24 Color Card Test for Digital Color Correction
As I saw in one of Keifer Hunniford video, he uses XRite Color Checker Passport. I agree, it can be a great idea for a professional photographers, but I'm not that level, therefore, I need a cheap solution.
As I checked on ebay, I found a 24 color card solution, the cost is less than 20$. I ordered one of them, and I also developed a software version of the Card.