I Know its been posted before but Color mismatch between lightroom and photoshop.

Mac: Dual monitor issues in photoshop

Here is my (temporary) workaround for MacBook and iMac users:

Set both Display screens to use the master display profile (normally the external display) in the System preferences / color pane - that fixes many dual screen appearance issues, but of course the MacBook or iMac screen is now inaccurate. so it's only a workaround 'til Adobe and Apple can fix this issue. 

Setting your MacBook or iMac (in system preferences displays/color to use the external display profile), it not destructive, you can easily switch back

Open System Preferences: Displays/color

see the icon there - at the left of row 2?

Click it.

SCREENSHOT:

You'll now see 2  dialog boxes, one (normally) appears on each screen, if you set each to the 'color' tab, they'll show the selected display screen ICC profile for that screen along with a list of others that are available.

[you may need to uncheck "show profiles for this display only"]

Simply check the name of the profile that’s being used on the external display in the dropdown list and select that from the list on your MacBook. 

Done.

You may need to restart Photoshop.

To change the MacBook back, should you wish to, perhaps for stand alone use, simply select the original display screen ICC profile again on the MacBook or iMac - it's probably called "colorLCD"

I have a few test profiles here in the screen-shot below, ignore those, you also can see the original "color LCD", that’s a display screen ICC profile that Apple made automatically for my Macbook

SCREENSHOT:

:: CALIBRATION & PROFILING OF YOUR SYSTEM::

IF you are doing any serious imaging work and would like to see continuity of appearance between your system and others, such as a print service - or even your own printer - then your main working display really does need to be calibrated & profiled.

For that you'll need a sensor such as the X-Rite i1display pro (better than Spyder).

Also you'll need good software, benQ do include the problematic Palette Master, with which a lot of users have serious issues trying to calibrate their screens.

In this case, I highly recommend basICColor display v6 calibration & profiling software -  

and be sure to select v2 ICC profiles. as they seem more universally acceptable

more here https://www.colourmanagement.net/products/basiccolor/basiccolor-display-software/

With any calibration you need to be sure that the achieved result is accurate, my belief is that the only way to achieve that is by using an unequivocal reference, a physical reference item. For this I use http://www.colourmanagement.net/products/icc-profile-verification-kit

Here is more discussion:

images color changing on external monitor and MBP

https://community.adobe.com/t5/photoshop/images-color-changing-on-external-monitor-and-mbp/m-p/11812719#M510463

Inconsistent color display on external monitors, Photoshop v 22.1.1 and Bridge v 11.0.1, Mac

https://community.adobe.com/t5/photoshop/inconsistent-color-display-on-external-monitors-photoshop-v-22-1-1-and-bridge-v-11-0-1-mac/m-p/11832114#M512962

I hope this helps
neil barstow, colourmanagement net :: adobe forum volunteer
google me "neil barstow colourmanagement" for lots of free articles on colour management
[please only use the blue reply button at the top of the page, this maintains the original thread title and chronological order of posts]

This is an issue that has been reported quite a few times lately, from users with iMac/MBP + an external display. The common factor and smoking gun is integrated display + external connected display.

What actually happens is that the wrong monitor profile is used for one or both displays, and yes, switching main and secondary display in the OS often gets around it.

It has never been reported from desktop systems with multiple connected displays. It has previously been seen with some Windows laptops as well, but always with the same integrated+external display configuration.

So this points quite clearly to a problem with display assignment in the video card/operating system. Photoshop normally has no influence on the monitor profile - it just uses whatever it gets from the operating system.

Are you comparing the colors in LR using Develop module at 1:1 or greater (then in Photoshop at 100%)?

You must. The other modules do not preview color and tone like Develop. 

IF there is a mismatch between Develop at 1:1 and Photoshop at 100%, then let's continue as it could be your GPU settings or a display profile issue.