Arguably the most important weapon in a photographers’ arsenal, lenses are also one of the most variable. From the widest 10mm fish-eye to the longest 800mm telephoto, optics are available in every conceivable size, weight and focal length. Due to the smaller sensors used in many of today’s digital SLRs, however, focal lengths vary depending on the model in question.  But whether you’re a landscaper looking to capture dramatic sunsets or an architectural fanatic looking to isolate fine details, there’s a multitude of options that fall into four categories. Here’s the low-down.

Standard
On full-frame digital SLRs standard lenses fall between 40mm and 55mm, though 50mm is the accepted norm. You’ll need a 35mm lens to get the same field-of-view on digital SLRs with the smaller APS-sized sensor. Closest to the field-of-view of the human eye, standard lenses offer an undistorted perspective and are often used for flattering portraits. Just for the record, the true field-of-view of the human eye is 43mm!

Wide-angle
With shorter focal lengths and wider angles-of-view than standard lenses, wide-angle lenses are employed by landscape and reportage specialists. Remember you’ll need a shorter focal length on many digital SLRs than a 35mm or full-frame digital model. This need for shorter focal lengths on many digital SLRs has produced a raft of new models. A 17-35mm model, such as the one shown below, gives a field-of-view equivalent to 25-52mm on a full-frame SLR.

Macro
If you’ve ever wondered how photographers fill the frame with small subjects such as petals and insects, the answer is the humble macro lens. Allowing for 1:1 (life-size) reproduction and focusing from as close as 2in, true macro lenses are specifically constructed for close-up photography. They are commonly available in focal lengths between 50mm and 180mm.

Telephoto
Any lens that weighs in with a focal length above 50mm is said to be a telephoto lens. Short telephotos (between 70mm and 120mm) are ideal for portraiture, while longer focal lengths (between 135mm and 300mm and above) are perfect for sports and wildlife. Remember, the magnification of a lens on most digital SLRs is increased by around 1.5x, so a 200mm lens is equivalent to a 300mm on a full-frame camera.

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If you travel with your digital camera, you may be worried that airport x-ray machines may damage photographs on your digital camera memory or even the memory cards themselves.

Relax! Though I cannot give a 100% guarantee, everything I have read in books, on the Internet, and in magazines states that these machines do not have an adverse affect on such cards, unlike film.

If you are still concerned, you may want to consider archiving your digital camera photos to compact disks before returning on an airplane. This provides an extra level of backup and should ease your mind.

To ease your concerns, the I3A (International Imaging Industry Association) released a press release on December 15, 2004, regarding tests on digital camera media performed by the imaging industry and United States Transportation Security Administration (TSA). In it, they state that x-ray machines used by the TSA should cause no damage to digital media, whether or not the media is in checked or carry-on bags.

One question that often comes up when printing digital photos – how many megapixels do you need for a certain size print, such as an 8×10 inch print, an 11×14 inch print, or a larger poster size?

Part of this discussion rests on the quality of the image. If an image is slightly blurry, you may need to resample it to a lower number of megapixels to offset the blurriness, else the quality of the full-size printout may be less than expected.

Printout quality depends on the paper and printer as well. Make sure you are using quality photo paper and not just inkjet or laser paper. Plus, ensure that your printer is configured to use the high-quality paper.

The dpi (dots per inch) of a printout helps determine the image quality and how many megapixels you may need. Generally, the greater the dpi, the clearer and cripser the printout (up to a point). While you can print larger images from smaller digital photos by decreasing the dpi, the results may not be as impressive as if the original image were larger and printed with a larger dpi.

To factor how many pixels you need, multiple the dpi by the size of the photo. Thus an 11×14 image at 150 dpi will need 11*150 by 14*150 pixels, or 1,650 by 2,100 pixels (3.465 million pixels).

Now, with this size, you would think that a 3.5 megapixel camera would handle it. Not so fast! One 3.5 megapixel digital camera I found actually had an image resolution of 2144 x 1608. While 2144 is greater than 2100, 1608 is NOT greater than 1650! Thus this digital camera, which SHOULD be able to print 11×14 images at a 150 dpi, can’t muster enough detail. It’s close, but not enough, yet it might be satisfactory for you needs.

