Nikon V1 with dumb adapter and long zoom lens

I have a Sigma 170-500 zoom for birding with D50. At 500mm, never sharp enough. I switched to Panasonic FZ35 with 1.7 TC. With good light or on tripod, it is much better than D50+Sigma 170-500. I always suspect the blurry of the later is mostly due to mirror flap and shutter shock. Today, I attached the Sigma on V1 with fotodiox dumb adapter, using electronic shutter and remote trigger on tripod, the results are much better than D50+Sigma ever got. Especially using Sigma below 400mm, it is even sweeter and the reach is much longer of course.

The dumb adapter allows stop-down metering on Aperture Priority, the camera shows the exposure speed on screen, but need to switch to manual mode to take picture, because the camera sense no lens attached and does not allow to take picture other than manual mode.