Exposure Triangle
Exposure is the amount of light that hits your sensor.
Lots of good articles. Here’s one: https://photographylife.com/what-is-exposure
The exposure triangle are 3 settings that all interact to give you a “properly exposed” photo:
- Shutter speed
- Aperture
- ISO sensitivity
According to this article:
https://visualwilderness.com/fieldwork/reason-change-iso-in-photography
You should just keep you ISO setting at the lowest and vary the other two settings. The article says that you should only change your ISO when you’re targeting a particular shutter speed. Higher ISO sensitivity tends to increase noise.
Remember that exposure is about how much light reaches your film. Technically, ISO sensitivity isn’t really about that. So really we have shutter speed and aperture.
Shutter Speed
Exposure is about how much light reaches your film. Technically, ISO sensitivity isn’t really about that. So really we have shutter speed and aperture.
Shutter Speed is measured in time. It’s the amount of time the camera spends taking the photo. More time means more light coming in. Too long and the photo is over exposed. Too short and it’s under-exposed.
Shutter speed is also about motion. Small exposure means you have a better chance of capturing a fast moving object. In particular, zooming in magnifies speed, and you’ll want a smaller shutter speed for a fast moving object.
From the above article, quick and dirty guideline:
Want a quick-and-dirty guideline? Use 1/500 second or faster for sports and wildlife action. Use 1/100 second or faster for telephoto portrait images. Use 1/50 second or faster for wider-angle portrait or travel photos where your subject isn’t moving too much. If your subject is completely still, and you have a tripod, use any shutter speed you want.
Aperture
This is the size of the hole that lets the light in. It’s measured as a fraction, f/N. So f/2 is a bigger aperture than f/16, i.e. it lets more light in.
Aperture controls exposure and depth of field. Exposure is the amount of light you let in. Field of depth controls how much of your image appears sharp.
Small apertures (f/11, f/16) give you a large field of depth, which will make your entire photo, front to back, appear sharp. Use this for landscape photos. Remember that this lets less light in, though (less exposure). Counteract will longer shutter speed (though you may need a tripod at some point).
Large apertures (f/1.4 or f/2.8) give you a thin Depth of field and will give a shallow focus effect, good if you’re trying to make “zero in” on one part of the photo. Remember that this let’s more light in, though (more exposure). Counteract with smaller shutter speed.