When using photos and other graphics in PowerPoint, always optimize (or compress) your images before uploading your presentation to Blackboard. Optimization means you have made your pictures as small as possible (in terms of bytes) while still maintaining acceptable image quality and resolution
When excessively large PowerPoint files are placed on Blackboard, they are slow to upload and download and take up valuable storage space on our limited-capacity server. In addition, if your students download PowerPoint presentations all at once (for example at the beginning of a lecture), large files will seriously overburden the network, making downloading next to impossible. Optimizing your images in PowerPoint can reduce your file size by up to 75%.The Solution for Bloated Files
It’s always best to start with images that don’t have to be seriously re-sized, compressed, or cropped in PowerPoint. However, if you skip this step, PowerPoint 2007 has an easy-to-use Compress Images function. This function will delete the unused parts of your images and reduce resolution to a specified setting, leading to a significant overall reduction in your file size (see below).
Case 1: Professor Brown scaled down all her images in PowerPoint in order to make them fit in the slides better. She also realized that that many of her images included unnecessary background information, so she used the crop tool in PowerPoint to fix them. While her finished presentation looked great, her file size seemed unusually large (39.5 MB). This is because parts of the images (or pixels) she thought she eliminated were merely hidden - they still existed inside her file. By using Compress Images , Dr. Brown reduced her file size to 22.6 MB
Case 2: Professor Smith inserted numerous high resolution images from his 12 megapixel camera in his PowerPoint presentation. When he was finished, he had a hefty 57 MB file that took over an hour to upload to Blackboard from his home computer. The presentation was viewed by students on their home computers and shown in class on a projector. High resolution images are meant for print output only, so Dr. Smith’s PowerPoint presentation was unnecessarily large. By using Compress Images , he reduced his file size to an astonishing 7.2 MB.