|
|
The Features You Need In An SLR CameraJul 22 '00 Write an essay on this topic.There are so many different types of cameras available that I'm going to choose a specific type, the SLR (Single Lens Reflex) camera. I'm also going to concentrate only on the body of the camera; I will make only a few comments about the lenses. I'll go through the common features and tell you which ones you need or don't need, and why. First of all, SLR cameras are generally designed for people looking for a little more control over their pictures compared to a point-and-shoot camera. If you're not sure that an SLR is right for you, look at some of the other great Epinions advice in this section. Also, keep in mind that I'm targeting the beginner to amateur photographer in this article. There will, of course, be some information that is valuable to others. So, now that you are still reading, you must be interested in learning more about SLR features. First, I'll discuss some general guidelines to go by when choosing an SLR camera. Then, I'll list a bunch of common features provided by SLR cameras, and discuss what the feature does, who needs it, and why. I'm not going to discuss particular models or even brands of cameras in any depth. (I will say a few things in the next section.) Also, my experience is with 35mm SLRs, though this information may apply to other formats. General Guidelines One of the most important things to remember when choosing an SLR camera body is that you are not purchasing the body in isolation. You are also buying in to a whole family of lenses. Lenses from one camera manufacturer typically don't fit on camera bodies from another manufacturer. So once you have a Nikon body, for example, with a set of lenses, it will be difficult (and expensive) to switch to another brand of camera. Most name-brand lenses today are of exceptional quality (*), but if there's a particular reason that you like one brand of lenses (for example, bigger selection or cheaper prices), then keep this in mind when choosing a body. Nikon and Canon are probably the most commonly-chosen camera bodies among professionals, but Olympus, Pentax, and Minolta make fine cameras as well. (*) (Third-party lenses are sometimes of lower quality than the camera manufacturers', but this is not always the case. Check reviews before buying any lens!) Here's a good way to choose a camera body. Go through my list of features below and choose the features that you think will be most important to you. Then, get a list of features from a bunch of cameras. (You can usually find this on the manufacturer's web site, in ads for magazines, or in product information at your local camera store.) Find the cheapest camera that supports all of the features you are interested in (or the camera that comes closest), and buy that one. Notice that I said the cheapest camera. The reason I said that are two-fold. First, all modern name-brand cameras are very well built; you won't get shoddy cameras by going with a cheaper model. And second, it's much easier to replace a cheaper model if it's damaged than an expensive one. If you have a cheap camera, you're more likely to risk it to get that great shot, and that's what photography is all about. It's not about having an expensive hunk of metal that you're afraid to take out in the rain. Finally, the most important thing to do is take your time. You are making a large investment, so you want to make sure that you've considered all the options. Once you narrow down your choices to several cameras, find a local camera shop that rents out camera equipment. Take each of the models that you are considering out for a few days of shooting, and see how they feel in your hands. You'll probably learn a lot more about the camera by trying it than by reading about it! Glossary Following are some terms that you may not be familiar with. Shutter speed - The amount of time, in seconds, that the shutter is left open when exposing a photo. Aperture - A measure of the size of the lens opening. This controls the amount of light getting to the film and also the depth of field. Depth of field - The range within which objects in the picture are in focus. Stop - I use this term when talking about exposure. It refers to the amount of light entering your camera. Increasing the exposure by 1 stop means that you are doubling the amount of light. Decreasing by 1 stop means that you are halving the amount of light. This is controlled by changing the shutter speed on your camera, or the aperture on your lens. Filter - A piece of glass or gel that can be placed in front of your lens to produce certain effects. Tripod - A set of three metal legs that hold your camera steady. ISO - International Standards Organization. ISO ratings on film rate their "speed", or sensitivity to light. Fast films are more sensitive to light than slow films. ISO numbers are typically in the range 50 (slow) to 1600 (fast), though you may find film outside that range. Meter - A light sensitive device in your camera that determines what it thinks the correct shutter speed and/or aperture is to exposure correctly. Features Now I will discuss the common features of SLR cameras and tell you which ones are important and why. Auto focus This is probably the biggest difference between all of the SLRs you will look at. There are good reasons to have auto focus, and there are good reasons to have manual focus. The primary advantage of auto focus is self explanatory; it focuses for you. Many people don't want to have to worry about focusing, or they don't have enough time to focus (for example in action photography). These are great reasons to have an auto focus camera. However, there are some situations where auto focus can be a hinderance. For example, in macro photography (taking pictures of very small objects), your idea of what should be in focus is often contrary to what the camera thinks should be in focus. There are also times where you disagree with what the camera chose to be in focus. In these situations, you have two options: use a manual focus camera or use your auto focus camera with the auto focus turned off. The first option is, again, self explanatory. Manual focus cameras require that you focus every picture yourself. I will discuss this option in more detail shortly. If you think you will be using your auto focus camera with the auto focus turned off, then you should try out the camera in the store and look for the following things: 1. Can you turn off auto focus easily? For many cameras, there is a switch on the body or the lens that will do this. 2. Once auto focus is off, can I focus easily? This may be more a function of the lens than the bodies, but certain body styles usually have consistent lens function. On some auto focus lenses, you may find that the focusing ring (the ring that you turn to adjust the focus) is harder to reach than on manual lenses. 