More and more lately i've come across people that while they seem to like taking pictures, have no clue about some of the most basic ideas behind photography, and are amazed at some of the simplest techniques used with their cameras to achieve results they never thought they can have.
This is all partly due to the oversimplification of the camera, as the designers make cameras simpler and simpler to use, a lot of people rely on the safety of the "Auto" setting to take every picture, basically bypassing the art of photography and taking (most of the time, those typical, white out, hard shadows, red eye, dark, blurry pictures) we see in nearly every family album. The thing is, you really don't have to be a professional photographer to take great shots, all you need is to gain a little understanding of the concepts, get to know your camera, per say, and move off the auto setting, to take, fewer, but better quality shots, more interesting shots, and achieve effects that you thought were only possible to do with Photoshop, or only a professional photographer can take...
So, let's get to know your camera a little bit. There are many digital cameras out there, they range in price from 30 to 60000 dollars, and ranging in sizes from cameras built into phones, to cameras that take 2 hands and a tripod to operate. From under 1 to over 60 megapixel, from built in tiny lens and digital zoom to DSLRs. Let's define the range of cameras i am going to discuss here, I am talking about cameras that generally have a little optical zoom (thus they generally have a little slide out lens), usually starting with the size of about a deck of cards, ones that generally have a little wheel on top or back that allow you to select modes of operation and ofcourse this is applicable to DSLRs as this is really a stripped down basics of mostly any digital camera.
Pixels:
Ok, so let's first discuss the megapixels, what they are, and how they should effect your choice of a camera. I find that a lot of people, when talking about cameras, range how good those cameras are merely by how many megapixels it has (really an incorrect use of that term, but we'll get to that). So what is a megapixel? Well first we drop the metric prefix mega, and strip the word to "pixel", a pixel is the smallest item of information of an image, it is a dot, a colored dot that makes up the image. I say the smallest item of information because you can not "split" a pixel to get more information, contrary to what you may see on CSI... So a lot of those different colored pixels in a square array make up a picture. Your screen, if it's set to 1280x1024 shows you a mesh 1280 pixels wide by 1024 pixels high, the total amount of pixels on that screen is 1,310,720 divided by 1024 its 1280 kilopixels or 1.25 megapixels. Megapixels indicate the level of detail your digital camera sensor can capture. A digital camera sensor is a special device that is comprized of cells, each cell, when hit with light (photons), produces a tiny electric current, that is read and interpreted by the camera's processor into a color value. Thus each cell corresponds to a pixel on the screen.
So then what is the difference between a 5 and a 7 megapixel camera? The size of the final image, a 5 megapixel camera can take a picture in 2584x1936 where a 7 megapixel camera takes a picture in 3056x2288. Big difference? Not really, consider how you are going to view this picture... say you print both pictures, what would the size of pictures have to be for one to start noticing the grain? This is different when printing with different purposes in mind. For example printing at 300 dpi, you get an ultra high resolution photo that shows no pixelation at even the closest distance of about 8.6" x 6.5", normal photo print is around 100-150 dpi, at arms length a photography professor wont be able to tell the difference between a 150 and 300 dpi print, plus most people tend to view larger prints from longer distances, so printing at 300 as a home photo is rarely needed (though that already produces a fair-size photo), at 150 dpi you can print photos 17.2"x12.9", which is a fair sized print for any wall, or at 100 dpi 25.8" x 19.4" poster can be produced, similarly a 7mp camera will produce a normal 150 dpi picture of 20.4"x15.3", not a hell of a big difference, considering that nobody would be able to tell the difference between the 150 dpi 20.4"x15.3"@7mp and 100 dpi 25.8"x19.4"@5mp posters.
So what is the conclusion here? You dont need the top notch cameras to get nice-sized prints, most people for their home will rarely if ever need to exceede 5mp. More is not a mean to say better here, a person who knows a little about their 5mp and can come up with creative shots will have a better family album then a person who uses his 7mp as a point and shoot on full auto all the time...
Zoom:
What is the difference between optical and digital zoom, and is my camera better if it can do 16x digital zoom then a camera that can do only 4x digital, but also 4x optical?
What is optical zoom? Optical zoom is the zoom that can be provided by moving lens pieces, simplest way to think about is this, take a magnifying glass and put it really close to the subject, you dont see a lot of magnification, now move your lens away from the subject, which effectively magnifies that subject through the glass. Like the magnifying glass, all lenses have limist to magnification, and every time you magnify (or zoom) you do two things, you narrow your field of view, and you also decrease the amount of light that is hitting the sensor, and where you can't see this too much on a sunny day, in the darker conditions, your exposure (which i will discuss in a bit) will, however differ.
