On a surprisingly regular basis, I get requests from users who want to send Powerpoint-presentations via email, but are stopped because the presentations are too big. 30 MB isn’t uncommon, and just the other day, I had someone with a presentation of a whopping 75 MB.
The main culprit behind the issue they are seeing, is the fact that they include many high resolution images. The reasoning is that high quality pictures result in ease of interpreting the images when the presentation is given. This reasoning, though understandable, displays a lack of understanding of the limitations posed by projectors. These usually offer a resolution of no more than 1280×800 pixels, and many older models only support 800×600 pixels. With that in mind, low resolution images will serve the presenter nicely. In addition, the default resolution of a Powerpoint presentation is 1024 x 768 pixels at 96dpi.
So, while it would be preferable if they had used lo-res images in the first place, you can compress them after the fact. Here’s how:
- Click a picture that you want to compress
- In the Format Picture tab, click Compress
- Select the preferred quality in the drop-down menu (220 ppi for print, 150 ppi for presentations, or 96 ppi for email)
- Select whether to apply the change to all pictures, or just the one currently chosen
That done, Powerpoint will take a little while to perform the changes.