Exposure adjustments and filters

Rob Ruttan

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Joined

Nov 12, 2007

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76

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35mm

• Apr 5, 2008

• #1

Hey all, another of my rookie questions here! I've been experimenting with filters a bit. Obviously, I have to make an adjustment to my settings, and while simply taking a light reading through the filter seems o.k., I have a hunch it'll be less useful as I progress into GND filters, etc.. Plus, the more I understand, the more I understand. When I read up on this stuff, I sometimes find the instruction to adjust by, say, 2 1/2 (two and a half) f stops. What on earth is 'half' an f stop? I find the same instruction with extension tubes sometimes.

Thanks,

Rob

 

bdial

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Jan 2, 2005

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7,469

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North East U.S.

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• Apr 5, 2008

• #2

For this purpose, a half stop is 1/2 way in between any two f stop numbers on your lens. Some lenses have 1/2 stop detents to make that more reliable.

 

ann

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Joined

Sep 10, 2002

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3,336

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35mm

• Apr 5, 2008

• #3

it is exactly what it says. i.e. 5.6 to 8 there is a click between the two on your lens. that is half a stop

 

OP

OP

Rob Ruttan

Member

Joined

Nov 12, 2007

Messages

76

Format

35mm

• Apr 5, 2008

• #4

Thanks! I had wondered if it was that simple.

 

Christopher Walrath

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Dec 30, 2005

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7,175

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Milton, DE USA

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Analog

• Apr 5, 2008

• #5

Yeah, most of my lenses, between clicks, gradually adjust as I turn the aperture ring. SO if you really wanted a half stop adjustment you could just leave the aperture ring between settings to get a 1/2 stop adjustment.

 

hec

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Joined

Jul 16, 2004

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50

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Hermosillo,

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Multi Format

• Apr 5, 2008

• #6

Hello Rob, these are the apertures I get on my canon (1/2 stop steps):

4.0, 4.5, 5.6, 6.7, 8.0, 9.5, 11, 13, 16, 19, 22, 27, 32

Hope it helps.