[Leica] OT: Technical Question- Panning vs WA Lens

[henningw at archiphoto.com (Henning Wulff)]

...and if you really want lots of detail, with 
not a big capital outlay or fuss, see:

http://www.gigapan.org




At 7:54 PM -0700 4/18/11, Bob Adler wrote:
>Thanks to all who have given thought to this question. Sorry to have been
>missing from the thread; lots of other work this afternoon.
>
>As the Esteemed Dr. Ted would say, and as Henning implies, stop talking and 
>go
>shoot! ;-)
>
>So that I will. I will go out this weekend, after I get the rail to adjust 
>for
>the nodal point, and take some images panned with the 80 and with the 40. 
>Then
>we'll see the differences (I will post).
>
>Also, in answer to Herb's good question, 
>Photoshop and other programs do seem to
>accommodate for the lack of perfect flatness.
>
>The Arcatech GP bullheads both (the "s" and non-"s") have a 25lb capacity. I
>have no hesitation using it with the Hassy.
>
>So thanks again everyone. I'll share the results.
>Best,
>Bob
>
>PS - My guess is that I'll get up there having tried to plan this whole
>weight/flexibility thing out and, after the 
>first day of hiking with the Hassy,
>I'll end up taking only the Lumix with me the 
>rest of the time. I can hear Tina
>chortling now...
>
>
>  Bob Adler
>Palo Alto, CA
>http://www.rgaphoto.com
>
>
>
>
>________________________________
>From: Henning Wulff <henningw at archiphoto.com>
>To: Leica Users Group <lug at leica-users.org>
>Sent: Mon, April 18, 2011 6:17:34 PM
>Subject: Re: [Leica] OT: Technical Question- Panning vs WA Lens
>
>This topic is a lot more complex, the answers are a lot more varied and in 
>the
>end, almost everything is possible.
>
>First, you have to determine what type of 'panorama' you want.
>
>You can produce a wide angle photo of basically three types:
>
>Type 1: rectilinear, like a good wideangle lens 
>produces. What your 40 Distagon
>would produce, or an Xpan produces.
>
>Type 2: cylindrical, like what a Cirkut camera produces or what a Noblex,
>Horizon, Widelux (manufacturer: Panon) or Roundshot produces.
>
>Type 3: Fisheye.
>
>Each has advantages and limitations.
>
>Type 1 cannot have a diagonal angle of view of 
>180?; in fact, as a one shot more
>than 125? is difficult and you need lenses like the Hyergon to achieve them.
>
>Type 2 can have any horizontal angle of view you want, including over 360? 
>but
>not more than about 110 or 120 vertical.
>
>Type 3 can show over 180? in any direction, and 360? around the 
>circumference.
>
>But:
>
>Type 1 starts showing distorted 3-dimensional objects in the corners when 
>you
>get over about 70? diagonal, and that gets quite severe when you're over 
>100?
>diagonal.
>
>Type 2 avoids the above, except for 3 dimensional objects close to the 
>zenith
>and nadir when the vertical angle is over 70?, and horizontal lines off the
>center get bowed.
>
>Type 3 has varying magnification to get it's job 
>done, so rectilinear distortion
>is quite severe, and the objects at the images's edges is often too tiny to 
>be
>of much use.
>
>You can use Photoshop, or other more sophisticated stitching programs such 
>as
>RealViz Stitcher to produce any of the above. You can also stitch multiple
>frames in a pattern like 3 across and 3 down to get hi-res images from 
>lo-res
>cameras.
>
>Another topic:
>
>Using a proper pan setup becomes more important, the closer you are to the
>closest part of you scene, and finding the nodal point becomes more 
>important
>when there is a large difference in close and far image points, and the 
>closer
>you are to the close point.
>
>Finding the correct nodal point is quite simple, and should not be taken 
>from
>diagrams or calculations as it's easier and more accurate to do visually.
>
>With an SLR or live view camera, it's easier still.
>
>Set your camera up so that the lens axis is over 
>the rotational axis of your pan
>head. Aim your camera at a thin stick that is about 2 feet in front of your
>camera, and that has a scene behind it. Rotate 
>your camera so that the stick is
>at the left side of your field of view. Note where the stick is in relation 
>to
>the background scenery. Now rotate the camera so that the stick is near the
>right edge of your field of view. If the vertical rotation axis is through 
>the
>nodal point of the lens, the stick will not have shifted with respect to the
