Choosing a Digital Camera
Which digital camera should I buy? With the vast and ever-increasing number of cameras on the market today, this can be a rather daunting question. Where is one to start?
Megapixels
Let’s start with the first thing camera manufacturers tout these days: Megapixels. A pixel (picture element) is simply a single point in an image, and a megapixel is one million of these points. Therefor, a camera that records images at 2592 x 1944 pixels would have a resolution of 5,038,848 pixels or 5.0 megapixels.
More is better, right? That seems to be the conventional wisdom regarding the number of pixels. Below is a chart commonly used by photo processing labs as a guideline to print size and the the corresponding megapixel count required for quality results.
Print Size | Min Megapixels |
Min Resolution |
4x6 | 1 |
1280x960 |
5x7 | 2 |
1600x1200 |
8x10 | 3 |
2048x1536 |
11x14 | 5 |
2560x1920 |
16x20 | 6 |
3008x2000 |
Even in the widely used chart above, we can see that a 6mp image is enough for excellent prints up to 16 x 20 inches. I’m not sure about you, but I don’t know many people that make a lot of 16 x 20 prints.
So why are the camera makers pushing their latest and greatest uber-pixel cameras? Simple, to sell more cameras!!
Given that even photo labs admit that 6mp make great large prints, what can real life tell us? David Pouge, tech columnist for the New York Times and host of the Science Channel’s “It’s All Geek to Me” performed an experiment. He had images shot at 13, 8 and 5 mp and had them enlarged to 16 x 24 inch prints. He then ran another experiment using 16.7, 10 and 7 mp images, again enlarged to 16x24 prints. Have you guessed the punchline results yet? Yep – it was almost impossible to tell the differences even when displayed side by side.
(Pogue's tests can be found here)
Another argument for more and more megapixels is that you may want to crop a picture to enlarge a small section of it. Again, the conventional wisdom is not entirely on the money. Kevin has done a nice article here on that subject
So, despite what the manufacturers want you to believe, megapixels are definitely not the most important factor when choosing a digicam. In fact, a camera with 4 megapixels may very well provide better large prints than one with 6 megapixels.
Zoom
Most cameras today offer at least some zoom capability. Most have both optical and digital zoom abilities. The optical zoom function works just like a zoom lens on an old school film camera. The lens increases or decreases magnification of the subject, thereby bringing the shot “closer” or “further” with no actual enlargement of the image. Digital zoom, on the other hand, simply enlarges the image digitally, effectively cropping the photo and introducing noise and pixelation.
(my own examples of zoom photos)
A few years ago, camera makers touted the zoom range as a factor of the optical and digital zoom. In other words, the camera would say “15x ZOOM!” in big bold type on the box. Only by reading the fine print would one learn that it had a 3x optical and a 5x digital zoom range.
My advice? Completely ignore the digital zoom factor. In fact, disable the digital zoom function if your camera allows. You will be much better off cropping and enhancing using low cost or even free photo editing software. I will cover some photo software options in another section soon.
What type of zoom range should you look for? That depends on the type and location of the photography you plan to do the most.
If most your pictures will be taken indoors at close quarters, you really won’t need a lot of zoom range, 3x for example. In that case, you should look for a lens that is fairly wide angled, say the 28 or 32 mm equivalent of a 35mm camera. Under these conditions, a smaller zoom factor of 3x or so should be more than sufficient.
On the other hand, if you do a lot of shooting outdoors, especially sports photography, a longer lens and larger zoom factor can be a picture saver! Excellent cameras with 10x or greater zoom factors (topping out at a 400mm equivalent of 35mm cameras) can be bought for under $200 these days.
Form factor / Camera size
These days, the shape and size of the camera really boil down to personal preference. Generally speaking, the size of the camera has little or no bearing on the quality of the images it can produce. The photos produced by some tiny pocket cameras can be truly stunning, rivaling some high dollar digital SLRs.
A more important factor in picking a form factor is shooting style and ease-of-use characteristics. In general, the smaller point and shoot cameras are just that, super easy to operate pointing and shooting. They are also easy to carry in a purse or even a shirt pocket, making them a great tool for spur of the moment candid photography.
Many of the compact cameras on the market these days have done away with the eye level viewfinder, utilizing the LCD screen as the only means of framing the photographs. This is purely a matter of individual preference as many people use only the screen when snapping pictures, while others usually go for the viewfinder. It should be noted, however, that the LCD screens can sometimes be difficult to see and read in bright sunlight.
The second class of digicam is the SLR-like camera. Although not true single lens reflex cams, they do have a form factor similar to an SLR. Sometimes classified in the “point and shoot” category, they are probably better defined as “pro-sumer” cameras. Most will function very nicely in point and shoot mode, but also offer an array of advanced features such as multiple exposure modes, longer zooms range and eye-level viewfinders.
At the top of the heap, and priced accordingly, are digital SLRs. Aimed at the professional and the advanced amateur photographer, these cameras offer interchangeable lenses, larger image sensors, and loads of accessories.
All things considered, most people will find that the middle of the road prosumer cameras tend to offer the most bang for the buck.
Other Resources
To finish out this overview, I would like to mention a few websites that provide a plethera of research information for the budding digital camera purchaser, mostly in the form of reviews. A few of my favorites, in no particular order are:
Steve’s Digicams
Digital Camera Resource – dcresource.com
Digital Camera Reviews – dpreview.com