Blur filter demo:

[cq_magnify url="path/to/the/image.jpg" radius="80" bordercolor="rgba(255,255,255,0.8)" bordersize="12" moveby="press" x="240" y="180" width="640" filter="blur" title="" alt="" /]

Grayscale filter demo, change the moveby mode to hover, set the glass border to 1 only too:

[cq_magnify url="path/to/the/image.jpg" radius="80" bordercolor="rgba(0,0,0,.8)" bordersize="4" moveby="hover" x="360" y="240" width="640" filter="gray" title="" alt="" /]

Nice design from Fernando

Still demo, disable the magnifier move: