Purchasing a new digital camera
When it comes time to purchase a new digital camera you might feel a bit overwhelmed. With technology constantly changing and new features available every month it is easy to be confused about what to purchase. However, there is a way to ensure that you purchase the right camera that will meet your needs. The key is to understand the terms and technology. You might not understand all of it, however it is our goal to give you enough information to make an informed decision. This article covers the features of digital cameras that are most important for you to understand.
For starters we have to understand the similarities of film and digital cameras. In short, a camera is a light tight box that allows exposure of a light-sensitive material through the use of a shutter and an aperture. This definition does not change from film to digital cameras, nor does the process.
Both types of cameras have Lenses, which focus the image and control how the image will look (wide or telephoto). The lens is also one of the most important factors in determining overall image quality. The better the lens quality, the sharper and more clear your image. In film or digital photography- poor lenses=poor image quality.
Both types of cameras also use shutters to maintain the duration of the exposure. Both film and digital cameras need an aperture to control how much light hits the sensor during the period that the shutter is open. Very large apertures (2.8 or 4) will let in a lot of light, while small apertures (16 or 22) will let in very little light.
Whichever type of camera you may use, focusing the camera will always be an important step in creating sharp images. Manual and automatic focusing can be found on both types of cameras. So what are the differences between the two? The main difference is the way in which it records light. The traditional camera uses film and the digital camera uses a sensor and a processor. Understanding the differences between the sensor and processor is the key to understanding digital cameras.
Film Advance, Lag and Response Time The digital sensor takes in light much like film. Once the light strikes film it becomes”exposed” and the camera must advance the film to the next film frame to carry on the development. With digital cameras, the information that was acquired during exposure is moved on to the processor and the sensor is then freed up to grab another image. The length of time it takes for the sensor to “unload” its information and be ready to record again is called Advance Time. The speed of the digital camera is also influenced by how many images it can retain in the memory before the camera needs a time out to process them. A typical statistic could be “23 full-res(resolution) JPEGs or 6 RAW images at 5 fps”(Canon 20D). All this means is that the camera will shoot 5 frames per second until the memory fills up. The memory will become full at 6 exposures if you are shooting RAW and 23 if you are shooting the highest quality JPEG.
Something called Lag Time was a major issue when digital cameras first became popular. The “lag”, or amount of time, in between the time you pressed the shutter and the time the shutter opened was very noticeable. Fortunately with recent advances in technology lag time has reduced significantly. Today even most of the budget friendly cameras have a very quick turn around time in between shots or during a series of quick exposures. To sum it up, if your photography requires fast shooting (i.e. sports photography) and requires many frames per second, it would be a good idea to do some research and check out the frames per second and lag time statistics before purchasing a camera.
ISO The ability to change ISOs at any time is one of the many benefits of digital cameras. ISO refers to the sensitivity of the sensor in a digital camera and film in traditional cameras. The higher the ISO setting the less light is needed to strike the film. With traditional film cameras, if you wanted to get a faster shutter speed due to low light or fast action, you needed to change to a higher ISO film. At best this could be wasteful or inconvenient . The nice thing about digital cameras is that you can change the ISO as you go. With digital cameras it is possible to be photographing outside in bright sunlight with a low ISO (for better color and image quality) and then walk indoors, you can easilty change the ISO and continue shooting.
In Digital Photography ISO measures the sensitivity of the image sensor. The same principles apply as in film photography - the lower the number the less sensitive your camera is to light and the finer the grain. Higher ISO settings are generally used in darker situations to get faster shutter speeds (for example an indoor sports event when you want to freeze the action in lower light) - however the cost is noisier shots.
Resolution Resolution is probably one of the most talked about but least understood features of digital cameras. Most people believe the higher the resolution the better. This is true, generally speaking. However more resolution doesn’t always mean better photographs.
In today’s market almost all digital cameras have very high resolutions. You can even find less expensive cameras with resolutions sufficient enough to make a decent 8×10 or 11×14 prints. Given this you might be asking, “what is the big attraction to higher resolutions?” For the most part it is a selling point for the manufacturers! More resolution is good but what is even better, and what you want to look for in your camera, is a larger sensor size. Here the bigger the better manta comes into play. Sensor size is a much better measure of the camera’s final image quality. In film cameras, a 35mm is better than an APS camera because the size of the image on the film is bigger. There is no difference with digital cameras.
