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Photography 101
Introduction
Since the introduction of the 35mm camera, photography has been one of America’s most loved activities. It’s so incorporated into our daily lives, that most people wouldn’t even list it as a hobby, yet they own at least one camera and take pictures as part of their daily life. The accessibility of the digital camera has increased the popularity of photography exponentially. Once the initial investment in a digital camera has been made, there are generally no additional costs such as film and processing to make one think twice before taking a picture. Cameras are also smaller than they used to be, and much cheaper. All these factors contribute to photography’s current popularity. Unfortunately, as cameras became more and more accessible, photographers generally failed to become more and more educated on the subject of photography. The misconceptions and general lack of knowledge surrounding the art of photography has grown proportionally with the pastime itself. This article addresses that issue. It will include enough of the basics to help you get started down the road of photographic improvement. Some of the content will be aimed at those who are only interested in using a camera as a tool to convey information. So, if all you want to do is take a bud shot without having technical issues stand in your way, then read on, because there’s plenty of useful information here. On the other hand, some of the content is aimed at people who desire to expand their knowledge of photography, or wish to take it to the next level. Hey B., Why Should We Listen to You?! The simple answer is that you certainly don’t have to. However, there are many folks around here who seem to enjoy learning and expanding their minds, so for those of you who fall into that category, I hope you find this article helpful. In the world of photography, it’s your portfolio, not your credentials, that gets you future jobs. However, I don’t plan on revealing my identity, so unfortunately posting my website’s address is out of the questions, and credentials will have to do. I have a BA in photojournalism from one of the best photo schools in the US. I have a background in photojournalism. I currently make a very good living as a wedding and portrait photographer who owns his own business. I charge a day rate upwards of $4,000, and every year I have more folks who want to hire me than I’m willing to work for. I have a vast knowledge of lighting, post-production and general photography skills. This isn’t meant to impress you. I simply want to convey the fact that I know what I’m talking about! Photography is my life, and it supplies me with all I need, including a place to grow. 1. Camera Gear & Equipment I’m going to get this topic out of the way first for a few reasons reasons. First, even though it’s one of the least important aspects of photography, it’s one of the most common questions I’m asked. Two, it will provide an effective way for me to differentiate between the two different types of photographers out there, and how they each use photography to meet their goals. Last, although owning expensive equipment will never make you a good photographer or enable you to make good images, it is necessary to have equipment that’s adequate to meet your goals. By adequate, I mean you need to have equipment that will allow you to transfer the image you envision in your mind onto film or a computer in an accurate manner. Picture Takers There are two kind of people who use cameras. Although there is no clear line that separates these two groups, most people tend to fall in line closer to the first group. This first group is the Picture Takers. This is the group that went through a growth spurt when the first compact 35mm cameras became available, and grew even larger when compact “point & shoot” digital cameras became inexpensive enough to become a household item. For most Picture Takers, the process of taking a pictures involves finding a subject that you personally want to photograph, pulling out an automatic camera, pointing it at the subject and snapping the shutter button. Generally, Picture Takers:
This image is an acceptable snapshot, but it has no sense of style or design. Almost all the decisions were left to the camera's automatic functions, and what little control the photographer had wasn't taken advantage of. If this category describes you, then you need a point and shoot camera. Anything else will be more of a burden than an enabler. If you don’t believe me, then read the section of this article on SLR cameras. The cost, the bulk and the knowledge needed to use them is incredible. Professional cameras don’t make professional images. Knowledgeable photographers make professional images. It’s very important to understand that, because there’s lots of disadvantages to getting more camera than you need. Don’t go buying an expensive SLR camera because you think it will help you win the Photo of the Month contest. . .it won’t! Don’t get me wrong, just because your needs are simple doesn’t mean all cameras are alike. Picking the right one will take only a short time, and it’s important to make the right choice. The first thing you need to do is forget everything you think you know about choosing an automatic point & shoot camera. Most people have it all wrong and end up with a total piece of shit, when they could have gotten a better camera that meets their needs for the same price. Here’s what I recommend getting for all you Picture Takers out there:
Image Makers The second group of photographers is the people who are the Image Makers. This group is a very small percentage of camera owners. Many of the people in this group make their living in the world of photography, or are very involved as an amateur. For Image Makers, the process of making an image involves finding a subject that is interesting to both you and your desired audience, thinking of desirable ways to capture and portray your subject, thinking of the technical aspects that will be necessary to follow through with your plan, and then finally making the image. Generally, Image Makers:
