Getting Started Scanning - Printing Digital Photos and Scans. Part 3: Printing Digital Photos & Scans The information here pertains to both color and grayscale images that will be printed on an inkjet printer. It does not apply to printing line art images. For more discussion on printing line art images see Scanning Line Art by Desktop Publishing Guide Jacci Howard Bear. (Continued below...) PPI vs. DPI The first important point to understand is the differences between PPI (pixels per inch) and DPI (dots per inch). Pixel Resolution Digital photos and scans are all bitmap graphic types, no matter what format the image is saved to. What this means in relation to printing is that these types of images are resolution-dependent.
Inkjet Printer DPI Today's inkjet printers have three standard output settings: You might also have a draft or economy setting, but you should never use this setting for printing images. A popular myth is that it's necessary to scan an image at the same resolution that you will be using to print. Why is my scan so HUGE? Image Size Calculator/Convertor.
What is a pixel? What is DPI? (Dots Per Inch) You may think you don't know what a pixel is, but, If you've ever seen a card stunt at a sports event, you probably do! A pixel is simply the individual point of color on a digital image. A pixel doesn't have a particular size. It is an abstract represention of a specific coordinate, like a point on a map. This same concept extends to many other digital products. Pixel indicates only a point on a grid, not the size of the point. For Printers and scanners, the individual points of color are often called 'dots' rather than pixels, but the concept remains the same as the stadium. The scanner performs this function in reverse, by recognizing the color at a specific row and column on the item being scanned. Megapixel Calculator - digital camera resolution | web.forret.co. Pixel converter. What is a pixel?
What is DPI? (Dots Per Inch) You may think you don't know what a pixel is, but, If you've ever seen a card stunt at a sports event, you probably do! A pixel is simply the individual point of color on a digital image. This same concept extends to many other digital products. Pixel indicates only a point on a grid, not the size of the point. For Printers and scanners, the individual points of color are often called 'dots' rather than pixels, but the concept remains the same as the stadium. The scanner performs this function in reverse, by recognizing the color at a specific row and column on the item being scanned. Resolution, Resizing, and Dots per Inch - Pathfinder's Photograp. Pixels are the smallest individual unit of a digital image. Each digital camera creates an image with a specific number of horizontal and vertical pixels in a 2 dimensional array.
My Canon 5D, at ISO 200, generates a jpg that is 4368 pixels wide and 2912 pixels tall. That is not pixels per inch, but the actual number of pixels in the horizontal and vertical dimensions. 4368 x 2912 = 12, 719, 616 total pixels - Canon lists the 5D as having 12.7 Mega Pixels - That is precisely what my calculations confirm. The Image>Image Size command in PhotoShop brings up a dialogue box, as seen to the right, that lists this as a 36.4 Megabyte image, and shows that there are 2912 pixels horizontally and 4368 vertically for a shot in a portrait orientation. The box is obtained by pressing Image>Image Size after having opened an image in Photshop. The Image>Image Size command opens the dialogue box to the right, which shows an image size of 40.444 by 60.667 inches, at 72 pixels per inch.