bobschell

<p>All you need is a camera with manual mode and a 'bulb' setting. Set manual focus at infinity, use ISO 100, f/11-16. Hold your hat in front of the lens. Press & hold down shutter button, removing and replacing hat when you like the pattern of light. Finally, release the button to close the shutter. That's the easy part. The hardest thing is framing the composition.</p>

<p>This points out that many adapters are not as precise as they should be. De-centering & lack of parallelism are serious issues with wide angle RF lenses. I have had this problem with the Fotodiox 'Pro' adapter, which is non-adjustable. Voigtlander lenses are easy to fix. Simply loosen the 4 set screws on the rear of the lens and rotate the mounting ring 180 degrees.</p>

<p>I have had similar problems with my CV 25mm f/4 (ltm-nex). Switching from cheaper adapters with set screws to the Photodiox Pro adapter (a solid block of aluminum) improved results greatly. Digital sensors combined with wide angle RF lenses are extremely unforgiving of mis-alignment and lens decentering. </p>