Shutter + Aperture set up.

When you scroll through your wheels, what is your increment for Shutter + Aperture.

I have it set to 1/3 stops for both...But sometimes I forget what is actually a full (native/standard?) stop.

Probably the most commonly accepted convention for the "normal" series would be:
f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32, f/45, f/64, etc.
1s, 1/2s, 1/4s, 1/8s, 1/15s, 1/30s, 1/60s, 1/125s, 1/250s, 1/500s, 1/1000s, 1/2000s, etc.

Edit - sorry - I may have misunderstood your question.

C.Michael wrote in post #11766831
When you scroll through your wheels, what is your increment for Shutter + Aperture.

I have it set to 1/3 stops for both...But sometimes I forget what is actually a full (native/standard?) stop.

One click of the wheel will then be 1/3 a stop. I just count clicks.

What "other" is there?

Anders Östberg wrote in post #11767776
What "other" is there?

If people are using Nikon, or have a different method...

Such as.

Possibly 1/3 stops for shutter and full stops for apeture?

xarqi wrote in post #11766850
Probably the most commonly accepted convention for the "normal" series would be:
f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32, f/45, f/64, etc.
1s, 1/2s, 1/4s, 1/8s, 1/15s, 1/30s, 1/60s, 1/125s, 1/250s, 1/500s, 1/1000s, 1/2000s, etc.

Edit - sorry - I may have misunderstood your question.

Nope, that is what I was getting at!

I see that the Shutter values are exponential, is there some sort of formula for the aperture?

stickshift wrote in post #11766879
One click of the wheel will then be 1/3 a stop. I just count clicks.

True, cheers!

C.Michael wrote in post #11767882
, is there some sort of formula for the aperture?

Yes,there's a formula, but knowing it isn't really important - what matters is knowing that a FULL F-stop lets in twice or half the light of the next f-stop (depending on whether you are opening or closing the aperture.


Some common f-stops are not full (like f 1.8, 3.5, etc).

If you want to know the actual formula, it's simple enough - it's a relationship between the focal length of the lens as compared to the diameter of the aperture - divide the focal length by the diameter of the aperture and that gives you the f-stop -

For example, if the focal length is 100mm, and the aperture is open to 40mm, then the f-stop would be f-2.5 - which is not a "full stop" since full stops begin at f-1 and f-2.5 would not be a number that would allow in half (or in theory, twice) the light of any FULL aperture starting with f-1 - if the focal length is 100mm and the aperture is open to 25mm, then the f-stop would be f-4 - (a full stop) and so on.

The numbers are not linear like ISO - (ISO of 400 is twice as sensitive as ISO 200 and half as sensitive as ISO 800) - they are derived with a more complex formula to determine half and double the light.

My examples of f-3.5 and f 2.5 and f 1.8 are stops that exist as 1/3 stops - Which seems to be the most common way lenses are marked - although I've never seen a lens with ALL the 1/3 f-stops marked on the lens barrel. F 1.8 and f 3.5 are very common, I don't know if I've ever seen f 2.5 (maybe because it just looks so close to f 2.8 which is a full stop and lens barrels have a limited amount of room)??? I suppose it would be easy to have the LED display in the modern viewfinders calculate exact apertures, but it's not really important - what's important is knowing if the exposure is correct.

Peace,
D.

C.Michael wrote in post #11767882
Nope, that is what I was getting at!

I see that the Shutter values are exponential, is there some sort of formula for the aperture?

True, cheers!

Not exponential, geometric - there is a factor of 2 (with a bit of creative rounding applied in places) between each shutter speed value.

In the case of the f ratio (casually termed "aperture"), the factor is the square root of 2 or ~1.414. It's like this because when you double the diameter of the aperture (in the true sense), the amount of light transmitted goes up 4-fold, since the cross-sectional area has gone up 4-fold. To increase the transmitted light 2-fold, the diameter must go up by a factor of root 2.

Delija wrote in post #11768126
Yes,there's a formula, but knowing it isn't really important - what matters is knowing that a FULL F-stop lets in twice or half the light of the next f-stop (depending on whether you are opening or closing the aperture.


Some common f-stops are not full (like f 1.8, 3.5, etc).

If you want to know the actual formula, it's simple enough - it's a relationship between the focal length of the lens as compared to the diameter of the aperture - divide the focal length by the diameter of the aperture and that gives you the f-stop -

For example, if the focal length is 100mm, and the aperture is open to 40mm, then the f-stop would be f-2.5 - which is not a "full stop" since full stops begin at f-1 and f-2.5 would not be a number that would allow in half (or in theory, twice) the light of any FULL aperture starting with f-1 - if the focal length is 100mm and the aperture is open to 25mm, then the f-stop would be f-4 - (a full stop) and so on.

