How much resolution do we really need?
Today, we seem to be obsessed with resolution. Every once in awhile newer cameras appear on the market and it seems their main selling point is that their resolution is higher than yesterday's cameras. From hundreds of thousands of pixels to megapixel cameras at over 2 million pixels.
Some cameras even use image enhancement technology to increase the resolution of the camera (a very deceptive and highly questionable practice!). In all this mania for higher resolution we must stop for a moment and ask at least one question, how much resolution do we really need?
Rightfully so, more resolution means more digital information that can be carried in the image. It is the pixels that carry the image and more pixels equals more information or detail. Therefore, the higher the resolution the more pixels in the file. The more pixels, the more information. Therefore, having more resolution is a good thing, no?
But you should first look at the resolution requirements of the output you plan to use and trace the resolution requirements back up to the camera. Are we talking about an 8" x 10" dye sublimation printer? What do we need for maximum resolution for this device to produce acceptable results. No, not excess resolution that we can throw away but just enough to drive the printer and produce the most perfect print possible. Check the specifications of the printer you plan to use and that will be the input requirements for your digital camera. Going beyond this requirement will only mean the printer will have to throw pixels away reducing them in numbers to the maximum resolution of the output device.
Do we want web graphics? How big, in pixels, do we want the picture on our web page? Now look at a digital camera design that will produce this and not much more. Web graphics are quite low in resolution and that opens up a wide selection of cameras. All higher resolution cameras can be used and you can crop or reduce the image resolution to the required size. With higher resolution cameras, you will have to crop or reduce the image or else the graphic files will be too large and take too long to download. Many cameras today will provide too much resolution for web graphics.
Print? Determining the resolution requirements for print is probably the most difficult. There is a wide range of requirements for print from simple pictures of cars and houses for newspaper ads all the way to the highest quality color printing on coated paper. Consider the traditional 2:1 rule where your resolution is roughly twice the intended halftone ruling. You must then consider the size you want the graphic printed. Small photos for newspaper ads or full page photos for high quality color printing. These answers, the size of the picture and the halftone screen, will tell you the resolution your image must be from the camera in order to be adequately converted into halftones and printed on a press. Your camera should be able to support about the largest print and the highest halftone ruling you might ever use. If your resolution is too low, the actual pixels will show. There will also be a lack of image detail.
In any case, we should select camera systems that will yield the required amount of resolution for our desired output system and maybe a little more for growing room. Chasing the resolution of film will only put us into a position where we will then have to develop technologies to throw away digital resolution in order to satisfy the lower requirements of our output devices. How many of us have or will pay for expensive resolution only to throw it away?
Maybe someday we will have "web" digital cameras or "inkjet" cameras that produce only the amount of resolution the printer requires. Commercial photographers who send their pictures to press will have their own requirements as will digital artists or photo journalists. Even consumers will be able to plug into some form of digital technology to save their precious memories of life. Most important of all, we should be able to tell the difference between a consumer camera or a web camera and not be mislead into an expensive mistake. As we move toward this world we should learn to look forward and not let the past technologies wrongly influence our direction.
