I can't persuade Photoshop CS4 to remember the display mode (colour channels). If I have several images open and chnage the setting to Luminosity it sticks as I switch from image to image, but once all are closed and I open a new set of images it goes back to showing the (RGB in this case) colour channels as three coloured curves. Since I want the panel compact this is a pain as it takes multiple clicks to expand, chnage option, and compact. Is there a trick to this? If not, is it a bug or a feature-choice by the designers?