Photoshop can create images of various aspect ratios so that they appear properly on devices such as video monitors. You can select a specific video option (using the New dialog box) to compensate for scaling when the final image is incorporated into video.
The Film & Video preset also creates a document with nonprinting guides that delineate the action‑safe and title‑safe areas of the image. Using the options in the Size menu, you can produce images for specific video systems—NTSC, PAL, or HDTV.
Safe zones are useful when you edit for broadcast and videotape. Most consumer TV sets use a process called overscan, which cuts off a portion of the outer edges of the picture, allowing the center of the picture to be enlarged. The amount of overscan is not consistent across TVs. To ensure that everything fits within the area that most TVs display, keep text within the title‑safe margins, and all other important elements within the action‑safe margins.
A. Action safe area (outer rectangle) B. Title safe area (inner rectangle)
If you are creating content for the web or for CD, the title‑safe and action‑safe margins do not apply to your project because the entire image is displayed in these media.
To help you create images for video, Photoshop has a Pixel Aspect Ratio Correction viewing mode that displays images at the specified aspect ratio. For more accurate previews, Photoshop also has a Video Preview command that lets you immediately preview your work on a display device, such as a video monitor. To use this feature, you must have the device connected to your computer via FireWire (IEEE 1394). See also Preview your document on a video monitor. For more information on FireWire (IEEE 1394), see Apple’s website.
Both Adobe AfterEffects and Adobe Premiere Pro support PSD files created in Photoshop. However, if you’re using other film and video applications, you might consider these details when you create images for use in video:
Some video-editing programs can import individual layers from a multilayer PSD file.
If the file has transparency, some video-editing programs preserve it.
If the file uses a layer mask or multiple layers, you might not have to flatten the layers, but you might want to include a flattened copy of the file in PSD format to maximize backward compatibility.
Frame aspect ratio describes the ratio of width to height in the dimensions of an image. For example, DV NTSC has a frame aspect ratio of 4:3 (or 4 width by 3 height) and a typical widescreen frame has a frame aspect ratio of 16:9. Some video cameras can record various frame aspect ratios. Many cameras that have a widescreen mode use the 16:9 aspect ratio. Many professional films have been shot using even wider aspect ratios.
Pixel aspect ratio describes the ratio of width to height of a single pixel in a frame. Different video standards use different pixel aspect ratios. For example, many computer video standards define a 4:3 aspect ratio frame as 640 pixels wide by 480 pixels high, which results in square pixels. The computer video pixels in this example have a pixel aspect ratio of 1:1 (square), whereas the DV NTSC pixels have a pixel aspect ratio of 0.91 (nonsquare). DV pixels, which are always rectangular, are vertically oriented in systems producing NTSC video and horizontally oriented in systems producing PAL video.
If you display rectangular pixels on a square-pixel monitor without alteration, images appear distorted; for example, circles distort into ovals. However, when displayed on a broadcast monitor, the images appear correctly proportioned because broadcast monitors use rectangular pixels.
When copying or importing images into a nonsquare pixel document, Photoshop automatically converts and scales the image to the pixel aspect ratio of the document. Images imported from Adobe Illustrator are also properly scaled.
A. 4:3 square-pixel image displayed on 4:3 square-pixel (computer) monitor B. 4:3 square-pixel image interpreted correctly for display on 4:3 non-square pixel (TV) monitor C. 4:3 square-pixel image interpreted incorrectly for display on 4:3 non-square pixel (TV) monitor
By default, nonsquare pixel documents open with Pixel Aspect Ratio Correction enabled. This setting scales the image so it appears as it would on the nonsquare-pixel output device (usually a video monitor).
You can simultaneously view an image with the Pixel Aspect Ratio Correction turned on and off. With the nonsquare pixel image open and Pixel Aspect Ratio Correction enabled, choose Window > Arrange > New Window For [name of document]. With the new window active, choose View > Pixel Aspect Ratio Correction to turn off the correction.
To set output options before previewing the image, choose File > Export > Video Preview.
To view the image without setting output options, choose File > Export > Send Video Preview To Device.
When creating images for video, you can load a set of video actions (included with Photoshop) that automate certain tasks—such as scaling images to fit video pixel dimensions and setting the pixel aspect ratio.
For video images, actions automate tasks such as constraining the luminance range and saturation levels to comply with broadcast standards, resizing and converting to nonsquare pixels for use in DVD slide shows (NTSC and PAL, standard and widescreen aspect ratios), creating an alpha channel from all currently visible layers, adjusting image areas (especially thin lines) that are likely to cause interlace flicker, and generating a title‑safe overlay.
You can create a custom pixel aspect ratio in existing documents, or delete or reset pixel aspect ratios previously assigned to a document.
The new custom pixel aspect ratio appears in both the Pixel Aspect Ratio menu of the New dialog box and in the View > Pixel Aspect Ratio menu.
Replaces the current pixel aspect ratios with the default values plus any custom pixel aspect ratios. This option is useful if you deleted a default value and want to restore it to the menu but also want to retain any custom values.
Replaces the current pixel aspect ratios with the default values. Custom pixel aspect ratios are discarded.
Cancels the command.
You can import a Photoshop (PSD) file directly into an After Effects project with the option of preserving individual layers, layer styles, transparent areas and layer masks, and adjustment layers (preserving the individual elements for animation).
Note: For best results, work in RGB mode, which After Effects uses. After Effects CS3 and later can convert files from CMYK to RGB. After Effects 7 and earlier cannot.
Before you export a layered Photoshop file for use in After Effects, do the following to reduce preview and rendering time and to avoid problems with importing and updating Photoshop layers.