Is it possible to change the opacity on a background image?

[Kibagami Jubei]

I know how to lower the opacity on images but what I want to know is if you can do this for a background image.

Pretty much I have this background image I want to add, but I still want the background under the background image to be seen. Is this possible?

[Laslett]

yes but I forgot what its called in Dreamweaver. go to the page properties bit and theres a slider thing