If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Panoramas and nodal points
Hi, I'm building my own pano head for taking panoramas - and it might not be an engineering masterpiece. Would I be right in saying that the accuracy and effectiveness of the pano head will be in a direct ratio to my accuracy in building it? I.e. Would I be right in saying that if my pano head allows rotation *nearly* around the nodal point, the image will be *nearly* as good as if I were 100% accurate? Or is it all or nothing ? Bob T. |
#2
|
|||
|
|||
Panoramas and nodal points
Bob Thomas wrote:
Hi, I'm building my own pano head for taking panoramas - and it might not be an engineering masterpiece. Would I be right in saying that the accuracy and effectiveness of the pano head will be in a direct ratio to my accuracy in building it? I.e. Would I be right in saying that if my pano head allows rotation *nearly* around the nodal point, the image will be *nearly* as good as if I were 100% accurate? Or is it all or nothing ? Bob T. That depends on the stitching software that you use. Most of them can handle minor alignment problems in all 3 axis. Some of them can deal with rather significant problems. A few can't handle much at all. I would suggest you try it and see. I have a Manfrotto pano head that does a great job. I use Hugin and Photoshop CS for stitching. I will also shoot hand held panos, when the tripod isn't there or practical. Hugin usually handles it without much problem. PS CS isn't too bad either - well, for less than 360 degrees. Clyde |
#3
|
|||
|
|||
Panoramas and nodal points
Try www.PanoramaFactory.com. Infinitely better than PS.
Graham "Clyde" wrote in message news:TBdEc.129378$HG.73390@attbi_s53... Bob Thomas wrote: Hi, I'm building my own pano head for taking panoramas - and it might not be an engineering masterpiece. Would I be right in saying that the accuracy and effectiveness of the pano head will be in a direct ratio to my accuracy in building it? I.e. Would I be right in saying that if my pano head allows rotation *nearly* around the nodal point, the image will be *nearly* as good as if I were 100% accurate? Or is it all or nothing ? Bob T. That depends on the stitching software that you use. Most of them can handle minor alignment problems in all 3 axis. Some of them can deal with rather significant problems. A few can't handle much at all. I would suggest you try it and see. I have a Manfrotto pano head that does a great job. I use Hugin and Photoshop CS for stitching. I will also shoot hand held panos, when the tripod isn't there or practical. Hugin usually handles it without much problem. PS CS isn't too bad either - well, for less than 360 degrees. Clyde |
#5
|
|||
|
|||
Panoramas and nodal points
Bob Thomas wrote:
Hi, I'm building my own pano head for taking panoramas - and it might not be an engineering masterpiece. Would I be right in saying that the accuracy and effectiveness of the pano head will be in a direct ratio to my accuracy in building it? I.e. Would I be right in saying that if my pano head allows rotation *nearly* around the nodal point, the image will be *nearly* as good as if I were 100% accurate? Or is it all or nothing ? Bob T. I have lost track of it, but somewhere recently I read a cogent argument that for DigiCams the normal-to-nodal-point distance has shrunk to insignificance, and that even in ordinary camera scale, the requirement that pivot and nodal points coincide was always overrated, anyway. So, who was it said that? Speak up, please. Frank ess |
#6
|
|||
|
|||
Panoramas and nodal points
Yes the closer the better - but even with perfect there will still be some
work to do. -- http://www.chapelhillnoir.com home of The Camera-ist's Manifesto The Improved Links Pages are at http://www.chapelhillnoir.com/links/mlinks00.html A sample chapter from my novel "Haight-Ashbury" is at http://www.chapelhillnoir.com/writ/hait/hatitl.html "Bob Thomas" wrote in message ... Hi, I'm building my own pano head for taking panoramas - and it might not be an engineering masterpiece. Would I be right in saying that the accuracy and effectiveness of the pano head will be in a direct ratio to my accuracy in building it? I.e. Would I be right in saying that if my pano head allows rotation *nearly* around the nodal point, the image will be *nearly* as good as if I were 100% accurate? Or is it all or nothing ? Bob T. |
#7
|
|||
|
|||
Panoramas and nodal points
Clyde wrote in news:TBdEc.129378$HG.73390
@attbi_s53: That depends on the stitching software that you use. Most of them can handle minor alignment problems in all 3 axis. Some of them can deal with rather significant problems. A few can't handle much at all. Absolutely not! No stitching software can handle pictures better than any other if there are probblems with not rotating around the nodal point. Tilting and rotation, yes, then you want to use Panorama Tools - it is the best one for dealing with those kinds of problems. But - none can handle nodal points mismatch. /Roland |
#8
|
|||
|
|||
Panoramas and nodal points
"Tony Spadaro" wrote in
. com: Yes the closer the better - but even with perfect there will still be some work to do. I would rather phrase it like this * For panoramas with only far away objects - don't bother with any nodal points at all - it is not important. You can, if you want - try to rotate around the camera at least. * For panoramas where the nodal point starts to become important, any crude device that approximately rotates around the nodal point is of extremely high value. * I would be surprised if you would find any situation where the crude device is not enough. Objects must very near to the camera indeed. /Roland |
#9
|
|||
|
|||
Panoramas and nodal points
"Tony Spadaro" wrote in message
. com... Yes the closer the better - but even with perfect there will still be some work to do. If you use software like PanoTools it is unlikely to be an issue. That will do all the "work" for you. Cheers, David |
#10
|
|||
|
|||
Panoramas and nodal points
"David J Taylor"
wrote in : "Tony Spadaro" wrote in message . com... Yes the closer the better - but even with perfect there will still be some work to do. If you use software like PanoTools it is unlikely to be an issue. That will do all the "work" for you. Yepp - why would it be so extremely important to find the exact nodal point? Let us say that you miss the nodal point with 3 mm (thats a lot of you make a crude bracket). Let us further say that you rotate the camera 20 degrees between photos. Then the (virtual) nodal point will move 3 mm*2*tan(20/2) = 1 mm sideways. This means that nearby things will be 1 mm wrong with regard to infinity. Using a 50 mm lens (35 mm equiv) and a spacing of 10 um (reasonable for a full frame 35 mm digital camera), then 1 mm will correspond to one pixel wrong at 5 meters. So - if you have objects nearer than 5 meter you must find the nodal point with an accurace of 3 mm to assure better than one pixel accuracy. /Roland |
|
Thread Tools | |
Display Modes | |
|
|