fjrabon
Been spending a lot of time on here!
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I told somebody about this a few days ago and they found it pretty helpful.
Most beginners, heck most intermediates, have trouble calculating equivalent exposures in their head. It's a useful thing to be able to do, but they just get lost in the math. For most people shutter speed and ISO are easy enough. They're intuitive numbers. 1/100 of a second is obviously twice as fast as 1/50 and this lets in half as much light. That is, it's a stop difference. Same thing with ISO. Obviously 200 is half 400, so 400 is twice as bright and thus a stop different.
But for many photographers, things go sideways when it comes to aperture. They don't have a clear, intuitive sense of the relationship between f/8 and f/5.6.
Most experienced photographers manage this by simply having memorized f/stops through years of experience (especially when they were set tactilely on the lens and you were forced to look at the actual number each time). They know 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22 like the back of their hand. Is the only solution to just memorize these?
You only need to memorize two f/stops and then you can use a simple trick to get all the rest.
Start with f/1.4 and f/2. Have those memorized. They're 1 stop apart, meaning f/1.4 lets in twice as much light.
Then you just alternate doubling each. So the next stop after f/2 is f/2.8 which is double f/1.4. Next is f/4 (double f/2).
See the alternating pattern: 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45
Now you'll note the pattern gets broken twice. But it actually doesn't. f/11 should really be f/11.2, but the .2 is such a tiny difference in light that we round it off because it's easier to write on lenses. f/22 should be f/22.4, again it's just rounded down. Then f/45 should be f/44.8.
It also works for third stops too, but you have to memorize 4 additional starting points then.
Honestly I could do without third stops for the most part. I tend to think of them more as "strong" and "weak" standard stops. Historically they were really more because a lens was either messed up or was a prime on the bleeding edge of its capabilities.
Anyway, I generally find that f/stops are the last thing keeping people from being able to find equivalent exposures in their head, which can come in incredibly handy at times when you can't simply use the camera's built in light meter.
Star photography for example. Changing from a f/2.8 wide angle to a f/2 prime? Gotta be able to do the equivalent exposure in your head because light meters are useless with star photography.
Anyway, hope somebody find that little trick helpful.
Most beginners, heck most intermediates, have trouble calculating equivalent exposures in their head. It's a useful thing to be able to do, but they just get lost in the math. For most people shutter speed and ISO are easy enough. They're intuitive numbers. 1/100 of a second is obviously twice as fast as 1/50 and this lets in half as much light. That is, it's a stop difference. Same thing with ISO. Obviously 200 is half 400, so 400 is twice as bright and thus a stop different.
But for many photographers, things go sideways when it comes to aperture. They don't have a clear, intuitive sense of the relationship between f/8 and f/5.6.
Most experienced photographers manage this by simply having memorized f/stops through years of experience (especially when they were set tactilely on the lens and you were forced to look at the actual number each time). They know 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22 like the back of their hand. Is the only solution to just memorize these?
You only need to memorize two f/stops and then you can use a simple trick to get all the rest.
Start with f/1.4 and f/2. Have those memorized. They're 1 stop apart, meaning f/1.4 lets in twice as much light.
Then you just alternate doubling each. So the next stop after f/2 is f/2.8 which is double f/1.4. Next is f/4 (double f/2).
See the alternating pattern: 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45
Now you'll note the pattern gets broken twice. But it actually doesn't. f/11 should really be f/11.2, but the .2 is such a tiny difference in light that we round it off because it's easier to write on lenses. f/22 should be f/22.4, again it's just rounded down. Then f/45 should be f/44.8.
It also works for third stops too, but you have to memorize 4 additional starting points then.
Honestly I could do without third stops for the most part. I tend to think of them more as "strong" and "weak" standard stops. Historically they were really more because a lens was either messed up or was a prime on the bleeding edge of its capabilities.
Anyway, I generally find that f/stops are the last thing keeping people from being able to find equivalent exposures in their head, which can come in incredibly handy at times when you can't simply use the camera's built in light meter.
Star photography for example. Changing from a f/2.8 wide angle to a f/2 prime? Gotta be able to do the equivalent exposure in your head because light meters are useless with star photography.
Anyway, hope somebody find that little trick helpful.
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Rather than looking at mathematical relationships between the f-stops and seeing that pattern, they could also link those f-stop numbers to images and establish a different kind of pattern.
