 f/stop so if i see a EV3 it's 3 stop over and if it's -2.5EV it's 2.5 stop under

very easy and fast
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#7 Bruno Alzaga

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Posted 23 July 2009 - 01:26 PM

i use it the same way all the time

to measure the contrast of a scene

i set the f/stop i want to the scene then i "tell" the meter it's EV0

then i every place i point the meter i can get an easy read of the stop difference

every Ev number represent 1 f/stop so if i see a EV3 it's 3 stop over and if it's -2.5EV it's 2.5 stop under

very easy and fast

This has benn very very useful.

Thank you very much!!! Muchisimas gracias!!!!
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#8 Ale Reynoso

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Posted 23 July 2009 - 06:41 PM

This has benn very very useful.

Thank you very much!!! Muchisimas gracias!!!!


Nice to have been usefull (not only my credit...). De nada!!
Saludos desde Buenos Aires!
Ale
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