dimming an image

[dumainew]

When I've finished preparing an image and leave it alone for a little while, the screen dims. It's an imac- and it's part of the energy saving mode. When dimmed the image looks soft and sometimes nearly dreamlike. It's a subtle darkening. I've tried to imitate the look by playing with levels, curves, luminosity, and other controls in PS5. But I can't quite get the same effect the dimming of the monitor achieves. Does anyone know how to do this ?
Thanks for reading.

[stamper]

One possibility is a saturation boost with a Gaussian blur. You would need to experiment with the amounts in both.

[Slobodan Blagojevic]

With Curves, try moving the extreme points up or down, ie, (0,0) up and (255,255) down. Usually, we leave those anchored, while we adjust shadows/highlights up or down.

[Pete Berry]

I've found bringing the image back into ACR and applying considerable negative Clarity gives a dreamy effect, as in the attached image from a series on Bodie interiors through the old windows. And I used the adjustment brush to simply reverse the effect in the square area above the table top.

Pete

[dhancock]

I sometimes use a plugin called wavelet decompose on GIMP. It is meant for portrait editing, as it breaks down the photograph into a color layer and then various levels of detail layers. However, I've found that if you remove certain detail layers, it creates cool dreamy effects. I'm guessing there is a PS equivalent?