You cannot switch paper profiles willy-nilly. You must use a target profile that has been generated specifically for your particular combination of ink/paper/printer. Anything other than that will not give you good results.
What you are describing is perfectly normal, expected behavior. Of course you can see your image "die" before your eyes when you're soft proofing. There is no combination of paper and ink on this planet that can reproduce the brightness, luminosity and vibrancy of a computer screen.
That's where soft proofing comes to the rescue. While you are still in soft-proof view mode, you can develop an adjustment, most likely a Curves adjustment layer, that will give you optimal results for that particular combination of paper and ink every time. Any adjustment that helps you is valid. I find that a Curves adjustment with a gently S-shaped curve works wonders, and I have saved a large number of Curves presets for each combination of paper and ink I use often.
Others like to use a Brightness/Contrast adjustment layer, or a Vibrancy adjustment layer, even a combination of such layers.
If you have a high-end printer, some of the priciest models can generate custom profiles for your particular printer unit. There are commercial services that can generate a custom profile for your particular printer (any printer) and paper by having you print a target file and snail-mailing it to them to be analyzed with a spectrometer/colorimeter and they email you back the custom profile.
Even then, a final adjustment layer may be required.
Very helpful. Along those lines, often when I soft proof, make adjustment, and am satisfied, going to print preview makes it look quite different again. Any reason this should be the case?
It all depends on your print settings not only in Photoshop but also in the Printer driver settings too. Can you post screen shots of all the pertinent dialog boxes?
Of course, everything is predicated on an accurately calibrated and profiled monitor. Calibrate and profile your monitor regularly and often.
Please state the exact version number of Photoshop and of your OS.
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