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ADOBE PHOTOSHOP CS2
User Guide
You can create an HDR image using multiple photographs, each captured at a different exposure. In Photoshop, the
Merge To HDR command lets you create HDR images from multiple photographs. Because an HDR image contains
brightness levels that far exceed the display capabilities of a standard 24-bit monitor or the range of tones in a printed
image, Photoshop lets you adjust the preview of the HDR image so it can be viewed on a computer monitor. Some
Photoshop tools, adjustments, and filters can be used with HDR images. If you need to print the image or use
Photoshop tools and filters that don’t work with HDR images, you can convert the HDR image to an 8- or 16-bits-
per-channel image.
Working with HDR images
Photoshop lets you use the following tools, adjustments, and filters with 32-bits-per-channel HDR images:
Adjustments
Channel Mixer, Photo Filter, and Exposure.
Note:
Although the Exposure command can be used with 8- and 16-bits-per-channel images, it is designed for making
exposure adjustments to 32-bits-per-channel HDR images.
Blend Modes
Normal, Darken, Multiply, Lighten, Linear Dodge, and Difference.
Editing Commands
Fill, Stroke, Free Transform, Transform, Image Size, Canvas Size, Rotate Canvas, Crop (with
rotation and resize), and Trim.
File Formats
Photoshop (PSD, PSB), Radiance (HDR), Portable Bit Map (PFM), OpenEXR, and TIFF.
Note:
Although Photoshop cannot save an HDR image in the LogLuv TIFF file format, it can open and read a LogLuv
TIFF file.
Filters
Average, Box Blur, Gaussian Blur, Motion Blur, Radial Blur, Shape Blur, Surface Blur, Add Noise, Fibers, Lens
Flare, Smart Sharpen, Unsharp Mask, De-Interlace, NTSC Colors, High Pass, and Offset.
Modes
RGB Color, Grayscale, conversion to 8 Bits/Channel or 16 Bits/Channel.
Tools
Marquee tools, Move tool, lasso tools, Crop tool, Slice tool, Clone Stamp tool, History Brush tool, Path
Selection tool, Direct Selection tool, pen tools, annotation tools, Eyedropper tool, Color Sampler tool, Measure tool,
Hand tool, and Zoom tool. Some tools work with supported blend modes only.
See also
“To use the Exposure adjustment” on page 292
The Merge To HDR command
Use the Merge To HDR command to combine multiple images (with different exposures) of the same image or scene,
capturing the dynamic range of a scene in a single HDR image. You can choose to save the merged image as a 32-bits-
per-channel HDR image.
Note:
It’s also possible to use the Merge To HDR command to save the merged image as an 8- or 16-bits-per-channel
image. However, only a 32-bits-per-channel image can store all the HDR image data; 8- and 16-bits-per-channel images
will be clipped.
Keep the following tips in mind when you take photos to be combined with the Merge To HDR command:
•
Secure the camera to a tripod.
•
Take enough photos to cover the full dynamic range of the scene. You can try taking at least five to seven photos,
but you might need to take more exposures depending on the dynamic range of the scene. The minimum number
of photos should be three.
