Checking photo resolution: Do you have enough pixels?
For good-quality prints, you need an adequate pixel population. The short story is that you should aim for the neighborhood of 300 pixels per linear inch of your print. If you want to print, say, an 11 x 14-inch photo at 300ppi, your image needs to contain at least 3300 x 4200 pixels, or roughly 13.8 megapixels. (Here's the math: 11 inches by 300 equals 3300 pixels; 14 x 300 equals 4200 pixels; and 3300 x 4200 pixels equals a total resolution of 13.8 million pixels, or megapixels.)Without enough pixels, prints will look jagged along curved and diagonal lines and exhibit other visual defects. Even though some photo programs enable you to add pixels to an existing image, doing so never improves picture quality.
If you're printing photos at a retail or online site, the printer's order form usually indicates how large a print you can make given the image's pixel count. If you're doing your own printing, you have to be the resolution cop, though. You can find out how many pixels you have by looking at the image file properties during picture playback on the camera. (You may need to change the camera's display settings to do so.)For example, in the image below, the resolution value reports 4032 x 3024 pixels. (Everything was dimmed except that value to make it easier to spot.)
You can usually choose a playback display mode that indicates the picture resolution.You also can view resolution information in the photo software after you download pictures to your computer. For example, here's how to get to the resolution data in the free photo programs provided on Windows-based and Mac computers:
- Windows: In Windows Photos, click the image thumbnail to display the photo in a window similar to what you see below. Click the three dots labeled Click to open menu to display a drop-down menu. From that menu, choose File Info to see a panel showing data including the filename, the date the picture was taken, the file size, and the picture resolution.
In Windows 10 Photos, you can check the pixel count by viewing the image in the Photos program.Note that the file size value shown here (28.3MB, or megabytes) is not the image resolution, which is stated in megapixels (MP). In this case, the megapixel count is roughly 24.1 MP (4016 x 6016 pixels equals about 24.1 million pixels).
- Mac: After launching Photos, click the image thumbnail, open the Window menu, and choose Info. Or just click the i button highlighted below. You then see a box listing an assortment of picture settings, including the resolution.
In the Mac Photos program, click the i button to display resolution data.
Getting print and monitor colors in sync for quality photos
Aside from poor picture quality, the number-one printing complaint is that colors on the computer monitor don't match the ones that show up in print. When this problem occurs, most people assume that the printer is to blame, but in fact the most likely culprit is the monitor. If the monitor isn’t accurately calibrated, the colors it displays aren’t a true reflection of your image colors.You can start with a software-based calibration utility, which is built into your Windows or Mac operating system. The program guides you through the process of adjusting the monitor by displaying various color swatches and other graphics and asking you to provide feedback about what you see on the screen.
Both the Windows and Mac operating systems offer built-in calibration programs. If you use a Mac, the utility is called Display Calibrator Assistant. Windows 10 offers a similar tool named Display Color Calibration.
For a more accurate calibration, you may want to invest in a device known as a colorimeter, which you attach to or hang on your monitor, to accurately measure and calibrate the display.
If your monitor is calibrated, color-matching problems may be caused by these other issues:
- One of the print nozzles or heads is empty or clogged. Check the manual to find out how to perform the necessary maintenance to keep the nozzles or print heads in good shape.
- You chose the wrong paper setting in your printer software. When you set up the print job, be sure to select the correct paper-type — glossy, matte, and so on. This setting affects how the printer lays down ink on the paper.
Some paper manufacturers provide ICC profiles, which are small data files that help your printer and computer better translate your image colors to the specific paper you're using. (ICC stands for International Color Consortium, the group that developed the universal color translator on which this system is based.) After you download and install the profiles, you should see the related paper types (for example, Epson Premium Luster) in the list of options in your printer settings dialog box. If you're using paper made by the printer manufacturer, though, the profiles are usually automatically added when you install the printer software during initial setup.
- Your printer and photo software are fighting over color-management duties. Some photo programs offer features that enable the user to control how colors are handled as an image passes from camera to monitor to printer. Most printer software also offers color-management features. The problem is, if you enable color-management controls in both your photo software and your printer software, you can create conflicts that lead to wacky colors.
Even if all the aforementioned issues are resolved, however, don’t expect perfect color matching between printer and monitor. Printers simply can’t reproduce the entire spectrum of colors that a monitor can display. In addition, monitor colors always appear brighter because they are, after all, generated with light.
It’s not a good idea to use a laptop monitor or tablet to evaluate images because the displayed colors, brightness, and sharpness can change when you adjust the screen angle or even move your head a little. It’s a good idea to buy a separate monitor that you can connect to your laptop when you need to work on your images.Finally, be sure to evaluate print colors and monitor colors in the same ambient light — daylight, office light, whatever — because that light source has its own influence on the colors you see. If your prints will be displayed in a gallery, you also should make sure that colors look good in whatever lighting the gallery uses. Ditto for prints you hang in your own home, of course.