What is digital zoom? Digital zoom is an excuse of the camera makers for not creating proper optics, so to give you an illusion of zoom, they crop the data off the sensor, and decrease your final resolution. Yes it is THAT cheap of an idea, and hence why no DSLR that i know of has that so-called functionality. In all reality, the difference between taking a shot at 0 zoom and at 4x zoom is the same as if you took that shot in 0x and cropped it to the size of the 4x zoom photo you just took.
So what zoom do you want to use? Optical... If you cant get a good shot with that, get closer to the subject. If that is not a possibility, still refrain from using digital zoom, just take it at maximum optical and then crop to your liking, you get more data and thus more photo to play with to crop it differently for whatever need you may have...
How should optical zoom effect your choice of a camera? Simple, its like selecting what lens you will use most of the time on your SLR. On a standard camera, 35mm zoom is about what a human eye sees, all the X(times) zooms are a derivative of that, 2x zoom means that you are shooting at 70mm zoom on an slr, divide by 1.5 to get the value for DSLR. So a 4x optical zoom on a standard digital camera equates to a 35-140mm lens, or about a 24-90mm DSLR lens which, quite honestly will cover most of the range of shots that i would take. I have a 14-70 lens i use all the time, and there have only been very, very few occasions when i wanted more/less. So 4x optical zoom is about ideal for most people's uses.
So what actually matters:
What actually matters on the camera are things that most people don't look into. The sensitivity of the sensor, the color reproduction, the grip on the camera and the position of the controls and most of all, the ability to manually adjust the most settings that you can possibly get away with. Ideally you want that wheel to have a M (manual) setting.
Another thing to look at, perhaps, if you are thinking about getting more into getting great shots, if your camera has a standard hotshoe adapter for flashes and flash syncing. This depends on what it is you want to do, but you can have your own home microstudio with an off camera flash system for as little as about a thousand dollars.
For someone getting into more advanced photography, but only very recreationally, looking for a point and shoot, i would recommend the Cannon Powershot G series, you can pick up a G10 for under 500 bucks, and it has nearly everything an advanced home shooter is going to want, from full manual control to a hotshoe, raw mode, iso up to 1600, actually 3200 in a special shooting mode, 5x wide angle optical zoom, image stabilization, this is basically all and more then most people need, but that would be my point and shoot camera of choice...
Never the less, lets discuss some digital photography terms, this applies to most cameras, even some of the cheapest cameras, i have been able to find ways to adjust some of these, so while maybe you cant adjust all the settings and thus terms we'll discuss here, some is still better then none.
Terms:
4 of the mainest terms in photography:
Apperture:
Apperture is an adjustable opening through which the light passes to the lens. You open and close the apperture to set it to settings anywhere between 1.4 or less to 22 (22 is usually the highest). Contrary to standard logic, the smaller the number, the wider the apperture is open. Each stop decreases exactly half the light of the previous stop. This controls the amount of light hitting the sensor, this also controls the depth of field you will get. This is the F-value or F-number also referred to "F-stop" or just "stop". Standard values are 1.4 2 2.8 4 5.6 8 11 16 22, these are powers of
This is how photographers measure light actually, in stops, and generally, photographers not married to a light meter will measure light relatively to ambient (which is light that is already there), but i will explain that concept in a separate section, for now, apperture is the amount of light that the lens passes through to the sensor
ISO:
ISO, in the traditional sense is how sensitive your film is to light. ISO can range from 50 or less to over 6400, the higher the value, the more sensitive to light the film was. Similarly with digital cameras the sensor will be more or less sensitive to light that it's presented at different ISOs (rather ISO equivalents). Unlike on a film camera you can change your iso for every picture you take, which is an advantage, but beware, higher sensitivity to light does not come free. The higher ISO's will allow you to take pictures at decent shutter speeds (i will discuss in the next section) in low light conditions, the trade-off is something called ISO noise, the higher your iso, the more prone to getting noise (grain, its noticeable). Unlike most old school photographers i dont believe in choosing the lowest ISO all the time, i think that ISO, like all other settings, is something that one should adjust for the situation, i will discuss this in the ballancing section and in techniques.
Shutter Speed:
Shutter speed is the last of the three major parts to any photo, shutter speed is the length of time in which the sensor is exposed to light. It varies from 1/8000's of a second or less to hours. Something to remember here, physical shutters generally stop at about 1/600's of a second, because of the physical restrictions (shutter is 2 plates that slide across, one opens up the openning allowing the light to fall in, the second closes the openning, thus preventing the light from coming in and also evenly exposing the sensor. The super high shutter speeds are acieved by opening the physical shutter and cutting the power of the digital sensor at some point. Most point and shoots will not have this, so you are basically confined to shutter speeds of down to 1/600 of a sec (and that is fast).
