aperture f/stops???

[kandyredcoi]

can someone please list the "FULL" stops in the aperture range?

when scrolling thru my cameras Av stops there seems to be a lot of stops available, but im not quite sure which numbers are described as a full complete f/stop number?

any info would be great

thank you

[SkipD]

The classic full f-stop values are: 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, etc.

Notice the difference between one f-stop value and the next is a multiple of 1.414 (the square root of 2), with a little bit of rounding here and there.

In addition - here are the age-old standard shutter speeds (1 second and faster) which are a full "stop" apart. 1 second, 1/2, 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, 1/2000, etc.

Notice the rounding. The difference between 1/120 (1/2 the speed of 1/60 second) and the classic step of 1/125 second, for example, is insignificant in the real world.

[Todd Lambert]

Do you have your camera set up to show 1/3 stops or 1/2 stops?

[kandyredcoi]

^in ISO or exposure?

i didnt see a mode where u can change the f/stop increments, unless i missed it somewhere?

thanx skipD

[Todd Lambert]

Ah, didn't read this closely enough... thought you were referring to ISO..

You should see whatever the highest ƒ that the lens is capable of, up to lowest available... for instance: 2.8, 4, 5.6, 8, 11, 16, 22

[kandyredcoi]

gotcha!

[SOK]

Have a read of this: http://www.uscoles.com/fstop.htm

It give some good background about where the numbers come from.

[20droger]

^in ISO or exposure?

i didnt see a mode where u can change the f/stop increments, unless i missed it somewhere?

thanx skipD
It's C.Fn I-1, right there on page 174 of your EOS 5D Mark II manual.

C,Fn I-2 changes the ISO increments.

[kandyredcoi]

^thanx, i was not speakin of the ISO but the aperture f/stops

[Todd Lambert]

What exactly are you seeing in fstops?

[kandyredcoi]

from 1.4 it goes to1.6-1.8-2.0-2.2-2.5-2.8-3.2-3.5-4.0-4.5-5.0-5.6 and so on

im not sure which of those numbers are a complete whole "f/stop" value?

[Todd Lambert]

Hmmm... well, as Skip posted, the classic full stops are:

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

But, there are obviously others - such as 1.8 aka the thrifty fifty.

[kandyredcoi]

^yea thats why im getting confused over here :p

ill stick with the classic style for now

also for instance...i did a concert with a buddies 70-200 2.8 non-is but i put a 2x extender on it
if i shot in Av and left the aperture at 2.8 i know that the 2x looses 2full stops so what f/stop is the lens operating at with the extender mounted on it?

thanx Todd

[ryant35]

^yea thats why im getting confused over here :p

ill stick with the classic style for now

also for instance...i did a concert with a buddies 70-200 2.8 non-is but i put a 2x extender on it
if i shot in Av and left the aperture at 2.8 i know that the 2x looses 2full stops so what f/stop is the lens operating at with the extender mounted on it?

thanx Todd

The max aperture would be f/5.6 with the 2X on. You cannot select f/2.8 with the extender on. I only use extenders for shoots during the day with a decent amount of light.

[kandyredcoi]

^i hear ya, heres a few samples from the concert with the 70-200/2.8 with 2x
http://img.photobucket.com/albums/v476/fluxmr2spyder/concerts%20and%20events/IMG_9681.jpg
http://img.photobucket.com/albums/v476/fluxmr2spyder/concerts%20and%20events/IMG_9784.jpg

[ryant35]

The second one looks good, nice and sharp. I guess the low light comment doesn't apply when you have a 5D2 that can handle the high iso.

Is that woman in the background of the first image blowing her nose on stage?:rolleyes:

[kandyredcoi]

yes doing a concert while she was under the weather :( FTL

[Todd Lambert]

Nice shots... esp indoors with a 2x. As Ryan said, that's usually a no-no... but the 5D2's awesomeness again, makes the impossible possible (well not really, but since I'm being elaborate I might as well roll with it... hehe)

[SkipD]

from 1.4 it goes to1.6-1.8-2.0-2.2-2.5-2.8-3.2-3.5-4.0-4.5-5.0-5.6 and so on

im not sure which of those numbers are a complete whole "f/stop" value?As you can see by my highlighting the traditional full-stop values, you have the camera set to 1/3 stop increments. My 20D can use 1/2-stop or 1/3-stop increments.

