Yesterday my first csc camera arrived. The first camera that has lenses I can change. I am used to my compact. I am confused though, my kit lens is 14-42mm and has a f3.5-5.6. Whilst having first play with it the aperture settings I can get whilst setting the aperture manually is from 3.5 through to 22. I'm confused...what are the aperture settings with my kit lens on? How does that work in terms of depth of field? My compact has an aperture range from 2-8 I am used to controlling the aperture on it in aperture priority mode and achieving dof with it. Sorry hope this makes sense as a question. Basically can anyone explain to me what aperture numbers given on lenses mean?
When the lens has f3.5-5.6 it is saying that the widest aperture at 14mm is f3.5 and the widest aperture at 42mm is f5.6. They never put the smallest aperture on the lens. At any focal length you can smaller apertures.
@newbank It's the same with your CSC lens 14-42mm lens: the wider the aperture in use, the less the depth of field. You already uses aperture priority because you want to control DOF… carry on in the same way, it will cover most of your needs. As John says, the lens won't tell you the range of apertures available. If you haven't already tried this, switch the camera on, set to aperture priority, and point it at your chosen subject. When you rotate the wheel you will see the apertures on the screen. You can also choose exposure compensation by pressing in the wheel briefly and then rotating it to show + or - 1/3 2/3, 1 etc depending upon how you have chosen to set this in the menu. Happy Playing!
@newbank PS the aperture numbers indicate the ratio of the aperture to the focal length - the old fashioned way of writing it is the one I still use: f/2 means that your aperture is half the focal length, f/16 one sixteenth the focal length etc. These days they usually just label them as 2, 16 etc.
@newbank When I started, I tried to remember:
Small number = large aperture (or in English, very wide opening in the lens).
Small number being something like 5.6, 4.0 etc
Lets in lots of light but has shallow DOF (or band of sharpness)
Large number = small aperture and opposite of above.
Large number being 11, 13, 22, 32 etc
The smallest an largest numbers you get on a lens will depend on the focal length of the lens, they make and how well it's made.
Probably already been said above but that's how I used to remember it.
Aperture Priority is my favourite mode for shooting
@yrhenwr Actually ratio of focal length to aperture diameter, but the next sentence is correct if by "aperture" you mean diameter of the aperture. That's why, by the way, that f/stop is not a linear thing. Twice the f/stop is not 1/2 the exposure, but 1/4 since the light entering is proportional to the area, and that is proportional to the *square* of the diameter.
Since a limit of the aperture is the diameter of the lens barrel, it explains why "wide open" at 42mm focal length might be a smaller ratio (larger f/stop) than wide open at 14mm.
But don't sweat it too much for background blur. Just remember that if the distance from the subject back to background is 3 or more times the distance from the subject to the camera, you'll almost assuredly get pretty decent blur at any f/stop. These distance proportions are way more important to "blurring the background" than an f/stop number. Risking people turning off again over jargon this is the "hyperfocal distance" effect, that you can read about by searching any reference on line. It can serve also to explain why with real close up shooting (macro focus) you really can't help but blur the background at almost any f/stop.
@motherjane@lynnilou Don't get overwhelmed. It's only simple arithmetic, with the *diameter* on the bottom of the fraction. :)
@frankhymus Yes, of course aperture means diameter. As for the rest it sure turned me of! Mention of 'hyper focal distance' always does that to me! It sure sounds important, but it is so difficult to judge in field situations that the only sensible response is to forget it.
@newbank Wow you have a lot of info here!! In answer to your original question (which I realise you may have answered by now), I will try to give you a simple explanation!!
Like John said, when you are buying/looking at lenses, they are named after their MAXIMUM aperture. So a lens will be listed as (for example) f/1.4, f/2.8 or f/3.5-5.6. Usually only prime lenses (that don't zoom) will be f/1.4 or similar. But each of these lenses will also close down through all the f stops to f/22 or further.
Many zoom lenses (like your 14-42) are f/3.5-5.6, which means the biggest aperture you can get zoomed all the way out is 3.5, and when you are zoomed all the way in, the biggest you can get is f/5.6 (and f/4, 4.5, 5 at your in-between zoom lengths). But at ANY focal (zoom) length you can also close down from f/6.3 all the way down to f/22.
Some more expensive zoom lenses are "constant f/2.8" which means that you can zoom all the way in or out and still get a maximum aperture of 2.8. And close down at any length to f11, 16, 22 etc.
I hope I've managed to tell you something useful :)
@newbank Aw...that's so cool that you think of me as expert enough to answer! I appreciate the vote of confidence! Sorry I was late in reading this -- the information in this thread seems pretty comprehensive now.
Little I can belatedly add here, sorry, was in London all day yesterday and didn't check in to 365. It sounds like you've cracked it now. I promise you it will become intuitive the more you use it, though you may go backwards before you go forwards!
@frankhymus What you say is right, Frank, but in certain situations - macro shots for example, there is often not a lot of distance between subject and background. At the opposite extreme, in big landscape situations, it is difficult to judge the hyper focal distance: how do you locate one-third the way into a scene when the far distance is - from a 'lens eye' view - 'infinity'? Many lenses these days don't come with a distance scale attached. Maybe these are not the scenarios you had in mind. It's fun to argue the finer points but this thread began with a plea for help concerning aperture settings and depth of field so maybe we should stick to the general principles that might be of some help to the questioner.
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Small number = large aperture (or in English, very wide opening in the lens).
Small number being something like 5.6, 4.0 etc
Lets in lots of light but has shallow DOF (or band of sharpness)
Large number = small aperture and opposite of above.
Large number being 11, 13, 22, 32 etc
The smallest an largest numbers you get on a lens will depend on the focal length of the lens, they make and how well it's made.
Probably already been said above but that's how I used to remember it.
Aperture Priority is my favourite mode for shooting
Since a limit of the aperture is the diameter of the lens barrel, it explains why "wide open" at 42mm focal length might be a smaller ratio (larger f/stop) than wide open at 14mm.
But don't sweat it too much for background blur. Just remember that if the distance from the subject back to background is 3 or more times the distance from the subject to the camera, you'll almost assuredly get pretty decent blur at any f/stop. These distance proportions are way more important to "blurring the background" than an f/stop number. Risking people turning off again over jargon this is the "hyperfocal distance" effect, that you can read about by searching any reference on line. It can serve also to explain why with real close up shooting (macro focus) you really can't help but blur the background at almost any f/stop.
@motherjane @lynnilou Don't get overwhelmed. It's only simple arithmetic, with the *diameter* on the bottom of the fraction. :)
Like John said, when you are buying/looking at lenses, they are named after their MAXIMUM aperture. So a lens will be listed as (for example) f/1.4, f/2.8 or f/3.5-5.6. Usually only prime lenses (that don't zoom) will be f/1.4 or similar. But each of these lenses will also close down through all the f stops to f/22 or further.
Many zoom lenses (like your 14-42) are f/3.5-5.6, which means the biggest aperture you can get zoomed all the way out is 3.5, and when you are zoomed all the way in, the biggest you can get is f/5.6 (and f/4, 4.5, 5 at your in-between zoom lengths). But at ANY focal (zoom) length you can also close down from f/6.3 all the way down to f/22.
Some more expensive zoom lenses are "constant f/2.8" which means that you can zoom all the way in or out and still get a maximum aperture of 2.8. And close down at any length to f11, 16, 22 etc.
I hope I've managed to tell you something useful :)