Choosing a digital camera - Everything to look for! The range in features, purpose, and prices of digital cameras varies greatly. Similar to purchasing family transportation, you do not want a motor scooter for a family of ten nor a bus when you will only transport you and your wife. The first thing that you need to do is decide what size prints that you will be happy with. Print quality is expressed at PPI or Pixels Per Inch. Quality really begins to fall off when you fall below 200 PPI. Magazines usually demand 300 PPI for photo quality. Most consumers will be satisfied with 200 PPI or above although at 200 PPI or below your prints will begin to get a bit fuzzy. The effective maximum print size can be determined quite easily. Just look at the manual that comes with the camera and divide the dimensions by 300. If you have a camera that produces a maximum image that is 3008 X 2000 pixels (6 mega pixels) then you can calculate the dimensions of the size of a true photo quality print by dividing each side by 300 to arrive at 10.02" X 6.67". Near photo quality for the same is calculated by dividing each side by 200 or 15.04" X 10.00". Anything above that will yield fuzzy or pixilated prints. If you are handy with an image program that will resample (Photoshop, Photoimpact, or GIMP for example) then you can slightly increase the size of your printed output by resampling your image to a larger size. Basically if you do mainly 5" X 7" and an occasional 8" X 10" then look at around 6 mega pixels. Demands for pictures for the WEB and Email are much lower. Make your mega pixel decisions based on printed size. The next thing to consider is the sensitivity of the camera. The actual electronic device that is inside the camera is called the CCD and range in size from very tiny to much larger. The surface area of the sensor is what is available to catch the light. The larger the sensor the more light shines on its surface. A good analogy is which will catch more rainwater on a rainy day a teacup or a bucket? The ISO Speed setting on the camera is the equivalent of the ISO Speed rating on conventional film. The higher the ISO rating of the film or digital setting means the lower the light that is required to take the picture. The problem is that at higher ISO settings the sensors begin to introduce noise. This is like listening to a distant radio station. When you turn up the volume on the radio you not only amplify the signal but the background noise. The same thing is true with the sensor in a digital camera. When you amplify a weak signal that is due to low light levels then you amplify the background noise that is inherent in any electronic device and that produce artifacts in your image. In daylight you want to shoot mainly at ISO 100 or ISO 200 for a normal subject. For sports or other fast moving subjects or in low light situations you want to be at ISO 400 or above. You will want to check at what point the digital camera that you are looking at will introduce noise into the image. If your digital camera introduces noise at anything above ISO 200 then you will be limited to sharp pictures in daylight and with limited action. If it performs well at ISO 400 or ISO 800 then you can be assured that the camera’s sensor speed is sufficient. Basically choose a camera that performs well at ISO 400 or above. Choose good quality optics (lenses). Names like Zeiss Ikon , Minolta, and so on that label today’s optics may or may not be the actual manufacturer of the lenses but might refer to a quality standard for the optics that bear their name. It is generally better to choose a camera that bears one of these trade marks because it assures that the better low dispersion coatings and higher grade glass is present as well as higher quality lens grinding. Generally choose a camera built by a camera manufacturer and not a company that is either new to the game or a part time camera manufacturer. This has a very sound reasoning behind it! The software that is present inside the camera that builds the image coming off the CCD required a great deal of refinement and perfection in design. Generally the light is received on the CCD into photo sites. The CCD is approximately half green sensitive and a quarter red and a quarter blue sensitive just like the human eye. The image is generated with a routine called the Bayer Algorithm and generates an approximation of what it has actually seen. The better the algorithm the better the image with fewer artifacts and other image distortions. You can be assured that Nikon, Canon, Fuji, Kodak, and other of the major camera manufacturers have their image building software refined and highly tested. In fact these are highly guarded corporate secrets! Choose a name brand! If possible take a test shot with the camera or view through the electronic viewfinder or screen and see if the colors are well saturated and the skin tones are representative of the actual scene. Skin tones are most important to the human eye. If the skin tones are correctly represented then it passes. Next is the viewfinder. If the camera only has an electronic viewing screen it should be very bright. On sunny days these are often very hard to see and even the