Hi Barry,

No, not really.

The disks are there to "stop down" if needed while retaining the soft effect. Using the aperture blades to stop down reduces the soft effect much more and by f8 it's gone and the lens works like a normal sharp focus lens.

Knowing that the disks preserve the effect as much as possible and that the aperture blades diminish the effect can help you control the end result for a given shot.

I bought myself a rangefinder screen to focus with and that helped me a bunch to help get the eyes sharp because it is tougher to focus.