[slideshow] Today I had a short opportunity to get outside and work with my gear. I wanted to practice a few techniques with my camera body, and check out how my new Pentax DA* 60-250 F4 will work. I used these four photos to demonstrate (to me because I because I may be the only one who reads this) the effect of aperture on the bokeh, or out of focus areas, in a photograph.
I shot this birdhouse at F14, F11, F5 and F4. The smaller the aperture the more depth of field you have in your photo. This means more will be in focus at F14 than F4. In this series you can see also how the larger aperture allows you to focus more on what you may want to be the focal point of the photo. In this case it is a simple photo with no artistic intent other than to demonstrate how being able to open up your lens aperture can be a powerful tool to a photographer.
So when you hear people lament that they "need" expensive fast glass...you can see what they should be using it for when the situation arises. You can isolate a model, a bird or bolt on a bridge if your tools will allow it in the space you have to work.