Change 32-bit Preview Options back to default?

I've been using Merge to HDR to make 32-bit images the past few days. It all went beautifully until yesterday when all of a sudden Photoshop started to display any newly created images very oddily (extreme gamma/exposure values). I've been able to pinpoint it to the View -> 32-bit Preview Options window, which has very erratic values.

So somehow Photoshop defaulted to very incorrect values for this window. Is there any way to change the default values or reset this menu option?

I don't really want to trash preferences as I may lose other important customizations that I made :-(

What other "Important" customizations would you lose?

So long as you make sure not to ditch custom brush sets, shapes, styles, and other presets, resetting prefs is no big deal. It's always a good idea to have all of your custom stuff backed up somewhere anyway, so you reload them at will should a serious hard drive disaster occur.