How big is the image displayed on my screen. You can't change a 480 x 640 pixel image to 2000x3000 and expect a great 8x10 print. You can trick a printer by forcing or adding more pixels (called up scaling), but the image will still print as if it was a low resolution image. When you do change the inches or dpi, the numbers usually adjust to keep the same pixel value, but you can force the image and overwrite the other two values - doing so can damage your quality. Some programs let you change image detail like size, dpi, and pixels. See a different image size can still be the same photo size in pixels and in file size. You can change the inches and dpi and keep same resolution in pixels. If printing this image on an ink jet you can easily get away with 240 dpi which will print your image at 40 = 5' x 7.5' Well, just divide the pixels you have by 300 dpi. What print size is the optimum resolution. Lets stick with the same samples numbers I used above. Ok - finally the mathematical explanation on how all the terms relate to each other. the width of the image still has 1800 pixels. Instead of having a 6' image at 300dpi you might have (1800 px / 72dpi) = 25 inches on your screen. When the scanner exports the image it may convert it to 72dpi - doing so did not degrade it because now the image size is greater. Ie: You scanned a 4圆 print at 300dpi which gives you 300dpi x 6' wide = 1800 pixels. What matters, and the number that doesn't change, is the pixel count. *Note on scanners: Some high end scanners will not export the image at the dpi a photo was scanned, but export the image at 72 ppi. In the end your 8x12 image will be printed at 300 dpi. If you want to double the size and print it at 8x12, you must double the dpi to 600 dpi. To reproduce a 4圆 picture you must scan it at 300 dpi to print it out at the same size. Scan Resolution: This is basically the dpi setting on a scanner when scanning a print or negative to make a digital image. A 1mb JPG file should get you a decent 4圆 photo. Only time the file size could be misleading is if the image was compressed into a 2mb file. Usually A 5mb JPG should get you an 8x10 print because I expect it to have 2400px x 3000px.

You can get an idea of how large you can print an image by looking at the file size. A low res image can be 50kb and a large image can be a 15mb file. Ie: 2000px x 3000px = 6,000,000 pixels = 6MP camera sensor chip.įile Size: This is how much space (bytes) an image takes up on the hard drive. Anyway megapixels describes how large an image is by multiplying the height and width of it's pixels. You can have a 5MP camera take better photos than a 12MP camera. It's all about capturing light - some cameras don't do so well in low light situations. Camera producers make it seem like the more megapixels a camera has that it's better quality - that is false. Megapixel: This is how cameras are described. Dividing the pixels by dpi gets you how large an image can print. This is important to know mainly when printing. Image Size: This is the dimension of an image - usually measured in inches. In the end the higher resolution image will just have more pixels.

High resolution can mean more pixels crammed into less space - for example 72 dots per inch vs 300 dots per inch. Resolution: Usually refers to pixels, but mainly describes how much detail an image has and how large it can be printed or magnified before it starts to pixelate. PPI: Pixels per inch is used for computer monitors and other devices with screens. Out of all printer types ink jet printers are more forgiving and can print a great image at 240 dpi. Most printers optimum quality is 300 dpi even if they don't use dots. The standard is 300 dpi for most ink jet printers. See the header graphic above.ĭPI: Dots per inch usually referred to how many dots a printer plots in a inch.

An image is created with millions of these tiny squares. Here is a list of terms and what part of an image they refer to. Everything depends on pixels, pixels, and pixels. I'll show you some simple math, but I must explain some details. Having only a couple numbers of any of the above you can calculate or estimate all the other information. What's the difference between pixels and resolution? It's kind of the same thing - they are all related to each other. Pixels vs DPI vs PPI vs Resolution vs Image Size vs Megapixles vs File Size vs Scan Resolution It's even used when describing sharpness and image detail. When asking what resolution something is the answer can be given in many ways, such as in pixels, dpi, or megapixels. People use the term 'resolution' loosely.

300 dpi resolution calculator