Buying a new digital camera can be a very overwhelming endeavor. Technology is in a constant state of change and there seems to be new camera announcements every month! There is a way to ensure that you purchase the right camera for your needs however. Understand the technology. Not all of it of course, but just enough to make the right decisions. This article will cover the features of digital cameras that are most important for you to understand.
To begin with me will discuss the similarities between film and digital cameras. Basically a camera is a light airtight box that allows exposure of a light-sensitive material through the use of a shutter and an aperture. This process is the same with either a digital or film camera.
Lenses focus the image and control how the photo will look (wide or telephoto); both film and digital cameras have lenses. The lens is also one of the most important factors in determining overall photo 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.
Film Advance, Lag and Response Time The digital sensor records light much like film. Once the light strikes film however, it is "exposed" and the camera must advance the film to the next frame to continue the process. With digital, the information that was captured during exposure is passed on to the processor and the sensor is freed up to record another image. The amount of time it takes for the sensor to "dump" its information and be ready to record again is called Advance Time. The digital camera's speed is also influenced by how many images it can store in the buffer 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). This means the camera will shoot 5 frames per second until the buffer fills up. The buffer will become full at 6 exposures if you are shooting RAW and 23 if you are shooting the highest quality JPEG.
When digital cameras first became popular, something called Lag Time was a major issue. The "lag" in between the time you pressed the shutter and the time the shutter opened was very noticeable. Recent advances in technology have reduced lag time significantly. Even most low priced cameras, have a very quick turn around time in between shots or during a series of quick exposures. If your photography requires fast shooting and many frames per second, it would be a good idea to check out the frames per second and lag time statistics before purchasing.
As with many things, this increased sensitivity does have its drawbacks. When using film you might get an excess of grain, with digital photography you get what is called noise. The grain you might see on your film, in most cases, is generally considered acceptable and even might be desired in some cases. On the other hand noise does not have the same allure. Unlike different emulsions of film, the sensor really only has one sensitivity. To manage an increased ISO, or during very long exposures, the camera must send more power to the sensor, which often will result in the appearance of small specks or dots of white or color. You will also sometimes see a blotchy look which is created from the higher ISO's or long exposures. Generally most of the noise is generally manifested in the darker areas of your photograph. If your photography requires higher ISO settings this is an important point to pay attention to; this often occurs during nighttime or long exposures. In higher priced cameras, manufacturers have spent the money to reduce the noise problem, but it still may present itself on the less expensive models. Look to reviews for how much noise individual cameras will produce.
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.
Resolution, probably the least understood and most talked about feature of digital cameras. The more the better, right? Well, most of the time. More resolution doesn't always mean better photographs.
These days almost all digital cameras have very high resolutions. Even the less expensive cameras all come with resolutions sufficient enough to make good 8x10-11x14 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 8x10. If you want to make larger prints you can move up to the 5 and 6 Megapixel cameras.
White Balance White balance refers to the processors ability to create "correct" color in your pictures. The digital camera sensor always captures "raw" information and then the onboard processor processes it and sends it to the memory card.
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 Understanding how the sensor works allows us to make informed decisions regarding resolution and camera speed. White balance is a fairly uniform feature across the entire line of cameras (with the exception of the high end models), negating any serious consideration in this arena. Given what we have covered I am sure you are wondering what other features exist that may influence your camera purchase?
Choose a digital camera that is right for you Understanding how the sensor works allows us to make some intelligent decisions surrounding resolution and camera speed. White balance is a fairly uniform feature across the entire line of cameras, negating any serious consideration in this arena. So what other features exist that may influence your camera purchase?
Along with the sensor and processor, lenses play a major part in creating high image quality. Luckily we are at a place in time where most lenses are of a very high quality. So 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 will allow you to shoot in lower light conditions without raising your ISO. It will also allow you to achieve a shallow depth of field, which will 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.
In general most beginner digital cameras do not provide a variety of wide angle lens choices. They will typically go down to 35mm or even 28mm but it is difficult to find a 24mm or wider. This problem is mainly due to the difficulties in building such a small focal length lenses. In this case, if you enjoy taking wide angle photos, you may want to think about upgrading to a digital SLR.
When it comes to long telephoto lenses the digital cameras have a big advantage to film cameras! 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 advantage to people who like to shoot "long". Please note, beware of cameras which claim their longest focal length as Digital Zoom. You should always avoid Digital Zoom. For these purposes we are concerned only with real or actual focal lengths.
The last lens specification to consider prior to purchasing is the focusing distance. If you like, or need, to shoot macro, look for a lens that has the ability to focus very close. They will usually be signified by a "macro mode" or be called "close focusing".
Shooting your digital camera in the field Taking photographs should be the fun part. It is important to not let all of the bells and whistles confuse you when you are out in the field. I agree that there are many choices and they can be a bit overwhelming. Here are three of the most important things you should always check before you start photographing.
ISO- Keep it set to a low (100 or 50) if you are outdoors or in areas where you have plenty of light. Raise your ISO only when you need to keep from getting camera shake. Most digital cameras provide great images all the way up to 400 ISO. If you need to go higher than 400 ISO, you may run the risk of introducing a noticeable amount of noise to your photos. Experiment with your digital camera to determine 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- Most cameras come with multiple resolution choices. Your choices may look like this: 2304x1728, 1600x1200, 1280x960, 640x480. The rule of thumb is to always choose the highest resolution. In this case that would be 2304x1728. The highest resolution will supply you with the highest quality images possible.
Digital Camera Accessories To say that there are a lot of accessories for the digital camera would be an extreme understatement! It can boggle the mind with all of the different options, cases, cards and storage units. There are however, 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 an ample amount of Flash Card storage, you will 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 you may want to consider a portable storage unit. The most basic form of storage is one that allows you to plug your card into the unit, and download your images. You can then put the card back into your camera, reformat it, and continue shooting. When you get home you simply attach the storage unit to your computer and transfer the images. Most of these units come with enough storage space for many days of shooting. I would consider a unit with at least 10Gb of storage.
Storage and transfer are the most basic functions which all of the models will perform. At this point they can get really fancy. There are units that will automatically create Cds from your cards, which produces an immediate archive of your images. Others come with an LCD screen that allows you to preview your photos right on the storage device. Advanced features will even allow you to organize your images into folders and albums. Prior to purchasing one of these units you may want to think about the length of time you will be away from your computer as you may not need one with these advanced features.
Extra Batteries / Charger Digital cameras run through batteries at an alarming rate. A definite purchase would be back up batteries. In this instance, rechargeable batteries are the intelligent choice because you will be using so many. Also, most digital cameras now come with a proprietary lithium battery with a charger. This is a good thing as it allows a stronger battery however you still would want a back up battery so you can continue to use your camera while one is charging. If this is your situation, 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 and a charger.
Bulb blower- If you are considering an interchangeable lens SLR this is a must as when you change lens on these types of cameras it is common to introduce dust into the camera body. Ultimately this will migrate to your sensor and embed itself as small blurry splotches on your final image. It is a smart investment of your time to spend a few seconds with the blower bulb which will save you hours on the computer cleaning up your photographs!
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