How many Megapixels does it take to create a great digital image? A decade or more ago, top end digital cameras were 3 Megapixels and not more. Quickly times have changed and even a freebie cell phone can take images of 10 Megapixels or more. So how many megapixels do you need for your next digital camera?
Understanding what a pixel is can help you make sense of the bigger picture (no pun intended!). A pixel is a short for a "picture element". it is a single 'dot' of image information. Pixels sit in a rectangular or square matrix that when multipled together tells you the total pixels contained in that piece of digital information. For example, if you had a three rows of three blue dots, like a tic-tac-toe board, each representing a pixel, the total size of that "image" would be 9 pixels.
If you took your tic tac toe box and made it 10 rows by 10 columns (instead of 3 x 3), then you'd have a 1000 pixel image. Likewise, 1000 rows & 1000 columns equals a million pixels, or one megapixel. You can see how image size can quickly grow by simply adding more rows and columns of information.
So what kind of image can you make with a million pixels? It depends how you produce the image. If the image will be displayed on a computer screen, the resolution of your computer screen will determine how large the image is. Suppose you have a photo a friend sent you that is 320px x 240px large. If your computer screen is set at 800px x 600 px (a common size) that image will fully appear on your computer screen without having to scroll around. An image size of 320 x 240px or 600px x 400px are nice sizes for viewing on a computer or webpage.
Now consider taking that great snapshot from your facebook page and printing it on your fancy photo printer. A minimum resolution of 200dpi (dots or pixels per inch) is considered necessary for good quality photos. That 320 x 200 px image now prints out at only 1.6" x 1" on your glossy photo paper. To get a better quality image, you'll need a larger sized image.
Let's cut to the chase. What image size in pixels do you need to print out an nice looking 8 x 10 photo from your photoprinter on glossy paper? 8" multiplied by 200 dots per inch (pixels per inch) is 1600 pixels. Do the same for the 10" x 200 and you get 2000 pixels. 2000 x 1600 pixels equals 3.2 million, or 3.2 Megapixels. Here's where you should stop and scratch your head. Read the above paragraph againan 8 x 10" image can be printed from photo that's only 3.2 Megapixels. Most people would be happy with a glossy 8 x10 of their favorite camera photos. Then why do we see cameras with sensors of 10, 12 & 14 megapixels?
One answer is that hardly any of us are happy with the initial snapshot we typically take. It's common to zoom, crop, rotate and otherwise manipulate your digital image after the photo is captured. Therefore the more detail you can record at the time the image is taken, the more manipulation you can do and still have a nice looking printed image at the end of it all. But do we really need camera phone apps that can take 10MP images? Consider that limited edition professional prints of up to 13x 19" are sold at the natural history museum for $650and were taken with a 6MP Nikon Digital Camera. (source: Ken Rockwell dot com)
So as you shop for your next digital camera, don't get too carried away by looking for the most megapixels you can purchase. Look instead for just enough (6MP should be plenty), and spend your money on other components that create a quality camera such as the lens elements and any other exposure features that are important to you.
Understanding what a pixel is can help you make sense of the bigger picture (no pun intended!). A pixel is a short for a "picture element". it is a single 'dot' of image information. Pixels sit in a rectangular or square matrix that when multipled together tells you the total pixels contained in that piece of digital information. For example, if you had a three rows of three blue dots, like a tic-tac-toe board, each representing a pixel, the total size of that "image" would be 9 pixels.
If you took your tic tac toe box and made it 10 rows by 10 columns (instead of 3 x 3), then you'd have a 1000 pixel image. Likewise, 1000 rows & 1000 columns equals a million pixels, or one megapixel. You can see how image size can quickly grow by simply adding more rows and columns of information.
So what kind of image can you make with a million pixels? It depends how you produce the image. If the image will be displayed on a computer screen, the resolution of your computer screen will determine how large the image is. Suppose you have a photo a friend sent you that is 320px x 240px large. If your computer screen is set at 800px x 600 px (a common size) that image will fully appear on your computer screen without having to scroll around. An image size of 320 x 240px or 600px x 400px are nice sizes for viewing on a computer or webpage.
Now consider taking that great snapshot from your facebook page and printing it on your fancy photo printer. A minimum resolution of 200dpi (dots or pixels per inch) is considered necessary for good quality photos. That 320 x 200 px image now prints out at only 1.6" x 1" on your glossy photo paper. To get a better quality image, you'll need a larger sized image.
Let's cut to the chase. What image size in pixels do you need to print out an nice looking 8 x 10 photo from your photoprinter on glossy paper? 8" multiplied by 200 dots per inch (pixels per inch) is 1600 pixels. Do the same for the 10" x 200 and you get 2000 pixels. 2000 x 1600 pixels equals 3.2 million, or 3.2 Megapixels. Here's where you should stop and scratch your head. Read the above paragraph againan 8 x 10" image can be printed from photo that's only 3.2 Megapixels. Most people would be happy with a glossy 8 x10 of their favorite camera photos. Then why do we see cameras with sensors of 10, 12 & 14 megapixels?
One answer is that hardly any of us are happy with the initial snapshot we typically take. It's common to zoom, crop, rotate and otherwise manipulate your digital image after the photo is captured. Therefore the more detail you can record at the time the image is taken, the more manipulation you can do and still have a nice looking printed image at the end of it all. But do we really need camera phone apps that can take 10MP images? Consider that limited edition professional prints of up to 13x 19" are sold at the natural history museum for $650and were taken with a 6MP Nikon Digital Camera. (source: Ken Rockwell dot com)
So as you shop for your next digital camera, don't get too carried away by looking for the most megapixels you can purchase. Look instead for just enough (6MP should be plenty), and spend your money on other components that create a quality camera such as the lens elements and any other exposure features that are important to you.
About the Author:
Before buying your next pocket digital camera, read Adrian's reviews on Olympus XZ 1 Review and find out why the neat little Olympus XZ 1 should have a place in your photo bag.. This article, Megapixel Overload - How Many is Enough For Your Next Digital Camera? is available for free reprint.
No comments:
Post a Comment