I have seen certain icons have very light, black shadow. It looks so real. I tried drawing a circle and playing with opacity. It never looked the way I wanted it to be. That is close to the original. How to make a realistic shadow to an element ? Thanks.

For specific steps, we would need to see an example of what you're talking about.

Assuming you mean a drop shadow, in general, I would:

- duplicate the object
- color either black, or make the existing color very dark
- move it below in z order
- move it down either by dragging or arrow keys
- give it some blur.

Or there's a drop shadow filter which it quite easy to use.

Drop shadow filter works well. Thanks