Images Appear Different When Viewed in Photoshop CS4 vs. LR 2.7

Question

Hello, I hope someone on this forum can help.
I have a series of high quality images that are catalogued using Lightroom 2.7.  Many were edited using Photoshop while others were edited in the "Develop" module of Lightroom.  All of the images look exceptional in both Lightroom and Brdige.  However, when I open some of the images in PS, either directly from Bridge or by using the "Edit in" command from Lightroom, they appear washed out and dull -- very different and much worse.  I always use the setting, "Edit a Copy with Lightroom Adjustments."  The problem pertains to all images regardless of file format (JPEG, DNG, NEF, etc.) and regardless of whether they are opened from LR, Bridge or directly from the image using the "Open with" command in Windows.
This happens on two completely different set of monitors.  At work I have a Dell 2208 WFPt UltraSharp monitor, and at home a dual monitor setup with an Asus VE278Q and an LG flat screen (all are flat screen, high quality monitors).  I have a Lenovo X201s with 8gb of RAM and a high-speed i7 processor running Windows 7, 64-bit.  All of my Adobe products are up-to-date.  Windows Color Management shows all displays as "Generic PnP Monitor - Intel HD Graphics," and the Advanced mode of Intel's HD Graphics correctly identifies each monitor being used.  The problem is identical regardless of which monitor is being used and it does not seem to make any difference as to which color profile is associated with the monitor (I have two profiles added -- Adobe RGB (1998) (the default) and sRGB IEC61966-2.1).
Specifically, if I double-click on a particular TIF image in Bridge (where the preview looks great), it then triggers Camera Raw 5.7 - TIF, where again the image looks terrific.  The settings applied by Camera Raw are "ProPhotoRGB; 16 bit; 3607 by 2420 (8.7MP); 300 ppi" (although changing these settings makes no difference whatever when the image is subsequently opened in Photoshop).  When the image is opened in Photoshop it looks terrible -- dull and washed out.  I encounter the exact same problem when using my dual monitor setup at home, so I don't think monitor calibrations are the cause.
Strangely, I don't think this problem existed a couple of months ago.  I've been busy on a project and haven't used Photoshop since the end of this past July (of 2011).  As I recall, this problem did not exist then, so I'm wondering if a setting in Photoshop inadvertently got altered since then.
I have the following key settings in Photoshop's "Color Settings":
Working Spaces: RGB -- ProPhoto RGB
Color Management Policies -- Preserve Embedded Profiles
Conversion Options -- Adobe (ACE)
I have the following key settings in Lightroom's "Preferences / External Editing":
Edit in Adobe Photoshop CS4
File Format -- PSD; Color Space ProPhoto RGB, 16-bits, 300 dpi
File Format -- TIFF; Color Space ProPhoto RGB, 16-bits, 300 dpi
I have tried and tried to figure this out, to no avail.  Any help would be greatly appreciated!
Bob Woods
St. Paul, Minnesota

Answer 1

Thanks, I think you're right.
Any suggestions for a cheap and easy way to calibrate my monitors?