Layers Question in PS 5.5

Hello,



Hope this is the right forum. Simple question:



I create a new file with a white background. Next I open a digital color image. I select and move a portion of the digital image onto the first, white layer. I transform the image. I select the image layer and apply a gradient to the image layer and it covers the entire canvas, which I do not want.



How do I apply filters only to the image layer? I want the original background to act as a frame.



Thanks.
Layers Question in PS 5.5
Lock transparency (small icon next to layer in palette).



(Note, this is not an SDK-related question. If you had posted in the main Photoshop forum you'd have 99 answers by now :-)
Layers Question in PS 5.5
Thanks Toby, this works fine.