Whether you are printing an image to your desktop printer or sending it to a prepress facility, knowing a few basics about printing makes the print job go more smoothly and helps ensure that the finished image appears as intended.
Types of printing
For many Photoshop users, printing a file means sending the image to an inkjet printer. Photoshop can send your image to a variety of devices to be printed directly onto paper or converted to a positive or negative image on film. In the latter case, you can use the film to create a master plate for printing by a mechanical press.
Types of images
The simplest images, such as line art, use only one color in one level of gray. A more complex image, such as a photograph, has varying color tones. This type of image is known as a continuous-tone image.
Artwork intended for commercial reproduction and containing more than one color must be printed on separate master plates, one for each color. This process, called color separation, generally calls for the use of cyan, magenta, yellow, and black (CMYK) inks. In Photoshop, you can adjust how the various plates are generated.
Quality of detail
The detail in a printed image depends on image resolution (pixels per inch) and printer resolution (dots per inch). Most PostScript laser printers have a resolution of 600 dpi, while PostScript imagesetters have a resolution of 1200 dpi or higher. Inkjet printers produce a microscopic spray of ink, not actual dots, resulting in an approximate resolution of 300 to 720 dpi.
About desktop printing
Unless you work in a commercial printing company or service bureau, you probably print images to a desktop printer, such as an inkjet, dye sublimation, or laser printer, not to an imagesetter. Photoshop lets you control how your image is printed.
Monitors display images using light, whereas desktop printers reproduce images using inks, dyes, or pigments. For this reason, a desktop printer can’t reproduce all the colors displayed on a monitor. However, by incorporating certain procedures (such as a color management system) into your workflow, you can achieve predictable results when printing your images to a desktop printer. Keep these considerations in mind when working with an image you intend to print:
If your image is in RGB mode, do not convert the document to CMYK mode when printing to a desktop printer. Work entirely in RGB mode. As a rule, desktop printers are configured to accept RGB data and use internal software to convert to CMYK. If you send CMYK data, most desktop printers apply a conversion anyway, with unpredictable results.
If you want to preview an image as printed to any device for which you have a profile, use the Proof Colors command.
To reproduce screen colors accurately on the printed page, you must incorporate color management into your workflow. Work with a monitor that is calibrated and characterized. Ideally, you should also create a custom profile specifically for your printer and the paper you print on, though the profile supplied with your printer can produce acceptable results.
Displays the Print dialog box, where you can preview the print and set options. (Customized settings are saved as new defaults when you click Done or Print.)
For maximum efficiency, you can include the Print command in actions. (Photoshop provides all print settings in one dialog box.)
In the preview area at left, visually adjust the position and scale of the image relative to the selected paper size and orientation. Or to the right, set detailed options for Position And Size, Color Management, Printing Marks, and so on.
In Mac OS, expand the Color Management section, and select Send 16-bit Data to produce the highest possible quality in subtle graduated tones, such as bright skies.
Position and scale images
You can adjust the position and scale of an image using options in the Print dialog box. The shaded border at the edge of the paper represents the margins of the selected paper; the printable area is white.
The base output size of an image is determined by the document size settings in the Image Size dialog box. Scaling an image in the Print dialog box changes the size and resolution of the printed image only. For example, if you scale a 72‑ppi image to 50% in the Print dialog box, the image will print at 144 ppi; however, the document size settings in the Image Size dialog box will not change. In the Print dialog box, the Print Resolution field at the bottom of the Position And Size section shows the print resolution at the current scaling setting.
Many third-party printer drivers provide a scaling option in the Print Settings dialog box. This scaling affects everything on the page, including the size of all page marks, such as crop marks and captions, whereas the scaling percentage provided by the Print command affects only the size of the printed image (and not the size of page marks).
To avoid inaccurate scaling, specify scaling using the Print dialog box rather than the Print Settings dialog box; do not enter a scaling percentage in both dialog boxes.
Choose File > Print, and expand the Position And Size settings at right. Then do one of the following:
- To rescale the image numerically, deselect Scale To Fit Media, then enter values for Scale, Height and Width.
If you get a warning that your image is larger than the printable area of the paper, click Cancel. Then choose File > Print, expand the Position And Size settings at right, and select Scale To Fit Media.
Print part of an image
- With the Rectangle Marquee tool, select the part of the image you want to print.
- Choose File > Print, and select Print Selected Area.
- If desired, adjust the selected area by dragging the triangular handles on the perimeter of the print preview.
- Click Print.
Print vector data
If an image includes vector graphics, such as shapes and type, Photoshop can send the vector data to a PostScript printer. When you choose to include vector data, Photoshop sends the printer a separate image for each type layer and each vector shape layer. These additional images are printed on top of the base image, and clipped using their vector outline. Consequently, the edges of vector graphics print at the printer’s full resolution, even though the content of each layer is limited to the resolution of your image file.
Some blending modes and layer effects require rasterized vector data.