These days almost all digital cameras have very high resolutions. Even the less expensive cameras all come with resolutions sufficient enough to make good 8×10-11×14 prints. So what is the big attraction to higher resolutions? Mostly, it is a selling point for the manufacturers! More resolution is good but what is even better, however, is a larger sensor size. The bigger the better. This is a much better measure of the camera’s final image quality. In film cameras, a 35mm is better than an APS camera because the size of the image on the film is bigger. No different with digital cameras.
Remember, it is common to see cameras that are equal in resolution but have different size sensors. In this case I would go for the larger sensor. So how do you know how much resolution you do need? Simple really. Just ask yourself how large of a print do you want to make. The 3 and 4 Megapixel cameras are plenty sufficient for everything up to 8×10. If you want to make larger prints you can move up to the 5 and 6 Megapixel cameras.
The human eye is excellent at ignoring color casts; however film and digital cameras do not ignore the differing light castings such as how indoor colors under typical house lighting show the color as quite orange/yellow while office lighting (fluorescent) is very green. Cameras record colors quite faithfully. When using film it is important to put filters on your camera or to purchase film that is balanced for the particular lighting (color) that you are using. With digital cameras we can easily change our white balance. All digital cameras come with a fine selection of white balance options for correcting typical lighting situations. They all will include an auto setting as well as manual settings. Automatic settings are useful if you do not know what kind of light you are working under. The more expensive cameras come with the ability to custom balance to any color light!
So if your light is Then the color is Choose this White Balance for good color Daylight Neutral (”white) Daylight Late Afternoon/Sunset Warm (yellow/orange) Daylight Early Morning Warm (yellow/orange) Daylight Cloudy Cool (blue) Cloudy/Overcast Open Shade Very Cool (blue) Open shade Unknown Light source ??? Auto Tungsten/Incandescent Very yellow/orange Tungsten/Incandescent Fluorescent Green Fluorescent
Choose a digital camera that is right for you Hopefully by now you recognize that understanding how the sensor works will enable us to make some intelligent choices regarding resolution and camera speed. We also know that white balance is a fairly uniform feature across the entire line of cameras, negating any serious consideration in this arena. So you might be wondering what other features exist that may influence your camera purchase?
Lenses Lenses play a major part in creating high image quality, along with the sensor and processor. Luckily in todays marketplace we are at a place in time where most lenses are of a very high quality. So we now know that speed and length are the qualities that you should look at. Speed refers to the fastest -stop of the lens. 2.8 is faster than 3.5, which is faster than 4. A faster lens allows you to shoot in lower light conditions without raising your ISO. It also allows you to achieve a shallow depth of field, which should result in a blurred back or foreground.
Buying a new digital camera
The next item you need to consider is focal length. Do you prefer to photograph with wide-angle lenses? Long telephoto lenses? Do you enjoy shooting up close with macro lenses? Film and digital cameras both come with all of the same lens options. It is simply a matter of choosing the camera with the qualities that you want. Doing some research through reading magazines or surfing on to the web and visiting sites such as dpreview.com will allow you to easily find the specifications that describe all of the options.
When it comes to focal length it is important to remember that two sets of specifications are generally given. The first is usually the actual focal length of the lens. For example, 7mm-28mm. This would be an extreme wide angle on a film camera. The digital camera however, has a smaller sensor area then the film camera which makes the 7mm lens look more like a 35mm lens. So the second set of numbers on this lens would be 35mm-136mm. This is generally called the 35mm equivalent. When looking for a digital camera these are the numbers you should pay attention to when checking for focal range as they will be more familiar to you.
Many amateur digital cameras do not provide a wide spectrum of wide angle lens choices. Most will commonly go down to 35mm or even 28mm but rarely can you find a 24mm or wider due to the difficulties in building such a small focal length lenses. So if you enjoy wide angle photography you many want to think about moving up to a digital SLR.
When it comes to long telephoto lenses, however, the digital cameras have a big advantage! Their smaller sensor size turns even moderate telephotos into very long lenses. For example a real 57mm focal length behaves like a 370mm! This is a real boon to folks who like to shoot “long”. Beware however of cameras which claim their longest focal length as Digital Zoom. Digital Zoom should always be avoided. We are concerned only with real or actual focal lengths.
