Written by Shas'El Tael (additional Square Lens by Ultrablue42)
The following is a simple technique I use for my lens work. Basically, my aim is to choose a base colour, two highlights and white. No mixing. Makes for very straight forward and bold lens work. Perfect for production line work of an entire squad.
As per your colour preference. Essentially, choose a dark base, medium highlight and a sharp highlight then white.
Fine Detail Brush
(I use different brushes with size numbers, but I'm using Games Workshop's system for reference)
The Sequence :
I like to have a dark color ring (black even) or shaded background to the lens area, makes the lens Pop! off the miniature and not get lost in the details.
You can further advance this technique with a shade wash over the highlights to tone down the brightness of the lense. Also, choosing a very bright shade of the lense colour as the 'light spot' can add a soft depth to the 'gem' effect.
I hope this quick tutorial helped those whom asked