I know I've seen this done many times but for the life of me I cant figure out how to reproduce it! Its a photograph where the head/torso was cut out and faded to a 100% transparency at a 45 degree angle (so the image faded into the background... could anyone enlighten me as to how to accomplish this? thanks!

I'm not sure I understand. Do you have a sample?

this is what I'm looking to do (I have to put the picture on a different background in illustrator

The headshot will need to be on its own layer, masked out or cut out so there's no background. The background that you actually want to use will be on its own layer beneath that layer.

Then, on the headshot layer, create a layer mask -- you can do this via one of the icons in the layers palette or via the menu under Layer. Make the layer mask active (dotted white circle on gray background will be next to the eye on the layer), then use the gradient tool to put a wash of white fading to black. Where the layer mask is white, your headshot will show. Where the layer mask is black, it will be transparent. The grays between will make it fade.

If you want to control where the fade is, you can simply use the airbrush to edit the layer mask with various shades of gray.

the head layer can be duplicated,, layer via copy.  select all the background layer - delete - fill it with... green.  select the head layer and use aprilgem's tip ---  view the layers pallete   then clik on, then drag the 'layer mask'  (the one on the right )  to the little bin and click apply.

ta da.. i hope.

maybe you can drag that layer over to the illustrator document and scale to size...

or just have the pic on a new layer, and use a really diffuse eraser brush to erase the unwanted bits...

or just make a new layer above the pic, have a colour to transparent gradient on it. ctrl-click on the layer icon to select all and then change back to the picture layer and delete, then trash the gradient layer.

saves all that mucking around with layer masks etc

Quote - saves all that mucking around with layer masks etc

Erasing DOES save you the trouble of dealing with layer masks. However, the problem with NOT using a layer mask and with erasing instead ... is that once you've erased pixel information, you can't get it back.

Quote - is that once you've erased pixel information, you can't get it back.

that's what the history/step back feature is for....?

Quote - > Quote - is that once you've erased pixel information, you can't get it back.

 

that's what the history/step back feature is for....?

Yes, but very rarely can the history go back that far -- I set mine low for a speedier workflow, and I usually do a whole lot more to a file than just a simple fade. Plus, after you save a file and get out of it, the history's no longer there anyway. I deal with finicky clients who ask for impossible changes, so whenever I can achieve an affect without losing out on original information, I do it ... because it would be just my luck that they ask for a change that requires me to, say, make the fade more/less gradual; so if I erase information in the first place, I'd end up having to do the entire file all over again, whereas if I use a layer mask at the start, all I have to do is tweak that mask, and I'm good to go on the second draft.

So ... I use a layer mask rather than erase. There's always a VERY good reason for the way I do things, and that reason is I'm lazy and don't want to do extra work later. ;)

"history" (no pun intended) has shown us that non-destructive methods (masking) tend to allow a "change-of-heart" in the future rather than a "start-over-with-a-fresh-copy" if you find you wanted something back.
:)
retrocity

What retrocity said. :)