Creating a photo image within text

So I've created some text on one layer and I have a photo image on another layer. How do I make a layer that is comprised of the photo image within the text?

Cheers in advance.

I'm not sure what you mean...

but I think you can get your effect like this.
Go to your photo layer, ctrl + a... ctrl + c

Then ctrl + click your text layer... go to edit --> paste inside or something.

For example I have the word TREES written on one layer and I have a photo of a some trees on another layer. So instead of having the text floating over the top of the photo I want to be able to see the trees within the actual text characters. I don't want to be able to see the trees outside of the individual text characters. Hope this clarifies what I mean.

Create a pattern out of the tree pic and use it to fill the type. You may have to rasterize the type first.