background picture UNWANTED compression

[matus]

I need to save details in my background picture. If I put JPEG picture into
presentation, I can control quality (I use 220 dpi default for Printing). But
if I use the same picture in background, it is´s very compressed and I lose
details.
I have here one old ppt document and there is background in good quality.
But I can´t reproduce the same proces how it was created (not by me ). If
I use copy of this document and I put there the same or new background
picture, it´s allways compressed much more than I want.
I can control picture resolution, but I´m affraid it has no effect to
background pictures. (I use PowerPoint 2007)

 

[matus]

That´s nice with registry update (I used that other way File > Save As...
already before.) But I´m affraid this settings don´t affect background
picture I changed registry, I switched off automatic compression in new
file. But when I import jpeg into backgroud in new PPT file, it´s compressed
and blur. If I import the same picture like picture and not background, it´s
OK.
I installed old Office 2003: when I import JPEG into background, it´s OK
too.
But I hope there is some clever way how to use backgound pictures with
quality controlled by me and not by that stupid PowerPoint 2007