Sometimes, you don't know what you're missing until someone shows you what's missing.
I became interested in photography when I was in high school. I checked out a few books from the public library trying to figure out how photography worked. I suppose I could have asked my dad. After all, he had a camera and he took pictures. So he must have known something. But during those long days of summer, picking up a book and reading it wasn't so bad.
What did I learn? Several things. First, film speed. If you buy film, it comes in a variety of speeds. 100, 200, 400, 800 and very rarely, 1600. Basically powers of 2 times one hundred. The bigger the number, the less time your shutter has to be open to take a photo for the same amount of light. What's a shutter?
Here's a quick lesson on photography. Light comes through the lens of a camera. When you click a button, a shutter (which is basically a door) lets the light in for a brief amount of time. The film gets exposed, which records the image that is going through the lens. The shutter can only open for a very short period of time. There are two reasons for this. If the shutter opens for too long, then the film gets too much light, and you get a white picture. No good.
Second, even if film could take that much light, you're trying to record a short moment in time. If a shutter stayed open for a few seconds, then any movement becomes blurry. Early photographs made during the Civil War had this problem. People had to stay still for many seconds, say, up to a minute, as the early versions of film required a great deal of light to record the image. It's also one reason you see few smiles in early photographs. It's hard to keep smiling for a minute.
Suppose it takes 1/10 of a second to take a photo with ISO 100 film (ISO is some international standard--don't worry what it means). Then, it takes 1/20 of a second with an ISO 200, 1/40 of a second with an ISO 400, 1/80 of a second with ISO 800, and so forth. With each doubling of the ISO number, you only need half as much time as the previous film speed. Needless to say, high ISO film speeds are good for fast moving subjects, such as photographing sports.
You might ask yourself, why shouldn't you buy the fastest speed film possible? There are two reasons. Cost and picture quality. The faster the speed, the more expensive the film costs. Now, usually ISO 100 and 200s are similar in cost, and ISO 400 is somewhat more pricey, but beyond that, it's expensive. Furthermore, faster speed films are grainier. When you develop film, it's basically a bunch of dots. Normally, they're too small to be noticed. However, the grainier the film, the more noticeable the size of the dots. Some photographers use this effect to create more immediacy in their photographs.
The next consideration for a film camera is how much work it does for you. My first camera was a low-end Nikon SLR. An SLR stands for "single lens reflex". Basically, the camera works like this. The light goes through a lens. In the camera, there's a mirror, which angles the light through a prism, and eventually through a viewfinder. You have to put your eye close to the camera to see the photo you're taking.
When you take a picture, the mirror, moves out of the way, the shutter opens very briefly, the film is exposed, then the shutter closes, and the mirror goes back up. This is why, when you look through a camera's viewfinder and take a picture, it gets briefly dark. An SLR has the advantage that you can see exactly what you're going to photograph, and adjust the focus.
Cheaper non-SLR cameras used a viewfinder that's similar to a shooting sight in a rifle. A rifle sometimes has a sight, that's basically a binocular. You look in it to help you line up what you are going to shoot. The problem with this viewfinder is that it does not go through the lens of your camera. It goes through a separate lens. It suffers from two problems: focus and parallax. Since you're not looking through the lens (TTL), but instead through something near the lens, it may not accurately give you the same picture as what you take. It'll be quite close, of course, but perhaps not as exact. Focusing can be more of an issue too.
Early cameras required you to do three things. Focus. Pick a shutter speed. Pick an aperture. Think about your eye. Your eye has an iris. This is a hole in your eye, that grows bigger if it's dark to let in more light, and smaller if there's plenty of light. Ever wonder why, after watching a movie in a dark room, that your eyes hurt when the lights come on? It's because your iris is opened up to watch the film. When the light comes on, too much light gets on the retina, and it hurts. Eventually, the iris adjust by shrinking, so you don't get as much light.
A camera's aperture works pretty much the same way. If the aperture is open wide, more light comes in per unit time. If it's small, less light comes in. Now, you might wonder why you wouldn't open the aperture wide all the time. After all, if it's open wide, the shutter doesn't need to be on nearly as long. To give an analogy, think of the aperture as how far you move the faucet on. The more you turn, the more water that pours out, the less time that's need to fill your cup. The less you turn, the less water that comes out, the more time to fill your cup.
Thus, picking an aperture (the size of the hole to let light in), and the shutter speed (the amount of time you open the hole to let light go from lens to film) are interrelated.
