For your lens you need 15 shots around @zoom 40 for example. There is no detend ring available to do 15 shots around at 20º. This is point one. I just tested zoom @ 17 and 40 for shots around.
On standard rotator you have to open up the rotator to change the number of shots around to place a new ring or turn it around. With RD8/RD16 you just place the detend knob to another hole to get a different number of shots around on the fly.
RD8/16 Rotators can be used on M1 line, standard rotator not. I should think of getting a RD16 Rotator to be ready for the future. May be you will need different settings using other lenses once you might be infected with the panovirus. Take the amount of money in calculation of buying a RD 8 or RD16 rotator later on inclusive transport. But it is your personal choice depending on your personal situation and engagement on panos right now.
I have tested from standard rotators on NN3 to RD16 on NN5, NN4 and M1. So I know the differences in comfort and use.
For your lens you need 15 shots around @zoom 40 for example. There is no detend ring available to do 15 shots around at 20º.
The two sided detent ring on the NN4 starter edition would allow 15 shots around (27% overlap) or 18 shots around (39% overlap). Alternate detent positions would be used. This is quite practical, but I think mistakes in selecting the correct positions might possibly be made in busy circumstances.
http://www.youtube.com/watch?v=rbET5K75zJw Changing the detend ring is the same for NN3 MKII as for NN4 standard rotators in principle. Imaging, that besides what is mentioned in the video you have to take off the camera from the panohead as well.
There is another video about RD8 rotator, where you can see the changing of the detend plunger knob and compare it.
@zoom 40 you have to take 3 extra shots because you can only get a 20º detend ring with 18 shots around instead of 15 for standard rotator. This makes 3 extra shots per row, with bracketing 3 this makes 3x2 = 6 extra shots per row.
The difference from NN4 standard rotator to NN4 with RD8 is $40, to RD16 is $90 without extra detend rings. To change from standard rotator to RD4/RD16 later on will cost you $149.95/$199.95 plus extra shipping costs.
The upgrade to RD8 has an extra price of around $20 in total. You should keep all this in your mind taking your decision.
Last edited by hindenhaag; 08-17-2011 at 09:39 AM.