You can set modern handheld meters to 1/2 or 1/3 stop increments. It's usually a good idea to have your handheld meter (assuming you have one) and the camera set to use the same increments.

[20droger]

It's C.Fn I-1, right there on page 174 of your EOS 5D Mark II manual.

C,Fn I-2 changes the ISO increments.

^thanx, i was not speakin of the ISO but the aperture f/stops
CnFn I-1 is how you change your aperture f/stops from 1/3 stops to 1/2 stops. Simultaneously, shutter speed will also change from 1/3 stops to 1/2 stops.

As Skip has pointed out twice, whole f/stops follow the traditional sequence. Your 5D II has an aperture range of f/1 to f/91. This means that the camera will set the exposure to any aperture within that range that is supported by the lens. The camera cannot set an aperture that the lens does not support.

For the 5D II, the entire whole-stop sequence is 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, and f/91. You should memorize these numbers.

When using 1/3-stop increments, the standard sequence becomes: f/1.0, f/1.1, f/1.2, f/1.4, f/1.6, f/1.8, f/2.0, f/2.2, f/2.5, f/2.8, f/3.2, f/3.5, f/4.0, f/4.5, f/5.0, f/5.6, f/6.3, f/7.1, f/8.0, f/9.0, f/10, f/11, f/13, f/14, f/16, f/18, f/20, f/22, f/25, f/29, f/32, f/36, f/40, f/45, f/51, f/57, f/64, f/72, f/81, f/91. Whole stops (red) are every third value.

When using 1/2-stop increments, the standard sequence becomes: f/1.0, f/1.2, f/1.4, f/1.7, f/2.0, f/2.4, f/2.8, f/3.4, f/4.0, f/4.8, f/5.6, f/6.7, f/8.0, f/9.5, f/11, f/13, f/16, f/19, f/22, f/27, f/32, f/38, f/45, f/54, f/64, f/76, f/91. Whole stops (red) are every other value.

[weezerfan84]

^yea thats why im getting confused over here :p

ill stick with the classic style for now

also for instance...i did a concert with a buddies 70-200 2.8 non-is but i put a 2x extender on it
if i shot in Av and left the aperture at 2.8 i know that the 2x looses 2full stops so what f/stop is the lens operating at with the extender mounted on it?

thanx Todd


5.6

One stop was 4. The second stop is 5.6

[kandyredcoi]

^thanx weezer!

[egordon99]

Just like remembering the multiplication tables (or the Fibonnaci sequence?), you just have to drill into your head -
1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16......

Basically, to get to the NEXT number, you multiply by SQRT(2), and obviously SQRT(2)*2=2, hence the doubling of every other number.

[DAMphyne]

In the early days, with all mechanical controls, the f-stop was a ring around the lens that was indented at the Half-stops. Although some were free turning, with no set number, just "match the needle" of the meter. Whole stops were displayed on the ring, but sometimes if the widest aperture were an unusual # the ring would display what we think of as ‘odd’ full stop numbers.

You set the ASA(ISO) with a wheel on the camera, setting the meter sensitivity.
Set the Shutter Speed with another wheel on the camera,
Turn the A-ring until the needle centers,
Focus, compose, shoot.
Perfect picture.


Point is, there are no “Full-stop” #’s, a full stop is just a relationship between the settings used to get correct exposure. The numbers are just reference points.

20droger has a full list of all the “named” apertures, good reference.bw!

[20droger]

Just like remembering the multiplication tables (or the Fibonnaci sequence?), you just have to drill into your head -
1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16......

Basically, to get to the NEXT number, you multiply by SQRT(2), and obviously SQRT(2)*2=2, hence the doubling of every other number.
Actually, SQRT(2)*2=2.8.... SQRT(2)*SQRT(2)=2.

[egordon99]

Actually, SQRT(2)*2=2.8.... SQRT(2)*SQRT(2)=2.

oops.....

