Green Button Question

**eccs19** · 01-17-2009, 01:41 PM

I've recently noticed that on my Takumar lenses, that when I use the green button to meter, the slowest that I get it to meter is 1.5 seconds. I'm not sure if it's also the case with my auto lens. Just wondering if that's best I'll get out of my ist D, or am I doing something wrong. Maybe if it's to dark, it just can't meter any better than that?

blende8 · 01-17-2009, 02:33 PM

Originally posted by eccs19

Maybe if it's to dark, it just can't meter any better than that?

That's probably the reason.
The light meter can measure from about EV 0 - 19.
0 means 1s at aperture 1 and ISO 100.
You can do the maths.

rpriedhorsky · 01-17-2009, 03:38 PM

Originally posted by blende8

That's probably the reason.
The light meter can measure from about EV 0 - 19.
0 means 1s at aperture 1 and ISO 100.
You can do the maths.

That raises a question... how do you figure out the shutter speed to use for longer exposures? Shoot and check the histogram seems laborious if you're open for 10+ seconds plus the same again for noise reduction.

Reid

Mike Cash · 01-17-2009, 04:03 PM

Originally posted by rpriedhorsky

That raises a question... how do you figure out the shutter speed to use for longer exposures? Shoot and check the histogram seems laborious if you're open for 10+ seconds plus the same again for noise reduction.

Reid

Start with something under 10 seconds so you don't have to wait for noise reduction. Check your histogram and estimate if you're one, two, or more stops off and adjust accordingly. Eight seconds is only one stop away from fifteen seconds, and only takes eight seconds to get a trial exposure, compared to the thirty seconds it takes to get a trial shot on a fifteen second exposure.

01-17-2009, 01:41 PM	#1
eccs19 Site Supporter Join Date: Jul 2008 Location: Lisle, Ontario Photos: Gallery Posts: 1,510	Green Button Question I've recently noticed that on my Takumar lenses, that when I use the green button to meter, the slowest that I get it to meter is 1.5 seconds. I'm not sure if it's also the case with my auto lens. Just wondering if that's best I'll get out of my ist D, or am I doing something wrong. Maybe if it's to dark, it just can't meter any better than that?

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01-17-2009, 02:33 PM	#2
blende8 Veteran Member Join Date: Feb 2007 Location: Bremen, Germany Photos: Albums Posts: 1,521	Originally posted by eccs19 Maybe if it's to dark, it just can't meter any better than that? That's probably the reason. The light meter can measure from about EV 0 - 19. 0 means 1s at aperture 1 and ISO 100. You can do the maths.

01-17-2009, 03:38 PM	#3
rpriedhorsky Senior Member Join Date: Dec 2008 Location: Minneapolis Posts: 210	Originally posted by blende8 That's probably the reason. The light meter can measure from about EV 0 - 19. 0 means 1s at aperture 1 and ISO 100. You can do the maths. That raises a question... how do you figure out the shutter speed to use for longer exposures? Shoot and check the histogram seems laborious if you're open for 10+ seconds plus the same again for noise reduction. Reid

01-17-2009, 04:03 PM	#4
Mike Cash Veteran Member Join Date: Jan 2007 Location: Japan Photos: Gallery Posts: 6,950	Originally posted by rpriedhorsky That raises a question... how do you figure out the shutter speed to use for longer exposures? Shoot and check the histogram seems laborious if you're open for 10+ seconds plus the same again for noise reduction. Reid Start with something under 10 seconds so you don't have to wait for noise reduction. Check your histogram and estimate if you're one, two, or more stops off and adjust accordingly. Eight seconds is only one stop away from fifteen seconds, and only takes eight seconds to get a trial exposure, compared to the thirty seconds it takes to get a trial shot on a fifteen second exposure.