Dust and noise will cause some spots on your images. Often they are white pixels, but they may be any color. Higher resolution seems worse, I think just because there are so many more pixels. If the spots are dust, it could be on either the glass or the photo. If it is noise, it will be in random spots from scan to scan of the same image. Whatever, they need to come out.
The UnSharp Mask will emphasize these spots and make them real sharp.
The Clone Tool is a very valuable friend that makes quick work of removing these spots. Most image programs have about the same tool. Photoshop, PhotoImpact, Paint Shop Pro, they all work much alike. The Clone Tool copies or clones a few neighboring pixels from one area to another. It is like a paintbrush, but with colors that match very closely, invisibly. For important images, I go over the entire image quickly and simply remove all of the spots all before saving the file.
Removing the spots can make a dramatic difference in the perceived quality of the image.
See the Help menu of any photo program under Clone Tool for your specifics, but all the programs work similarly. Paint Shop Pro uses the two-connected-brushes icon for the Clone Tool, and that is the idea of how it works, to copy from one brush to the other. Photoshop uses a Rubber Stamp icon.
The Clone Tool has parameters on the Attribute Toolbar. To remove spots, I usually use a 5 pixel round brush, Transparency = 0, and Soft Edge = 10. These parameters are not very important, but don't use too large a brush, it can make it easier to detect (but you can use a fuzzy brush, with feathered edges). Remember the Undo menu when you say Oops. I work with the image Zoomed In to enlarge to 2X size, and sometimes larger. I adopt a methodical sweep of the image area to remove the spots. It normally only takes a minute, and it makes a big difference.
To begin with the PhotoImpact tool, hold down the Shift key, and click the mouse next to the spot you want to cover. In Photoshop, it is the ALT key, in Paint Shop Pro, it is a Right mouse click, and in PhotoDeluxe, a source target appears which you drag to the correct location. See your specific help file under Clone Tool. But otherwise, then they all work about the same. Click nearby the spot on the same color and texture that you want to copy over the spot. It is usually not critical.
The brush size is often important and useful, there are choices of brush size and opacity and edge feathering, smaller is often better. Then release the Shift or ALT key or Right Mouse button. You have defined the source point. Then click on the target spot to cover it with that color.
Here's the thing: That first such target click establishes a direction and a distance from the original source click, which is remembered. Every subsequent click will copy or clone the pixels from that direction and distance, but relative to the current location where you clicked (the spot). The programs show a new source crosshair that moves with you to guide you. You just go click, click, click to cover many spots, anywhere on the image, and it will always copy from that nearby direction and distance with respect to each clicked spot (except PhotoDeluxe 2.0 makes you drag the source spot to the new location manually). The CTRL-Z Undo will take back an individual click if you mess up. You can define a new source point again at will, to specify a new distance/direction.
|Don't get carried away, you might take out a few bigger spots that
should be there! |
These larger spots are a little harder to retouch, but not much. Each spot is covered by many clicks of a smaller brush. Enlarge it to 200% or 300% size to work on it, and it will be easier. The Clone Tool will become one of your best friends, you'll love it.
The main point is about easily covering the tiny dust and noise spots in your scanned images, every scan needs a bit of that. However, you can see that there's lots of things you can do with the Clone Tool to enhance your image.
You can also drag the mouse, and the same rule applies, it copies the imaginary line from that same direction and distance. You can paint entire areas this way. This is sometimes useful when your image picked up some of the edge of the photo. If you don't want to crop it, you can paint over the visible edge with the nearby image colors.
Hint: If using Photoshop, be sure to go into menu File - Preferences - Cursors, and select Brush size. Then the clone cursor will be a circle the size of the selected brush, and you can see what you're doing.
Adobe PhotoDeluxe has this tool at menu Tools - Clone (I like it least of all because its source point is fixed until you move it manually). PhotoDeluxe also has a filter at menu Quality - Remove Dust/Scratches that can specify a Radius and Threshold parameter. Use the smallest Radius and largest Threshold that hides the spots and does not blur (it's gonna blur a bit). Radius = 1 and Threshold = 100 seems about right, then sharpen with the Unsharp Mask filter. Photoshop has it too.
The typical Clone tool won't work in line art mode. For cleaning upline art documents to remove any black spots or edges (or anything), the easy way is to just enclose a large area of black spots with the standard Selection Tool, and then CUT (CTRL-X) them to the Clipboard (discarded, ignored, forgotten). The fill color will automatically be the background color, white in line art mode.