3. Can I tell if the image is in focus in the view finder? Most (if not all) auto focus cameras do not include any focusing aids in the view finder of the camera. This can make it difficult to get your image precisely focused. Manual focus cameras have their own advantages and disadvantages. First, these cameras put you in complete control over focusing. This lets you focus on exactly the region you want, but it also slows you down because you have to focus every time. After working with a manual focus camera, focusing will eventually become second nature, and you won't ever have to worry about getting an image back and finding that the main subject is out of focus (unless you did a poor job of focusing yourself!). Personally, I prefer my manual focus camera, but I have certainly been in situations where auto focus would have been a help. If you are interested in auto focus, there are a number of advanced technologies available that can improve the camera's ability to focus precisely. These include predictive auto focus (for moving objects, the camera predicts where the object will be precisely when the shutter is released), multi-point auto focus (the camera looks at multiple spots on the image to determine where the focus should be), and even eye tracking (the camera tracks your eye movement to determine what should be in focus). You should judge for yourself whether you will find these useful (and whether you can afford them!). Shutter Speed Most cameras support shutter speeds from 1 second to 1/1000 of a second. You may need shutter speeds faster than 1/1000 if you are shooting with a fast lens (a lens with large aperture) and/or fast film on a sunny day. If there is too much light, you can always restrict the amount of light coming in by using a smaller aperture or a neutral density filter. (Polarizing filters will do this also.) I've never found a need to have faster than 1/1000 shutter speed, but if you shoot very fast-moving subjects, you may find that it is helpful. On the other end of the scale, it's often useful to have very long shutter speeds. If you use anything less than 1/30 of a second, you will need to be using a tripod. (If you won't be using a tripod, then this is not important to you.) Most cameras provide a "bulb" setting, which will let you hold the shutter open for as long as you wish (or until the battery dies!). You'll need to use long shutter speeds when you are shooting in low light without a flash, and/or using slow film, and/or using a very small aperture (f/22, for example). For greater control, you may prefer to get a camera with half-stops (or even third-stops) on the shutter speed. This will allow you to more finely control the exposure of your image. I have found that, when using slide film, 1 stop accuracy is often not enough. Some cameras will provide 1 stop accuracy in manual mode, but 1/2 stop accuracy in automatic mode (for example). See my section on exposure compensation below. Exposure Modes Manual exposure mode is the most commonly supported. You set both the shutter speed and the aperture manually. Aperture priority allows you to set just the aperture and let the camera pick the correct shutter speed. This is very handy to quickly pick the correct exposure for a shot. Shutter priority allows you to select the shutter speed, and the camera picks the correct aperture. This is very useful when you need to have a specific shutter speed (for example, if you are not using a tripod, you need 1/60 or faster, or if you are taking pictures of action, you want to ensure a certain shutter speed). Fully automatic mode will automatically pick the shutter and aperture settings for you. If you're taking pictures where you don't have time to change settings on your camera, this will work great. Some cameras supply different automatic settings, such as portrait, landscape, closeup, and others. These modes pick the shutter speed and aperture that will probably make the picture be exposed the best. If you find yourself using this mode all the time, you're not taking full advantage of the control offered by an SLR camera, and you may want to look at a simpler point-and-shoot. Most people find that aperture priority or shutter priority is the most useful for them, while some prefer manual. Try out some cameras and see which one you find easiest to use, and make sure that the camera you buy has that. Exposure Compensation This very important feature allows you to use aperture priority or shutter priority modes and modify the exposure that the camera picks. For example, you can set your camera to aperture priority and use the exposure compensation feature to overexpose by 1 stop. (You would want to do this, for example, when taking pictures of bright snow.) Some cameras will provide greater accuracy in the shutter speed and/or aperture setting while in automatic mode. For example, a camera may provide 1 stop increments when setting the shutter speed manually, but when using the automatic mode, it will pick the shutter speed in 1/2 stop increments. Some cameras will even use "stepless" shutter speeds, which means it will pick the exact shutter speed needed. For print film, I would suggest at least 1 stop accuracy in automatic mode with exposure compensation. For slide film, I would suggest at least 1/2 stop accuracy in automatic mode with exposure compensation. Film Speed Setting Most modern cameras will support DX-coded film. This means that it reads the film speed off of the film canister. (Look at the side of a roll of film and you will see a bunch of silver squares. This is the DX encoding.) If you don't have this feature, you will need to set the film speed by hand whenever you load a new roll of film. An important feature to have is the ability to change the ISO rating of your film "on-the-fly". Why would you want to do this? There are several reasons. First, many people shoot film at a different speed than what the film calls for. For example, they may shoot Velvia (ISO 50) at EI 80. (EI means "exposure index". It is the speed that you actually use when shooting pictures.) When they get the film developed, they will tell the lab what EI they used, and the lab will compensate in the developing