Exposure:
Combine the three of the above terms and you have exposure, the total amount of light that is allowed to fall on the photosensitive material. It is a combination of all of the above factors combined. Note, there is no "right" or "wrong" exposure, every situation you will have a different exposure, no such thing as too dark, or too light, shots can get more meaning by bleaching out the background, others can look totally awesome by only showing a part of the whole picture that was well-lit; this is something that you as photographers will get to define.
There are more terms in photography, composition, selection, lighting terms, etc, but these 4 are your most foundation pieces, knowing them, knowing how they relate to one another, and nowing what changing one will do to your final product is what involved photography, something i want those who have read this far, is all about in its core.
Another term before we get finished with this section.
White balance:
This refers to what your camera, or your photo, defines to be the white color. Your eye sees a lot of light as white, light coming from a tungsten light bulb, and daylight bulb, light in the shadow and out in the open sun-lit areas, to be of a similar color. But the camera sees those lights as different colors, thus to achieve the colors you are looking for may be a matter of adjusting the white balance. The adjustment changes the intensities of the color values of red, green and blue, and this influences everything in the picture, all the neutral colors to be perceived as they were, or perhaps as they were not (depending on what it is that you want to do). White ballance refers to adjusting color temperature, as different things produce different temperature light, it is also crucial to know which way and when to adjust your settings, though for what its worth, you can color correct in post processing... Temperature, at which the heated black-body radiator matches the color of the light source is that source's color temperature. All that means that when i say that the temperature of an incandescent tungsten-fillament light bulb is around 2700-3300K that means that if i was shooting a white sheet of paper lit by an incandescent light bulb, it would appear to be yellow/orange if i shot it at say a daylight white ballance (around 5000-5500K) the higher the temperature, the more from red to blue you are going to push. (I will discuss this in one of the techniques, whenever i get to those.
Controlling your light:
So now that you know what all the settings that your camera that control things are, how do you use them to control your picture?
First of all let's discuss ambient light, it is the light that is available in the environment. There will be different amounts of it depending on what and when you shoot, but you will nearly always have some ambient. When you take a shot on auto, your camera will attempt to interpret the amount and temperature of light, adjust its settings and take a picture that mathematically works out to have good average lighting over the picture. This is a good start for your shots, but use this as a sort of a light-measuring device. Some studio photographers are married to their light meters, but field guys will generally take some shots on auto, figure out their ambient exposure, and play off of that.
So how do we control light from the ambient?
One thing to remember here, shutter speeds and appertures have been fairly standardized, in such a way that dropping a stop of light (meaning raising your F-Stop by one value say from 11 to 16) and decreasing your shutter speed by one value (say from 1/80th to 1/60th) will produce the same overall exposure. Changing the sensitivity of the sensor (ISO) will allow you to change one of these values without affecting the other, and this may come in handy depending on what it is you are trying to do.
So now what does changing Apperture or shutter speed in relation to one another acoomplish?
The apperture controls the amount of light that hits the sensor, also it controls the focal length of the shot. Focal length is the depth of field that will appear to be in focus on the picture. Sometimes you want that to be very big, thus you will set your apperture to be higher, 22 will have mostly everything in focus from the foreground to the back. But that is not always the desired effect, sometimes you may want to blur the background to make the subject stand out. Consider taking pictures of your friends at a party, setting a really short focal length may produce a photo where only the subjects are in focus drawing attention to them in the picture. Alternatively when taking a group shot, you might want to have your apperture more closed (higher number) to make sure everyone is really in focus.
Shutter speed controls the freezing of your subject in motion. Above you can easily freeze a runner in motion at 1/100th or 1/300dth of a second. Keep in mind that in order to achieve the right exposure this may mean dropping the field of depth to get the right exposure.
With shutter speeds slower then 1/60th i would recommend to consider a tripod, as even hand shake will be visible as blur, but i will say that having a decent steady hand, and bracing against things, you can achieve good consistent results up to a 1/40th, this will just take some practice.
Its all this playing around that makes things in photos really pop out, you can freeze a flying bug, you can capture the motion of the water, you can paint your name in the dark and capture the spin of the earth. Understanding these and most of all playing with settings and knowing what you will achieve with changes is what photography is all about. You may spend days playing with things, and more time prepping up the shoot, but the result you get can truly awe your family and friends...
I will stop this part here. You will grasp the concepts above with techniques. Techniques are like tools in your photo arsenal. Every situation may require a different technique, one that you may know and have already used, or one that may have not, or you may have to come up with your own technique to achieve the results you want, bottom line, techniques are something you always have with you in your head, it is often another way to make a shot interesting or achieve an effect you desire. I will post those in separate posts as this is already getting to be very long, and my hands are getting cramped from typing. I hope you enjoy your intro, post if you are interested in learning some techique behind an effect you have seen somewhere (link to a photo would be nice) , if you have questions, or just interested in reading more.
Sources:
Wikipedia
Strobist
Digital Photography School