Digital camera megapixels and actual resolution (note these can differ depending on the camera):

2 megapixels: 1600 x 1200
3 megapixels: 2048 x 1536
4 megapixels: 2274 x 1704
5 megapixels: 2560 x 1920
6 megapixels: 2816 x 2112 – 3032 x 2008
7 megapixels: 3072 x 2304
8 megapixels: 3264 x 2,468

Pixels needed for a 150 DPI image (fair to good image quality)
———-
8×10: 1,200 X 1,500 pixels – most 2-megapixel cameras

11×14: 1,650 X 2,100 pixels – most 4-megapixel cameras

16×20: 2,400 X 3,000 pixels – most 8-megapixel cameras, maybe some 7-megapixel cameras

Pixels needed for a 200 DPI (good image quality)
———-
8×10: 1,600 X 2,000 pixels – most 4-megapixel cameras, maybe some 3-megapixel cameras

11×14: 2,200 X 2,800 pixels – 7-megapixel cameras, though most 6-megapixels cameras should be close enough

16×20: 3,200 X 4,000 pixels – although this is only 12.8 megapixels, most cameras won’t have the same aspect ratio (width versus height), thus you may need a camera with a greater number of megapixels

Again, these numbers are just provided as the results of mathematical formulas. You can resample the image to some degree to make it larger than normal, play around with the printer dpi, etc., and get acceptable larger prints from smaller photos. Just realize that the image quality may not be optimum, though it may be sufficient for your needs.

Listen. Stuff happens. Computer hard drives die. Digital media might get damaged. Computer viruses and spyware attack. The wrong pictures get deleted. Any of these things can occur, causing you to lose your precious photographs.  When you are done taking photographs with your digital camera, immediately save those photographs to external media!

Don’t let it happen to you.

As soon as you are done backing up your digital camera images to ZIP, CD, or DVD, make sure to label the media! At a minimum, you should write down the date(s) the photos were taken and the main subjects of the photographs. You may also want to label the backups with the name of the camera used to take the photos, and possibly the resolution of the photos. Start a good labeling system now and you’ll make it easier on yourself when you want to go back and use or print a photograph taken several years ago.

There are actually two types of cameras that you can choose.  It all depends on how new you want to be or how traditional you want to remain.  Currently, the choices range from purchasing a manual camera or of the slew of hi-tech digital cameras.  To make it easier for you, the following are tips to help you choose the best digital camera as well as the perfect manual camera for you.

If you want to buy a manual camera, first determine if you would like for photography to be a hobby that is serious or simply a past time.  If you’re really serious, it is best that you choose a camera that is an SLR or specifically a single lens reflex camera.
 
The difference between a SLR camera and an average point & shoot one is that the former allows the photographer to adjust the aperture as well as the camera’s shutter speed. Though the pictures may be a bit difficult to take, it is more fulfilling to do so – if you have the patience for it – it allows you the opportunity to create the pictures you want.

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Anyone who wants to learn how to be a photographer doesn’t have to enroll for many years to get a degree. There are colleges who offer this as one of the subjects which the student may take as an elective. Can you still learn how to be a photographer being out of school for many years? The answer is yes. The only thing needed is your dedication to learn from the proper techniques and a camera to take some shots.

Some students don’t have to go to campus anymore. There are some institutions that offer distance education. A good example is the New York Institute of Photography.

You will learn everything from exposure, lenses, the various techniques used to cover different events, journalism and much more. Being affiliated with the school, you will be entitled to free online magazine articles such as contests and digital imaging.

Classes are composed of 30 lectures on various topics. You will get a brief introduction through each and then can specialize on a particular field of interest. The nice thing about the program is that you don’t have to quit your regular job. This can be done in your free time so there isn’t any pressure in learning everything about photography.

Aside from theoretical lectures, there will be a lot of hands on experience. This will make it easy for you to apply what has been learned as seen in the photographs that have been taken using the camera.

The common notion of being a photographer is that you must have a dark room to develop the photos. You will be happy to know that this isn’t the practice anymore. Some of the best names in the business don’t do this anymore which gives more time to focus on getting the perfect shots.

Education is something you can never get enough of even as you get older. The curriculum is there. All the individual has to do is acquire knowledge from some of the best then apply it after finishing the course.

The rewards of becoming a photographer are endless. It is up to the you whether or not you have the potential to win the Pulitzer Prize or be one of many who do this as a profession.

Photography school can be a lot of fun. You should just submit the requirements then enroll in the course.

Learn Digital Photography  - Is an excellent guide to Digital Photography and finding which camera suits your needs.