Question on Color Correction / gamma

I'm correcting footage shot with a "flat" camera style. When I correct the footage using SA Color Finesse in AE, I feel like I'm pretty clear on using the HSL controls - except for gamma. My goal is to set Pedestal to crush the blacks a bit around 0 and Gain to bring the brightest white point toward 100. But Gamma is throwing me and making my footage look inconsistent I think. Is there a proper way to work with these controls? What if you have footage where there's no real black or white? Thanks!