Had hoped to compare the Nikonos 15mm to the Zeiss 24-70mm in Cocos but the Zeiss extension arrived the day after we left, oh well.
It took a little getting use to and I would say about 30% of the shots were just out of focus. But especially in low light, low contrast, poor viz situations there is something to be said for manual focus. The Nikonos lens requires good eyesight as the f-stop and distance numbers are small and a little hard to read. I had to turn the camera on it's "side" to read them. The focus peaking feature on the Sony A7 was actually helpful.
Sorry, can't figure out how to link from Flickr. So here is the link to the shots at my website. All these were taken with the Sony A7 and Nikonos 15mm will add RX100II shots later.
http://aquabluedreams.com/#/gallery/costa-rica-june-2014/dsc82301/