This image was shot by a photographer who made quite a few intentional decisions during the photographic process. The SLR camera was shot in manual mode, and the photographer made good use of light, composition, a storytelling moment and manual exposure. If the above characteristics describe you, then you’re probably a good candidate for a SLR camera. SLR stands for Single Lens Reflex camera. Although there’s a number of disadvantages, they are designed to be manually manipulated by the user, which allows the photographer to have control over everything they need to translate the mental image in their head into a image others can see. In order to reap any of the benefits they offer, they must be shot in manual mode. By manual mode, I mean that the photographer is manipulating the aperture, the shutter speed and the ISO. Digital SLR’s have some serious drawbacks, and as mentioned earlier you won’t reap any benefits from an SLR unless you know how to shoot manually, so be sure that you’re ready to commit to the learning process before buying one in hopes of improving your images. Here’s what I recommend for all you Image Makers out there:
Hopefully by now, you know whether you’re a Picture Taker or an Image Maker. If you still don’t know, assume you’re a Picture Taker, and learn what you can. You can always work and learn more from there if you choose. 2. Subject & Context: Choosing a Subject & Location This is important, and it applies to both Picture Takers and Image Makers. Photography is the art of exclusion. A painter adds desirable elements to their painting, but a photographer must choose their subject and then work to exclude elements of the background or surroundings (or even part of the subject) that are seen as undesirable. Often, a large part of what separates a snapshot of a ___________, from a killer shot of a ___________ is the particular subject that’s chosen. You could fill those blanks in with any object you wanted, but I’ll use a top cola as an example. Many photographers, Picture Takers especially, will walk into their grow area and snap a shot of the cola that’s right in front of them and easily accessible. This is a prime example of picture taking (as opposed to image making). Just pull out a camera and snap a picture. Wrong! Take the time to find the best cola in the room. Now, determine which side of that particular top cola is the dankest. Yeah, it might take a few minutes to dig to the back of your ebb & flow tray to do these things, but it’s making these types of efforts that begins to turn your average joe into a true photographer. The more interesting your subject is, the wider your audience will be. Period. Find the best subject possible. In addition to choosing a great subject, choosing your location wisely. By choosing a great location, you dictate what the setting will be. Choose a place that will show the subject the way you want it to be shown. If your subject is a single plant and you want to show the plant structure, then move it in front of a brightly-lit white wall so the green plant starkly contrasts against the white wall. If you’re shooting the same plant but want to show it in it’s natural surroundings, then bring it outside and find an interesting backdrop for it, such as a big blue sky and maybe include the sun. Only you can decide what location is best, but it should be relevant and intentional. Your subject should be the center of attention, and everything other element in your frame should give it context or be included for another specific reason. Much of a professional photographer’s time is spent dealing with these very issues. Think of a wedding photographer. Out of everyone at the wedding, the pro will usually have the best shots. They’re also the only person at the wedding constantly moving around for better angles, choosing their backgrounds, asking the bride to step into some better light while having her makeup done, etc. If you limit yourself to the easily-accessible subjects, and whatever location is easiest, you’re also limiting the potential of your images. This is a picture that could be described as 6 foot 6. It was taken from about 6 feet away and about 6 feet off the ground. This typically indicates that the photographer didn't choose a specific subject, didn't think about the background, and/or didn't think about anything other than snapping the shutter. If you wanted to send some images of this garden to a friend, would they be interested in this picture? Should they be interested based on how much effort the photographer put into it? This is an image of a single flower from the same garden pictured above. A specific flower was chosen, a specific angle was chosen to shoot from, and the image is much better because of it. Would this image make someone more interested in your garden than the 6 foot 6 picture above? 3. Composition Picture Takers and Image Makers both make a decision related to composition before each picture is taken. They might not be aware of what their decision is, but the edges of the frame need to fall somewhere. Think of composition as fine-tuning your location & background. Composition is the creative decision that’s made when you frame your shot. Your composition should support your subject, and is one of the powerful tools a photographer has when trying to show an image in an interesting or dynamic way. It’s very much tied in with your location. The better your location is, the more interesting compositions it will provide. There are some general rules to remember when composing your shots. You can and should experiment, but these are some general guidelines and prevailing norms: This image makes use of repetitive shapes and leading lines. The subject is the person reading the paper, and everything about the composition supports the subject. The shapes provide an interesting way of showing the context