Adjusting Digital Images
Learner Section
This lesson guides students through:
- Managing digital image files on their personal computers.
- Deciding what needs to be done to change or improve images they have for use in Treehouse building.
- Adjusting images (correct size, rotate, brightness level, cropping) in preparation to upload images to the Tree of Life website (editing step #3 Upload/Edit images).
| Go to the Teacher section | Learners |
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Learner Tasks
Student Instructions:
Rotating An Image
- With your image file opened in Microsoft Paint, decide whether the image needs to be rotated. View an example of a rotated image. If your image is upside down or turned on its edge, then you will need to rotate it. If not there is no need to rotate your image. If your image does need to be rotated move on to step two.
- With your image showing in the Paint window, click on IMAGE at the top of the window and select FLIP/ROTATE.
- Within the small window that opens, select ROTATE BY ANGLE, and then decide by how many degrees your image needs to be rotated—90, 180, 270, 360. Remember that your images can only be rotated clockwise or to the right. In some other image editing programs you can choose to flip your image horizontally, vertically or by a pre-set angle.
Resizing An Image
- With your image showing in the Paint window, you first need to determine what size your image is. The units of measurement that we are interested in are pixels. Pixels measure how much digital space an image takes up on your computer. The larger the image, the more pixels it requires. Images to be uploaded on to the Tree of Life should be sized so that the largest dimensions (width or height) are no more than 450 pixels.
- To find out about the pixel dimensions of your image, click on the IMAGE button at the top of the window, and then select ATTRIBUTES. It is important that you only view this window. Do not change any of the information in this window. The only exception to this rule is to make sure that below the readings for width and height that the box for PIXELS is checked. How wide and how high is your image? Write the largest of these numbers down. This is your largest dimension.
- Now look at the table you were given at the beginning of the period. In the column labeled LARGEST DIMENSION OF YOU IMAGE, locate the range into which your largest pixel measurement fits. Then look in the corresponding row in the column labeled % DESCREASE. This number is how much you will need to shrink your image, in percentage form. Write the percentage down. Click OK on and the ATTRIBUTES window will close.
- Click on the IMAGE button at the top of the Paint window, and selected STRETCH/SKEW. Notice in the Stretch box there are readings for both the horizontal and vertical dimensions of your image. They both should both read 100%.
- On a sheet of paper subtract the percent you acquired from the table from 100. This is the number you will need to enter in both of the boxes where it now reads 100%. (For example, if your percent decrease was 60, then you subtract that from 100 to get 40 and enter 40.) Be sure to enter it for both the horizontal and vertical box. If you do not your imaged will be skewed and not look good. Click OK and take a look at your image.
- To make sure everything work correctly repeat step 2 to see the new dimensions of your image.
Cropping an Image
Saving an Image as JPEG
1. Now that you image looks the way it should, you need to make sure that it is saved in the correct format.
2. With you image showing in the Paint window, click on FILE at the top of the window and selected SAVE AS. Within the new window that opens, find your folder and select it the correct location or folder and type in the file name they want associated with their images. Clicking SAVE AS in the lower right hand corner completes the lesson. You can close the Paint application and log off your computer.