How can I change the brightness of only one layer in photoshop CS4 rather than the entire picture?

If you are asking about using an adjustment layer to only brighten one layer, you will need to make the adjustment layer into a Clipping Mask. I haven't used CS4, but in the previous versions, you select the adjustment layer in the layer palette, right click on it and select Make Clipping Mask. Or you can go to the Layer pulldown menu and Select Clipping Mask. Or alt+ctrl+G





Once you've done that - the adjustment layer should slide over and you'll see a little arrow pointing down to the layer beneath it - the layer that it is adjusting.How can I change the brightness of only one layer in photoshop CS4 rather than the entire picture?
you can do it several ways, change the occupancy of all the other layers lock all the other layers and brighten it, but the best way is to look through tutorials and take a few, they REALLY help you learn about the program in a very short amount of time. i can do all sorts of things now that i have taken a few tutorials. just google photoshop tutorial and just click on a few links, there are thousands. eventually you ca n use the program in real life situations.....here is a few i have done:





Logo:


http://www.megaupload.com/?d=U02EY9CL


penguin surfer:


http://www.megaupload.com/?d=XQJLMBP1


Professional restaurant design:


http://www.megaupload.com/?d=HU8U2G6IHow can I change the brightness of only one layer in photoshop CS4 rather than the entire picture?
you should be able to do this. If you look at your layer, you should have the ability to make it either Normal, or a host of other options like lighten, darken soft light harsh light etc.





I mean i'm working with photoshop 7, but the concepts are the same. Once you click on a certain layer, you can do just about anything to JUST that layer. Look for little drop down boxes and menus once you are in a certain layer.
If you have the layer you want selected, using image%26gt;adjustments%26gt;brightness and contrast should only affect that layer. However using an adjustment layer will affect any visible layer underneath it (unless you ';merge down'; rather than ';flatten';).
make an adjustment layer