of the subject, and the lines lead diagonally to her. This image makes use of the Rule of Thirds. Imagine your camera's viewfinder or LCD screen split vertically and horizontally into thirds. As a general rule, place your subject where two of those lines meet. This image has the subject placed in the lower right third of the frame. If your images aren't turning out the way you would like, a great place to start improving is by getting closer to your subject. Fill up your frame with the subject! If you don't fill it up, have a good reason why, such as including context or background for a specific reason. Get low and show your subject from an interesting perspective. This image includes the grass as a border for the lower part of the image, which also makes the flower look very tall. Get high up and show your subject from that view. Often many different perspectives will work for any given subject. As the photographer, it's part of your job to match the subject with an appropriate composition. Hide undesirable parts of the frame by re-composing if you need to. Here, a small leaf is in focus in the foreground, and there's a piece of garbage in the garden. By re-composing the shot, both elements are eliminated. Photography is the art of elimination |
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4. Perspective: Why Focal Length Matters
Consciously choosing a focal length is something that almost all photographers are bad about, regardless of whether they’re a Picture Taker or an Image Maker. Picture Takers believe that the zoom on their point & shoot camera is simply a convenient feature that allows them to shoot subjects that are both far away or close to them. They don’t understand they relationship between the zoom button on their camera and the perspective the resulting image will have. Image Makers who aren’t conscience about their choice of focal lengths generally don’t own enough lenses. If you only buy one lens, you’ll only have one choice when choosing focal lengths! If you’re going to commit to buying an SLR camera, make sure you have a reasonable array of lenses to go with it! Your focal length, along with your composition is what dictates your perspective on a subject. Your focal length will also affect your depth of field and exposure settings. It should be chosen purposefully and has a great impact on your final image. Wide-Angle Focal Lengths With a point and shoot camera, you shoot wide by zooming all the way out. With an SLR camera, I’d consider a focal length of 35mm to be the longest focal length that could still be considered a true wide-angle lens. A 14mm lens is about as wide of a lens that is still useful for a wide array of subjects. 16-35mm zooms are very useful when there’s an abundance of ambient light. Assuming all three shots are framed in the same way, a wide lenses would require you to be closer to your subject than a standard or telephoto lens would. When shooting in a cramped location, sometimes a wide angle lens will be your only choice for anything but the smallest details. Wide-angle lenses have short focal lengths, and will distort a subject that is close to the lens. This distorted effect can be used to your advantage, or it can detract from an image and be distracting. A freshly caught fish can be distorted to look bigger when held out at arm’s length towards a wide-angle lens. A cola can look monstrous when photographed from a wide perspective. This is an image of discarded clothing near the US/Mexico border. To emphasize the significance of the clothing in relation to the fence, the clothing was distorted to look as large as the fence. Sometimes distortion is bad. Look at the size of that forehead! Don’t shoot a head shot with a wide-angle lens, because the parts of the subject’s face that are closer to the lens will become distorted and they will look awful. Wide lenses are at their best when shooting large objects, showing landscapes, taking group portraits, purposefully distorting an object and/or including the background as context for your subject. When handholding a camera, the slowest shutter speed that can be used without visible camera shake is 1/focal length. For example, assuming you can hold a camera as steady as the average photographer, a 200mm telephoto lens can be shot at roughly 1/200 of a second before camera shake starts to blur your image, but a 16mm wide-angle lens can be shot at roughly 1/15 of a second. A result of this rule is that in low light situations without flash, shooting wide is generally your best bet, as the shutter can be dragged much longer than with other kinds of lenses. A fast moving subject might still require a faster shutter speed, but camera shake won’t be a problem if the above rule is followed. This image was shot with a 16mm lens @ 1/15 of a second. Wide angle lenses are great for adding camera blur because they allow you to work close to your subject. The closer a subject is to the camera, the slower it can be moving and still add blur to the image. The farther a subject is away from the camera, the faster it needs to be moving for there to be blur in the image. Drag the shutter and let the subject move through the frame to create blur. Experiment with different shutter speeds to get the amount of blur you want. Notice that with the same slow shutter speeds, a nice panning shot can be captured by simply following the subject as it travels through the frame. All else being equal, a wide lens will give you the greatest depth of field. The shorter the focal length, the more depth of field you can and will get. This allows you to layer your images and show interaction between subjects very well. Even when very wide apertures are used, depth of field can be very great. Notice how the objects close to the camera are in focus, as well as the objects in the far distance. Wide angle lenses are very poor tools to choose when trying to create a out of focus background. Normal Focal Lengths Normal lenses have a focal length somewhere in the 50mm range, and