After a year, the one thing that still boggled my mind was DOF and focus. I understood that the aperture controlled how much light came in, but so does the shutter speed. So if the subject isnt moving, does it matter what the aperture is? So I researched further and found that aperture also controls the "Depth of Focus". Lots of sites talk about this, but they hardly explained how this works with the Focus lens.
Then I found the Photospot Blog. It goes over DOF like all the other sites, but it goes more into how it relates with the Focus lens. From all this I gathered something I hope other people trying to master these controls.
The Focus lens sharpens your subject while the aperture determines how sharpened the background is.
A great site to learn how all these controls work together is the Shutter Bee.
While none of this is really important when taking photos. I took many great photos with my disposable cameras without knowing anything other than when to use flash. Automatic mode works rgeat 80% of the time, but the photos I want are in the other 20% =D. So I learn when to turn off automatic and how to use manual. For instance...
Automatic turns waterfalls into mud, manually setting the shutter speed makes them waterfalls.
Automatic focus takes forever when photographing people on the red carpet. Setting focus to a prepared spot, and snapping photos as the person crosses that point is better.
Taking macro shots in a ministudio are nice with automatic, but great with the aperture manually controlled.
Basically what I'm trying to say in this long post is that dont fret the not knowing manual, but as you learn how to master manual you'll think back to past photos (as I did) and say "thats the touch I needed". Also, on Photosig, any bad picture is great if you have a nude girl in it, not that theres anything wrong with nude girls.
Oh and Monday, I'll be upgrading from my Cannon Rebel to a Nikon D50 DSLR. Yup, gomi is going digital =D.
Reason 1. Photolabs wont "correct" my photos.
Reason 2. I can experiment and study the results quicker.
Reason 3. I can post the awesome pics on-line faster.
Reason 4. Nude girls are squimish that photolab techs will make copies ;)