How to choose the right camera


Understanding Exposure

So let’s start with the very basics of photography: The Exposure Triangle. Being a triangle, it has three major sections to it that are the foundation to all photography. Aperture, shutter speed, and ISO. If you understand the three of these things and how they affect light, then you’ll already know 90% of what you need to be a good photographer.

Photography is all about light, of course. Exposure means “how much light am I receiving to work with?” And the Exposure Triangle is all about controlling the flow of that light!

Understanding Exposure Part I: Aperture

Aperture is a lot more complicating sounding than it is. It’s actually quite easy to understand once you play with it a bit. An aperture is a hole that you look through. So aperture in photography is controlling the size of the peep-hole that light enters the lens through.

Once light enters through the glass and aperture hole it hits the sensor. And how big or small that hole is controls a lot of things about your photography. It controls how much light hits the camera’s image sensor, for one. All three of these factors, aperture, shutter speed, and ISO, control light levels on the camera sensor. Aperture is just the most obvious one.

If you think of an eye, the aperture would be the pupil. When the pupil is narrow in bright light, it’s keeping light from flooding the retina. That’s aperture and as a photographer, I can do the same thing to keep light from flooding my sensor.

Aperture is written as f/numbers. Don’t ask me what the f/stands for; it’s just an expression carried over from film photography. And contrary to logic, the bigger the f/number the SMALLER the aperture hole is for light to enter.

If I see f/1.4 I know that the aperture is wide open and light is pouring in. If I’m shooting a wedding in a dark church a number like this is perfect. If I set my camera to f/11 or more, the hole is much smaller and very little light can enter.

So why would I ever want to make the number smaller if I want light as a photographer? Well, aperture has a second effect that’s just as important as light control. When I narrow my aperture I control what’s called depth of field.

Depth of field is how much of a scene is in sharp focus. If you’re a fan of portrait photos, then you’ve seen lots of images where the person is in sharp focus but the background is blurred out. In those photos, we’re using a narrow depth of field. In a landscape photo where both the foreground meadow and background mountains are in sharp focus I’m using a wide depth of field.

For the portrait I used a wide open aperture like f/1.4 to create a narrow depth of field. For a landscape scene I’d use f/11 or more to ensure everything’s nice and sharply focused.

Understanding Exposure Part II: Shutter Speed

Shutter speed isn’t complicated, either. If the aperture is the pupil, then shutter speed is the eyelids. How fast they blink is shutter speed. That’s it!

If I use a fast shutter speed, then only a little light enters to hit the sensor which makes a darker photograph. If I use a slow shutter speed, then more light can strike the sensor.

But just like aperture, shutter speed also has a secondary effect. It controls the flow of motion in an image. By using a fast shutter speed, I can freeze the action. Fast cars racing around a track become blurred if I use a slow (or low) shutter speed but frozen when using a fast (or high) one.

Understanding Exposure Part III: ISO

ISO is the third part of the Exposure Triangle. It has a primary and secondary effect, just like aperture and shutter speed. Using the eyeball analogy again the ISO setting might be the sensitivity of the retina to light.

If you’ve ever used a film camera, then you know that camera film has ISO ratings. They come in numbers like ISO 200 and go higher from there. The ISO number determines how sensitive the film is to light. The higher the number, the more sensitive the film, which lets me use it in darker and darker scenes.

If I’m shooting in the middle of a field in broad daylight, I probably only need basic sensitivity, like ISO 200 (many cameras can go even further to ISO 100 or 50). But if it’s a cloudy day or I’m shooting in shade I might want to use ISO 400 instead. And as the sun goes down the numbers need to creep higher. At night I’ll be using at least ISO 6400 or more, depending on the scene.

So again, the same question as before. We want as much light as possible, right? So why not keep the ISO as high as possible all the time? Because of the secondary effects.

The secondary effect of ISO is noise control. So what is noise? Noise is pixelated artifacts that come up as errors in an image. They look like colored static in the photograph because that’s exactly what they are.

As you crank up the camera sensor’s sensitivity it’s much easier for the pixels of the sensor to get triggered by extra scattered light that isn’t of use for a photograph. Heat and electrons in the body of the camera can also cause noise to come up.

So we want to make sure our sensitivity is high enough that our image looks nicely lit but not so high that noise starts making the photo look bad. ISO is the setting you’ll adjust the least often on an interchangeable lens camera. Usually you’ll be changing your aperture or shutter speed.

But because shutter speed and aperture have such dramatic secondary effects on composition sometimes it’s better to just change the ISO value. If I really want to freeze the action on a fast moving car while keeping the background nice and blurred, I can’t adjust my shutter speed or my aperture. My best choice of Exposure Triangle options is to raise or lower the ISO value as needed.

