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Frequently Asked Questions
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"It is better to know some of the Questions than all of the Answers."
~ James Thurber ~
Why isn't my photo centered on the paper?
What pixels per inch should I use when I print?
Why do the colors on my print look different than on my computer screen?
Which inkjet printer should I buy?
Why do my inkjet prints have white streaks?
Why won't my inkjet prints dry?
Most imaging applications center the image in the printable area on the paper. (See printable area and paper feed on the Definitions page in the Tutorial.) Most inkjet printers have a trailing-edge margin that is larger than the leading-edge margin, which means that the printable area is not centered on the paper. If your printer can print to the edge of the paper, or if your printer driver has a built-in setting to center the image on the paper, please read the user manual to determine how to set up your printer properly. If your printer lacks these options, use the following procedure to center the photos on the paper:
- Print a test image on plain paper and measure the margins for your printer.
- Calculate the Offset.
- Use your imaging program to add a white top border (for portrait orientation) or left border (for landscape orientation) to your digital photos. N.B. This assumes that your printer's landscape orientation is set so that the left edge of your photo is the first part of the photo printed. Some printer drivers allow either the left or right edge to be the first part printed.
Step 1: Download this file: print-area-letter.jpg. Open it in your imaging application and print it on a sheet 8.5 x 11 paper in portrait orientation. Turn off any 'fit to paper' features. Ignore any warnings about the file being too large for the paper. It is too large. The objective is to print an image that is large enough that it will be 'clipped' by the printer driver so as to show the edges of the printable area on the paper. Measure and record the width of the unprinted top and bottom margins using the illustration as a guide.
Step 2: Calculate and record the Offset – twice the distance that the image must be moved to center it on the paper.
Offset = Bottom Margin - Top Margin
Step 3: Note: these instructions show the procedure for Adobe® PhotoShop Elements. Other imaging applications have similar capabilities. This procedure adds a white margin to the top or the left side of the image by changing the 'canvas' size.
For a portrait orientation image:
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| 1) Open the image. | 2) Be sure that the background color is set to white on the toolbar. 3) Select Image>Resize>Canvas. |
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| 4) Add the Offset from Step 2 to the Height measurement and type that new value in the Height box. 5) Select the center box in the bottom row of the Anchor. |
6) The resulting image will have a white margin on the top that is the width of the offset. 7) Save this image, set your printer driver to center the image in the printable area, and print. |
For a landscape orientation image:
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| 1) Open the image. | 2) Be sure that the background color is set to white on the toolbar. 3) Select Image>Resize>Canvas. |
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| 4) Add the Offset from Step 2 to the Width measurement and type that new value in the Width box. 5) Select the center box in the right hand column of the Anchor. |
6) The resulting image will have a white margin on the left side that is the width of the offset. 7) Save this image, set your printer driver to center the image in the printable area, and print. |
There are firmly held and widely varying opinions on what number of pixels per inch is required to make a good quality inkjet print. While we cannot hope to settle the issue, here are a few things to consider:
(1) One rule-of-thumb for medium-resolution printers is to divide the dpi of the printer by 4 to estimate a good value for the best ppi to use for printing. For example, for a 1440x720 dpi printer, use 360 ppi. The printer needs to be able to place many drops of ink to simulate the colors of the pixels. Sending a 360 ppi digital photo to a 1440x720 dpi printer means that the printer has 8 drop positions with 4 or 6 colors of ink to simulate each pixel's color.
(2) What can you see with a typical pair of human eyes? In the photo industry, photographic quality is often defined as 300 ppi, continuous tone, 24-bit color. Continuous tone, or 'contone', means that each pixel on the print is a square patch of a single color. 24-bit color means that there are about 16.8 million available colors for the squares. 300 ppi means that there are 90,000 pixels in each square inch. Dye sublimation printers and the high-end digital photo printers used by photo processing labs are continuous tone printers. Although inkjet printers are not continuous tone, with newer, high resolution printers, the 300 ppi value is becoming a useful benchmark.
(3) The usable pixels per inch will depend on the paper. If you are printing on plain paper or uncoated watercolor paper, which have large dot sizes, you can usually use a lower ppi than if you are printing on 'high resolution' matte or photo paper. Images on uncoated papers will look 'softer' – or slightly fuzzy – because of the large dot size, and there isn't much point in sending lots of pixels to your printer that won't show on the final print.
(4) If you are using high resolution matte or photo paper, a ppi value between 240 and 360, should yield pleasing results. You will need to experiment a bit to determine your own preferences.
1) The image on your computer screen is composed of red, green, and blue light generated by the monitor. On the other hand, when you look at a printed image, whatever light is available in the room is reflected or absorbed by the paper and the colorants on the surface of the print. The perceived color is affected by the color or 'color temperature' of the ambient light and how the particular colorants may change appearance when the ambient light changes (metamerism).
2) Calibration: most people are not using calibrated computer monitors nor are they using special calibration profiles (ICC Profiles) for their printers. It is not possible to match colors if the monitor and printer are not calibrated.
Does it matter?
It depends...
Most people are only interested in 'good enough' color. Having a pleasing printed image is often more important than whether the print actually matches the monitor. There are very few times when someone might actually look at the print and the monitor at the same time, so matching might not be all that important.
For other people, critical color matching is extremely important. In that case, it is absolutely necessary to have a calibrated 'workflow' including calibrating the monitor, printer, etc. and understanding how to apply color calibration while editing and printing digital photos.
There are several companies who provide software and hardware for color calibration. A few of them are listed in the Color section of the Digital Photo Info page. There are also links to tutorials on color and color management listed in that section.
If your inkjet prints develop a pattern of white streaks, which run across the paper, the first thing to do is run a nozzle check on plain paper. Your printer manual will explain how to run a nozzle check, and how to diagnose clogged nozzles. If you have clogged nozzles, run a nozzle cleaning cycle according to your printer manual's instructions. Be sure to run another nozzle check afterwards. If there are still clogged nozzles, you may run another cleaning cycle.
If you have checked your printer's nozzles, they are all fine, and you are still getting white streaks when you print, check your printer driver settings. Be sure that you have specified the same paper type in the settings as you are using. Printing on photo paper using plain paper printer driver settings can sometimes cause streaking.
Tip: If you have not used your printer for a week or more, run a nozzle check on plain paper before you print on photo paper. Your nozzles may be fine, but if you have a clog, it is better to find out and run a cleaning cycle before you print. It will avoid wasting expensive paper and ink.
It is important to use papers that are compatible with the inks in your printer. In general, matte papers work well on a wide variety of printers. However, glossy papers are less forgiving. If you use HP glossy paper in an Epson printer, or vice versa, you will not get good results.
Even if you are using the same brand of glossy paper as your printer, check the package to make sure that paper is designed to work with your printer model. Over time, printer manufacturers change their inks and papers, so that paper designed to work with new inks may not work with the inks in older printers.
If you are using a glossy paper designed for your printer and you are still getting puddling, check the printer driver settings. Be sure that you have chosen the correct paper type.
Glossy papers made by "third parties", for example Kodak or Hammermill, need special attention. There is usually a tip sheet included in the package (or on the company's web site) that recommend printer driver settings for your printer. Using the recommended settings will generally give you the best results.
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