# A&P Aperture Math

Discussion in 'Lifestyle' started by hurleyint1386, Sep 22, 2008.

1. ### hurleyint1386Someone has sand in their vagina

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I've been looking at some f/stops and I've been thinking, there must be some kind of math behind it. I can't seem to find the pattern between 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45... etc I know it can go up to 256 (pinhole) but I was wondering where I can find out the math for this. Or are they just common f/stops with no pattern?

2. ### wizeguy4New Member

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http://www.uscoles.com/fstop.htm

3. ### hurleyint1386Someone has sand in their vagina

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Awesome, thanks a lot.

4. ### TedrzzNew Member

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they are roughly half of each other, and each time you go to the next smaller (in physical size) f-stop it will change your exposure 1 whole stop if you didn't adjust anything else.

5. ### hurleyint1386Someone has sand in their vagina

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That stuff I knew. I was just curious about the math between 1.4, 2.0, 2.8, 4, etc because 1.4 doubled isn't 2.0, and 2.0 doubled isn't even roughly 4.0 because 4.0 is 2 stops above 2.0. But with the ratios, it makes more sense to me.

Are you the guy that lives 3 blocks away from me?

6. ### TedrzzNew Member

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no i think that was the other dude, i live on elmwood

7. ### hurleyint1386Someone has sand in their vagina

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Still only a couple miles away! Rochester OTAP meet?

8. ### DR-GSROld Member

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fstop x sq root of 2 = next f stop

1x 1.4 =1.4
1.4 x 1.4 =2
2x 1.4 =2.8

etc

9. ### NetChemicaOT Supporter

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F stop * 1.4142135623730950488016887242097 = next f stop.

pretty easy to remember

10. ### QWIKSNKNew Member

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think about it in 2 stop increments..

1.4 -> 2.8, 2.8->5.6, 5.6 -> 11

2 -> 4, 4 -> 8, 8 -> 16

11. ### DavidNew Member

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So, using that math thingy, how does f/.95 work if you had a 50mm lens, wouldn't the diameter of aperture have to be like ~53mm?

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