Two of my daughters expressed an interest in a digital camera for the holidays so I have been shopping around. There is a myriad of techno-babble terms being bantered about in describing digital cameras that may require some explanation here so all can understand.
The primary feature being touted by digital camera makers is “megapixels”, or millions of tiny dots of resolution. A “pixel” is the common vernacular for “picture element”, which is each tiny dot of information that you see on your computer screen. To put megapixels in perspective, a computer monitor with the common 800x600 resolution means 800 pixels wide by 600 pixels high, or 480,000 pixels. Likewise a 1024x768 resolution, common on today’s 17 inch monitors, is 786,432 pixels. If the primary intent is to email digital photos, or post them to the web, then very high resolutions are unnecessary. Someone recently sent me a huge image file as an email attachment. The picture was of a new grandchild, and taken with a 2.1 megapixel camera, at maximum resolution. The sender did not practice good “netiquette” and reduce the size of the image to reasonable dimensions (such as 320x240 or 640x480), so his large image was three times the size of the screen on my 17 inch monitor. The only way to view the unedited image was to scroll left and right, and up and down. In most cases there is little need to take photos at the maximum resolution; almost all cameras allow for smaller, lower resolution photos.
If the user wants to print the photos with a photo grade printer on high quality inkjet or laser photo paper, 2.1 megapixels, can produce an excellent quality 5x7 inch print, and a reasonable 8x10 inch print. Many of the moderately priced digital cameras are now being offered with 5 or more megapixels. With an appropriate printer and paper, 5 megapixels can produce an excellent quality 8x10 print, and a decent 11x17. The holy grail of digital cameras, 12+ megapixels, the resolution of good quality slide film, was passed about two years ago by the high end professional models. Many professional photographers, who dismissed digital photography as a low quality fad a few years ago, are now embracing the new technology.
The ability to zoom the image in and out is a popular feature in most cameras. The two methods of zoom available on digital cameras are optical and digital zoom. In terms of sharpness, optical zoom is superior to digital, as the image itself is manipulated, rather than the pixels making up the image. The less expensive cameras typically only offer digital zoom (adequate for common snapshots), but the better cameras offer either optical zoom or a combination of the two.
The memory available to the camera determines how many images it can hold before the data must be downloaded to a computer or other device. Most digital cameras have some built-in memory, and allow for the addition of supplemental memory in a variety of formats. Some cameras minimize the need for digital memory by writing the image directly to a floppy disk or mini-CD. Since the integral memory in a digital camera can typically hold only a small number of images, it is important to determine the price and availability of additional memory in the proper format. Memory comes in different capacities and formats from tiny cards, to rectangular “memory sticks”. All camera memory is not the same, and differs in speed (faster is better, but often at a price), and power consumption (less power consumption is better by prolonging battery life). According to Lexar, one of the major manufacturers of digital camera media, the number of photos that can be held in memory varies by the resolution of the photo and the capacity of the media. If the inexpensive 32meg memory card is used, at maximum resolution, a 2 megapixel camera will store about 35 images, while only storing 12 images from a 5 megapixel camera. Media of 256megs (often around $50) can hold much more; 284 images at 2 megapixels, and 102 images at 5 megapixels. A chart showing the capacity of different media is available at www.lexarmedia.com/digfilm/index_cf.html. It should also be noted that the memory, also referred to as “digital film”, can be reused indefinitely.
Almost all new digital cameras come with some form of fast USB connectivity to download images to the computer. Accessories such as docking stations, and external card readers are a convenience, but not a necessity.
As an added convenience, most local photo finishers now print photo-grade images directly from the camera memory, at prices lower than printing them yourself. Now we can have the best of both worlds.
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