The basics in photography really revolve around three key features on any camera that effect eachother almost in a triangle. Changing one will affect the other two in a way that alters the photo, sometimes quite negatively. These three camera performances are known as ISO, shutter speed and aperture or "f/stops". I will go into more detail what each mean and what they actually do. I do want to mention however that no matter how well you balance each of these you simply cannot take a photo without light. And this is where I will mention the oftentimes overlooked and equally important feature known as your light meter, which all cameras possess including the most basic point-and-shoots.
Before going into camera functions I would like to take a moment to talk about megapixels, a feature often used to sell people on buying more expensive cameras than necessary. Megapixels do not directly effect the quality of a photo in its digital form. You will almost never notice a difference between a picture on facebook taken with a camera that has 10 megapixels and one that has 21 megapixels. You WILL notice a difference when the image is professionally edited to enhance sharpness. Stores often use megapixels as a selling point that one camera is better than the other because it has more. Megapixels are used simply to create better prints. I'm not referring to 8x10s for your wedding album, I'm talking about a photo that is 3 ft x 4 ft or much larger. In other words, the more megapixels you have the more you can afford to blow up an image on your wall. This is why professional cameras have at least 21 megapixels, newer ones reaching even 36.
ISO is a relatively important function to know, and when I say that I mean it's relative to the situation you are in. The digital world today sort of aged out what ISO really means and what it used to do on film cameras of old and it plays a less important role now. ISO simply refers to the sensativity of light on your sensor. The higher the ISO number the brighter the image will be.... with a cost. ISO also generates heat on your sensor called NOISE. Noise is the visual representation of heat and it's often referred to as that "static" in a poorly constructed image. Image noise can destroy individual pixels beyond repair and can essentially ruin parts of images. Almost every single one of my images on my website is taken with an ISO of 100, the starting level. In fact I change ISO so rarely it's the one button on my camera I can't find blindfolded. So why worry about ISO at all then? Well photographers who need to "up the anty" change ISO because they are shooting star trails or indoor nighttime photography. Because it increases the sensativity of light, these dimly lit subjects will now become more visible and it will allow you to have a smaller shutter speed or narrower aperture, something vital for star trails. See how this is already altering shutter speed and aperture? Most photographers shouldn't worry about ISO if they are doing anything with sunlight or studio lighting, there are other more effective ways of letting light onto your sensor without gathering image noise. ISO on film cameras refers to the speed of the individual film strips. These are often referred to as ISO 100, 200, 300 etc. It essentially does the same thing, however played a more vital role on film cameras.
Aperture literally means the opening in your lens hole that affects the angle of light hitting your sensor. Aperture is commonly referenced as "f/stops" on lenses. You've probably seen this as f/4 or f/2.5. That number is talking about the speed of your lens focusing but it also refers to the lowest f/stop (or largest hole) available on that lens. So if I took an image with an aperture of f/16 I'm talking about the size of the opening in the lens to let light in. This is where it gets confusing for some people. Try to follow...... the higher the "f/stop" number, the smaller (or narrower) the hole. The smaller the "f/stop" number, the larger the opening in the lens will be. So if you have a lens that is an f/4 lens and you take an image with an aperture of f/4 then you opened the hole in your lens to its maximum size to let the most amount of light in. However, this also doesn't come without consequence. The larger the hole in your lens (or smaller the f/stop), the less depth of field you will have. That is how those wedding photographers get very shallow photos where only maybe the bride and groom are in focus and the background is a blur. Inversely, the smaller the hole in your lens (or larger the f/stop), the more depth of field you will have in your image. This is where landscape photographers thrive. We set our f/stop to its maximum, for instance on my lens it is f/22, which is a very tiny hole. It keeps the photo evenly in focus. Aperture is mainly used and altered by wedding or portrait photographers. This is their creative setting allowing them to achieve different results while maintaining a quick shutter speed and low ISO. Seeing the trend already?
Shutter speed is by far my favorite setting to alter, and for good reason. This is the camera function that landscape photographers use as their creative setting. By changing this it allows us to achieve slow milky rivers, streams or clouds. It also allows us to capture quickly falling leaves or wildlife. Shutter speed is referring to how long you leave the shutter mirror open to reveal your sensor to light. If you've ever looked inside a camera you know that your sensor is protected by a mirror or "shutter" door which is what is reflected into your viewfinder. When you take the photo this door swings up (making that distinctive noise) revealing your sensor to whatever lighting conditions you set. This speed is what dictates how long that door is opened. You've probably seen shutter speed referred to as "1/500" or "1/125". This simply means 1/500th of a second or 1/125th of a second. While it may not seem like a significant difference between that little amount of time the amount of light that can hit your sensor can be a lot. Your camera's sensor is so ultra-sensative to light (it's the reason your cameras are so expensive!) that almost ANY change in time can affect an image quite drastically. These faster shutter speeds (such as 1/1000) are what wildlife photographers or sports photographers use to achieve literally "frozen in time" moments. Landscape photographers use the reverse of these settings most often. We like to play in the "5/1" or "0.5/1", however in photography it's not referred as this. It's simply labeled as "2"5s" or "5"s" meaning it was a 2 and a half second exposure or 5 second exposure. Most cameras will allow you to take 30 second exposures without having to hold down the shutter button. However if you want to do anything over you need to switch over to your camera's bulb mode. The longest exposure I've taken was my image "City of Black and White" which was a 5 minute exposure. Star trails were even forming at the top through the city lights. Shutter speed is usually the easiest concept to grasp however it also doesn't come without consequence. Image noise is often it's common adversary. Light = heat and because the sensor is taking on enormous amounts of light it is building up all that heat causing noise. This is why having the lowest possible ISO will help to negate some of that heat. I think by now you can understand the triangular effect ISO, shutter speed and aperture all have on eachother.
