View Full Version : Accuracy of Rail Measurements and 70-200 VRII Nikon
01-01-2010, 08:35 AM
Ok all, Third post since getting into this....Here is my next question and I have looked and searched the forums.
I am trying to find the Nodal Point on a D3s and a 70-200 VR II lens with a NN5 and RD16. Using John's string method to find the bottom rail measurement, I have come up with a 88 to 87. Other have emailed me that a D3 should be 86. I am toooooo new to argue or understand to that is my post question. Is there a difference between 87 and 86?
Finding the upper rail measurement, Johns method of moving left and right +/- 30 degrees makes the lens itself block the visible nodal point viewable in the lens at 0 deg. Should I do it less than 30 degrees left and right? A little help with the longer lenses is I guess what I am asking for too.
01-01-2010, 10:00 AM
you seem to be working hard on this, or is this because we have a free day? I have been out a little deep freezing today at 3 degrees celsius taking panoramas to compare the same spot with D3 50mm/f1.4, 16mm/f2.8, 14-24mm/f2.8 at zoom 14, 16 and 24. I ended up with a dropping nose, cold feet and hands. But it was one of the bit sunny days, - forum members like to see sunny panos...- no wind, no clouds, few people walking around. So i could go on shooting without having to wait for people to leave the sight.
Now, you wound find a lot of information about your combination.
First thing: lower rail setting for D3, D3s, D3x is 86, i use this setting for my D3 and it is correct. The body of all these cameras is the same, which means same distance lense flange to sensor plane and the same position of the tripod mount. Because of this the lower rail setting is the same.
Just use this lower rail setting. You have to be precise with the rail settings to pick up the NNP besides you use long lenses. Then it is not so critical to be off the NNP. But better even then use the correct settings.
Concerning the 70-200 VRII, i am not sure about the settings. It is said to be a new construction combined to the older 70-200 VR, so it might be that you have to find new NNP's for the lens. I will try to add the setting for the lens VR to this comment, but at the moment there seems to be an overflow of bills server with the additional options. I prefered to spend my money to a R1 and a sigma 8mm/f3.5 than to change my VR into a VRII. So i have to raise my ISO and use DxO for noise reduction running into trouble in low light conditions.
The 70-200 is a tricky lens cause of its NNP's. From zoom 105, you have to turn the upper rail to the front and mount the lens with its own tripod mount to the rail. I use the hole closer to the lens cap, and place the mounting plate with its long side
of the plate ( 2 : 1 in length reference to the big yellow mounting screw) to the camera body. The NNP for zoom 200 is behind!! your sensor plane.
OK, i try to send it with additionals,
01-01-2010, 10:35 AM
You are correct about the free day. I am really interested in Panos and getting the right. I will use 86!!!!
I am using the Cp-2 since thins is a new NN5 purchase. I am also using a Really Right Stuff Arca lens foot for the lens and need to compare it to the Nikon Lens Foot about holes and location. I am still working on this....thanks for the reply! I will reply to this post after doing a quick Honey Doo thing.
01-01-2010, 03:06 PM
there is no difference between CP1 and CP2 mounting plates about the rail settings. Just recieved my new CP2's before christmas and checked it. Lower rail settings stay the same. Same thickness as CP1. So Nick knows what he is doing fro us.
Really Right Stuff is really a good stuff. Just add the CP2, but adjust it the way that the short side of the CP2 shoes to the lens cap, you will have to face something to 135 mm.
Enjoy your quick Honey Doo thing...
01-01-2010, 03:18 PM
In my playing and measuring, I found out that the Really Right Stuff foot that I have has one tripod screw hole which is 7mm different that the Nikon foot. In changing out the RRS foot to the Nikon foot and setting it up at 135 and measuring to the back plane of the camera from a point on the upper rail I received a measurement of 5.5 inches. In switching feet back to the RRS and measuring to get the same distance from the point on the upper rail and the back plane of the camera I needed to set the rail measurement to 128 to get the same 5.5 inches. I think that was my problem is the holes on the feet are in a different position.
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