Hey Ken,
It does appear that the resolutions are not the same when exporting versus importing. We've reported this to development. Here are some things we found with testing:
Using the same 4:3 PowerPoint file, I exported it from PPT and used out Import utility. Oddly enough, the images we create are much a larger file size, but a lower resolution than what is produce by PowerPoint.
Both are produced at 96dpi
We produce at a bit depth of 32 and PPT is 24.
Our resolution is 720x540, PPT is 960x720
Total file size of all slides we created was 3.91MB, PPT was less than 1MB(.98)
What I found more interesting was, using the same PowerPoint saved in a 16:9 format, produced a smaller total file size exporting from PPT and Importing in MS.
Both are produced at 96dpi
We produce at a bit depth of 32 and PPT is 24.
Our resolution is 720x405, PPT is 960x540
Total file size of all slides we created was 3.03MB, PPT was 899KB
If you modify the registry, you can increase the export resolution from PPT. The link below are to those instructions.
https://support.microsoft.com/en-us/help/827745/how-to-change-the-export-resolution-of-a-powerpoint-slide
I've also had great success exporting from PowerPoint as PNG (instead of JPEG) to get a higher quality image, too. We will see what we can find out. Thanks!