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PostPosted: Thu Sep 18, 2008 11:14 pm 
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I just found this motorised pano head http://www.thegadgetworks.com/index.html
Unfortunately for this model there is no way to adjust the vertical nodal point.


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PostPosted: Fri Sep 19, 2008 12:56 am 
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pix2pixels wrote:
I just found this motorised pano head http://www.thegadgetworks.com/index.html
Unfortunately for this model there is no way to adjust the vertical nodal point.

We all agree with you… NPP means (No parallax Point)
Just a small adjustment in the initial theory, there is almost no NPP to take care of when a tele lens is involved, just because NPP is a ratio with near and far objects…
If you are taking a picture at more than 2 to 3 meters away… This NPP rule becomes outdated… why !
NPP is only very sensitive to close and far objects. This can make a very funny perspective result.

Just consider that you are taking a picture from your seat, then turn your head and observe that the window's foreground and window's background are messing up … don't you !!!
To resolve that geometry perspective point is only a perspective projection's problem … Get closer to the Windows's view and you'll see that there are no more movements… This is what we call no NPP, No parallax movement…

Most of the time fisheye and ultra wide angle lens are very much concerned with very precise NPP. Tele lens are a lot less concerned by the phenomenon.

Keep asking and keep wondering to get a picture of the whole problem… It can help the whole community :)

Any way, Thanks for thinking !!!


Last edited by beeloba on Fri Sep 19, 2008 1:01 am, edited 1 time in total.

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PostPosted: Fri Sep 19, 2008 11:01 am 
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beeloba wrote:
If you are taking a picture at more than 2 to 3 meters away… This NPP rule becomes outdated…

Yes ... and no !

Whether it's outdated depends of the size and DOF of the resulting image: on subject parts at more than 20 or 30 meters you will see parallax errors on gigapixels panos taken using a long or very long lens using a small aperture. You will not see them on "ordinary size panos" nor when DOF is not high enough.

Suppose the NPP moves by 1 cm between two shots and suppose there is an object at 20 meters against an "infinity background": if the resulting image size is large enough (so that 1 cm details at 20 meters are visible) and the DOF is large enough (so that so that 1 cm details at 20 meters are crisp) then NPP rule is not outdated.

Those small parallax errors are something Smartblend handles very well but Smartblend is not always the best blender for gigapixel panos...

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Last edited by GURL on Fri Sep 19, 2008 12:39 pm, edited 1 time in total.

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PostPosted: Fri Sep 19, 2008 11:54 am 
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You are right Gurl :)


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