Can annyone give me advice on what port i schould buy for my 12-24. The only test i can find is the one from 3 years back . In that test the advice is to use the nexus 170 mm port with 40mm extension but in the meanwhile nexus has a special port for the 12-24 and a new dome of 160mm in glass. But i cannot find any revieuws on these. I am affraid to buy something wrong. I do not want the lens to vignette or have the corners soft.Has anybody experience with this. PS my housing has style 4 thread

Hi

I am not a NIKON user But I use the FP160 Dome with a 15mm fischeye. My test if the FP160 Dome and the 67mm extension with the 16-35 USMII did not yet satisfy me at the corners shot is taken with the canon 16-35usmII at 16mm / f16 in the anthis FP160 Dome with a 67mm extension on a EOS5D. Unfortunately I did nit find a bigger dome so far. I would believe that the new athena 200 vario dome would be the best try for me. unfortunately this is not the cheap solution but i really would like to see the results. 

In general I would expect if NEXUS (anthis.com.jp) is recommending a special port then it can not be wrong to use it. on the other side this is very specialized and I also would like one dome for all.

I was reading this detailed test on the FP170 and the NIKON 12-24:
http://www.gotosnapshot.com/digital-slr/digital-photography-17.shtml

marinecamera recommends the NEXUS Ext40mm FP170 Dome:
http://www.marinecamera.com/nexus_ports.html
http://www.marinecamera.com/gettingwider.html

another user of that combination:
http://www.goldenstateimages.com/Nexus_Nikon_D200_Housing_Review.htm

most likely this does not bring you much further, I guess

Thanks for the reply. But like you said this does not solve my problem . All the articles you have mentioned ,i have already read myself.I am searching for the right solution for over a year now.And have been in front of the PC for ages . What i need is that sombody can confirm that the nexus port for the 12-24 is ok ,by means of scharpness ,and that untill the corners.