Do digital cameras with more megapixels allow for higher resolution images?
Thanks to digital cameras and cellphones with camera, we now all think we are photographers. There is a relationship between the the megapixels in your photo file and the photo's resolution. However, more megapixels does not necessarily mean a sharper picture.
Image Resolution
Image resolution refers to the number of pixels within an image, and thus the amount of detail an image can contain. This to some degree determines the maximum print size while still maintaining high quality.
Megapixels
One pixel is the single smallest point in a digital image. Think of it as the little boxes that used to make up the characters on your Super Nintendo, except much smaller. A megapixel is made up of 1 million pixels.
Relationship
A 3.2 MP camera phone can record a maximum image size of 2048 x 1536 pixels. The maximum image size from a 10 MP camera is 3648 x 2736 pixels. The number of megapixels directly relates to the image resolution, or level of detail, and thus the maximum size at which you can print a high-quality image. Megapixels are determined by the number of horizontal pixels multiplied by the number of vertical pixels.
The Myth
Some experts claim that the number of megapixels does not always result in a visible difference in image quality when printed. For one thing, there is a point at which your eyes cannot distinguish greater resolution. Photographer Ken Rockwell claims that, "Sharpness depends more on your photographic skill than the number of megapixels." New York Times blogger David Pogue tested this claim by printing photographs taken with 5 MP, 8 MP and 13 MP cameras and displaying them on a wall in Times Square. Only one person, a photography professor, was able tell the three apart and rank them correctly.
The Fact
Resolution, or the level of image detail, relates directly to the potential size of a printed image (assuming the camera was in focus and was kept perfectly still when taking the photo). But while resolution is related to the number of megapixels a camera is capable of capturing, there is a practical limit to how much of that improved resolution we can see with the naked eye. So, Ken Rockwell has a point: Sharpness does depend more on your photographic skill.
