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Hi
Another newbie question,probably a dumb one too But here it is:
When people talk about aperture size or F stops, when they say a LARGER Aperture do they mean a large hole and a small f stop number or they mean a small hole but large aperture number?

Not a dumb one, and one that confuses myself at times - so I usually revert to saying at the time I mean the move in f-stops, or making the hole bigger or smaller! I have never really sat down and checked which way is correct!
No doubt one of our learned friends will answer shortly

hi

larger aperture means the lowest number e.g f2.8
translates to elemetns close to you are sharp and background is blured an effect known as 'bokeh', low fstop is good for throwing the background out of focus so your subject(near you) is clear, master this and your well on your way to being a good photographer

Smaller aperture means the highest number f22 which translates to more depth of field, everything in focus, used for landscapes.
Elements close to you, medium distance and far away are in sharp focus,
of course everything is relative so if your too close to something that will obviously be blurred according to the minimal focus distance of your lens.

Sweetspot for smaller aperture on most lenses range from f4 to f11 f8 being the best. You need to experiment or you can get scientific and obtain a Depth of Field Chart. When you get more advanced you will learn about 'Hyperfocal' measurements for Depth of Field

Cool. . that is pretty clear, we are talking about the hole size not the numeric f stop measure..

Now i need to embed that terms in ..

Think of the f stop as a fraction so F/2 would be 1/2 or 50% of the light coming through your lens and say F16 would be a 1/16th of the light coming through your lens.
So f/2 would be a large apperture and f/16 would be small.
Another way of thinking about is like a water pipe with the pipe diameter your apperture and the shutter speed your water flow.
Confusing, yes! I took me a while to get my head around it as well.

Edit, wendel beat me to it! well explained Wendel!

A larger aperture mean a small /f.. eg 2.8... It refers to the size of the opening. The smaller the aperture number the larger the opening.

Edit: I new i typed to slow.. got beaten to it.

gMaster wrote:Cool. . that is pretty clear, we are talking about the hole size not the numeric f stop measure..

Now i need to embed that terms in ..

they are related as well as everyhting to do with aperture, shutter speed and ISO, make one change here and it will affect the other two.

larger apertures(lowest fstop number) is good for low light conditions say indoor portraits with available light. More light is allowed through the lens so your shuter speed can be faster

say your using a 50mm lens shutter should be the reciprocal of that value say a 50th of a second or faster to avoid blurry images

now in most cases that will produce a dark picture, to counter you make your aperture bigger 2.8 / 1.4 or increase ISO, your subject will be clear and the background blurred

now if your taking a picture of a ceiling which is mid distance to you
a large aperture 2.8 will make the image a bit blury because there is more distance, so you need to start calculating depth of field.

wendellt wrote:

gMaster wrote:Cool. . that is pretty clear, we are talking about the hole size not the numeric f stop measure..

Now i need to embed that terms in ..

they are related as well as everyhting to do with aperture, shutter speed and ISO, make one change here and it will affect the other two.

larger apertures(lowest fstop number) is good for low light conditions say indoor portraits with available light. More light is allowed through the lens so your shuter speed can be faster

say your using a 50mm lens shutter should be the reciprocal of that value say a 50th of a second or faster to avoid blurry images

now in most cases that will produce a dark picture, to counter you make your aperture bigger 2.8 / 1.4 or increase ISO, your subject will be clear and the background blurred

now if your taking a picture of a ceiling which is mid distance to you
a large aperture 2.8 will make the image a bit blury because there is more distance, so you need to start calculating depth of field.

A few good tips there ... so much to learn .... and so little time/money ...

Here's the best tip on this - our very own exposure tutorial. There's also a link on our home page. Download and print it off; it's very well written, and, like all of our tutorials, contains valuable information.

Paul wrote:Think of the f stop as a fraction so F/2 would be 1/2 or 50% of the light coming through your lens and say F16 would be a 1/16th of the light coming through your lens.

Slight technicality Paul, but at f/16 you have 1/64 th of the light you have at f/2. The f-stops refer to the diameter of the aperture in relation to the focal length (f); each stop means 1/2 the light; these numbers go up by sqrt(2), or about 1.41. So in full stops from f/2, we have f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, i.e. 6 stops, so you'll get (1/2)^6 = 1/64 th the amount of light at f/16 that you had at f/2.