Practice File Formats, Image Size and Saving Files

Transcription

1 Digital Imaging 1 Practice File Formats, Image Size and Saving Files Practice skills Saving layered PSD (Photoshop), TIFF and PDF files. Flattening and saving files as copies in alternate formats for print. Saving image as JPEG file for web. Observing image size. Saving separate layers as files. Making a Contact Sheet from a folder of images. Starting File: Open BallLyrs.psd file from Photoshop Samples folder or download from Blackboard. Choose File>Save As and direct this PSD to your class folder. Then click on new folder icon in the Save As dialogue window. Name the folder File Formats. Save this file with your name: name_balllayers. A PSD is the extension for Photoshop Native files. Native files may be opened on Windows or Macintosh platforms. Extensions are required in order to open Windows files. Open Preferences from the Apple Menu or the File menu on PC and choose File Handling. Be sure the following Options are selected: Append File Extension: Always and check Use Lower Case and Ask Before Saving Layered TIFF files. Click OK. Procedure: Saving a TIFF file: cross platform format for raster images for print. 1. With BallLyrs.psd image open, stretch the window bigger showing some gray background so you can see the Doc: size in lower left corner of window. This is a layered PSD or Photoshop file. Observe the files sizes in the lower left corner of the image window: 182 K (flat), 1.25 MB (layers). 2. Look at Image>Image size. Note size in pixels as well as kilobytes. Notice the Document size in inches in lower half of Images size dialogue screen. Close window. 3. Now go to File> Save As. From the Format: Pop up button, choose TIFF. Notice that there is an option to save the file with layers. Leave that checked for now. Add last name start of file name plus add 1. (name_ball_layers1.tiff). The original PSD should remain in your File Formats folder untouched. 4. Direct the file to this folder and Save it. When the TIFF options window opens observe the choices. 5. You may save TIFFs for Mac or PC platforms. The bit order varies between the two platforms, so use the option based upon the computer system used. (Mac or PC). Click OK. 6. The.tif layered version of the file should still be open. (Check the file name at the top of window.) 7. Select Save As again. Choose TIFF, but this time Uncheck Layers. Be sure copy is checked. Re-name this file by replacing lyrs with flat. Be sure your name is first, plus add 2. (name_ball_flat2.tiff). Save this file in your folder.

2 8. The layered Balllyrs.tiff should still be open since the last file saved was a copy. Open the flattened file. Look at the doc size numbers in the lower left edge of the window of both the layered and flattened files. (Window may need to be stretched larger to see it.) The files size of the flat version matches to the left and right of the slash whereas the layered version shows both the file as it would be flat as well as the file size of the image with layers. Saving a Photoshop PDF: cross platform format for print/web. 1. Select the BallLyrs version of the file. (Original PSD.) Go to File> Save As. From the Format pop up button, choose Photoshop PDF. T Layers are checked by default. Name file with name + pdflyers + 3 added to file name. (name_ball_pdflyr3.pdf) 2. When the save options open, choose the High Quality Print preset (for desktop printers). Leave Preserve PS Editing Capabilities and Optimize for Fast Web Preview. Click Save. 3. When ask, click Yes to save Photoshop Editing capabilities even though it is incompatible with earlier versions. 4. After saving the file, PDF file version remained open with the layers. Close this file. 5. Open the PDF file. It should open in Acrobat Reader (Reader is free and available for download. See Intro folder in Blackboard). The file may now be previewed as a PDF. 6. Close the Acrobat PDF file. continue. Saving a JPEG: cross platform for continous tone color images for web/internet. 1. Open the original Photoshop.PSD file. Go to File menu and select Save As again. 2. In the dialogue box next to Formats, choose Photoshop JPEG from pop up button. Note the file extension changed to jpg. Add to the file name the word low, your name and 4. Leave.jpg extension! Do not add periods or spaces in a file name. Underscores may be used. (name_ball_low4.jpg) 3. Click the Save button. Be sure this file is directed to the same folder as all the other previously saved images. 4. When the JPEG optimization window opens, select a low level (1-2) and leave other selections at their defaults. Note a copy of this file will be saved. Click OK The higher the number the less information will be thrown out. If you lower the optimization level, JPEGs throw out information, leaving a splotchy look in parts of the image. These are referred to as JPEG artifacts. The file size on hard disk gets smaller, but when it is opened in Photoshop will expand to size based upon resolution, bit depth and total pixels in the image. However the artifacts remain. 5. The original image should still be open because this should have saved a copy. Check the file name at the top of the open window. (This is the same whether a PSD, TIFF or PDF file is saved as a JPEG file from Photoshop.) 6. Do Save As again and replace word low with high plus # 5. When ask, change the optimization level to a high 12. Click OK. (name_ball_high5.jpg) 7. Files may also be saved for the web using the File> Save for Web feature. This will be reviewed later. Be sure all 5 files saved so far are all in one folder.

