I love using Curves because they’re so precise, but it’s easy to get your curves as messed up as an untended fishing line (if you’ve ever tried to untangle a fishing line, you’ll know what I mean). If you apply Curves as an adjustment (not an adjustment layer), or any other function that uses a dialog, perhaps you quit out of the dialog and relaunched it, nice and fresh. I have good news for you: You don’t have to do that, you can just hit the Reset button. But I hear you say, “I can’t find the Reset button.” This is one of those hidden features. If you hold down the Option (PC: Alt) key, the Cancel button will turn into a Reset button. Now, that’s handy!
Bonus Tip: If you apply Curves as an adjustment layer, you’ll find a handy reset button at the bottom of the Properties panel. It’s the icon of an underscored curved arrow.
This tip previously published in Colin Smith’s Photoshop Tips column, in the April, 2020 issue of Photoshop User magazine.