My first little tutorial is simply on shutter speed, aperture, and ISO. These are probably the three most important things you need to understand about your camera and all three can affect each other. If you want to take good photos and have control of your results, you need to get off that camera auto mode or scene modes and strictly use the manual modes.
Shutter speed is pretty simple, imagine your shutter is like a curtain on a stage and there is this amazing background(your photograph), it has to open and expose your stage with light to see it. Shutters expose the sensor with light, sort of like opening the curtain would the stage. If you have a super fast shutter speed like 1/2000 of second, the shutter open and closes super fast and exposes the photo with very little light. A couple things happen here, one you need more light to expose the photo properly, and two, at this speed you can freeze movement or action of anything. At a 3 second shutter speed, your camera opens the shutter for that length of time, allowing light to flood in for a full 3 seconds. This way you need much less light to expose the photo properly but subjects will definitely blur if they move, You also need a tripod to prevent camera shake in those long shutter speeds.
Fast Shutter = Freezing action, less light hitting the sensor.
Slow Shutter = Motion Blur, collects more light on sensor
ISO is that number you might have seen on film before you had a digital camera, 100, 200, and 400 were all pretty standard. Your camera has the same thing. ISO is hard to describe, I would say it's kind of like a sponge, as you turn it up to say ISO 3200, your camera is going to soak up more light, but at the cost of quality, things like grain and noise start to be introduced at high ISO's. If you shoot at ISO 100, your image is gonna be much smoother and have lower noise like less porous sponge, that in mind, the sponge isn't going to soak up as much light.
Larger ISO = more exposure and light, more grain and noise
Smaller ISO = less exposure and light, less grain and noise
Aperture is that number you see on your lens. Some may say f/2.8 or f/3.5-5.6. Aperture is actually a function of your lens, but greatly affects your camera. You can see the aperture in many lenses just by looking inside. They almost look like blades overlapping to make a circle in the center and that is what your camera looks through to take the photograph. Now some people get confused at this point because you would think a larger aperture would be a bigger number but it's the exact opposite. The lower the number the larger the aperture, meaning the closer you get to zero, the bigger the hole which allows more light in. The larger the aperture number the smaller the aperture hole is open, smaller hole = less light in. Now when you have a lens that says f2.8, it means the aperture will open as large as 2.8, which will allow more light in than say a f/3.5. If this is a zoom lens it means you entire zoom range will be able to shoot at aperture 2.8. When a lens say something like f/3.5-5.6, it means that as you zoom your lens, the largest aperture available becomes smaller. So say you have a 18-200mm lens. At 18mm your biggest aperture is 3.5, but as you zoom out it gets smaller and smaller till you hit 200mm and your largest aperture is now 5.6 which means you need more light to properly expose the photo than you did at 18mm. So in short, shooting at f/2.8 will be a large aperture allowing more light into the camera, at f/18, the aperture will be much smaller and the light allowed inside with be significantly less. Aperture affects one more important factor of your photo, depth of field. When you shoot at f/2.8, a very large aperture, your photo will blur very quickly from your focused subject. As you zoom in, it intensifies it. At a small aperture like f/18, your overall photo will be much more in focus throughout the frame, and the blurring effect will be considerable diminished.
Larger Aperture = lower F number, shallow depth of field, frame blurs quickly from focus point
Smaller Aperture = higher F number, wide depth of field, more of the frame stays sharp from focus point
How does each affect the other. Let's say you are taking a photo of a street in broad daylight and it's very bright. You want to capture cars driving by. So you start with an ISO 100, shutter speed 1/50 of a second, and an aperture of 3.5. You take the pic and exposure is perfect but the car driving is blurred. So you need to up the shutter speed to say 1/500 of second cause the faster it is the better is freezes subjects. Now you are letting less light in, so to get the same exposure you need to either A) turn up your ISO or B)open your aperture larger. Maybe 3.5 is your biggest aperture, so you have to turn up your ISO to 800, take another pic and that should get it close to the original exposure but now your car isn't blurred.
A second example, let's say you got the same car shot at ISO 1600, shutter 1/500 of a second, and an aperture of 3.5. It's perfect exposure but maybe you want the car to blur this time to see movement. You know you got to slow the shutter speed. Let's try 1 second. Take the pic, now everything is overexposed. It's cause you let more light in at one second than you did at 1/500. Again you can change the ISO or the aperture. So we change ISO and knock it down to 200. Now the image is clearer with less noise thanks to the lower ISO and it soaks up less light bringing the exposure back down to your original perfect photo. But wait, the background is also blurred a lot due to the 3.5 aperture. Let's say I want the building in the back to be in focus as well. I need a smaller aperture. So make the aperture smaller by going up in number. I set it at 13. Take the pic, now it's underexposed because the smaller aperture let's less light in on the sensor. So, we go back to the ISO and turn it back up to 1600 and now we have a properly expose photo, with a blurred car and an in focus building in the background.
These numbers are not exact, I didn't measure the stops or test any photos, it's just for reference so you get an idea of what you can do. The best thing is sit somewhere and take photos. Change these settings and look at the photo and you immediately start to see what effect it has on your picture.
Some general photography tips. If you are shooting action, I will use shutter priority a lot, and maybe turn the ISO up to 800. Not much noise will come from new cameras at this ISO and it allows my camera more flexibility when choosing an aperture. Then you can set your camera to say 1/1600 of a second, which is real fast and creates that frozen movement. In this mode your camera will adjust the aperture automatically with changing conditions. Sometimes full manual takes to much time and you might miss that great shot.
Aperture priority is great for landscape and city photography. Generally you want a smaller aperture so more of the picture stays in focus. At an aperture of f/2.8, basically only the point you focus on will be real sharp and the rest of the landscape or city will be blurred. Which is also okay if that's what you are going for. But normally if you want everything sharp and crisp, set it on aperture priority and bump it up to say f/18. Then your camera will adjust the shutter speed needed to properly expose the photo, and the small aperture will keep more things in focus.
Full Manual Mode. the best, you have full control over your depth of field via the aperture, your shutter speed, and ISO. You can fine tune your pics this way and make them exactly what you want. This is my most used setting but those other priority modes come in handy.
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