I recently purchased a Sony RX100 M2 with Nauticam housing. I have two INON 165 lenses for macro. I read various discussions on-line regarding how to focus for best macro: Zoom to max. and manually focus while using diopters. On land, before I had a chance to dive with the rig I did some experimenting and tried the DMF setting. It seemed that once manually focused the manual focus distance was maintained even after auto focusing for WA.
I finally got to try my RX100 M2 rig out in the water. Four days in the California Channel Islands with Wetpixel and Bradley Photographic. I set the camera to DMF the entire trip and manually focused one time only on dry land with my diopters on. When in the water I moved in to the point where it looked in focus. Then, I half pressed to get a solid green auto focus indicator. Not every image was sharp due to various issues: 1.) I didn't always maintain my position due to surge 2.) I sometimes pressed too hard and took shots when the auto focus light was blinking. When all the issues aligned correctly the images were very sharp. Unfortunately, I only had good macro subjects to work on my last two dives so I didn't get to do a lot of experimenting. I was able to switch to WA and back without messing with the manual focus at all....for the entire 10 dives! I need to experiment more and pay more attention to how close I actually am to the critter using this method. It seemed to me I was at the distance I would expect for the diopters I was using.
Here are a few of my results. I don't recall if I used one or two of the Inon 165s for the nudibranch photos but I do know this was on my 10th dive and I had not touched the manual focus since prior to dive 1. Yet, when I moved in close there was a point where I could see focus.
Has anyone else used this technique successfully?
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