Grats on taking up photography. I always found it therapeutic. The lens can really help slow the world around me down and force me to just see what's in front of my camera rather than pinging from one random thought to another. Please keep posting. My favorites of your shots are 1 and 5. nice focus, great composition (IMO).
To your focus question, you got 2 factors at play. Both revolve around the focal plane and the
depth of field before and after that focal plane. It can get quite "mathy" and you can find YouTube videos going into detail if you want to chase that.
As mentioned earlier, your
aperture setting is probably the most obvious factor. That's basically the gateway of your lens that determines how much light gets through into your camera. The lower this *aperture #, the
shallower your depth of field. As Citizen described, this can create a nice soft and blurry background to help pop your subject out. The trade-off is that you have a much
narrower depth of field that can be in focus. So for a real world example, you might use an aperture setting of f5.6 to get a small group (2-3) friends all in focus. However, an aperture setting of f1.8 (all other factors being the same, like distance, zoom, etc.) may only have one face in focus while the rest of the group is blurred out some, especially if the others are slightly in front of or behind the face you are focused on.
In addition to aperture, you have your zoom (
focal length in mm). How close you are physically to the subject will make your focus depth of field more or less shallow, too. The closer you are, the narrower your depth of field will be. The farther away from your subject, the deeper that depth of field becomes. That is probably why you had part of the subject out of focus while you were sitting close to it and more of it in focus the farther back to moved, even though you may have zoomed in.
[you]-----distance-----[start of focal range]----[subject focus]----[end of focal range]
[you]-----distance--------------[start of focal range]------------[subject focus]------------[end of focal range]
*I didn't want to include this earlier because it can get overwhelming. But the lower your aperture #, the larger that light gate is. For me, this was tricky to learn. The
lower the number, the
larger the aperture opening is, allowing
more light to enter the camera. If you then have more light hitting your sensor/film, then your exposure time can be much shorter to compensate. This is ideal for low light or action situations. Smaller apertures (f1-8 to f2.8) are wide open, letting more light through, giving you the option to use a higher shutter speed. The higher the shutter speed, the more likely you are to freeze the action you are shooting. Else, if the shutter speed is slower (as required buy an aperture of f5.6 to get enough like for a proper exposure), then the action may have motion blur if the shutter is open too long.
It's all this weird tricky 4-way sliding scale between zoom, aperture, shutter speed, and ISO! Each affecting the other slightly, one way or another. To see how this all affects your shot, maybe shoot in AV or TV mode. See what settings the camera chooses for a shot then try to manually recreate those settings. I did like you too--just jump in and sink or swim. But it does help to focus only one one setting while learning.
Very cool stuff! Keep posting please