>background. If it has shifted, move the lens backward or forward over the
>rotation axis until the image does not shift with respect to the background.
>That's it. Note the numbers, or make a scratch, 
>or whatever as that position for
>the lens is the correct one. Calibrate the setup 
>for each lens you will want to
>use. If you insist on using a zoom lens, 
>calibrate at each focal length you want
>to use, as the nodal point will shift, often drastically.
>
>
>As you might guess, I'm very interested in this and have, besides my 8 
>lenses
>for Leica that are 21mm and wider, the Xpan with 
>30mm, Horizon 202, Noblex 150U,
>Roundshot 220/28, a lot of shift lenses and fishey lenses, Hasselblad SWC, a
>couple of CamboWide cameras and quite a number 
>of large format lenses that cover
>between 100 and 125?.
>
>In any case, Bob, you can use whatever lens you want to stitch. If you want 
>a
>given angle of view, using longer lenses will mean more exposures to capture
>every part of the solid angle, will mean more chances of mistakes (like
>forgetting a certain part of the mosaic), more chance that something in the
>scene will change while you do your series and will give you a larger file 
>in
>the end with more detail. For your purposes, I'd suggest you go for 3-5 shot
>panoramics if you are going to stitch them all 
>horizontally, and go for a 'flat'
>stitching or 'cylindrical', and go for a 2x2 or max 3x3 if you are going to
>stitch them in multiple rows and colums, and do 
>all of this with the widest lens
>you are taking. And practice beforehand. :-)
>
>
>
>
>
>At 12:55 PM -0700 4/18/11, Red735i wrote:
>>  The problem is that you will be pointing the lens in different direction
>>  with Panning.... which means that the image perspective is different for
>>  each frame....
>>  Perspective is always dependent on distance to the subject, but too, in 
>> that
>>  definition is that the subject is always in the same relative angle to 
>> the
>>  camera.  When you pan, this breaks the rules...perspective changes.
>>
>>  Do you remember the old Circuit cameras that made images from a moving 
>> lens?
>>  ( More modern examples are the Panon and Widelux Cameras...).....
>>  The particular perspective could not be copied compared to stitching....
>>  because at each and every image location ( think in terms of a swinging 
>> lens
>>  that moves in precise increments) is perpendicular to the lens....  
>> Whereas
>>  in WA lenses, the extreme right and left of the image is actually quite 
>> an
>>  angle from the optical axis of the lens....
>>
>>  The results are different....  ( not better, not worse, just 
>> different)....
>>
>>  The most interesting thing about this topic is that the swinging camera
>>  approach is most close to what your brain actually sees through your 
>> eyes...
>>  you usually pan your head when you look at a scene...  rarely do you use
>>  peripheral vision, which is more like a WA lens .....
>>
>>  OTOH, 99.99999999999% of the population would never know the 
>> difference....
>>  and of those that do, 99.9999999% would not care.
>>
>>  But don't let an architect catch you......
>>
>>
>>  Frank Filippone
>>  Red735i at earthlink.net
>>
>>
>>
>>
>>  I am trying to understand if I can take a wide angle photo using
>>  panning/stitching with a normal lens that would look like it was taken 
>> with
>>  a WA lens. My specific question is if I can get the same coverage and
>>  perspective using an 80mm Hassy lens and panning/stitching 3 or 4
>>  overlapping shot as I could with the 40mm Hassy.
>>
>>  If so how would this best be accomplished? Standing back further with 
>> the 80
>>  than with the 40 or just at the same spot with the panning. Would the
>>  image's perspective be the same?
>>
>>
>>
>>
>>  _______________________________________________
>>  Leica Users Group.
>>  See http://leica-users.org/mailman/listinfo/lug for more information
>
>--
>       Henning J. Wulff
>Wulff Photography & Design
>mailto:henningw at archiphoto.com
>   http://www.archiphoto.com
>
>_______________________________________________
>Leica Users Group.
>See http://leica-users.org/mailman/listinfo/lug for more information
>
>_______________________________________________
>Leica Users Group.
>See http://leica-users.org/mailman/listinfo/lug for more information

-- 

       Henning J. Wulff
  Wulff Photography & Design
mailto:henningw at archiphoto.com
   http://www.archiphoto.com