Gradients and contrast adjustment

Dear Advanced photoshop users,

I think I remember from the dim and distant past that it is possible to use layers and gradients to change the contrast of an image selectively, but I can't remember how. E.g. if an image needs the contrast increased only on the left hand sided and by a graduated amount from l to r?
Is the this true or is my memory failng?

Thanks

Tony

u mean like this?

Exactly! How did you do it?

Tony

you could make a new adjustment layer, and fiddle with that, and then make a mask, or just make a selection which is half of the imageSize, then feather it by a lot of pixels, and hit DEL.

I actually used the gradient tool on a layer above the original pic. It went from foreground color(black) to transparent.

yeah but that would block anything behind it if you wanted something to show through. Layer Masking works good.

Once you apply the gradient to the layer, what next to apply the prtial change in contrast to the image beneath?

Tony