Good Photographs need lighting

Much of shooting a good photograph comes down to composition and lighting, but what about the hardware?  Most “consumer” cameras can take good photos in the right artistic hands, but just don’t have interchangable lenses.  Upgrading to SLR cameras allows the photographer to interchange lenses, giving the photographer a wider artistic pallette, but which ones to choose?  If you’re not a professional, then you can’t spend thousands of dollars on a good lens. 

First, you should know the criteria for choosing a lens. Some of the criteria are subjective like…Is this lens appropriate for your purpose? Is it versatile enough? Do you like the look and feel of the lens? You should also consider more measurable criteria:

  1. Lens sharpness
  2. Lens speed (F/2.8 is a faster lens than F/5.6 and faster is usually better)
  3. Minimum focus distance
  4. Number and type of lens elements
  5. Manufacture for film, digital, or both (Lenses made specifically for digital cameras will often not work properly on film cameras)
  6. Amount of lens flare
  7. Amount of chromatic aberration
  8. Light fall off (Corner to corner illumination)
  9. Lens weight
  10. Lens construction and build standards
  11. Lens focus speed
  12. Stabilization
  13. Ergonomics
  14. Price
The lens element quality is critical to lens performance. I try to use only lenses with low dispersion glass. These typically eliminate chromatic aberrations that can denigrate image contrast and sharpness.Digital lenses don’t work on film cameras and don’t even work on all digital cameras. Make sure the lens you are buying will work on your cameras. Some lenses will ONLY work with digital cameras featuring an APS sized sensor. On film cameras, these lenses are effectively worthless. Likewise, they don’t work on full frame digital single lens reflex cameras. So if you shoot both digital and film, stay away from special digital lenses.
When testing lenses, know that today’s glass is far superior to anything that could be bought 30 years ago at any price.  Same thing goes for digital cameras:  in 1998, a 6-megapixel SLR camera cost $20,000, but now can be had for less than $1,000.  The cheapest consumer lenses are better than lenses from a few years ago.  The quality may be close to professional gear, but more expensive equipment is usually more durable.  For example, a Nikon D100 is more expensive and has less features than a newer D70 or D50, but has a metal body instead of polycarbonate.
Try to examine the above criteria before making your lens choice and you will be armed with the best information when picking your lens.  Some decent zoom lenses can be had for $150-200 and can rival professional equipment.
Alan is a web architect, stand-up comedian, and your friendly neighborhood Grammar Nazi. You can stalk him on the Interwebs via Google+, Facebook and follow his ass on Twitter @ocmodshop.