brightest are difficult. They electronic viewfinders that you place up to the eye are better because they restrict ambient light but they both share a common problem and that is that they only see what the camera sensor sees so in many night shots where it is very dark and the camera relies on the flash for the total light source the sensor sees nothing. Optical view finders outside the taking lens are great but they suffer from a problem called parallax. This is where the viewfinder sees something different from the taking lens especially at very short distances. The best viewing system for digital cameras is where you view through the taking lenses and this is generally referred to as DSLR. The DSLR system uses a mirror to reflect the light from the taking lens through a prism to the eye of the photographer. The DSLR (Digital Single Lens Reflex) is by far the best viewing system but is only found in the most expensive cameras. DSLR viewing systems offer another advantage. By showing exactly what the sensor sees they can preview depth of field. This is where the depth of focus changes as the aperture size changes. There is generally a control on the camera that allows the depth of field to be previewed prior to actually taking the picture. Next is how the camera stores the images. I am sure that you have heard of JPG or JPEG images. This file type is an abbreviation for Joint Photographic Experts Group. This image type was created as a result of analysis of how an image tonal range and color range could be reduced without detection by the human eye. The JPG processor within the camera actually reduces and compresses what has been captured by the image sensor so that the images are smaller and more can fit on the storage medium.The good thing is that the images are smaller but the bad thing is that many of the tones and details of the image are thrown out to save space. On the better cameras an option exists to save the images in an uncompressed format such as TIFF or as RAW. In the RAW format you are capturing exactly what the sensor sees and are saving it all. This is mainly for the experienced or professional photographer that intends to process the image on their own instead of having the camera do generic processing. Usually the JPG format is fine for the vast majority of the cases. A very important consideration is what kind of memory medium the camera requires. You generally cannot go wrong with SD Cards (Secure Digital) or Compact Flash Cards. Often the camera will require a medium that is either obscure or proprietary in nature. These often can greatly increase the cost of picture taking. Check to see if the memory medium is generally available and at what cost. Another very important factor is the internal flash on the camera. Usually these flashes are very weak. You should check to see if the camera has a ‘Hot Shoe’ so that an external or ‘add on flash’ can be used. CRITICAL! CHECK THE SYNC VOLTAGES OF THE OLDER FLASHES BEFORE PLACING THEM ON THE HOT SHOES OF THE NEWER CAMERAS! OLDER FLASHES OFTEN USE HIGHER SYNC VOLTAGES THAT WILL FRY THE SYNC CIRCUITS IN THE NEWER CAMERAS! YOU MIGHT NEED A SPECIAL ADAPTER LIKE A WEIN SAFE SYNC TO PROTECT YOUR CAMERA! On the internal flashes check the guide number to see the effective range of the flash. See if it is powerful enough to take pictures of the ranges that you desire. Look at the exposure metering system. Does the camera allow for Spot, Center Weighted, and Matrix metering? These are important considerations for the more advanced photographer. Look at the manual capability of the camera. Does it allow manually adjusting shutter speed, aperture, and so on? The more advanced photographers will require these and if they are not available then they cannot be used. Does the camera record EXIF data? This is handy data that cannot be seen other than with software that records dates, times, settings, and so on about pictures that have been taken. Does the camera allow for histograms? These are important tools for any photographer. Usually you cannot rely on the viewing screen to give you an accurate representation of the picture that was just taken. The histograms are easy to read and will tell you if highlights were lost or data in the shadows is gone. Batteries are often an overlooked feature of the camera. Often a camera is purchased only to find that the cost of an extra battery (or a replacement) is half the cost of the camera! Generally try to stay with cameras that use AAA type batteries or AA batteries. These can be purchased as rechargeable and are very cost effective. Look at the menu system on the camera. Is it easy to operate and understand? Is it fast to get to important changes that you need to make in the camera settings? Remember that this is something that you will have to live with for a long time. Movie mode, sound recording, and all that stuff is the buyers preference. It was never important to me! Size and cost are completely purchaser decisions. Size can be very important in that you might want to carry the camera in a shirt pocket so that you are not dragging around a camera or camera bag. I hope that I have explained this completely. Good luck with your purchase!