Still getting sorted out with my new NN3 and my setup : Canon 40D with Canon 17-40 lens.
Basic Question here in aligning my Lower Rail for this set up and shooting at 17mm...
The question relates to pointing the camera down and looking through the viewfinder. In the NN3 manual it states that when pointing the camera down, you should see the NN3 knob's bullseye in the center of the frame.
I am intepreting this correctly?
On NN suggested settings (http://nodalninja.com/nodal_ninja_3_..._settings.html) it lists a suggested lower rail setting of 58mm when the lens is set to 17mm.
However, If I do this and point the camera down at the nadir, I do not see the NN3 bullseye in the center of the frame.
It seems I have to set it at ard 54 or 55mm to get the center of the frame to align with the NN3 knob's bullseye.
Note - I AM using the camera plate provided with the NN3 kit.
Please help, as I want to make sure to eliminate parralax in my panos...
Welcome to the forum.
The settings could be off +/- a couple mm's either way. This generally is not a problem for most but still the closer the better. Also when centering through the viewfinder of the lens "some" viewfinders do not have a true bull's eye that equates to the center of the lens. It's easy to determine the lower rail settings by looking through the viewfinder with camera pointing straight down and rotating it. If you see a slight wobble it's off center. Tweak until you have no wobble and set with the rail stop. The lower rail setting will never change regardless of lens and focal length (as long you you don't change camera bodies).
On the upper rail settings use the setting suggested on the settings page. Any errors you get might be a software tweak. The manual also suggests how to find the upper rail setting manually which we always encourage folks to learn. Knowing how to find the no parallax point of virtually any lens at any focal length is easy to do once learned.
Keep us posted on you go.