There's an important reason that you may want the aperture to be smaller. The more you open the aperture, the less range the camera is in focus. You may not notice this about your eyes, because it rapidly focuses, but when you focus on something close to you, you can't see the distant things clearly. The camera behaves the same way. If you're a few inches from the subject, then it's in perfect focus, then things further away are blurry. The closer you are, the more exaggerated this effect. In general, once the subject is about fifty feet away, then if it's in focus, then everything from that point back is in focus.
The wider the aperture (ie, the bigger the hole), the smaller the range where the focus is good. Thus, for sake of example, let's say the aperture is open at some value X. You might be able to focus on something well between 5 and 7 feet. If you open it wider to some value Y, then the range of good focus is between 5 and 10 feet. This is called depth of field. It's the range where the focus is good. Outside that range, it gets blurry.
George Lucas used this to very interesting effect in the film THX-1138. He had three people at three different distances. He focused on the guy in the back. The front two guys were too blurry to even be noticed. Then, he focused on the center guy. He was in focus, while the other two were out of focus. Finally, he focused on the front guy, and that guy was in focus, while the other two were not. In fact, the effect is so profound, I almost believe he faked it. But who knows.
Controlling apeture is one artistic control you have. In fact, people have used this to great effect, much like Lucas. By opening up the aperture and having a narrow dept of field, you can force people to pay attention to certain parts of the photo (the parts that are most in focus), while the rest of the image is blurry and less in focus.
If you want to see this in great exaggeration, find any good cookbook with huge photographs. Get a Donna Hay cookbook. Not only does she have plenty of photos in the book, the recipes are good too. Each photograph is taken in a way that's become ubiquitous in all of food photography. You take a camera, and shove it mere inches from the subject. This is called macro photography, and you need a macro lens to take photos this close up. Regular lenses won't focus at close range.
When you're that close, with the aperture opened up, you could have, say, a peach, where the front of the peach is in great focus, while the back of the peach is blurred. Food photography uses this all the time, where front parts of the dish are in high focus, but the back parts are very blurry. This creates a dramatic effect, but it's hard to see the dish in full clarity. You
would think that a cookbook would have dishes in sharp focus front to back, so you know what the dish looks like. In this case, artistry trumps practicality.
Apetures have funny numbers. They have numbers like 2, 5, 8.5, and so forth, all the way up to around 22. The bigger the number, the smaller the aperture. I know. It's confusing. I don't even recall what those numbers mean. I believe it's the reciprocal of the number that has something to do with the aperture opening.
The first important innovation in camera technology was automating either the aperture or the shutter, and letting the camer figure out the other part. For example, if you select aperture priority, then the camera computes the how long the shutter should stay open (given the film speed), so you get a correctly exposed photograph. Generally, if you're looking for artistry, you control the aperture, because that controls the depth-of-field, which controls the range of distances where the image is in focus.
However, if you want the camera to be blurry (say, you're photographing a stream of water, and want a dreamy like effect), you might control the shutter speed, and let it stay open longer, while the camera picks the appropriate aperture for you. In general, it's easier for a camera to control shutter speed. For example, if it's very dark, a camera can just let the shutter open for a long, long time. On the other hand, if you pick the shutter speed, the camera can only open the aperture so much. Thus, there may be only certain ranges of permissible shutter speeds and also certain ranges of apertures that are allowed. The rest may not work, if you expect a decent photograph.
Some cameras are even more fully automated, picking both the shutter and aperture for you, so you don't have to think at all. This is for the average photographer who isn't creating art, but merely wants to capture the moment.
Light is a tricky thing to get right. The camera, alas, is not like the human eye, which can perceive a great range of light differences and compensate. It's been said that the eye perceives light on a logarithmic scale. Thus, if something is twice as bright or half as bright, you will only notice it as being somewhat brighter or somewhat darker. This is unlike cameras which notices the differences much more greatly than you do. Also, you have a much greater ability to "focus" your attention on tiny items. You might look at the moon, and it looks huge in the sky. In reality, it's tiny, and when you photograph it, it appears tiny.
There are two other innovations that help out. First, there's the zoom lens. A zoom lens allows you to move closer or further from what you are photographing. Note, this is not the same as moving closer or further from the subject. There's an odd effect that occurs when you move closer to something. They get bigger quicker. Let me explain.
Suppose your friend Justin is standing twenty feet from you. A hundred and fifty feet back is a large building. You start to walk to him and take pictures along the way. Justin will appear larger and larger, while the building behind him will only grow somewhat. It's just a matter of perspective and distance. This relative ratio appears to change, and this is what happens when you physically move closer.
On the other hand, a zoom lens is like taking a picture, drawing a small square at part of the picture, and blowing it up. The relative ratios stay the same. You are just focused on a smaller section that's been blown up larger.