The numbers are not linear like ISO - (ISO of 400 is twice as sensitive as ISO 200 and half as sensitive as ISO 800) - they are derived with a more complex formula to determine half and double the light.

My examples of f-3.5 and f 2.5 and f 1.8 are stops that exist as 1/3 stops - Which seems to be the most common way lenses are marked - although I've never seen a lens with ALL the 1/3 f-stops marked on the lens barrel. F 1.8 and f 3.5 are very common, I don't know if I've ever seen f 2.5 (maybe because it just looks so close to f 2.8 which is a full stop and lens barrels have a limited amount of room)??? I suppose it would be easy to have the LED display in the modern viewfinders calculate exact apertures, but it's not really important - what's important is knowing if the exposure is correct.

Peace,
D.

Thanks for taking the time to explain that!
Very enlightening - Although I still feel a little confused about the focal length v aperture.

xarqi wrote in post #11768151
Not exponential, geometric - there is a factor of 2 between each shutter speed value.

In the case of the f ratio (casually termed "aperture"), the factor is the square root of 2, ~1.414, with a bit of creative rounding applied. It's like this because when you double the diameter of the aperture (in the true sense), the amount of light transmitted goes up 4-fold, since the cross-sectional area has gone up 4-fold. To increase the transmitted light 2-fold, the diameter must go up by a factor of root 2.

Hmmm, shows how rusty I am on maths.

I do get the point on doubling the diameter creates a area 4-fold though.

Thanks guys, this is really interesting - not what I was aiming for with my question, but loving it all the same.

Some smart fellows getting around here!

C.Michael wrote in post #11768375
Thanks for taking the time to explain that!
Very enlightening - Although I still feel a little confused about the focal length v aperture.

i think it's better explained the other way around: focal length / f-stop = pysical opening of the lens

example: a 400mm f/4 will have a 100mm opening. stopped down to f/8 it'll be 50mm.

f-stops are multiplied by 1.4 to get to the next "full" stop, which is roughly (rounded) the square root of 2. edit: has been said, but here again...

1 x 1.4 = 1.4
1.4 x 1.4 = 2
2 x 1.4 = 2.8
2.8 x 1.4 = 4
...

^^^ Nice simple rule of thumb - like it!

Like the OP I've just stayed with the default 1/3 increments for shutter/aperture and EC etc.

FWIW I've done the same for ISO but I tend to avoid the "in-betweeners" that come just after a "true" stop (supposedly more noise prone).

xarqi wrote in post #11768151
Not exponential, geometric - there is a factor of 2 (with a bit of creative rounding applied in places) between each shutter speed value.

actually...it's a factor of 2 between each stop of a shutter speed...not between each speed value (w/ the camera set in 1/3 stops). It'll be three clicks before the shutter speed is doubled from the original speed.
ie..if the shutter speed is at 1/50, to slow it down 1 full stop (halving the speed), it'd be 3 clicks to get to 1/25.

& further explanation on the creative rounding...it's applied to shutter speeds that aren't doubled/halved evenly. Take 1/25...1 stop down would technically be 1/12.5 sec, but the cam's can't do that. So 1/12.5 is rounded to 1/10th.

C.Michael wrote in post #11768375
Thanks for taking the time to explain that!
Very enlightening - Although I still feel a little confused about the focal length v aperture.

Sorry - maybe it would have been more clear is I had added three words to "focal length" in my example of 100mm focal length - that should have been "focal length OF THE LENS"...

So a 100mm LENS with an aperture that opens to 50mm wide (diameter) would be f-2 (a full stop)...... And as I already used as an example, if the aperture of the same 100mm lens is opened to a diameter of 40mm, then the f stop would be f -2.5 (not a FULL stop based on an aperture starting at f 1)...the 25mm aperture on the 100mm focal length LENS would be f-4 (a full stop).

The formula using the base (f-1 - or equal aperture diameter and focal length of the lens)...divided by the square roots of 2 to get to each consecutive full stop is accurate, but not necessary to know. (The approach of multiplying by 1.4 seems easier, but no more necessary to know in the field).

It's just seems easier to me - and helpful to remember the full stops as were listed in the first response in this thread....very useful if shooting and relying on the "Rule of Sunny 16".... people still use (or at least did until digital came along) old German rangefinder cameras without meters and rely on feel and techniques that may seem archaic -But there's something to be said for traveling light and having a feel developed over many years - today, with tiny and very good shirt pocket sized digital cameras, maybe it's not as necessary to depend on experience, but there's no such thing as useless knowledge.

Peace,
D.

1/3 stop... but now that you mention it, I might set to half stops.

josullivan79 wrote in post #11768878
actually...it's a factor of 2 between each stop of a shutter speed...not between each speed value (w/ the camera set in 1/3 stops).

Quite so. Given the context of the listed series though, I think the meaning was pretty clear.

Thanks.