I have a Canon Powershot A700 and would like to be able to take photos similar in quality to ones like this from Gdad:
and WDWFigment:
Any tips on what settings I should use?
Unfortunately, your camera is just not quite able to do as well in handheld low light situations as theirs. Though obviously photographers of high talent, and certainly a large part of their beautiful photos has to do with the photographer, it must be said that the tool does still make a difference, especially when dealing with low light.
If you take photos using a tripod, using your lowest ISO and a longer shutter, you can get photos of that quality. But in order to shoot like this handheld, you would need to use a much higher ISO to get a short enough shutter speed to not get camera shake...and at higher ISOs, your camera will get much more grainy and noisy and begin to lose details.
By no means is your camera bad - it's just fine for 90% of the normal photographic situations most people find themselves in...but getting into handheld low light photography would most likely require stepping up to a much larger sensor and much more sensitive lens. Stick with a tripod, level surface, garbage can, etc...and use a slow shutter...and your camera can take beautiful night shots similar to those. Want to take shots like that handheld, start looking into DSLRs and good, low light lenses in the F1.4-2.0 range!
On a related note, I haven't been able to figure out how to focus manually on a particular object so that only the object is perfectly focused while the background is out of focus, like in this this other photo from Gdad:
Again...your camera will limit your control over shots like this. it's not impossible - it will just take alot more work, and likely require some more distance than in the shot example you showed. Shallow depth of field is the factor that makes this effect possible...large sensor DSLR cameras tend to have extremely narrow depth of field with larger apertures - meaning if you focus on a certain point, the out-of-focus area will begin just inches in front of and behind that focus point. Zoom in on a subject with a zoom lens, and that depth of field can become even narrower. When you want to increase the depth of field, you go to a smaller aperture (bigger F-number).
With a P&S camera, the sensor is extremely small, as is the lens, and even at the most wide-open aperture, the depth of field is quite large...you might focus on a certain point, and have several feet in front or in back of the subject still within focus...or even more. It can become quite hard to get something OUT of focus in fact! Your best chance with a P&S camera to get the background out of focus while leaving the foreground subject in focus is to make sure the camera is set to the widest aperture (smallest F-number...such as F2.8)...stand farther back from your intended subject, and use your optical zoom lens to zoom in on it, and try to pick a subject that is farther away from the background. The more distance, the better...if you can stand 20 feet away, zoom in on an object, and have the background be 15-20 feet away, you can get the intended effect...as long as the aperture is fully opened.
P&S cameras with much bigger zooms can do this easier than yours...with all of that zoom to deal with, you can stand 30-50 feet or more from a subject, and use the zoom to make it look like you are standing just a few feet away, which can help to enhance the out-of-focus effect. But with a compact 3x zoom camera, you'll need to try to get as much distance as possible between you and your subject, and your subject and the background.
(BTW - that wide depth of field is an advantage for most consumers with P&S cameras - many people who get into DSLRs without much photographic skill or knowledge can struggle nailing the focus, because of that extremely narrow depth-of-field that they aren't used to - sometimes a DSLR might be focused just an inch or two off the intended area, and cause the subject to be blurry and out of focus...if they don't know how to properly focus, or to reduce the aperture to compensate, they can get very frustrated with their cameras. Though you can't easily achieve the very cool effects with a compact camera that a good photographer can with a DSLR, most people at least can get good focused shots with their P&S cameras even without alot of skill or knowledge of photography).