process. This is called "pushing". Another reason to change the ISO setting is for determining exposure for very dark subjects. If you are shooting with 100 speed film, and your camera's meter only goes to 1 second, it may be too dark to find out the correct exposure. If you set your ISO rating higher than 100, however, it might allow your camera to give you a reading. You can then calculate how long to expose your picture for. Depth of Field Preview This is an absolutely essential feature. Why some camera models don't provide it is beyond me! The depth of field preview lever (or button) shows you what your image will look like at the current aperture. It will also make the image in the viewfinder darker. Using this lever, you can tell which parts of your image will be in focus, and which ones will not be. Without it, you must make a guess or do some calculations and measurements. Personally, I'd rather just look through the lens! Multiple Exposure Here's a feature that can produce some interesting results. What this allows you to do is shoot multiple images on the same frame of film. Why in the world would you want to do this? There are lots of reasons! You could shoot the same scene, one with someone in it, and one without anyone. The result will be a "ghost". (You'll need a tripod to do this.) Or, you could shoot the moon and then shoot a picture of something else on top of it. So the moon goes where ever you want in the sky! Or you could create an "earth quake" effect by shaking the camera while taking a bunch of pictures on the same frame. And there are numerous artistic effects you can create. The possibilities are endless. This feature isn't necessary, but it can be a lot of fun. Film Loading / Advance / Motor drives There are basically two types of film handling in cameras: manual and automatic. With manual film loading, you put the film in the camera and then take several blank shots (for example, shoot at 1/1000 second with the lens cap on). Usually the camera will tell you which frame you are on, so shoot empty frames until it reads "0" or "1". Some people claim that they can get more frames from a roll of film if they advance it manually. With automatic film loading, you put the film in the camera like a manual camera, but the camera takes care of advancing the film to the start position. Manual film advance requires you to pull a lever between each picture. Automatic film advance advances the film for you. Automatic advance lets you take pictures more quickly, and you also don't have to worry about whether or not you've advanced the film. Some cameras come with (or can be fitted with) motor drives. These allow you to take shots very quickly, anywhere from 2 frames per second to 4 frames per second (and faster). This can be valuable when doing model photography; you can pick the shot where the model had exactly the right expression. Or in action photography, this has obvious advantages. For most people, this isn't very important. Most new cameras have automatic film advance, but manual film advance is easy to get used to. Motor drives are only necessary if you know you will need them. Auto bracketing Some cameras with automatic film advance offer a feature known as auto bracketing. This allows you to take 2 or 3 shots of the same scene, but with different exposures. For example, you could take a shot with the meter, a shot 1 stop overexposed, and a shot 1 stop underexposed. I don't think this is a very useful feature because you can bracket very easily yourself. If you find yourself bracketing a lot, then you are avoiding learning how to expose your images correctly. Viewfinder Display It is important that the camera's viewfinder includes enough information. When looking through the viewfinder, you should be able to tell the following: - What mode am I in - manual, aperture priority, or shutter priority? - What is the camera's suggested shutter speed for my chosen aperture? - What is the current shutter speed that I have set? Most cameras will provide this information, and possibly much more. When trying the camera in the store, pay attention to this. Without this information, you will have to go back and forth between looking at the dials and looking in the viewfinder. For manual focus cameras, it is very important that the viewfinder display include focusing guides. These guides usually come in three forms - matte background, microprism field, and split-image field. When using the matte background, turn the focusing ring until the image is in focus. With the microprism field, turn the focusing ring until the "glitter" disappears from the field. With the split-image field, turn the focusing ring until the two images in the prism line up exactly. If you will be focusing manually, these focusing guides are essential. Most (if not all) auto focus cameras only have the matte background, so it can be harder to focus manually using those cameras. Weight If you will be carrying around your camera, pay close attention to this. Although it may not seem too heavy at first, it may start to feel pretty heavy after carrying it around the city or country all day. Many people prefer to have two cameras for this purpose - a small point-and-shoot, and a good SLR. That's a fine way to do it, but make sure you consider what you will do when you get tired of carrying around your SLR. Flash Flash is not very important to me, as I take most of my pictures with natural light. However, if you take a lot of pictures indoors or in low light, you may find that you need a flash. I don't know a whole lot about flashes, so I will defer this topic to my fellow Epinion-ites. Conclusion There are a whole lot of features available on modern SLRs, and it can be overwhelming when you're trying to find one that does what you want. I hope that I've helped you decipher all the features and encouraged you to take the time to consider your purchase carefully. References Here are some web sites to look up model information on some SLRs. Pentax - www.pentax.com Minolta - www.minolta.com or www.minoltausa.com Olympus - www.olympus.com or www.olympusamerica.com Nikon - www.nikon.com or www.nikonusa.com Canon - www.canon.com To get a feel for the prices, try out these web sites. B&H Photo Video - www.bhphotovideo.com Camera World - www.cameraworld.com Marine Park Camera & Video - www.marineparkcameras.com I would also suggest looking at the ads in Peterson's Photographic magazine (You can subscribe online at www.photoalley.com).  |
| Read all comments (6)|Write your own comment |
|
Ads by Google
|
