Ion

09-21-2008, 06:16 AM

Hi everyone (and John; I'll be needing you again),

* I have been working on the calibration of my D300 + Nikkor 10.5 on my NN5L.

Things work out oke but I'm still puzzled with the no-parallax-point calibration for the zenith shot.

I use a -15 angle for smaller nadir footprint. I am wondering what the 'optimal' zenith angle would be. I have been shooting +60 / +90 and +75 degrees.

Actuall the +60 gave me best (at least easiest) results when stitching outdoor scenes with clouds or air cause you have a reference 'on the ground' for control points.

I have been thinking (correct me if I'm wrong) if it would be more correct to shoot at a +75 degrees angle. -15 + 90 = +75 degrees (similar angle as if you would use 0 degrees and a 90 degrees zenith shot).

Or would 60 degrees increments work better (same angle used for the vertical shots), for example +45 degrees (but here the covered area will be too small I think) or +105 (so -15 actually) or is this mathematical mumbojumbo? :-)

For vertical parallax should the same method be used to find the NNP and rotate the camera around the horizontal axis with +-45degrees (or +-30 degrees when using a 60 degrees angle for the zenith shot)

* Secondly... Hans Nyberg can confuse you sometimes too you know haha :-)

http://www.panoramas.dk/panorama/fisheye-NPP/parallax.html

I suppose this is applicable too the 10.5fish as well? So it's not only the angle used for the photo's (the amount of shots to cover the 360degrees) but also the place on the photo itself where you want to avoid parallax, that are important to find the "NNP". What influence does Hans's theory have on your 'classic' (with the tape on the window) method for finding the NNP, John?

The more I learn and think I understand about pano's, the more I discover that has to be learned and done.

Best regards, Wim.

* I have been working on the calibration of my D300 + Nikkor 10.5 on my NN5L.

Things work out oke but I'm still puzzled with the no-parallax-point calibration for the zenith shot.

I use a -15 angle for smaller nadir footprint. I am wondering what the 'optimal' zenith angle would be. I have been shooting +60 / +90 and +75 degrees.

Actuall the +60 gave me best (at least easiest) results when stitching outdoor scenes with clouds or air cause you have a reference 'on the ground' for control points.

I have been thinking (correct me if I'm wrong) if it would be more correct to shoot at a +75 degrees angle. -15 + 90 = +75 degrees (similar angle as if you would use 0 degrees and a 90 degrees zenith shot).

Or would 60 degrees increments work better (same angle used for the vertical shots), for example +45 degrees (but here the covered area will be too small I think) or +105 (so -15 actually) or is this mathematical mumbojumbo? :-)

For vertical parallax should the same method be used to find the NNP and rotate the camera around the horizontal axis with +-45degrees (or +-30 degrees when using a 60 degrees angle for the zenith shot)

* Secondly... Hans Nyberg can confuse you sometimes too you know haha :-)

http://www.panoramas.dk/panorama/fisheye-NPP/parallax.html

I suppose this is applicable too the 10.5fish as well? So it's not only the angle used for the photo's (the amount of shots to cover the 360degrees) but also the place on the photo itself where you want to avoid parallax, that are important to find the "NNP". What influence does Hans's theory have on your 'classic' (with the tape on the window) method for finding the NNP, John?

The more I learn and think I understand about pano's, the more I discover that has to be learned and done.

Best regards, Wim.