My excuse is I only minored in Mathematics, not majored.... :(

[20droger]

In the early days, with all mechanical controls, the f-stop was a ring around the lens that was indented at the Half-stops. Although some were free turning, with no set number, just "match the needle" of the meter. Whole stops were displayed on the ring, but sometimes if the widest aperture were an unusual # the ring would display what we think of as ‘odd’ full stop numbers.

You set the ASA(ISO) with a wheel on the camera, setting the meter sensitivity.
Set the Shutter Speed with another wheel on the camera,
Turn the A-ring until the needle centers,
Focus, compose, shoot.
Perfect picture.


Point is, there are no “Full-stop” #’s, a full stop is just a relationship between the settings used to get correct exposure. The numbers are just reference points.

20droger has a full list of all the “named” apertures, good reference.bw!
Not true. There IS a full-stop sequence (given here several times already), based upon the definition of the relative aperture and beginning at f/1, where the aperture diameter is equal to the focal length of the lens. The sequence goes both up and down, though f/0.7 lenses are scarcer than hen's teeth.

One should remember that the f/number is an expression of the relative aperture of a lens. It is a fraction where the numerator is "f": the focal length of the lens. Due to the way lenses work, all lenses pass the same amount of light, regardless of their focal lengths, when they have the same relative aperture.

[DAMphyne]

Not true. There IS a full-stop sequence (given here several times already), based upon the definition of the relative aperture and beginning at f/1, where the aperture diameter is equal to the focal length of the lens. The sequence goes both up and down, though f/0.7 lenses are scarcer than hen's teeth.

One should remember that the f/number is an expression of the relative aperture of a lens. It is a fraction where the numerator is "f": the focal length of the lens. Due to the way lenses work, all lenses pass the same amount of light, regardless of their focal lengths, when they have the same relative aperture.

So, what would be 1 full stop from 0.7?
My point is, no matter where you start, a full stop is either twice or ½ the exposure value determined by the meter.
We only use these so called "Set numbers" as a reference, basically they are a convention for referring to exposure.
Have you used a free rotating aperture lens? with no F-stop in-dents?
You'll understand if you have.

[20droger]

So, what would be 1 full stop from 0.7?
My point is, no matter where you start, a full stop is either twice or ½ the exposure value determined by the meter.
We only use these so called "Set numbers" as a reference, basically they are a convention for referring to exposure.
Have you used a free rotating aperture lens? with no F-stop in-dents?
You'll understand if you have.
Yes, I have used a lens with free-rotating aperture. That does not alter the fact that, by definition, there are absolute whole-stop values.

You appear to be confusing relative stops with absolute stops. A change of one whole stop relative to a current stop setting is an increase or decrease of a factor of two. A change of one whole stop increase from f/0.7 would be f/0.5, and a change of one whole stop decrease from f/0.7 would be f/1.0.

Absolute whole stops are based upon f/1, by definition. and by long convention. I'll not give the defined sequence again.

The OP asked what the whole-stop f/numbers on his camera were, among all the displayed f/numbers. He did not ask what a whole stop change from a given f/number was. His question was correctly answered, several times.

By introducing relative stop changes, you are simply confusing the issue.

By stating that there is no such thing as whole-stop numbers, you are flying in the face of the defined nature of f/numbers and in the face of long-established convention.

This, of course, is your right. But let us not further confuse a newbie to the field with unorthodox approaches.

The concept behind aperture f/numbers, while simple, is not intuitive to everyone and therefore confusing enough as it is.

[DAMphyne]

I took a day to respond to your comments because I'm a little puzzled by your position.

I feel like you are scolding me for having the gall to point out that F-numbers(and shutter speeds, and now sensor sensitivity) are infinitely variable. This is an "Absolute".
You quoted my post that pointed out the convention of naming certain f-stops for the purpose of recording exposure. The only thing absolute about that set of numbers is their relationship to the diameter of the lens and the opening of the diaphragm.

I did read the OP's question, and referred to your wonderful list in one of your post( I even labeled it book worthy).

I think we will soon see the day when "Set" F-numbers, shutter speeds, ISO rating will be a thing of the past.