PS Curves Issue

Hey Guys,
Having a slight problem with my CS4
when I raise my curve its darkening the image instead of lightening it.

Pulled up the image in CS5 and it works the way it should. However graphically, the histogram seems like it is reversed in CS4.

Is its a setting you can fix within photoshop?

thanks.

***NOW FIXED*** Thread Closed - Somehow cannot delete the thread.

PM a Mod...or, click the little Report button on the lower part of the left panel of your post (the little exclamation mark).

We do not usually delete threads unless the violate the rules. Others may experience the same problems so these threads remain available for all to learn.

There's no need to delete the thread. Why not post your solution so somebody else can learn?

For the record, there are some little tiny arrows in the middle of the bottom of the curve that switch it around.

There was an option that allowed you to reverse the curves action available in/on the curves layer which you accidentally activated, unfortunately that's all I remember, sorry.

I have had this happen a few times in Cs2 also. I think a reboot fixed it, not sure .... been to long.

CS4 Curves adjustment layer: