Slideshow screensaver too fast.

[Glenn.eu]

Is there any way to slow down the slideshow from the screensaver?
I know i can put in a timer when manually starting a slideshow in iPhoto but i would like to change the time between pictures in the screensaver.

Thanks in advance!

 

[Litho]

I agree the photos change every 5-6 sec and I wanted them to change every 30 sec if not longer