Powerpoint - On a Diet - Redux

Cheryl Chan (Dental Hygiene) stopped by to compress the two Powerpoint files full of 35 mm slide images she scanned last summer. I had established a high resolution scan setting for her, and a Photoshop batch process to make the images ready for adding to Powerpoint. The batch process is easy to forget. The high res images are 40 MB + each and 40 images in one presentation will cause a laptop to meltdown. No, not really, but a presentation with large images is not very responsive.

Our discovery is that Powerpoint 2004 on a Macintosh computer does not have a Toolbar > Picture > Compress function like the Windows version. So after compressing for web/screen the 400 MB presentation file became a 2 MB file. WOW.

Another way to compress presentations is to convert them to Acrobat (PDF) files. Sometimes just converting saves space, the 400 MB ppt file became a 150 MB pdf file. But Acrobat can compress files using the Advanced > PDF Optimizer function and dropped the file to 2.5 MB.

PDF files are ideal when adding to D2L - Desire2Learn or any other learning management system.

Recipe for Slides to Powerpoint

Bruce Pierini (Anthropology) has been anxious to complete the process he started last semester: digitize his slides and create Powerpoint presentations to enhance lectures. Well, remember that slide projectors are going away soon (Kodak is discontinuing the product line).

Bruce scanned images into two folders - Physical Verticals and Physical Horizontals. What? The batch process will resize the images and he needs to keep the landscape and portrait images together. The final sizes will be landscape 10 inches wide and portrait 7.5 inches tall. The files are all TIFF images and about 40 MB each!

Using Photoshop we recorded an action for resizing horizontal images and another action for vertical images. These new actions how up in File > Automate > Batch... and act on a folder full of images.

Here are the steps in testing this process:

1. Open an original image
2. Use Image > Image Size... > edit the pixel per inch field
3. Save the image as a new file
4. Open Powerpoint and insert image on a slide
5. Preview presentation to evaluate picture quality

In Photoshop, Window > Action to show Action Palette

1. Create a new action, name it - resize 10i 100px
2. Create a new action, name it - resize 7.5i 100px
3. Open a new image and apply the action

In Photoshop, File > Automate > Batch ...

1. Choose one of the resize actions
2. Select the folder of original images
3. Select the folder for processed images (destination)
4. Click OK

Watch the process happen ;-0

Bruce's original scans settings:

• high resolution 4000 pixels per inch
• 1.312 inches wide, .68 inches high
• 40 MB each - TIFF
  
• Processed images
• projector resolution 100 pixels per inch
• 10 inches wide, 7.5 inches high
• 2 MB each - TIFF
  

Our last step was to convert the TIF files to JPEG. Again, we tested these image by adding them to the test Powerpoint with four high quality images. In the presentation mode, watching a speck of detail on the TIFF and JPEG images - we could not tell the difference. The JPEG pictures are about 500 KB.

We recorded an Action to convert TIF to JPEG in a File > Save As sequence and ran this Batch on all images and subfolders (without consideration of landscape or portrait orientation). Photoshop easily ripped though this assignment.

Summary of file sizes

• 40 MB each - TIFF - original scans
  
• 2 MB each - TIFF - resized images
  
• 500 KB each - JPEG - compressed images
  

Adding pictures to Powerpoint can be done from the Insert menu or try 'drag and drop' from the Macintosh Finder to blank Powerpoint slides.

In his presentations, Bruce will use a black background so the images stand out.

This sequence is available for others to use. Thanks Bruce for being a digital pioneer!

Slide Scans to Powerpoint

Jennifer Griffin (Art Department) stopped by to checkout the new Nikon slide scanner. She will be scheduling time in the lab for scanning work. Over the last 18 months, Jennifer has become an expert in scanning and I look forward to learning her tricks. Already she has offered to help me fine tune the post scan BATCH processing to (1) create contact sheets of the images and (2) create a two-step process to resize images and change them from TIF to JPG. Then the images can drop right onto presentation slides. "Yes," she says, "I've attended the PhotoShop Scho0l of Hard Knocks and I can save you from some headaches!"

Right away Jennifer made an important suggestion: use the filename to distinguish vertical and horizontal slides. The batch process will change all slides to one length and vertical slides will loose image area. An alternative method is to have an additional folder for vertical images.

Put Powerpoint Files on a Diet

Sometimes your students will just want to print the presentation slides as a study guide handout. That's what Mick Dunne (Dental Hygiene) had in mind. He posted his vocabulary presentation for students to download. But the Powerpoint file is over 8 MB in size. The larger the file, the longer the download time.

Since Mick wanted his students to have the study guide handout, it was best to use Adobe Acrobat to create the printed view - with full color - for students to use. This file was well under 1 MB, just 335 KB!

Easy access to files is one half of the solution, making smaller files is the other half.