> Quote - >     4) Postwork gamma correction - commonly done with the middle value in Photoshop "levels" dialog. Since this also causes hue/saturation shifts, it is usually followed by a hue/saturation adjustment,

 

A quick tip for those who are doing postwork gamma correction in Photoshop:  To prevent hue/saturation shifts while using levels or curves, set the Adjustment Layer blend mode to Luminosity.