Let define our terms. I see confusion. PDF - This is a file created by Adobe and used to display documents that can include both images and . RGB - This is a color scheme Red Green Blue. This is from the days of color TV when the colors were red green and blue. You choose RGB if you want your PDF to be in color or preserve color objects within. You choose this if you want to preserve color in your PDF the best that is possible. (There may be other options that a printer professional would know more about.) Grayscale - (Not the fictional disease in GOT here.) This is a color scheme that only uses gradations of colors from white to black. It is better than just black and white and nothing to represent in between colors. Use this option if your PDF is mostly black and white color is not important or where you are going to use it is not in color. You might use grayscale version of a photo to put in your printed newsletter that is printed in black and white at Office Depot. If you plan to print lots of copies of your PDF black and white is cheaper to print. Color is more expensive. However a color print may have more value so you have to decide what is more important. Most marketing print jobs are in color (as you can see) so I think the budgets are big at thosepanies. Your budget purpose of PDF and how many PDF copies are what determine whether you use color or grayscale. italic To save money you can make a few large print jobs as posters or inside standees. Use grayscale for mass copies. Grayscale can be very effective with a skilled designer.