Here is a LONG overdue photography tutorial about aperture. Think of aperture as the pupil of your eye. The smaller the aperture (higher number) the less light you let in and the bigger your aperture (smaller number) the more light you let in. Check out the nifty diagram below. F.stop is referring to the aperture number.
Smaller number = shallow depth of field (blurry background) and more light
Bigger number = deep depth of field (detailed background) less light
Here is picture number one. (ignore the drool and dirt on his face) This was taken 1/100 shutter speed, F. stop 20, and ISO 2500 Look at the detail of the bushes. We have a deep depth of field. Showing a lot of detail.
This one has a shutter speed 1/80, F.Stop 8.0, and ISO 320 This is a pretty big jump from f.stop 20 but see how the depth of field is getting more shallow.
Here is a shutter speed 1/100, f.stop 4.0, and ISO 125. This is the widest the aperture will go for this lens. See how shallow the depth of field is? Here is a nice blurry background!
Notice how my ISO and shutter speed are affected when I adjusted the aperture. They all work together to get the exposure you desire. Now you go try it out! Link up your results on the before/after blog hop on Thursday! Got any questions feel free to email me or ask in the comment section.