My camera takes great pictures in most lighting situations, but I get blurry and/or noisy photos when there's not a lot of light. Do you know how I can take better low-light photos without spending a bunch of money?
Sincerely, Shooting In the DarkMusic by Gold'n Teasdale
Check out the video above if you don't like to read, and it'll explain everything I'm about to get into. If you do like to read, then keep reading!
There are a bunch of things you can do if you want to improve your low light photography, even if you don't have a fancy DSLR. Since you didn't specify, we'll talk about both.
Get a Fast Lens
A fast lens refers to a lens with a wide aperture. The wider your aperture, the more light it lets in, so that's good if you don't have much light. The downside of a wide aperture — which may be an upside in some situations — is that you have a very shallow depth of field. This is great if you want a shallow depth of field, but it means that you can end up with photos that are easily out of focus if you're not careful. If you're using a point and shoot, this isn't a very helpful tip because your lens is attached — you can't buy a faster one. If you're using a DSLR, however, faster lenses are easy to come by and you can pick them up on the cheap. The cheapest lens for pretty much any DSLR is a 50mm prime lens (prime basically means that it doesn't zoom). You can generally find these for under $US100 with an aperture of f/1.8. Aperture is rated by f-stops, and the lower that number is the wider the aperture. In most cases, an aperture of f/1.8 is as wide as you want to go because f/1.8 at 50mm provides a very shallow depth of field. You'll let in plenty of light this way and can get some beautiful photos in low-light conditions.
Reduce Your Shutter Speed
When you take a picture, the camera's shutter opens and closes. The speed at which this happens is your shutter speed. The longer the shutter is open, the more light gets in. The longer the shutter is open, the more you'll see motion blur as well. Unless you want your subjects to be blurry, this is not really an option. If you're taking a landscape photo, however, and nothing is really moving around, a slow shutter speed is perfect. If you have plenty of light, you won't need to reduce your shutter speed, but if you're taking a landscape photo (or a photo of anything that doesn't move) at night you can afford to use a slower speed. Just make sure the camera is stabilised so it doesn't cause any unwanted motion blur as well.
Bump Up Your ISO
ISO is basically the digital equivalent of film speed, or how sensitive your sensor is to the light that hits it. The lower the ISO, the less sensitive your sensor is. You tend to get a more realistic representation of light at lower ISOs, but when you don't have a bunch of light you can easily solve that problem by letting your camera's sensor be a bit more sensitive to the light that you do have. Generally ISO 100 or 200 is good for outdoor photos with plenty of light, and ISO 400 or 800 will do the job indoors when you have less light. Many cameras have ISO ratings going up to 3200 or even higher. The higher you go the more your light will be blown out, but the disadvantage people worry about the most is the increased noise in your photos. High ISOs come with higher noise levels, which isn't terribly appealing. If you're printing small photos (4x6s or 5x7s) or just delivering to the web, however, the amount of noise isn't really going to show up too much and so it's nothing to worry about. Also, the better camera you have the less noise you'll get at higher ISOs. ISO 800 on your point and shoot might provide quite a bit of noise, but ISO 800 on your DSLR may have the appearance of no noise at all. To a large extent this has to do with the size of the sensor in your camera, but there are many other factors as well. For the most part, this is the easiest way to take low light photos with the fewest disadvantages.
Use Your Flash Effectively
Your flash will wash out your subject and create some harsh lighting effects, so nobody really likes to use it. Sometimes you have to, however, because the light you've got just doesn't cut it. If that's the case, you can diffuse the light pretty easily with some stuff you've got lying around. I like to make diffusion out of scotch tape or paper, which can be made to fit any camera's flash and be placed right over it, and will provide a softer and more pleasing light. You can also create a flash diffuser out of an empty cigarette packet, an old film cannister, craft foam, a drawer liner, or even a white plastic spoon.
Hopefully these tips will help you take better photos in low light. If you want to take a deeper dive into low light photography, Lisa Bettany's new show Mostly Photo has an episode on low light photography with several more tips and lots of detail.