3 Checking File Size and Resampling 1. Open each of the two jpegs saved as low and high into Photoshop. Move images side by side. Zoom each image to % (highlight 100% in lower left window and change %). Use the hand tool to move the images so that the same area is being compared. Look at each image. Can you see the blurry artifacts in the file saved with a low JPEG setting? This is the trade off to making smaller* file sizes using the JPEG format. *The JPEG low image will be smaller saved on the disk (take up less room.) And it will be smaller uploaded to a web page taking less time to download. 2. Stretch the window larger and note the document sizes of the two files in the lower left corner of the windows. They should be the same! Even though the two files were saved in different qualities they will open expanded and are the same size in Photoshop based upon the resolution and dimensions of the actual image. 3. Select the high JPEG file. Go to Image>Image Size window. Please note the following: the total Pixel Dimensions (file size in kilobytes), the width in pixels and the height in pixels. This is the Image Size. Then Notice the width and height in inches. This is the Document Size the image will print. The resolution of 72 dpi is considered to be low resolution. Note Resampling is checked. Keep this dialogue box open, go to step With Resample checked change the number of the resolution to 144. Notice how the Pixel Dimensions and file size changed. Note how much bigger the file size became. Extra pixels have been added to this image making it larger. Look at the Document dimensions. That did not change. Since there are more pixels in the same amount of space the pixel size is smaller and the image should appear sharper (clearer) or less pixelated. 5. With the same dialogue still box open, change the resolution number back from 144 to 72. Uncheck Resample in the Image Size dialogue box. Now change the resolution from 72 to 144. Note, did anything change? File size? Document dimensions? The file size did not change because no pixels were added or subtracted to the image! The pixels are redistributed causing the pixels to become smaller and the dimensions of the image are half as big.

4 6. Cancel the Image size dialogue box without saving any changes. Close the JPEG files without saving again. (Resaving JPEGS increases the artifacts in the images and degrades the image further.) Conclusion: To understand resampling and how it affects image size is very important. Resampling will add or subtract pixels to an image. The pixels added are best guess pixels. The word for this is interpolated. It is best to avoid resampling images. Whether you add or subtract pixels the image is always downgraded and becomes softer and fuzzier looking. To stretch or resample a low resolution small image bigger is even worse as pixels are stretched larger and will look even more pixelated. Saving separate Files from Layers. 1. Be sure the layered PSD image file is open. (It should be in your folder.) 2. Go to File>Scripts. Choose Export Layers to Files. 3. When the dialogue box opens, note that you can choose different file formats from the pop up window. The choice provided is based upon the original file format. Leave this PSD. Be sure your name is in front of ball layers. Then click run button. The files should save in your folder where the PSD file was first stored and opened. Because there were 5 layers in the file, there should be 5 additional files saved in your folder with the layers name and number appended. (Paul_BallLyrs_0000_Sun.psd) 4. Close this PSD file. Keep Photoshop open. Creating Contact Sheet using Bridge in CS 4 or 5. CS 4 and 5 uses Bridge to make contact sheets. This is the recommended method. 1. Launch Bridge from the Icon on the Options Bar or choose File>Browse in Photoshop. 2. Browse to and select your folder File Formats. 3 Click to open the folder. Look at the contents to see 11 images. By default the Bridge Essentials view is open. See example right. To Reset views to their defaults select Reset Standard Workspaces from the down arrow on the right end of the Essentials bar. 4. Select Output view at the top right corner of the window in line with the Essentials bar or choose it from the down arrow. The middle and right panels will change. 6. Click on PDF button.. Make a custom layout as follows. 7. Expand Document settings. Choose Page Preset: US Paper 8.5 x 11 inches. Check vertical format (default) 8. Use the Shift key to select all 11 contiguous images. The Command key (Mac) or Control (Win) may be used to select non contiguous mages in the folder. This is an option. See browser window example next page.. 9. Expand the Layout menu. In Columns type in 3 and Rows type 4 since 11 images are in this folder and all are selected. This defines the number of images for a one page contact sheet. 10. Click on the Refresh Preview button near the top of the side panel. This allows you to see the layout. 11. In the lower part of the right side panel, click the Save button. Name this name_contactsht. Direct this contact sheet to the File Formats folder. This should create 11- images on a one page contact sheet. See example screen shot of final contact sheet lower right on the next page.

5 Making a contact sheet of your images using Automatic plug-in. The plug in is automatically installed in CS 2-3. The plug-in for Photoshop CS 4 is available on program disk to install manually. If using CS 4 or 5, skip this section. 1. All the images should be in one folder to make a contact sheet. No image needs to be open to make a contact sheet. In Photoshop choose File> Automate> Contact sheet II. 2. In the contact sheet dialogue (right) click the Choose button and browse to your File Formats folder. Select this folder. You should have 11 images in it including the 5 images from layers. 3. Change the Resolution to 72 ppi (since 300 ppi is not needed.) 4. Under Thumbnails, change Columns to 3 and Rows to 4. (This maximizes the size of the images and fills the 8 x 10 inch page.) Leave other options as they are. Click OK. A contact sheet is automatically created and is open in Photoshop. File>Save As the contact sheet adding your name to the file name. You may save this as a PSD, PDF or JPEG file. Save the contact sheet in your folder for check off. Lab Submission: Submit to instructor as directed and get checked off for completed work. Online students: Submit the contact sheet saved as a PDF or JPEG file. Upload this to Blackboare as specified for check off.