Hi! I'm planning to add to my site some product which user can interactively rotate and I'd like to add an opportunity for the user to choose paint colours of it. Instead of rendering a huge amount of images for each color, I want to do the same as it has been done on Renault official site. Here is .psd file attached with an image from here. As you can see this transparency got all shadow, reflection and specular information, so if you add some colour under the layer with the car you can change the colour of it and it looks great.
The image was taken from Renault official site. It is used with an interactive web configurator. Does anybody know how to prepare the same thing in Keyshot and Photoshop? Thanks!