One of the cool things about digital cameras is that there is no film, therefore no cost to taking pics (other than "shutter count").
When I started, a person once told me, for learning- "with digital (compared to the cost of film), the only bad pic, is one you
didn't take."
When I got my first camera- a canon point and shoot powershot, I spent hours just taking pictures in manual experimenting with settings to see what happens.
Empowered by a glass of wine, and a successful tutoring session with my daughter, I remembered an experiment I used when I was first taking up camera-
Depth of field- (as mentioned by RWebb)
I whipped out my canon 50mm 1.2 lense tonight, placed a spare powershot as a subject(at 20 inches on the ruler). Next to it is a canister? of advil? Next to that is a ruler. At the end of the ruler ( zero inches) is a bottle of spray water to keep the dogs off the table. The 50mm canon lense / 5dmkIII(taking these pics) is at 36 inches at the end of the ruler.
Let's have some fun!
(and this sort of ties in to Zeke's 50 1.2 lense thread
)
Aperture 1.2 :
At 1.2 aperture, from my SLR, the depth of field is very shallow- It is a knife edge. Look at the ruler- it' in focus between 20-21.5? inches, if even that. So that's a narrow DOF. Hard to work in unless you want to be artistic or really specific. Also- the water bottle at zero inches (background) is total blurr. Some of the brass pics earlier suffer from such a shallow DOF that they aren't in full focus.
Edit- also notice how clean my wife's table cloth is in front of the powershot camera... more on this later...
So let's back it off to 2.8 aperture:
Now the camera powershot is in focus, and the advil container is getting more in focus too. Look at the ruler- 19-22? (approx?) The DOF is increasing. Water bottle in background- still blurry, but you can sort of make it out against the chair back.
Now f 8.0
now the ruler is 18- 25? (I can't remember- and not going back to check)- The water bottle in distance is almost in focus.
Now f 22?
Now, almost whole ruler in focus. Water bottle in distance almost in focus, DOF even bigger.....
edit- aw crap, so are crumbs on table.
edit... and you can almost see my wife's "
beautiful awesomely blue wallpaper choice" in the kitchen also...
"It's wonderful honey.."
The point being, go lock yourself in a closet or something and play with the settings to see how these functions affect the picture quality. Takes 100's of experimental pics. go have fun. This is a good way to learn what the settings do. Isolate each element- aperture, exposure, ISO, timing, etc.. .see what they do.
The good news with static product shots is that you are on a tripod, with a remote shutter release (get a remote release, or a tether into a computer, or worst case scenario, use 5 or 10 second delay if you are using camera button to take pics) so timing doesn't depend on camera stability or subject movement,- therefore you can concentrate on DOF and exposure more.
Have fun!