Go to File->New and open up a new canvas (this will be the background layer)
Create background by setting size of final sheet to be printed (e.g., 10.4 inches X 8.25 inches for landscape orientation)
Set resolution to printer resolution (e.g., 300 dpi)
Set mode to RGB
Give the image montage a filename

For each image file to paste onto this page, do the following: (NOTE: Be sure that the images are in a format that PhotoShop can recognize, e.g., TIF, PhotoShop)
1) File->Open and select image(s) from disk or where ever you have stored them
2) Image->Image Size and resize by entering values in dialog box by selecting Print Size in inches (e.g., 3 inches X 3 inches)

Check Constrain Proportions
Adjust resolution so that output is the same as background sheet (e.g., 300 dpi) Resample Image should be checked for alternative Bicubic Click OK
NOTE: Image will look larger because the monitor is trying to show 300 dpi on a 72 dpi screen. Zoom Out by striking Apple (or CTRL) and + and – keys
• Use Select Tool and select whole image (or Apple/CTRL-a)
• Choose Edit->Copy (or Apple/CTRL-c), then click on blank montage (background) page, then choose Edit->Paste (or Apple/CTRL-v)
• Use Move Tool (top right on tool bar) to place image where you want it to be
• Save montage when you are done in PhotoShop to preserve layers—this will allow you to alter each layer individually if needed)

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