Presentation on theme: "Enhancing Digital Images: Some Basics STEM Earth Central August, 2005 Mort Sternheim, Holly Hargraves."— Presentation transcript:
Enhancing Digital Images: Some Basics STEM Earth Central August, 2005 Mort Sternheim, Holly Hargraves
Adobe Photoshop Elements 3.0 Many, many features Windows and Mac versions (some differences) Academic price about $53 (~$100 list) (govconnection.com, ) Simpler, easier to use, cheaper than Adobe Photoshop (~$600 list ) Free 30 day trial download from adobe.com
References and Help Photoshop Elements 3.0 for Dummies Excellent $21.99 list, $15.39 from Amazon.com Elements manual < Help Help has search options, tutorials How to palette in program
Today Basics Adjusting brightness, contrast (Levels) Adjust color Quick Fix Cropping Redeye Reducing file sizes for PowerPoint, web, Using Layers to make labels
Elements components View and organize photos Tags, collections, search by date …. Quickly fix photos (Quick Fix) Automated, menus Edit and enhance photos (Standard Edit) More control, options, tools, …. Make photo creation Web gallery, Slide show, Card, postcard, calendar, VCD, …
Getting Started Double click on the Photoshop Elements icon to start the program On the Welcome Screen, select Edit and Enhance Photos Use File Open, go to the Desktop, and then to SEC_Photos Double click on Alan.jpg to open that file. On the menu bar (top of screen), click on Window, and then on Undo History. This lets you track and undo changes
Adjusting Brightness and Contrast Useful for nearly every photo! On the menu bar select Enhance Adjust Lighting Levels You will get a screen with a levels histogram and three sliders just below it. Drag the rightmost slider to the left until it is under the end of the graph. (Brighter whites) Drag the leftmost slider a bit to the right. (Darker grays.) Drag the center slider to the right or left to choose the best midtones. Click OK.
Levels Histogram for Alan.jpg
Levels, cont. Use the Undo History palette to undo/redo Levels effects Try this exercise with Ilka.jpg To see a major improvement with Levels, try ibis.jpg Try Levels on underexposed photos such as Kathy.jpg or Oval Window.jpg
Adjusting Color Try Enhance Adjust Color Color Variations with one of these images. Experiment with some other Adjust Color options.
Quick Fix Fast, easy, somewhat limited Open Ilka1.jpg Select Quick fix. Note the Undo and Redo buttons that let you retrace your steps. Note menu options for General Fixes, Lighting, Color. These are not as powerful as the equivalent individual menu options, but easy to use and experiment with.
Cropping Trim off unwanted stuff; zoom in on birds, etc. Easiest way is with the Crop Tool. Open gps.jpg On Toolbox, click on Crop Tool Click at one corner of area you want to keep, drag to opposite corner, release. When you are satisfied, hit click on the check mark (commit) on the right side of the Options bar. Or, to start over, click on the cancel icon.
Adjusting crop boundaries You can drag any handle to modify that part of the boundary. Shift-drag on a corner handle constrains the proportions. If you position the cursor inside the box, you can drag the whole box to a new location. If you position the cursor outside the box, you can drag and rotate the box.
Cropping to specific sizes, resolutions Handy for preserving aspect rations, and for cropping and resizing to desired print formats. In the Options bar, note the Width, Height, Resolution boxes. Enter 6, 4, 300. (More on resolution later.) Click on a corner of the desired box and drag. The resulting box will be have 6/4 proportions. When you click on the check, the image will have 6 x 4 dimensions, and 300 pixels per inch.
Fixing Red Eye
Fixing Redeye Open smile.jpg Use the Zoom Tool to enlarge her eyes. Select the Red Eye Brush in the Toolbox. Click in the red area of an eye. This should remove the red eye, (If you want to adjust the effect, vary the pupil size and darken amount in the Options bar. This is seldom needed.) Open redeyegirls.jpg and fix their redeye
Pixels and Displays Screen images are made up of tiny squares called pixels (picture element). Pixels are usually 1/72 inch across. Today most people use 800 x 600 or 1024 x 768 pixel displays, or < 1 million pixels How large a given image appears depends on the screen settings! An image 800 pixels by 600 will fill the 800 x 600 display but not the 1024 x 768 display.
Downsizing Images Most people have displays with less than 1 Megapixel and cant see a larger image all at once Downsize pictures for PowerPoint, the web, or , usually to 0.5 Megapixels or less. This makes it faster to load (or download) Exception: You expect someone to make large prints from the image.
Why buy a 4 or 8 Megapixel camera? You cant see all those pixels at once on a screen. But, you can make use of them for zooming, cropping. You can also make larger, better prints with more pixels.
Checking Image Sizes Open Brie.jpg in Standard Edit or Quick Fix Select Image Resize Image Size You will see the following screen
Image size data Width:2272 pixels (7.573 inches ) Height:1704 pixels (5.68 inches) Channels:3 (RGB) Resolution:300 pixels/inch Numbers in inches (7.573, 5.68) define the size if the photo is printed. The width and height in pixels (2272 x 1704) define how it will fit on a screen The resolution (pixels per inch or ppi) how good the print will be; it means nothing for onscreen viewing. Channels (RGB) color, not grayscale
Changing Image Size for Screen Use Select Image Resize Image Size Make sure Constrained Proportions is checked For Width, enter 800 Height should automatically change to 600. Note the file size is now 1.37M (was 11.1M) Click on OK Note: You can resize a batch of files all at once using File Process Multiple Files
Saving the Image File Select File Save As. For File name, enter Brie1.jpg to avoid overwriting the original image. (.jpg format is the best image format for photos in most cases. It compresses the file while preserving nearly all the details.) Click on Save. In the next screen, select High Quality and then OK. (Note the image size is now 87k. The original Brie.jpg file size was 844k.)
Resolution and Printing For good ink jet photos, you need at least 150 pixels per inch (ppi) ppi is better For 8 x print, 150 x 150 x 8 x = 1.9 million Thus an 8 x 10 requires a 2 Megapixel image or better for good results. Set print size with Image Resize Image Size, changing Document Size Width, Height Or, use File Print or File Print Multiple Photos. (Picture packages, contact sheets …)
Layers Like sheets of transparent plastic on an overhead projector. Work more easily on one element of image – edit one layer at a time Combine, copy images Create text layers with labels, etc.
Adding labels with text layers Open 1ibis.jpg Click on Window and on Layers to display the Layers palette Right click on the Text tool in the toolbar Select horizontal type Position the cursor somewhere near its head Type the word head
Changing the appearance of text Use the move tool to position the label Click on the Text tool again Change the font, font size, and color of head using boxes in the option bar Use the icon next to the color option to warp the text Click the last icon to change the text orientation
More labels Click on the Text tool. Put you cursor near a leg and type leg Again, play with this label – move it, format it, etc. You can select the active layer by clicking on the appropriate layer in the layers palette. The active layer is indicated by a paintbrush in the second column and a blue field to the right.