Tween: motion: scale Question

I am scaling (zooming in/out) images for a photo slideshow in flash.

The images are jpegs and I am scaling them 5% over 75 frames with a 12 fps frame rate.

The images are looking degraded as they scale up and down.

Is there any way to smoothly scale bitmap images in flash or should I use a different program/technique?

Thanks for your help.
Aryon