An image I took over 4 years ago while still learning the effects an open shutter has on moving subjects. These are the stairs at the Salk Institute of UCSD.
This leads me into the fourth element of a photo ---> light. Light is the fundamental principle of all images. Without any kind of light you simply don't have an image. While you may not need a whole lot of light to take a great image on today's sensors, throwing your camera in a closet and turning off all the lights at night doesn't exactly help your cause. The light meter is a common tool overlooked by even a lot of advanced photographers. I myself didn't fully grasp the concept of the light meter until the last couple of years. The light meter is the basis for a lot of my editing techniques in photoshop and it's the tool that let's me know what kind of image I'll be able to take and what I can do with it. All cameras use a light-meter to judge how evenly exposed the image is. So even if the only button you know on your camera is the on/off you still use a light meter. When your camera beeps at you that it's in focus it also just took a reading of the light to tell you it's an evenly exposed image.
On advanced cameras and DSLR's the light meter is an actual meter in your viewfinder as well as your top screen. This meter is that line which has " -2..-1..0..+1..+2". Right beneath it is a vertical line telling you what number it's on. These numbers are referring to the stops of light over or under exposed the image is BASED ON WHAT YOU ARE POINTING AT. I can't stress this enough. The camera doesn't take a reading of the overall image, it takes a reading of what kind of light you are aiming at. There is a way to do this but I won't go into that. So if my vertical line is underneath the "-2" that means my image is 2 stops under-exposed and I need to do something or alter a setting that will bring it back to 0 or whichever stop of light I desire. After doing this for many years you subconciously know how exposed you want the image to be and it becomes second nature to react to light. However when new you will oftentimes stop and think "oh, I may need to open my aperture by 2 stops to let 2 stops of light in to bring it back to 0" or "hey I need to put a 2-stop filter on my lens to bring my light back down to 0" etc.
Remember how I said the light-meter is the basis for a lot of my editing techniques? Well when taking multiple photos and blending them together I need to know how well each image is exposed to achieve my results. The light meter is the only way to tell. I will eventually create an advanced editing guide on manual blending and the process I go through.
You may be thinking why should I care if my sensor is cropped, let alone the effect it has on the zoom length of my lens? Instead this question has probably never crossed your mind. That's because it's a hidden fact most consumers don't know. If you are a starting photographer or hobbyist chances are you use a cropped sensor. Almost all consumer model DSLR's (Canons, Nikons, Pentax's etc.) use a sensor that is cropped based on a "1.6" multiplier formula. Companies do this to cut the cost on cameras to make them more available to the general public (because sensors are what creates value on your camera). This means that you are not using your actual focal length on your lens, a huge consequence for professionals. **WARNING, MATH AHEAD** Let's say you are using a lens with a focal length of 16-35mm and you have it on a camera with a 1.6 cropped sensor. To find out what focal length you are actually using you simply multiply 16 x 1.6= 25.6 and 35 x 1.6= 56. So in reality you are using a lens with a focal length of 26-56mm, a signifcant difference in image width. However companies assume that people who use these cameras won't mind because they aren't taking images that require perfection, allowing more expensive (yet reasonably priced) cameras to be sold to consumers. THIS, is why professionals spend the money they do on camera bodies alone.
Full-framed sensors, such as the one on my Canon 5D mark ii are very costly, however the results are unachievable with any camera but a full-framed sensor. This I know because I've performed test shots with my old Canon 40D 1.6 cropped sensor against my full-framed sensor and the differences in the amount of light were..... astounding. I also get to use my full lens focal length which is vital for professional images. However because of how detailed full-framed sensors are, they require only the best lens elements to focus light onto it. Another marketing ploy by companies. Camera companies get to sell cheaper lenses on cropped sensors because they don't require higher end elements. Anybody who has used film cameras understands this concept because of the old full-framed cameras, however because it's digital it's more expensive.
I hope this starter tutorial was informative to anyone. These are the basic basics, as down and dirty as it gets. I will slowly build upon each concept from the last and branch off on editing tutorials from these. I will not tell you HOW to take an image, only present you with the information so that you can apply them in your own right. I believe this is the best way to learn.
Ultimately photography takes patience, lots of practice and even more failure. These are the concepts I have taught myself throughout the years and they are by no means THE WAY. In fact some of these "facts" may not hold true from photographer to photographer, they are just the facts that have allowed me to take the photos I take. I build upon my experiences and learn from the past to understand the future. Classrooms cannot teach you photography, they can only teach you cameras, editing and techniques. To truly understand photography it is taught from within you. Thanks again and let me know if you found anything confusing that you would like me to explain further.
Welcome to my blog. I am a fine art landscape photographer living on the west coast of the United States. Here you can keep track on my upcoming/current events, projects, trips or simply read up on some tutorials!