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09-20-2012, 05:26 PM   #1
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so exactly how much light is -3 EV?

I have been looking all over the net to have some comparison of how much light it would be (new K5II) and can't find anything. anyone have an idea?



09-20-2012, 05:38 PM   #2
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To properly expose a -3EV scene you would need something like ISO 800, f1.4 and a 2 second shutter.
09-20-2012, 05:47 PM   #3
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Exposure value - Wikipedia, the free encyclopedia
Full moon, so they say.
Something like these shots:

09-20-2012, 07:07 PM   #4
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nice shots there

09-20-2012, 07:54 PM   #5
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EV depends on the ISO setting, though the convention is EV(100). -3 EV(100) is the amount of light that would indicate a 15s exposure at f/1.4 with the camera sensitivity set to ISO 100. To get a better idea of what this means, my K10D has a meter sensitivity of 0 EV(100) and that only barely. The meter simply will not respond to less light. The K-30 requires 1/15th as much light to retain meter functionality.

So, what does this mean in practical terms? How about accurate wide-open metering with relatively slow (say f/4) lenses in VERY low light. For those of us that use stop-down metering with legacy glass, it means accurate metering stop-down metering at moderate apertures in dim light.

09-20-2012, 08:34 PM   #6
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Here's a helpful chart to help visualize it: Exposure value - Wikipedia
09-20-2012, 08:57 PM   #7
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QuoteOriginally posted by elliott Quote
To properly expose a -3EV scene you would need something like ISO 800, f1.4 and a 2 second shutter.
Putting it into a night-time landscape shooting situation:

30s, f/1.8, ISO80 = -2.9 LV

Since you would not shoot a landscape with that open an aperture due to DOF & sharpness considerations, you'd be operating in Bulb-mode territory:

160s, f/4, ISO80 = -3 LV
320s, f/5.6, ISO80 = -3 LV
640s, f/8, ISO80 = -3 LV

That's dark.


Last edited by dosdan; 09-20-2012 at 09:30 PM.

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