Dpi Picture' title='300 Dpi Picture' />All About Digital Photos The Myth of DPI. Many people seem to get hung up on the DPI dots per inch or PPI pixels per inch setting within a digital photo as a measure of the quality of those photos. To set the record straight, the DPIPPI setting within a digital photo has NOTHING to do with digital image quality The resolution of a digital image is its pixels usually expressed as megapixels. The PPI of a paper print IS a measure of quality of the paper print, not of the digital photo but it has nothing in real world terms to do with the DPIPPI setting within the photo. Sims 3 Rebel Hangout on this page. What Is 300 DpiConfused Read on. Note, this page is mostly about the DPIPPI setting within a digital photo the setting that can be changed by photo software. For an explanation of what DPI and PPI actually are it is best to read the What is DPI page first. If youve read the sections titled What is a Digital Photo and What is a High Resolution Photo youll know that there are four main factors that determine image quality 1 The size in pixels of the digital image. Dpi To 300 Dpi Software Download' title='72 Dpi To 300 Dpi Software Download' />300 Dpi CamerasThe quality of the recording device cameras optics and sensor, scanners sensor. The digital format it is stored in lossless vs lossy compression. The technical proficiency and the eye of the photographer. Several other factors also come into play, but the above are the main factors that determine the overall quality of the original digital photo. The size of a digital photo is measured in pixels the smallest colour component in a photo. The two photos above are exactly the same size, 3. JPEG quality of 7. Even though their DPI has been set to radically different values, the photos are identical in quality the pixels dont change. So, what is DPI and why are so many people hung up about it DPI is short for Dots Per Inch and it actually refers to printer dots per inch. These days, when used in photo software, it means PPI, which are pixels per inch. DPI and PPI are two different things, yet often DPI is used when PPI is meant, so read its usage in context. Not sure if this has been asked. A newspaper wants to print a photo of mine. They want it in 300 dpi. However, I took the photo at 72 dpi. Can I covert it to 300 dpi. I purchased a stock photo and its size was 72 dpi. Is it safe to change a file from 72 dpi to 300 dpi What should I be concerned with when I do thisThis author shows an example of how 72 DPI and 300 DPI look when printed. And guess what, the 72 DPI image looks bigger. Jive Software Version. PPI is a measure of how a image is printed to a medium such as paper. Many software programs call PPI a measure of resolution which leads to more confusion since it is the resolution of the printed output, not the resolution of the digital image see Adobe Photoshop Image Size Dialog Box for an example of this. If the pixels of an image do not change, then it has the same digital resolution no matter what number is parked in the DPIPPI setting of the photo. One factor in the quality of printing to paper is many pixels per inch are delivered to the printer, a number between 2. But that quality, the PPI, is determined by how many pixels the image has not the number parked in the DPIPPI setting section. Part of the confusion and the myth is generated by the fact that the PPI setting can and is by some used to determine the print size on virtual paper. Its often how graphic artists use photo programs, to virtually print size the photo. This has led to the erroneous view that this setting controls the resolution of the digital photo itself. But a digital photos resolution are its pixels and if those dont change, the photo remains the same resolution. The DPIPPI number in the photo is simply a convenient at times conversion factor. Printing on all of todays home printers and most modern commercial printers involves remapping the photo, converting the pixels of the photo into printed dots. This isnt done on a one to one basis, one pixel does not equal one printer dot. In illustration of digital resolution, with the two photos shown above, each 3. If they were both printed to 6 inch paper, they would both be printing at 5. The printer itself may be using 1,4. With the printed output, you would not be able to tell which one was set at 1. So, when someone asks you for a dpi photo, they really mean a digital image of sufficient pixel dimensions to be able to meet their required pixels per inch requirement usually 3. For a more extended discussion of this see What Print Shops Really Want. It doesnt matter what number is parked in the DPIPPI setting of the photo what counts is that there are enough pixels in the digital photo to meet their minimum PPI requirement. Of note, camera manufacturers such as Canon have it right, they properly refer to digital resolution as the pixel dimensions of the photo. DPIPPI Another Definition. For some, it is easier to think of the DPIPPI of a digital photo simply as a conversion factor that some software uses to set the paper output dimensions. This is basically all it is it is a 5 byte very tiny string in the header of a digital photo file. Its not actually part of the image, it does nothing within the photo file it doesnt change the digital photo in any way, but some software will use it to set the paper output dimensions in inches or centimetres. Some software will also unfortunately use it to re sample an image see The Horrible DPI Mistake below. My general advice is to never change the DPI unless some silly photo shop graphics designer asks for it to be changed then change it using my Change DPI instructions. When printing with a program such as Photoshop that uses the DPI to set paper output, print using the Print with Preview option, using the Scale to fit media selection to scale the photo to the print size you desire without changing the DPI. Flatout 2 Game Setup. Player Condensed Bold. If you must resize a photo, dont use DPI to do it, change the pixels see the Change Size section. The Horrible DPI Mistake. Heres the scenario a print shopgraphics designermagazine asks a client for a photo at 3. They wish to print it out at 5 x 7. The client already has a beautiful digital photo with pixel dimensions of 2. The client notices that the photo editing software is showing that the photo is set to 7. So, following orders, the client types in 3. In doing so the image is resampled and is enlarged over 4 times to pixel dimensions of 8. The client sends this enlarged 3. The print shopgraphics designermagazine reject it too grainy, too colour blotched. The client is crushed. The sad thing is that the client already had the perfect photo 2. PPI. The print shopgraphics designermagazine didnt know what they really wanted see What Print Shops Really Want and the client didnt know how to change the DPI without resizing the image to give the print shop what they mistakenly think they need see how to change the DPI. So why should I care about DPI Well, if you are using an older photo program it may use DPI to set the the size of the printed output. With these programs youll have to adjust the DPI in order to adjust the size of the printed output. This is becoming a thing of the past since most newer photo programs simply allow you to set a size output i. DPI setting. Programs that use DPI to set the size of printed output are in fact using PPI, they arent telling the printer how many dots per inch to print DPI, rather they are sending the printer x number of pixels per inch which the printer may well print at a much higher DPI. Some programs such as Word Processors and Desk Top Publishing programs will use the DPI of an image to set the default size of the image. For example, a 1. All modern programs allow you to easily visually resize such an image, but it can be convenient to set the DPI of images you plan to use in such programs to the DPI that will match the approximate paper size that you intend for that image. So it you have a 2.