How do you create a gradual transparency?

This might be a really obvious question, but I was wondering... If I was to have a rectangular object or something... how could I apply a gradient of sorts that makes it starts completely solid, but gradually becomes more and more transparent?

Thanks.

i'm pretty sure each layer can only have one transparency level...

Have you tried creating a layer mask with a gradient?

Ok. Load your image or copy it onto a transparant bg.

Then, go to channels pallet, create new channel.
Next, select the gradient tool(where the paintbucket is), and pick the gradient that goes from white to transparant.

Make sure your new channel is selected in the pallet. click the side of the image you want to be transparant(start about a 10th of the way away from the edge) and drag toward where you want it solid(end about 1/4th of the way away from that edge)

Go to layers pallet, click the layer with the image. Go to select/load selection. Then in the channel box, select Alpha1. Click OK

Hit Delete. Then, make a background layer that is white or whatever the background needs to be.

Any questions, just reply.

jagpunk: You seem to know your way around PS based on your detailed suggestion. My followup question would be...

I would have just suggested the same thing crsjr did. I would have simply created a layer mask and applied a gradient to get the desired result. It's editable, undo-able at a later time, and simple. Is there a reason you would go to the extra work of creating a channel to achieve what I'm assuming is a similar result, but not editable later? Please understand, I'm not calling you out; I really would like to know if the results are that much better one way or the other.

Thanks.

Yeah, I guess a layer mask is easier. Neither way is better as far as end results. I just have never done it using a mask personally.

One of the primary reasons for using channels in images is that the filesize is much smaller.

i have a basic tut on my site that might be of help to ya

http://www.heathrowe.com/tutorials.asp >> 'Image Blending'

touches on what malibu suggested
cheers
heathrowe