Then you have no need to set a custom WB in camera unless you find it helps you taking the photos. The camera WB setting does not effect raw files. For raw files WB is set during raw conversion. To set an accurate WB for your subject shoot a WB target. You can buy one (http://whibal.com) or as previously noted a piece of white Styrofoam is ideal. A grey card may work but they tend to yellow with age -- I'd just buy a cup of coffee from the gas station that sells it in Styrofoam cups.

A convenience of managing WB with raw files is that you don't have to shoot the target first. In the illustration below you see some recent photos I took of my wife's fothergilla. The last photo is a shot of the WB target which in my case is just a piece of a Styrofoam food tray that I've inserted into the photo. To process the photos I first go to the shot with the target and read the target with the WB eyedropper. Then I copy that value and paste it to the other photos. You can of course still change the WB to taste but setting from the target first starts you off from an accurate position.

If the lighting changes while you're working shoot the target for each condition.

I've read about this numerous times and think one has to view the image on the LCD screen/EVF and manipulate colors to meet what one's brain considers "neutral grey." Having defective color vision (red/green + something else) leaves me unable to complete this task successfully. Seems obvious I must rely on "Auto WB' or just keep it on "Daylight" which is what I've been doing. As Gary Friedman tells it:

How to Nail the White Balance using the Grey Card
· Do one of the following:
o With the subject holding the card in front of them, do a Custom White Balance in your camera. The white balance will be locked until you change it.
o When you’re processing your images on your computer, use the test shot taken in Step 1. Use the White Balance Selector tool (commonly referred to as the “Eyedropper Tool”) on the grey card to set the white balance, then apply that setting to all the images in that session.
· That’s it!

BTW, I noticed years ago that my eyes each have slightly different ideas of the colors I'm seeing. I wonder how many other folks have such, seems about right since bilateral symmetry is typically off a smidge naturally.

I ask this because I keep hoping the answer involves a button that will magically find and set the "correct" WB but suspect that's what I'm already doing with "daylight."

I have noticed that PSE & LR sometimes/rather often select a "auto WB correction" that even I can see is wayyy off. My guess is that when one color predominates as green in a lush landscape the auto algorithm takes too much green out leaving other colors off kilter.

Here I go ignoring Mark Twain's good advice; "It's better to keep your mouth shut and appear stupid than open it and remove all doubt.”

Setting a white balance seems to be a personal choice. Some say use the auto, others say only if you shoot jpeg and some have said use a gray card.

Several years ago I worked for a school photography company, we shot jpeg and we were to do a custom white balance before each and every job. Our procedure was to set up the lights and camera, double check all the settings and then shoot a "white balance card." That was a card consisting of four triangles with their apices at the center. In landscape orientation there was a black triangle at the left, a white triangle at the right and a middle gray triangle at the top and bottom of the card. The company used Canon cameras which had a custom white balance setting in the menus indicated by an icon of a rectangle sitting on two wedges. .I currently use a Pentax K-70 which has a similar icon to denote the menu for setting it. The card was set in the subject position and a photo taken. the histogram was to appear with three high points, gray in the middle with black and white at the edges. the black and white points were to be equidistant from their respective end meaning the lights were not over or under bright. If they were not equal, we adjusted the lighting accordingly and reshot the test photo. That sounds like a long process but it really was not very difficult and the colors were very good. The upside of this process, it does not require perfect color vision, simply evaluation of the histogram in black, white and gray.

I've read about this numerous times and think one has to view the image on the LCD screen/EVF and manipulate colors to meet what one's brain considers "neutral grey." Having defective color vision (red/green + something else) leaves me unable to complete this task successfully. Seems obvious I must rely on "Auto WB' or just keep it on "Daylight" which is what I've been doing. As Gary Friedman tells it:

How to Nail the White Balance using the Grey Card
· Do one of the following:
o With the subject holding the card in front of them, do a Custom White Balance in your camera. The white balance will be locked until you change it.
o When you’re processing your images on your computer, use the test shot taken in Step 1. Use the White Balance Selector tool (commonly referred to as the “Eyedropper Tool”) on the grey card to set the white balance, then apply that setting to all the images in that session.
· That’s it!

BTW, I noticed years ago that my eyes each have slightly different ideas of the colors I'm seeing. I wonder how many other folks have such, seems about right since bilateral symmetry is typically off a smidge naturally.

I ask this because I keep hoping the answer involves a button that will magically find and set the "correct" WB but suspect that's what I'm already doing with "daylight."

I have noticed that PSE & LR sometimes/rather often select a "auto WB correction" that even I can see is wayyy off. My guess is that when one color predominates as green in a lush landscape the auto algorithm takes too much green out leaving other colors off kilter.

Here I go ignoring Mark Twain's good advice; "It's better to keep your mouth shut and appear stupid than open it and remove all doubt.”