Focusing distance is the last lens specification to consider. If you desire to shoot macro, please look for a lens that focuses very close. They will usually be signified by a “macro mode” or be called “close focusing”.
Shooting your digital camera in the field Shooting your digital camera should be the fun part. Do not let all of the bells and whistles confuse you out in the field. There are many choices and they can be a bit overwhelming. Here a are three of the most important things you should always check before you start photographing.
ISO- If you are outdoors or in areas where you have plenty of light keep the ISO set to a low (100 or 50). Raise the ISO only when you need to prevent camera shake. Typically most digital cameras will provide great images all the way up to 400 ISO. If you need to go higher than 400 ISO, you must know that you may run the risk of introducing a visible amount of noise to your photos. Take some time and play with your digital camera to figure out which ISO produces unacceptable noise levels.
Jpeg vs. Raw- This is an easy choice. If you want to manipulate every photograph in your computer, shoot RAW. This format is much more flexible and enables you to correct errors in exposure and color cast without downgrading the quality of your image. If you do not have the time or desire to work on every image, then use the highest quality Jpeg mode. Jpeg mode uses a minimum amount of image compression and provides extremely high quality pictures.
Image Size- Many cameras automatically come with multiple resolution choices. The options may look like this: 2304×1728, 1600×1200, 1280×960, 640×480. Basically, always choose the highest resolution. In this case that would be 2304×1728. This setting will supply you with the highest quality images possible.
Digital Camera Accessories It is an understatement to say that there are a lot of accessories for the digital camera! It boggles the mind the number of choices available such as cases, cards and storage units. Not all of the accessories are a necessity, in fact there are only a very few accessories that are absolute necessities.
Compact Flash-The first is the type of storage that your camera uses. Personally I prefer cameras the use Compact Flash storage option. This medium seems to be the best all around Flash Card. These cards are sturdy, durable, and not too small to lose or to big to be bulky. It also comes in very large capacities-up to 8 gigabytes! I recommend you have a least two cards on the off chance one becomes damaged or lost. The total amount of storage available to you will be determined on how much you want to spend on your cards (cameras rarely ship with a card that is adequate for most photographic purposes). Having two 512Mb cards seems to be adequate for most shooting situations, unless you are very trigger happy. Having 4 of these cards or two 1 GB cards will ensure that you will never be without storage.
Portable Storage-If you have invested in enough Flash Card storage, you will probably not need a portable storage unit. This is however contingent on downloading your cards on a daily basis. If you are in a situation where you will not have access to your computer for long periods of time (in order to upload your photos from your camera to your computer) you may want to consider a portable storage unit. The idea of a Portable Storage unit is to move your photos from your Flash Card to the storage unit thereby freeing up space on the card. You can then put the card back into your camera, reformat it, and continue taking pictures. When you return home you simply attach the storage unit to your computer and transfer the images to your computers harddrive. Most Portable Storage units come with enough space for many days of shooting. A recommendation would be to purchase a unit with at least 10Gb of storage.
Storage and transfer are the most basic function which all of the models will perform. From here they can get really fancy. There are units that will automatically burn Cds from your cards, which produces an immediate archive of your images. Others come with an Lcd screen that allows you to view your images right on the storage device. Advanced features will even enable you to organize your images into folders and albums. Think about the length of time you will be away from your computer before purchasing one of these storage units. You may not need one.
Extra Batteries / Charger Digital cameras go through batteries at an alarming rate. You will definitely need to have back up batteries. Given that you will go through so many batteries, rechargeable batteries are the intelligent choice. Most digital cameras come with a proprietary battery with a charger. This is helpful as it allows a stronger battery. If this is your situation, it is a good idea to purchase extra batteries when you buy your camera. If your camera is powered by common AA batteries, you would be wise to buy a couple sets of rechargeable batteries.
Bulb blower- this is a must if you are considering purchasing an interchangeable lens SLR. Often when you change the lens on these cameras dust is introduced into the camera body. Ultimately the dust will migrate to your sensor and manifest itself as small blurry splotches on your final image. A few seconds with the blower bulb will save you hours on the computer cleaning up your photographs!