Photoshop :: Channels Work Will Not Show In...

I have Windows Vista, 4 megs RAM 2.4 gig quad core processor. I have been using CS3 and before that Photoshop 7 so I am fairly familiar with the navigator window. When you open a picture it also appears in the navigator window. As you perform an action(s) you see it copied in the navigator window. I opened a picture and opened the channels window. that is where you see RGB , red, blue and green channels. As you work with these such as removing a channel your picture changes appearance due to the absence of that color. The picture in the viewing window changes. The picture in the navigator window remains UNchanged. When I click save or save as the picture is saved WITHout the modifications performed with the channel selector. Example, i opened a pic, removed RGB, blue and red channels leaving only the green channel. I increased the contrast to 100%. This approximates an infrared image. I chose "save as" and named the picture. The picture was saved without any of the mods performed. Of course as stated they were never visible in the navigator. I take the same picture and paint a big red stripe on it and the red stripa also is shown in the navigator and I am able to save the red striped picture. Further, I did or at least thought that I saved one pic using the above channel scenario.