Even so, zoom lenses allow you to get "closer" in to your subject without moving, and people loved zoom lenses for that reason. Occasionally, you see sports photographers with huge, huge lenses. This allows them to get very close-up photos. However, they need very fast shutter speeds as well. When you're zoomed in, any camera shake (it's hard to hold a camera perfectly steady), is also magnified.
The other innovation is flash. Film doesn't do so well in the dark. Even if you leave the shutter open a long time, it's likely to be blurry, and the color isn't so good. Flash sends a bright light to light everything up. However, as you might imagine, the camera needs to know if you are using flash. An automatic camera after all, assumes you are not using flash. All this additional light would normally cause the photograph to be far too white.
Early cameras had some notion of how to compensate for having a flash. You'd hook the flash to the camera, and it would estimate how much light would be flashed, assuming the subject were, say, ten feet away or less. Innovations in cameras allowed sensors to detect the amount of flash through the lens itself, and then close the shutter once enough light was through. This is an amazing marvel, since we're talking about times that are less than 1/20 of a second. The sensors have to work quickly for it to work at all.
Then, in the late eighties and the nineties, the last big innovation of SLR photography was autofocus. For a while, it was up to you to focus. Some cameras had parts of the image that were blurry, and when it was in focus, so was your picture. But, you needed a good eye to focus, and it took a few seconds, even for experienced photographers. Autofocus cameras could do basically as good a job, if not better, in a fraction of the time. Even seasoned photographers began to rely on autofocus, especially in low-light conditions.
Throughout all the innovation, there was one problem. The camera had to be of a certain size. Kodak managed to produce cameras that were smaller than SLRs, but the amount of control and the quality were simply poor. Kodak was never seen as more than a hack, for the casual photographer. No semi-serious photographer would ever use a Kodak camera. The best cameras were Japanese, because they had all the electronics, the lens quality, and they were far more affordable than the German cameras, which were the only serious competition. Nikons, Canons, and Minoltas were perhaps the big three. Among German cameras, there were Leicas and Hasselblads. They were far too expensive for the average photographer, and mostly were remnants of fully manual cameras that used few, if any, electronics.
Originally, I thought it must have been disruptive to camera companies to need all sorts of electronics specialists who could do autofocus, manual and aperture priority cameras. Cameras had mini computers in them, much as automobiles do now. Before that, it was purely mechanical and optical.
But the real innovation occurred when cameras stopped using film altogether. Some Kodak cameras used this weird film, which was basically a circle, with little squares around the edge. Each square was a photo. These were much tinier than normal 35 mm film. Yet, the quality wasn't necessarily better. In fact, you need film to be a certain size just to have decent quality photographs.
Digital cameras don't need film. This means they can be much smaller. And they are tiny. The standard for digital cameras is whether they can fit in an Altoids box. It's almost always Altoids, and not any other product, since anything else is probably stomach medication. The point is, they are now so small that it's easy to carry with you full time. They say the best photographs are the ones you take. Cameras that are physically large are hard to lug with you everywhere.
I used to take photographs maybe two or three times a year, usually around graduation. Now I carry a camera with me everywhere I go. OK, it lacks some of the controls I want, and there are some annoying features in my Canon. but for the most part, it does what it needs to. In fact, my current complaint is everything after the fact.
Think about a regular camera. You take the film out, then drop it off at a place to be developed and printed (developed merely means to prevent the film from going bad due to additional light--it "fixes" the film--it does not mean printed, as most people think it does). A week later you pick it up, and that's that. Put it in a photo album and you're done.
But digital photos? I suppose you could print it up, but you have to get it off your camera onto a computer, so already you need a computer just to store your photos. So, now it's in some sort of directory system, and you need to know some software. If software were written in the old days, it would simply dump out your photos into a directory based on the date of the photos, and then you could view it, and that's that.
But no. Anyone who writes software can't help but change the way it works. Constantly, I know. I work at a software company, and we tweak and tweak and change and change it. We get bored with the way it works and change it again. The way regular film was developed didn't much change for fifty years. The software you use to view your photographs will change next month.
You need a book to use the software. That tells you something about how much work is involved in using software, and why some people wish that software folks would write it once, and forget it. But they can't. They make no money this way, and it's utterly depressing. Like political science students who lament that the average citizen doesn't care to follow politics, the average tech company ought to lament that people won't learn new technology, but tech companies are in la-la land imagining how people use technology in ways they really don't. They are nerds imagining that the world are filled with nerds, and they are wrong.
Anyway, what started as a lesson about film photography has ended as a rant on digital photography software, which no one can decide a uniform easy way to manage.
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