Purchasing a new digital camera can be a very overwhelming experience. Technology is continually changing and there seems to be upgraded cameras available every month! With these changes you can still ensure that you purchase the right camera for your needs by understanding the technology. You will not be able to understand all of it, however you can gain the knowledge to make the right decisions. This article will cover 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.

Shutters control the duration of the exposure in both types of cameras. Both film and digital cameras use an Aperture to control how much light hits the sensor during the time frame 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.

Whatever type of camera you may use, Focusing will always be a necessary step in creating sharp photographs. Manual and auto focusing can be found on both types of cameras.

Film Advance, Lag and Response Time The digital sensor records light much like film cameras do. The difference is that when light strikes film it is "exposed" and the camera must advance the film to the next frame in order to allow the user to take another photograph. With digital photography, the image that was captured during exposure is passed on to the processor and the sensor is then freed up to record another image. Advance Time is the amount of time it takes for the sensor to release its information and be ready to record again. The speed of the digital camera is also influenced by how many images it can store in its memory before the camera needs a time out to process them. A typical statistic you might find could be "23 full-res(resolution) JPEGs or 6 RAW images at 5 fps"(Canon 20D). In common language this means the camera will shoot 5 images 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 In traditional (film) photography ISO (or ASA) was the indication of how sensitive a film was to light. It was measured in numbers (you've probably seen them on films - 100, 200, 400, 800 etc). The lower the number the lower the sensitivity of the film and the finer the grain in the shots you're taking.

ISO One of the many benefits of digital cameras is the ability to change ISOs at any time. ISO refers to the sensitivity of the sensor in a digital camera and film in traditional cameras. The higher the ISO the less light you need to strike the film. With traditional cameras, if you needed to get a faster shutter speed because of low light or fast action, you needed to change to a higher ISO film. This could be wasteful or inconvenient at best. With digital cameras you can change the ISO on the fly. Now it is possible to be photographing outside in bright sunlight with a low ISO (for better color and image quality) and then walk indoors, change the ISO and continue shooting.

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.

Please remember, it is very common to see cameras that are equal in resolution but have different sensor sizes. In cases such as these it is a better idea to go for the larger sensor. Now you may be wondering, "how do you know how much resolution you do need?" It's simple really. You need to ask yourself how large of a print you want to eventually make. 3 and 4 Megapixel cameras are plenty sufficient for everything up to 8x10. If you need to create larger prints you will want to 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 camera processor processes it and sends it to the memory card.

The human eye is an amazing thing. What is even more amazing is that it is excellent at ignoring color casts. When we are indoors under typical house lighting the color is quite orange/yellow while office lighting (fluorescent) is very green. Our eyes are able to ignore this, but film and digital cameras faithfully record all color nuances. When using film photography it is often necessary to put filters on your camera or to purchase film that is balanced for the particular lighting (color) that you are using. With digital photography we can easily change the white balance. All digital cameras come with a good variety of choices for correcting typical lighting situations with white balance. They also generally include an auto setting as well which is useful if you do not know what kind of light you are working under. Typically the more expensive cameras will also include the ability to custom balance to any color light!

The human eye is excellent at ignoring color casts. When we are indoors under typical house lighting the color is quite orange/yellow, office lighting (fluorescent) is very green. Our eyes are able to ignore this, but film and digital cameras do not. They record faithfully. When using film it is necessary to put filters on your camera or to buy film that is balanced for the particular lighting (color) that you are using. With digital we can simply 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. This is useful if you do not know what kind of light you are working under. The more expensive models will come with the ability to custom balance to any color light!

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

Focal length is the next consideration you should think of before purchasing a digital camera. Do you like to shoot with wide-angle lenses? Long telephoto lenses? Do you enjoy shooting up close with macro lenses? Digital cameras have all the same lens options that your film camera does. It is simply a matter of choosing the camera with the qualities that you want. By looking through magazines or surfing on to the web and going to www.dpreview.com you can easily find the specifications that describe all of the options.

Two sets of specs are commonly given when you begin to look into focal length . The first set is generally the actual focal length of the lens. For example, 7mm-28mm. This example would be an extreme wide angle on a film camera. The digital camera however, has a smaller sensor area than 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 typically considered the 35mm equivalent. It is these numbers you should pay attention to when researching different cameras for focal range as they will be more recognizable 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 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 accessory is the type of storage medium that your camera uses to store your photographs. I prefer cameras that use Compact Flash as I have found this medium to be the best all around Flash Card. Compact Flash cards are sturdy, durable, not too small to lose or to big to be bulky. They also come in very large capacities-up to 8 gigabytes! Personally I recommend that people should have at least two cards in case one card becomes damaged or lost. How much you want to spend will determine your total amount of storage (cameras rarely ship with a card that is adequate for most photographic purposes). Having two 512Mb cards might be enough for most shooting situations, unless you take loads of photographs. 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 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- 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!