they see things similar to how the human eye sees them. A point and shoot camera can shoot with a normal focal length by zooming all the way wide, and then zooming back in a little bit. SLR users can choose either a prime 50mm lens, or a zoom lens in the range of 24mm-70mm will cover all your wide to normal focal length needs. I recommend the 50mm prime, but if convenience is an issue AND you’ll be shooting under bright conditions, then a zoom may be fine. A normal focal length provides a good all-around perspective that’s great to keep on a camera when you don’t know what kind of subjects will present themselves. Normal lenses are great portrait lenses. Distortion isn’t a problem, so you can shoot anything from a head to toe portrait to a tight headshot and not have to worry about distorting your subject. Normal lenses give the photographer the greatest latitude when it comes to depth of field. It’s very hard to get a narrow depth of field with a wide-angle lens, and it’s very difficult to achieve great depth of field with a telephoto lens, but a normal lens can do a little of everything. In the three images posted above, notice how the edge of the woods slowly goes out of focus as the size of the aperture is increased. Most point and shoot cameras have a very narrow range of available aperture, with that same range becoming smaller as you zoom in to longer focal lengths. SLR users have a much wider spectrum of apertures to choose from, especially with professional lenses. If you use a large aperture and/or a telephoto lens, you can draw attention to the subject by placing it in a very narrow focal plane. A telephoto lens does this best, but a normal lens will do it quite well also. A point and shoot camera will do this, but not as well as an manual SLR camera. With a medium aperture, a photographer can draw attention to the subject without completely blurring out the background. This can make the subject pop out of the background, but still give it context. Most images taken with point and shoot cameras fall into this category. With a small aperture and/or a wide-angle lens, the focal plane will be very deep, and much of the subject’s surroundings will be in focus. Although a wide-angle lens does this the best, a normal lens can achieve great depth of field as well. This is my spare shower stall, filled with LA Confidential. The good stuff! Telephoto Focal Lengths A telephoto lens is any lens of a longer than normal focal length. For example, SLR users would call a 85mm, 135mm or a 200mm lens a telephoto lens. Point and shoot owners can zoom their cameras in a good amount to use a telephoto focal length. The most obvious advantage of a telephoto focal length is that it gives photographers the ability to work a good distance away from their subject. However there are also other consequences of using a telephoto lens. Telephoto focal lengths tend to have very shallow depth of field. They are very good at isolating a subject through selective focus. Even using a small aperture will only yield a relatively shallow depth of field. If great depth of field is required, choose a normal or wide focal length. Telephoto lenses tend to give the different layers of an image a compressed look. Scenes look more flat flat and one dimensional. This is the exact opposite of the layering effect that happens with wide angle lenses. This hiker looks to be standing against a studio backdrop, but the cliff face is actually over a mile away. Telephotos focal lengths allow the photographer to get detail shots while maintaining a comfortable working distance from the subject. Try to fill your camera frame with a small subject using a wide angle lens, and not only will the object look distorted, but you’ll need to be only inches away to frame it properly. This can be uncomfortable for the photographer, but also some subjects may become uncomfortable. More to come. . . |
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8 members found this post helpful. |
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Hey B, that's a great post..and I hope the other photographers here might have something to say also..
It's always great to compare results and show off the good stuff.
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#4 |
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I hope people enjoy it and take the time to read it. The rest will be posted soon. Thanks for stopping by and takin' a look!
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Senior Member
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Wow, thanks for taking the time to post all of this...Extremely informative and appreciated.
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Below is a link to all of my grow reviews...there are a bunch so get off the clones, dive in, and find some new genetics to appreciate! Click here for a link to all of my grows
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#6 |
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Member
Join Date: Aug 2008
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![]() ![]() thank you thank you thank you!This is not only a great tutorial post, it's an extraordinary gift!
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Join Date: Apr 2009
Location: South Denver Area
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excellent post. i'm in
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Senior Member
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Hey B thanks for sharing here in the photo forum. The time you took to assemble and post this amount of your personal information shows your love for the art. A valuable reasorce for our members indeed..Thank You..DD
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Please join me in my Summer 2018 All Black Grow
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#9 |
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I'm glad folks are enjoying it! I've got another section to post in a few minutes. Thanks for stopping by everyone!
