Rokinon 8mm

[Richard]

I have a Rokinon 8 mm on a Sony A55 / Nodal Ninja 3 / RD16 rotator.
I have found the centering of the lens on the lower rail is 5.1 mm.,  
while my sigma 10-20 mm. and other lenses, are 5.4.5 mm..

Is this possible?  I thought all lenses on a camera are centered the  
same on the lower rail.

Richard

[Quebec360]

Hi Richard,

Each lens has it's own no-parralax point. Find it for every lens you use. Stick a piece of masking tape on the vertical rail of your NN3 and write your values on it. They will always be handy.

Luc


On 05 févr. 2012, at 14:49, rcgillespie wrote:

> I have a Rokinon 8 mm on a Sony A55 / Nodal Ninja 3 / RD16 rotator.
> I have found the centering of the lens on the lower rail is 5.1 mm.,
> while my sigma 10-20 mm. and other lenses, are 5.4.5 mm..
>
> Is this possible? I thought all lenses on a camera are centered the
> same on the lower rail.
>
> Richard
>
>

[Pat Swovelin-3]

On 2/5/2012 11:49 AM, rcgillespie wrote:

> I have a Rokinon 8 mm on a Sony A55 / Nodal Ninja 3 / RD16 rotator.
> I have found the centering of the lens on the lower rail is 5.1 mm.,
> while my sigma 10-20 mm. and other lenses, are 5.4.5 mm..
>
> Is this possible? I thought all lenses on a camera are centered the
> same on the lower rail.

It's a combo of the lens build and how it mounts on the body.  Is
everything tight on the head and where the body mounts to it?  Are you
positioning the vertical rail on the bottom rail by tilting -90° and
sliding the vertical rail until the center focus point on the ground
glass is centered over the NN logo on the rotator?

> Richard



Pat Swovelin
Cool Guy @ Large

[jrgen_schrader]

For best results I recommend to check the results on the final image.
Not by measuring and not through the viewfinder.
Probably there are some tolerances in lens manufacturing but In my setups I couldn't see any negative effect.  

--- In [hidden email], Pat Swovelin <panoramas@...> wrote:

>
> On 2/5/2012 11:49 AM, rcgillespie wrote:
>
> > I have a Rokinon 8 mm on a Sony A55 / Nodal Ninja 3 / RD16 rotator.
> > I have found the centering of the lens on the lower rail is 5.1 mm.,
> > while my sigma 10-20 mm. and other lenses, are 5.4.5 mm..
> >
> > Is this possible? I thought all lenses on a camera are centered the
> > same on the lower rail.
>
> It's a combo of the lens build and how it mounts on the body.  Is
> everything tight on the head and where the body mounts to it?  Are you
> positioning the vertical rail on the bottom rail by tilting -90° and
> sliding the vertical rail until the center focus point on the ground
> glass is centered over the NN logo on the rotator?
>
> > Richard
>
>
>
> Pat Swovelin
> Cool Guy @ Large
>

[Cuffsmaster]

I am going to bed  it is about 1:20 here

any final question before I end conversation tonight

On Feb 6, 2012, at 1:19 AM, jrgen_schrader wrote:

> For best results I recommend to check the results on the final image.
> Not by measuring and not through the viewfinder.
> Probably there are some tolerances in lens manufacturing but In my setups I couldn't see any negative effect.
>
> --- In [hidden email], Pat Swovelin <panoramas@...> wrote:
> >
> > On 2/5/2012 11:49 AM, rcgillespie wrote:
> >
> > > I have a Rokinon 8 mm on a Sony A55 / Nodal Ninja 3 / RD16 rotator.
> > > I have found the centering of the lens on the lower rail is 5.1 mm.,
> > > while my sigma 10-20 mm. and other lenses, are 5.4.5 mm..
> > >
> > > Is this possible? I thought all lenses on a camera are centered the
> > > same on the lower rail.
> >
> > It's a combo of the lens build and how it mounts on the body. Is
> > everything tight on the head and where the body mounts to it? Are you
> > positioning the vertical rail on the bottom rail by tilting -90° and
> > sliding the vertical rail until the center focus point on the ground
> > glass is centered over the NN logo on the rotator?
> >
> > > Richard
> >
> >
> >
> > Pat Swovelin
> > Cool Guy @ Large
> >
>
>