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About Adobe Photoshop

Adobe Photoshop is the leading digital image editing application. Photoshop can help prepare images to be used as Web graphics or printed pieces. Photoshop allows the user to edit images in a multitude of ways including:

  • Color Correction – Adjusting color within an image so it best represents the original scene.
  • Image resizing – Adjusting the physical size of an image.
  • Correcting imperfections – The removal of flaws in an image or repairing damaged information within an image.

NOTE: It is a best practice to be viewing content that needs correction at a view percentage of at least 75%. 

Correcting Image Brightness and Contrast

  1. Select Image from the dropdown menu bar.
  2. Hover over the Adjustment.
  3. Click on Brightness/Contrast from the drop-down menu.
  4. Drag the Brightness and Contrast slider to the left or right applying the desired correction.
  5. Check and uncheck the preview option to see the potential changes.
  6. Repeat steps 4-5 until desired correction is reached.
  7. Select the OK button when finished.

Adjusting Tonal Range With the Levels Tool

  1. Click the Image dropdown menu.

Levels window

Figure 1: Levels window

  1. Hover over the Adjustments.
  2. Click on Levels(Ctrl+L).
  3. Select on the Black.
  4. Click on the darkest point in the image to set a shadow point. This may take a few clicks in a variety of locations.
  5. Select the White eyedropper.
  6. Click on the brightest point in the image to set a white point.
  7. Drag the Midtone Slider to the left and right to adjust the midtone information in your image.
  8. Repeat steps 4-8 until desired effect is reached.
  9. Click OK when finished.

NOTE: An image may not have a true black or white point that could be selected. In this case it is alright to set one point or the other and adjust the midtown slider as needed. The Auto button would be used as a last resort.

Color Correction With the Color Balance Tool

Images can sometimes have an overall color cast that one would want to remove.

  1. Select Image from the dropdown tool.
  2. Hover over the Adjustment.
  3. Click on Color Balance.
  4. Drag one of the three sliders to the left or right depending on the color you want to add or remove.

Figure 2: Color Balance window

  1. Check and uncheck the Preview option to see the potential changes.
  2. Repeat steps 4-5 as needed.
  3. Click OK when finished.

Correcting Imperfections

Photoshop has several healing tools capable of correcting small to large imperfections.

Spot Healing Brush – Small imperfections

  1. Select the Spot Healing Brush from the toolbar. Choose a slightly larger brush tip then the imperfection from the tool specific menubar.
  2. Click the imperfection.
  3. Repeat steps 2-3 to cleanup remaining imperfections that are small in size.

Healing Brush Tool – Medium imperfections

  1. Select the Healing Brush tool from the toolbar.
  2. Choose a slightly larger brush tip then the imperfection from the tool specific menubar.
  3. Hold down the Alt key on your keyboard while clicking in an area near the imperfection that best represents the content you want to correct.
  4. Release the Alt key.
  5. Click the imperfection.
  6. Repeat steps 2-5 to correct medium sized imperfections.

Patch Tool – Large imperfections

  1. Select the Patch Tool from the toolbar.
  2. Make sure the Patch dropdown reflects Normal.
  3. Draw a selection around the imperfection.
  4. Click and drag the selection to an area that would best represent the area you want to correct.
  5. Repeat steps 3-4 until satisfied.

NOTE: It is common to use more than one healing tool to correct one area.

Resizing an Image

You can resize an image in either Pixels or Inches. Image Resolution will be dependent on how you choose to output your image.

  • Web = 72 pixels per inch
  • Newsprint = 150-170 pixels per inch
  • High-end color reproduction = 300 pixels per inch or higher
  1. Click the Image dropdown menu.
  2. Click Image Size.
  3. Uncheck Resample Image to lock the resolution with the height and width.
  4. Set the Resolution field to 300 pixels per inch.
  5. Click OK to accept changes.

Setting the Color Mode

Color mode is specific to the image will be output. Images intended to be used on the Web will need to be in RGB mode (Red, Green, and Blue) for output. Images that are intended for print will need to be saved in CMYK mode (Cyan, Magenta, Yellow and Black). Grayscale can be selected for both Web and Print use.

  1. Select Image from the dropdown menu.
  2. Hover over Mode.
  3. Click on desired mode for output.

Applying Sharpening to an Image

No set values can be set for applying sharpening. How much sharpening to apply depends on image size and the amount of detail within an image. When working with a large image more sharpening may need to be applied to see a change. If an image has a great amount of detail then less sharpening may be in order.

Using the Unsharp Mask to Apply Sharpening

  1. Click the Filter dropdown menu.
  2. Hover over the Sharpen option.
  3. Select Unsharp Mask from the menu.
  4. Adjust the Amount slider as needed.
  5. Adjust the Radius slider as needed.
  6. Adjust the Threshold slider as needed.

NOTE: One can always apply more sharpening to an image. One cannot reduce the amount of that has been applied to an image. When in doubt apply less sharpening.

  • Amount – Determines the aggressiveness of the sharpening action.
  • Radius – Determines how wide and area at the transition will be affected.
  • Threshold – Determines how much difference there must be between two adjacent pixels before any change is made.

Saving your Image for Print

Images intended for print should not be compressed like Web graphics. The two printing formats that allow you to control compression are Encapsulated PostScript document (EPS) and Tagged Image File Format (TIFF).

  1. Click the File dropdown menu.
  2. Select Save As.
  3. In the Format dropdown menu select .EPS or .TIFF. These are both suitable for printing file formats.
  4. Click Save.
  5. Ensure that no image compression will be applied to the saved image.
  6. Click OK to finalize the save.
Training for: 
Faculty
Staff
Students
Type of Training: 
DocumentationDocumentation
Training Topic: 
Creative
Service or Technology: 
Adobe Photoshop
Training Level: 
Introduction

Training for: 
Faculty
Staff
Students
Type of Training: 
DocumentationDocumentation
Training Topic: 
Creative
Service or Technology: 
Adobe Photoshop