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5. Exposure: It’s All About the Equivalents
The exposure is what determines how much light reaches the film or sensor. The combined value of the ISO, aperture and shutter speed settings is what determines the exposure value. There’s almost always dozens of values for each variable that will make an acceptable total value. These are called “equivalent exposures.” To see an example of this, look at the (3) purple flower images in section 4 of this article. Each was made with different ISO, aperture and shutter speed settings, yet each image’s overall exposure (brightness) is the same. This is one area that differs greatly between Picture Takers and Image Makers. Picture Takers give up not only the ability to choose the overall exposure, but also which equivalent is used, because an automatic camera picks all this for you. For the Image Makers out there, exposure is a creative decision. For example, sunsets can be underexposed to get deeper color saturation, and fair complexions can be overexposed to smooth out the appearance of skin blemishes. However, for the sake of learning, we’ll call an image “correctly” exposed when it looks somewhat as did in real life. We’ll cover how to determine your overall exposure a little later, in the practical application section. For now, just concentrate on learning the ins & outs of exposure in general. Here’s the catch when it comes to exposure: the potential tonal range that your camera is able to capture is much narrower than the tonal range our eyes can see. Your eyes see the brightest spots in a scene the same way they see the darkest spots in the very same scene. Your camera is much more sensitive than that, and can only show a narrow range of tones. This means that shadows will be much darker, and highlights will be much whiter and more blown out. To combat this effect, set your exposure for the part of the image that you most need to be properly exposed, and the rest falls where it may. This image of my outdoor garden was exposed for the subject, which is the small plant. The shadow created by my shoe in the lower right corner appears much darker than it did in person. On the other end of the tonal spectrum, the white rocks in the background look much brighter than they did in person. Don’t see this characteristic as limiting. Instead, see it as a way to make your subject stand out from the other elements in the image. In this case, the blown out rocks behind the subject really make the dark green plant “pop” out of the background. If an image is overexposed, it’s subject too bright. Overexposed is also called “blown out.” All of these terms refer to an exposure setting that allowed the detail in the highlights to be lost forever. Detail is lost whenever a part of the image goes completely white. That information can’t ever be recovered, even in Photoshop, so be careful when overexposing. This is a fridge I used to grow in. The subject (a small Grape Ape plant) is overexposed, especially near the top of the plant, and the white 2’x2’ ebb & flow tray is completely blown out. This blown out area can never be recovered. If an image is underexposed, it’s too dark. Underexposure allows the shadows of an image to go completely black. When an image has areas that have gone completely black, the detail in those areas is lost forever. As with overexposure, what is lost can’t ever be brought back! Although our Grape Ape plant didn’t completely lose any detail when it was underexposed it by 2 stops, it certainly is too dark to see its details well. Notice that the tray is still blown out from overexposure. If the tray would have been our subject, this image would be called overexposed, not underexposed. In this image, the highlights and shadows on the Grape Ape plant both fall within an acceptable range, so we’ll call this image correctly exposed. The tray is still blown out, but again, we don’t mind as long as it isn’t distracting and the subject is exposed properly. In this case, it makes telltale sign of the dark green cannabis leaf stand out from the white background. Exposure is something that Picture Takers don’t have to worry about too much. Their point & shoot camera will decide on an overall exposure and an equivalent for them. This is why those cheesy little icon dials on most point and shoot cameras is so ridiculous. The manufacturer states that “Sports mode” is different than “Night Portrait Mode,” which is different than “Portrait Mode.” But in all reality, every setting does the same thing. The camera picks an exposure, then assigns an appropriate combination of aperture, ISO and shutter speed. There’s really no creative advantage given to a photographer who’s diligent about constantly setting their icon wheel appropriately. The camera is still doing all the work, and the photographer has no creative control over which equivalent exposure is chosen. If you’re an Image Maker armed with a manually controlled SLR camera, exposure can be very daunting at first. You can take control of your images’ exposures by learning to manipulate your ISO, aperture and shutter speed. ISO is the easiest one. You set it to the lowest value you can, then leave it alone. But aperture and shutter speed will be a little trickier to master at first, because they’ll have a huge impact on how your image look, yet need to be manipulated together shot to shot. ISO The ISO is the speed of the film or camera sensor. Common ratings are ISO 100, ISO 200, ISO 400, ISO 800 and ISO 1600. A higher ISO means the film or sensor will be more sensitive to light, but also produce more graininess & noise. For example, ISO 400 needs half the light that ISO 200 does to make