Am I going mad? (Aperture question!)

NorthstaNder

NorthstaNder

NorthstaNder

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I think I am you know... Being new to all this I have been reading an awful lot lately, and maybe my brain is becoming a bit scrambled! Anyway, onto my question...

I thought that a large, open aperture (small f/stop) meant more of the frame would be in focus and that a small, closed aperture (large f/stop) meant that just the subject would be in focus (ie...a flower for example).

I've just been re-reading my camera's manual (Fuji S6500fd) and it sugests the opposite...

"By adjusting the aperture, you can change the depth of focus. Selecting a larger number of aperture (closed) obtains a larger depth of focus. Selecting a smaller number of aperture (open) has the area in front of and behind the subject out of focus".

Am I bonkers?
 
Indeed a large aperature of say 2.8 (wide open) will give a very small DOF area of focus infront and behind the subject....this will give a very out of foucs blurred look to the background. A small aperature of 22 will create a very large DOF meaning that everything in the exposure should be in focus, mainly used in landscape photography.....

Hope that helps?

Smaller f/x numbers mean a larger opening and larger numbers mean a smaller opening = less light hitting the sensor
 
dont worry mate, i have just been in the same boat as you. i think it just clicks and then you understand how everything works together. i was exact the same as you until the other day when i was reading a photo mag and all i had been reading had seemed to sink in that very moment lol

try writing it down and taking notes, that helped me and maybe study pics u like the style of and check the settings that produced it then match it together mate.

bug these guys on here aswell, i know they are dying to help us noobies out :P
 
Thanks for your replies folks. It's reasuring to know I'm nuts :D

Seriously though, there is a hell of a lot to take in. I will take some notes as suggested and I'm sure it'll all fall into place soon.
 
Depth of focus/field does not mean what is in focus across the frame but rather what is in focus from front to back.

This diagram illustrates it;

dof_diagram_general.jpg


The smaller the f number (f1.8 etc) the smaller the depth of field and the shorter that arrow will be in that diagram and the bigger the f number (f32 etc) the bigger the DOF the longer the arrow.

This diagram shows how this works. Imagine the camera where the aperture is shown in this diagram pointing towards the subject and you can see just how different apertures affects DOF

cam3.gif


HTH
 
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