I was wanting to go over Aperture again as it seems to be one of the many questions I get when people are learning. The concept that the higher the number (f/18) the smaller the opening boggles some people. I think that this is due primarily that most do not understand the mechanism in the lens itself.
Aperture in a lens works like the iris of an eye, when the eye is exposed to a great deal of light you can see the iris close making the pupil smaller to not overwhelm you with light. This is the same concept. The only difference is that we can control it, unless you are in a Auto Mode or another Creative Zone Mode that selects the aperture for you.
By definition of mathematics/geometry aperture is the inclination of lines that meet at a point. In Photography it is the hole inside the optic (glass) that telescopes the light, tubes it into the eye
The diaphragm that makes up the slats (stops) in a lens is the aperture. Take a look at the diagram on wikipidia. http://en.wikipedia.org/wiki/Aperture#In_photography
This diagram shows you the actual mechanics of an aperture.
I took my camera outside in the heat but knowing I had to wait for the sun to begin it's horizon's decent, so I grabbed my reflector, tripod and remote shutter to show you how Aperture effects your exposure. A sunny 16 rule in photography dictates that it is safer bet to use an aperture of f/16 so that you will not get over exposed shots. This is like all creative art is not set in stone. Its simply a guide. I did NOT use f/16 on my shots of the Pink Crepe Myrtles as I was loosing direct light but had available light to do these.
These are my new Crepe Myrtles in the yard. Enjoy and please comment or contact me. I would love to hear for you all.
ISO 100 f/13
ISO 100 f/13
ISO 100 f/7.1 (gold reflector)
ISO 100 f/10 (Gold reflector)
ISO 100 f/18 (Gold reflector)
ISO 100 f7.1 (Silver Reflector
