I haven't seen any one-stop fix all for underwater photos with PSP X, but I also haven't really looked that hard. With PSP X, I have tended to run down the Enhance Photo dropdown. Don't use the one step photo fix, that's very unlikely to give you the best result. I'll start with the smart photo fix, and just run down the subsequent menu choices. That will cover exposure, color balance, sharpness, and noise. For color balance, keep in mind that the smart select is not necessarily going to be the best, you need to choose something where you know what it's color should be and use that. Adjust from there, and cross your fingers. At the end of the enhance photo dropdown, I accept that over 50% of the photos I take are crap, and nothing is going to save them. You can use the clone brushes to get rid of particles, and I had some good luck with the fade correction tool after doing color balance, but generally if your photo isn't up to snuff after the enhance photo choices, it's probably because it's just not a good photo to begin with. If you're going to take a lot of time with it in PSP X, it had better be a real one of a kind picture, or at least pictures from someplace you don't expect to visit anytime soon - if it's not, just go dive with your camera again, and learn from your previous attempt. Don't take that to mean you should just delete a poorly exposed but in focus photo; you may just need to wait for some high-end photo software processing or a brand new processing tool to make its way into the lower end tools. I've managed to get some decent results out of shots that had no manual white balance or strobe, but it did take almost 3 years to have software that was good enough to do so without massive amounts of effort.
In PSP X, skip the clarify choice. They screwed it up between IX and X, not that it seemed to do much in IX. Now that PSP took a clue from Spinal Tap and goes to eleven, you could try getting the newest version and see if it's better on color balance. At this point, I am using Adobe Lightroom to process most things, PSP X is still around for a few specialized options like lens distortion (I'm not one for taking a lot of time using the clone brush or other things, I'd rather go dive again and not get the smutz in the photo). Once Lightroom goes gold, I'll decide on upgrading to PSP XI or buying Lightroom. I think Lightroom is better for color balance and exposure adjustments, but it doesn't offer much for image editing. Also, PSP X can't read my Rebel XTi raw photos (although the specs indicate XI can, but that's not an underwater thing yet). If you are taking raw photos, consider using the Pixmantec Rawshooter Essentials that you should have been able to download and install with the purchase of PSP X, it is also much better for color balancing. Lightroom and Pixmantec allow you to export to JPEG if you want to do further editing in PSP X with the airbrush or cloning brushes.
