PowerPoint 2003/2007 圖像的輸出預設的解析度為96dpi, 這對一般的使用者來說其實已經相當足夠, 但我們有時候在一些研討會或印刷用途, 需要到300dpi的解析度, 這時候就需要從作業系統的REGISTRY去做修改了.

1. Select Run from the Start menu.
2. Type regedit into the Run box, and then click OK.
3. Once the Registry Editor has opened, navigate your way to the registry key for PowerPoint. This will depend on which version of PowerPoint you are using.

PowerPoint 2003: HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\PowerPoint\Options

PowerPoint 2007: HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\PowerPoint\Options

4. Select Options by clicking on it once, and then click the Edit menu, then New and then DWORD Value.
5. Type ExportBitmapResolution, and then press ENTER.
6. Select ExportBitmapResolution, and click on Modify on the Edit menu.
7. In the Value data box, type your desired resolution value: 300, then click Decimal (the value will change to 768), and then click OK.
8. Exit the Registry Editor.

Saving a high resolution image in PowerPoint
To save an image, you simply export a PowerPoint slide as a picture.
1. Have the slide that you want to export open.
2. Select Save As from the File menu.
3. In the Save as dialog, select the type of file that you want to export your slide as (.gif, .jpg, .png, .tif, .bmp, .wmf or .emf), and then click Save.

參考文章: http://markantoniou.blogspot.com/2009/11/create-high-resolution-300dpi-images.html