So play with these three concepts because they’re foundational to photography. If you can master the Exposure Triangle you’re well on your way to mastering the rest.

Composition 101

Composition is a little more challenging because there are rules about composing a good photo and those rules are also meant to be broken as needed. Composition is about creating good art. So what is good art in photography? Well, it’s the art you like, just like any other art!

But there are a few agreed-upon rules that are worth looking at. One of those is The Rule of Thirds.

Imagine four lines of equal distance, two going horizontally across a scene and two vertically. That’s essentially the Rule of Thirds right there. The image is broken up into nine sections that are the same size.

The idea is to align subjects either along the lines or at the intersections of those lines for maximum impact. The Rule of Thirds adds a pleasing symmetry to landscape and architecture images and a sense of impact to portraits. It’s hard to describe unless you’re looking at two photos of the same subject, one using it and one without. The vast majority of people will prefer the image composed using the Rule of Thirds.

Many cameras today even come with a setting you can turn on that creates a Rule of Thirds grid over your viewfinder. And some optical viewfinders have it built in. That’s how important the concept is to photography! It sounds simple because it is yet the effect is tremendous.

There are other rules as well, like Leading Lines and the Golden Ratio, that will vastly improve your photography. But start with this one and watch how much your images improve just by keeping the grid in mind!

Choosing the right camera and lenses

If I’m going to be shooting a lot of portraits, then I need lenses that open as wide as possible. Unfortunately, those tend to be the most expensive because there’s more moving parts involved. And if you want a zoom lens that also opens wide, well, those are the most expensive of all.

So what’s “wide” in photography? Anything below f/3 in most situations could be considered a wide aperture. But again, it depends on what you’re shooting and the available light levels. The kit lens that came with your camera probably doesn’t open this wide. They usually say something like “18-55mm f/3.5-5.6.” This means that at 18mm the lens can open as wide as f/3.5 while at 55mm the maximum aperture is f/5.6. That means I’ll need to invest in some good glass if I want to take portraits! But that’s the fun of using an interchangeable lens camera.

What if my camera doesn’t let me change out the lenses?

Then you’re stuck with whatever aperture settings it has. Sometimes you can change them and sometimes you can’t. Cameras like that are called “point and shoot” because there’s less to gear and settings to fiddle with.

Funnily enough the camera body is actually not nearly as important as the lenses. Lenses hold their value and because you’ll be buying so many (and probably for a good amount of money) you want to make sure you’re happy with the brand and quality of them.

Camera bodies can last upwards of 10 years and the only thing that will probably need replacing is the shutter if you’re careful. But every year they add new features and you’ll probably decide to “upgrade” way before then.

But even if you decide to upgrade your lenses will remain perfectly usable with your camera. Manufacturers also rarely add a ton of lens features compared to what they cram into camera bodies. Some like Canon and Nikon have lenses over 20 years old that still work as well as lenses made last year.

But that doesn’t mean you should cheap out on the body, either. Try to strike a balance between features and price. Do you want 4K video or is Full HD video enough for you? How many megapixels of resolution do you need? Image stabilization? Weather sealing? Fast autofocus with tons of focus points? Or a more basic autofocus but larger sensor? There’s always going to be a trade-off and you’re not going to find the perfect camera body.

Megapixels are worth talking about, though, because of how important everyone thinks they are. People usually think that the more megapixels you have, the better. This is not at all true. If you’re blowing up your prints for posters and billboard displays, then you need as many as you can get to keep your images looking sharp.

But most of us are just posting on blogs and Facebook, maybe a personal gallery. So how many megapixels do you need for that? 16 megapixels gives you plenty of resolution while still giving you room to crop a photo a little as needed. And 12 gives you great looking photos as long as you don’t crop it further.

Most cameras on the market today give around 20-24 megapixels, which is more than enough for 95% of the photographers out there. So when the salesperson points you in the direction of the 36-42 megapixel monsters, remember that unless you’re already a professional (and wouldn’t be reading this anyway), you’re just not going to use that amount.


So I’ve done my best to condense all that I know about photography into an easy to digest guide! There’s still a lot to chew on for you but not so much to be intimidating. We’ve covered the major types of photography, elements of exposure, basic composition, and some thoughts on gear selection.

If you only have time to read one section, I suggest you skip straight to Understanding Exposure. But I hope you’ll read it all. And even if you don’t, like any art, most of this you’ll learn on the fly anyways, so get out there and start shooting, already!