Testing Lighting and Shading

I'm working on a simplified ray tracer. Up to know, I've managed to light up spheres. I am currently implementing a shading model. When the image pops up, I see some shadows which seem legit but I'm not sure. Is there a program/software/website where I can set objects and lights data (such as origin, colour, size) and compare my result with an image that would turn out to be an accurate one ? As for now, the only thing I can check if it's accurate is the colour outputted by my program.