White Balance using Nikon 7100 and SB700 Speedlight using a grey card

Hi,
I just started using my SB700 flash more in shooting interiors of homes for real estate. I currently white balance all of my bracketed photos. The color is not just right and I feel it is the flash white balance. I want to use a grey card. I saw great Youtube video but cannot find it. Can someone explain the step please.
Thank you.
Ron

What software are you using to do your post processing?

Adobe Camera RAW, for instance, has a White Balance tool that would use the grey card in your photo.
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Welcome to the site.

If you are selecting the preset flash white balance in camera you may be correct. Another thing to consider adding flash to a scene changes the scene by introducing a different color of light, especially indoors. The camera sees this but you won't because of the speed of the flash. If the flash is gelled to match the color of the light in the room this will reduce this effect allowing the ambiance to remain the same.

If you are looking for how to set a custom balance in camera it starts on page 95 of the D7100 manual.

If you pick through this thread there is some good information.

http://nikonites.com/photography-q-and-a/31648-do-you-use-white-balance.html?highlight=white+balance