Software included for Lightroom photoshop....?

No, not needed. Your camera and Lightroom use the this card to set the correct WB. See http://youtu.be/UJRJ-n57h_c

Can a gray paint chip sample from Home depot do the same thing?

In short.... No. There are so many shades of gray that you don't really know what you are getting from a paint chip. The 18% gray reflective is created with a RGB balance that makes it neutral AND reflects 18% of the light that hits it. In the 'old film' world, light meters were calibrated for 18% gray. "By definition 18% gray is the “mid-point between black and white on a logarithmic or exponential curve.” Think of it this way; it is simply halfway between black and white. It is the average in terms of scene brightness and has for many years been the one constant thing that photographers use on which to base their exposures on."

What is the material of the cards? is it just think paper card stock?

Yes, it's basically stiff heavy GSM paper/card. (I ordered two at the time myself when I read others reviews for wear & tear purposes in case they were overly flimsy, so far they have survived.)

ASIN	B00AWT2QCE
Best Sellers Rank	#7 in Photographic Light Meter Color Calibration Charts
Customer Reviews	4.1 4.1 out of 5 stars (828)
Date First Available	January 4, 2013
Is Discontinued By Manufacturer	No
Item Weight	0.704 ounces
Item model number	FBA_DGK - DKK 5x7
Manufacturer	DGK Color Tools
Product Dimensions	6.8 x 0.12 x 9 inches

DKK 5" x 7" Set of 2 White Balance and Color Calibration Charts with 12% and 18% Gray - Includes Frame Stand and User Guide

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Specifications

Common Questions