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Image Enhacement Tips & Tricks [2008.05.13]

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This page will provide basic instructions on how to remove scratches and folded edges, and also how to modify the color balance, brightness and contrast, and sharpness of a photo. All of the following instructions apply to Photoshop CS3 and higher.

The Starting Point | Brightness/Contrast | Image Sharpening
Removing Scratches | Color Balance | Finished Product

The Starting Point

This is a picture I had in my wallet - you can see that the corners are folded, there are scratches and holes in the picture, it's somewhat blurry, and the colors are faded. It's not too bad, but you can easily make it look much better.

First, make sure your picture is in "RGB" mode. This can be changed by clicking on the "Image" menu at the top of the screen, then going down to the "Mode" sub-menu, then selecting "RGB." This will allow you to use the sharpening filter to make the picture look more in-focus.


NOTE: If during the process of touching up your photo you make a mistake, you can go under the "Edit" menu at the top of your screen and select "Step backward". This will reverse the last thing you did to the photo.


Adjusting Brightness/Contrast


The first thing I did was to fix the brightness/contrast. Open the "Image" menu at the top of the screen, then open the "Adjustments" sub-menu, then select "Brightness/Contrast..." as shown in the image below on the left.

Brightness/Contrast Control Window

This will bring up the Brightness/Contrast control window shown above on the right. In the Brightness/Contrast window, you can either move the sliding triangles around on the line, or you can enter in values (positive(+) or negative (-)). I turned the Brightness up just a little, and the Contrast up about twice as much as the Brightness, which brought the colors out from the background, making Andy and the horse look less flat

Sharpening The Image


Next I ran the "Sharpen" filter on the picture to make it appear less blurry. Open the "Filter" menu at the top of your screen, the open the "Sharpen" sub-menu, then choose "Sharpen" (this can be done multiple times, or you can choose "Sharpen More" for especially blurry photos). You should be able to notice a difference in the quality of the photo after one or two Sharpen filters - don't do it too much, or the picture will become very grainy and it will look rough-textured.


Removing Scratches & Other Damage


Next I worked on getting rid of the damaged corners and the scratches. I did this by using the "Clone Stamp" tool. To the right is an example of what the Clone stamp does. You press "option" and select an area you want to clone, then when you click the mouse again on a new area, it will clone the area you selected ON TOP of the new area, thus making it look undamaged (when you're actually just copying one area and moving it over another).


Here's how it works: You select the Clone Stamp tool from the toolbar on the left side of the screen. Then choose an appropriate brush size by either clicking on the "Brush Preset Picker" selector located on the option toolbar or right-clicking on the image to bring up the "Brush Preset Picker" window.

The size of the brush depends on the overall size of the area you will we working on. I chose a fairly small brush as I was touching up several small sections.


Brush Preset Picker Window

With the Clone Stamp, you move the mouse over an undamaged area (which looks similar to the area you want to fix), hold down the "option" key (located to the right and left of the spacebar on your keyboard), and click the mouse button once. Now move the mouse over the area you want to fix, and click the mouse again (or, if it's a big area, click and hold the mouse and move the mouse around over the damaged area).

To select an area to clone:

Then release option and click and drag the mouse over the area you want to fix. Repeat this procedure until you have painted over all of the damaged areas. You can also zoom in on an area if you need to be able to paint finer details by clicking on the Magnifier Tool on the toolbar at the left of your screen:

You can zoom in by clicking the mouse over the desired area, and zoom out by holding down the "option" key and clicking the mouse.

Here's the same picture after I covered up all the damaged areas using the Rubber Stamp. Notice the corners look smooth and all of the large scratches are gone (I used the Magnifier tool to zoom in to fix the large white scratch next to his leg).

Adjusting the Color Balance


Once you've covered up all of the damaged areas, you can also fiddle with the Color Balance in the picture (to give the picture a little more life). Open the "Image" menu at the top of your screen again, then open the "Adjustments" sub-menu again, then select "Color Balance..." as in the picture below.

This will open up the Color Balance window.

As in the Brightness/Contrast window, you can either drag the triangle sliders around or you can type in positive and negative values in the boxes above the sliders. With the Color Balance tool you can modify the Shadows, Midtones, and Highlights of a picture by clicking on their respective buttons at the bottom of the window and changing the values of each color. For this example I turned up the Red, Green, and Blue values for the Shadows, Midtones, and Highlights, and as you can see it made a noticeable difference:


Before Color Correction


After Color Correction

The Finished Product



Original Picture

After Modifications

As you can see, these basic steps using Adobe Photoshop have dramatically improved the overall appearance of the original photograph. The final image is cleaner, sharper, and has much more warmth and richness than the original.

Please be aware that Photoshop is a very complex application with many different image manipulation tools, filters, and enhancers too numerous to describe here. These instructions cover the basics of image enhancement and illustrate just a fraction of what can be accomplished with Photoshop.

If you are interested in learning more about Photoshop or image manipulation and enhancement, I recommend that you invest in either a good Photoshop reference book (like the MacWorld Photoshop Bible), or a Photoshop class like those offered by the Marriott Library, click here for available classes.