Start preparing your kneaded eraser. Take it and place it between your index finger and thumb, play with it for a while. This will work it in and will make it much stickier and will let you pull much more graphite. Again take the kneaded eraser and place it between your index finger and thumb and squeeze. This will give an edge to the eraser. With this edge you will be puling highlights around the iris. You will be following the guidelines that you added before. You blended them but some of them should still be visible. Go around the iris in a tapping motion, you will probably have to remake the edge with each tap, doing this will give you really sharp lines.
On this step you will be adding shadows on the edge of the iris, since there is lots of black outside of the iris, you will be blending this into the iris. You will do this mostly on the left side, top and bottom of iris. The shadow will be more significant at the top and left side of iris. You will also darken the outline of the shape around the pupil, this will give the whole iris much more depth. Blend that darker area with the iris by pulling from the darkness out, again this will make more shadows. Slowly you can start to see how layering can bring a drawing to life. It might take longer but the results are always great.
Here we will darken the left side and will darken some of the shadows on the right side. Take your 2h pencil and lightly go over the left side of the iris, this will evenly darken the light areas and the dark areas. Take your mechanical pencil and start adding darker shadows on the right side. Add these shadows randomly under certain highlights, don’t make them too dark, just enough for the highlight to jump out.
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