Quick Question: Photovision and Other Grey Cards

I have searched and I have not found a definitive answer.
With a photovision or grey card, I first you it to create a custom WB to use, then I pick that Custom WB and then I take pictures of the card to get the correct exposure by adjusting exposure until I have three spikes in the histogram.
Is this the correct process?
Any other advice?

No need to do any custom WB. At least not if you're shooting RAW.

Simply shoot the card in the light you intend to use, then eye dropper it when you edit your images and apply that WB value accross the board.

Didnt your photovision come with the DVD? That video is a great instructional DVD on how to use their product. All you should have to do however is shoot the disc then set the custom WB in your camera and youre done.

I didnt get one yet, but im looking into it and was wondering about how to use it.

bimmeracer3 wrote in post #6233301
I didnt get one yet, but im looking into it and was wondering about how to use it.

Oh yea, get one, they are awesome! I have the 14" and recommend either that one or the 24" one. Dont worry, the DVD is really very good and will explain everything.

thats good to know about the DVD. Do you guys consider the $40-50 difference worth it for the photovision set over a regular grey card?

I have both and I like that the photovision has the 18% grey as well as the white and black sections. For setting levels in photoshop its very useful, thats what I got it for.

Im going to pick up a photovision set tomorrow.
My last question is, will the 6" disk be large enough to get accurate readings?