Question 1

Well to take a quality photograph in low-light conditions there are many factors to think about. Firstly It’s very important you expose long enough to get any data, especially with digital cameras that we have today you can expose and see more with that than your own eyes.

So when you find something to photograph depending on the lights you have at the moment, different exposure settings are important. Longer exposure=more light hitting the exposed camera sensor. You should expose enough to capture what you want but it’s a game of balance, depending on the subject and the environment. If you have a moving subject you’ll want to lower the shutter speed, (the time the sensor is exposed to the light.) But this will leave you with a darker image, then you can balance that by turning up your ISO.( Basically boosting the signal sent from your digital sensor).

But this will maybe leave you with a noisy and grainy image. So then maybe you decide to put on a wider lens with a lower aperture/ lower f-stop to let more light in to the sensor so you can lower the ISO and get rid of the noise and with a wider lens you don’t have to worry about camera shakes as much, a simple rule of thumb for when a lens is in danger of creating camera shakes is looking at the focal length let say it’s 100mm if you are shooting at a shutter speed of 1/100 or slower camera shakes from your hands are an issue. So that’s why if you have a wider lens for example 24mm you can shoot hand held relatively safe all the way down to 1/24 of a second. This also varies depending of the built in stabilizers and other methods, it also only concern camera shakes, so depending of how much the object you’re trying to photograph is moving is also going to make a difference as well.

But changing the lens might give you a depth of field that’s to shallow for what you want. You could perhaps get around this depth of field problem by changing back to a more zoomed in lens and use a tripod. This would take the camera shakes out of the equation.

White balance (the process of calibrating the camera depending on the light to get the accurate color and color temperature).

A problem you might run into during night photography is the color temperature.
As with your own eyes color gets harder to see the darker it gets, the camera have the same issue even though a camera is often better than our eyes at that when it gets dark the cameras white balance mechanism struggles to get it accurate, often you end up with warmer lights and color temperature than what it is, so if you need to get the correct color temperature you need to manually white balance your shots, or shoot in RAW which lets you edit white balance after the fact.