the same exposure, and it needs 1/4 the light that ISO 100 needs. The problem is that ISO 400 is also twice as grainy as ISO 200, and four times as grainy as ISO 100. Low ISO’s are good. The lower the better. It should only get bumped to a higher value when the current setting isn’t sensitive enough for the ambient lighting conditions. Generally speaking, outdoor photography during daylight will be ISO 100 or ISO 200. Indoor shooting generally calls for ISO 400 or higher. The ISO is usually set to the lowest possible value that the ambient light allows, and only bumped up when drastic changes in lighting occur. The majority of the shot to shot exposure changes deal with aperture and shutter speeds. This is a good thing, because it simplifies the whole process of equivalent exposures for you. This image was shot at ISO 200. It has no graininess to speak of, but you generally need a lot of light and/or wide apertures to pull it off. Almost all cameras will have no grain at ISO 200 and below. This image was shot at ISO 400. There’s not too much grain in there, but it’s noticeable. Images such as this example could still be printed in color or black and white. Either look would yield a great print. This is the (practical) upper ISO limit on many inexpensive cameras. Lots ‘O Grain! It sounds like a cereal, but it’s really enough grain to ruin a good image. Many times these images are presented in black and white, where graininess tends to be more acceptable, and even can be credited with contributing to certain sought-after looks. Generally though, grain can always be added later, so use the lowest setting possible. One of the biggest advantages of professional cameras over point & shoots or prosumer SLR’s is the ability to shoot at high ISO’s. I use a Canon 1d MkII pro camera body, and when shooting weddings, I can safely shoot at ISO 1000. The newer Canon 5D MkII can shoot as high as ISO 3200 and still look better than my camera at ISO 1000. What does this man to Joe Photographer out there? It simply means that better cameras can shoot under darker conditions. It can be quite a big advantage in certain settings! Aperture The aperture is the hole in the camera’s lens that determines how much light enters the camera body when making an exposure. A side effect of the aperture setting is depth of field, which has already been covered. The aperture is expressed in “f-stops,” or simply ”stops.” Common settings are f/2.8, f/4, f/5.6, f/8, f/11, f/16 and f/22. Learning to set your aperture isn’t as easy as setting your ISO. ISO is set to the lowest number possible and then left alone, but the aperture might very well change from shot to shot. Shutter Speed If the aperture determines how big the hole in the lens is and dictates depth of field, the shutter speed determines how long the film or sensor is exposed to the light and dictates whether a subject will be a blur or a sharply-frozen statue. It’s expressed as a fraction of a second. For example, 1/200 is twice as long as 1/400. When handholding a camera, your shutter speed needs to be at least 1/focal length, so when shooting with a 100mm lens, you should use a shutter speed of at least 1/100. For a 135mm lens, the closest shutter speed is 1/125, so that’s the slowest you should use with that lens. The shutter speed that was chosen for this baseball image was 1/2500. As you can see, it was fast enough to freeze the player’s movement, but not quite fast enough to freeze the ball. This isn’t good or bad, it’s simply a creative decision the photographer made. When combined together, the circled values create one correct exposure for a particular image. If we make a change to one value, one of both of the other variables needs to be changed to compensate. In the same example, if we open up our aperture from f/16 to f/8, we gain two full stops of light. Now the image will be far too bright, but we compensate for this by speeding up our shutter speed by two stops. When the ISO stays consistent, the aperture and shutter speed are inversely proportional. Whenever one lets in more light, in order to maintain a consistent overall exposure the other needs to let in less light. Using the same example, we’ll open up our aperture by another two full stops. We now have a surplus of two stops of light. In order to maintain the same overall exposure, we need to compensate by adjusting the ISO or shutter speed. In this case, we compensated by using a combination of ISO and shutter speed. By making the ISO one stop less sensitive, and by cutting the shutter speed in half, we have fully compensated for the change in aperture. In order to understand equivalents, you must first understand that smaller aperture values mean more light, smaller ISO’s mean less light, and that shutter speeds are annotated as fractions of a second (smaller fraction means less light). Practical Application Now that we have a basic understanding of overall exposure value, equivalent exposures, and how each variable affects an image, let’s talk about how go about using this knowledge when out shooting images! This section only applies to SLR users.
When this image of a South Dakota prairie dog was made, the above process was followed. I had a 280mm telephoto lens on my camera, so I knew that my depth of field would be pretty shallow due to my lens choice.
This image was made right after the first one. The sun had just come out from behind a cloud, so I needed to adjust my exposure accordingly. The second the sun came out from behind the cloud, I needed to check my overall exposure, even though I wanted to have shallow depth of field and a similar composition.
More to come. . . |
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