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View Full Version : New product candidate: Sigma 8mm on APS-C, to roll or not to roll?



nick fan
07-04-2008, 07:44 PM
to roll or not to roll, that is the question.
recent discussion has convinced me the advantage of having a roll of 30 deg (aligning the diagonal of sensor vertically)for single row spherical pano. I am thinking of making an adapter for Nodal Ninjas for this purpose. Will this capability bring advantage to a spherical pano head? After all, one can cover the zenith by tilting 5-10 deg upwards with 0 deg roll.
To keep the adapter compact, the NPP will not be at the pitch axis. So it is limited to single row only. I guess it is pointless to take zenith shot with 30 deg roll, right?
what do you think?
thanks a lot.


nick

Hub
07-31-2008, 04:02 PM
30? roll (diagonal) would facilitate 3 pictures pano (3 x around with Sigma 8mm)...
When the rotation axis is vertical, a small upward (5?) may be useful (in the case of some tree's branches above ; with roll =0?).
I would like to submit another situation, when the pole (or the monopod) is bending horizontally or at 20?. Look at the attached picture. It shows what I am doing. The feeling of the space is bigger if the nodal point is over the precipice. My equipement during the mountain trips include: Canon D350 with Sigma 8mm, NN3 and monopod Manfrotto. To take this panorama : http://annecypanoramique.free.fr/2008-04-20_Pas_du_Roc/20080413_13_Pas_du_Roc.html
I set NN3 10? down (in my direction). I took 5 pictures around the axis of bended monopod (I have been rotating the monopod with NN3 on it). It would change nothing if it was 3 pictures (in diagonal) and not 5. It is easy to rotate a monopod. But - keeping my monopod at 20?, I had the opposite side of the valley in my zenith. It was important to have the same sharpness of this part of my pano. I changed the settings of NN3 and took also a picture of zenith (roll 90? up for NN3, but 20? above the horizon).
Nobody propose a very light, manually operated pano-head for similar situations (out of the balloon, helicopter, precipice, NY skyscraper's window...). The rotation around the monopod axis can be made by the rotation of the monopode, but how to rotate the camera for the last zenith picture (holding the monopod in the same position all the time)?
Hub

nick fan
08-01-2008, 03:21 AM
Hi Hub,

Thanks a lot for explaining your special need. It will think about it when I work on monopod/ pole solution in the future.


nick

Yuv
09-15-2008, 08:09 AM
it is limited to single row only. I guess it is pointless to take zenith shot with 30 deg roll, right?
what do you think?


I studied the topic for my self-built NPP adapter. For an 8mm that's right, but already for a 10.5mm or for Tokina's 11-17mm there are situation when the ideal roll angle is not to align the diagonal vertically, but horizontally, and do multi-row. I found that at 10.5mm I can save an extra shot by doing two rows, one tilted up and one down, with a yaw displacement. I don't recall out of my head the exact numbers, but it was something like three shots up and three shots down with the diagonal oriented horizontally and the first row starting at 0? and the second at 60?. I came to the conclusion that a lens-ring is optimal for rolling.

Yuv