[null, null, {"document_url": "http://wiki.panotools.org/index.php?title=Remove_tripod_shadows&diff=next&oldid=14495", "unformatted_src": "/images/thumb/e/e4/Rocks-stitched.jpg/350px-Rocks-stitched.jpg", "src": "https://wiki.panotools.org/images/thumb/e/e4/Rocks-stitched.jpg/350px-Rocks-stitched.jpg", "formatted_filename": "px Rocks stitched", "alt_text": "Rocks-stitched.jpg", "rendered_width": 350, "rendered_height": 249}, null, null, {"document_url": "http://wiki.panotools.org/index.php?title=Remove_tripod_shadows&diff=next&oldid=14495", "unformatted_src": "/images/thumb/8/8c/Patch_0.jpg/340px-Patch_0.jpg", "src": "https://wiki.panotools.org/images/thumb/8/8c/Patch_0.jpg/340px-Patch_0.jpg", "formatted_filename": "px Patch", "alt_text": "Patch 0.jpg", "rendered_width": 340, "rendered_height": 340}, null]
Difference between revisions of "Remove tripod shadows"


Revision as of 17:29, 1 December 2012

Many panographers like to present a pure spherical image, with no sign of the photographer or his/her apparatus. It is widely known how to use an additional "nadir shot" to replace the image of a tripod, but somehow it seems more difficult to eliminate the shadows of the tripod, pole, and photographer from a pano taken at a strongly lighted spot. However, this can be done by applying the same principle: combine several shots in which the shadows are in different places.

If all images are taken from a fixed lens position, the shadow of the camera itself must be at the same place in all of them. But we can move the shadow of the support, simply by moving the support. This is easiest if the camera is mounted on a telescoping monopod or pole, but can be done with a conventional tripod as well. And when the camera shadow is sufficiently far away, it is possible to get a completely clean 'patch shot' by shifting the camera slightly to one side of the panocenter.

As in all other aspects of photography, the key to success is visualizing problems before shooting, and planning ways around them. First, you must be aware of the direction of the light that is making the shadows. You will need to move things at right angles to that direction in order to to shift the shadows. Second, choose a spot where the shadow of the camera itself is either far away or in a dark place, perhaps inside some natural shadow that will be part of the picture. Make sure the chosen spot gives you enough room to maneuver yourself and your equipment. If using a tripod, try to place it so the shadows of two legs coincide.

When taking the fixed shots from panocenter, take care that your own shadow is not in any of them; or when that is not possible -- for example when shooting from a hand-supported pole or using a cable release -- take each shot in which your shadow appears twice, once standing to the left of the camera and once standing to the right.

If using a tripod, extend its center column as much as possible for the fixed shooting. Then fold the legs and use it like a pole. You will need more slant than with a pole, to let the camera see past the tripod's shoulders. It may be feasible to extend the legs, but I usually just hold it up in the air.

Sometimes the same shot can serve as both nadir patch and shadow patch, but it is best to take them separately, optimizing each for its particular function. In fact it is a good plan to take several shadow patches, for two reasons. It is much easier to align a small patch well than a big one. But more important, in a single shot you can easily have part of your shadow where part of the tripod shadow was -- it isn't there anymore, so it's hard to tell. If you take two, standing on opposite sides of the shadow area, with the pole slanted in opposite directions, it is much more likely you will cover everything.

In difficult cases you can try advanced patching tricks such as using the same patch twice with different control points and mask. But if you plan and execute your shooting carefully that should not be necessary.

Example 1: monopod supported by hand Before stitching I masked out the shadows and the top of the monopod in all images, and masked all but the relevant part of the patch image. The last picture shows that part of the stitched panorama. You can see the interactive version here.

Example 2: pole supported by tripod

15mm fisheye lens on a 1.6 crop DSLR mounted on a pole that rotates on its own ball-jointed foot. For the fixed shots (6 around down 55 degrees, 8 around level; 6 around up 55 degrees) the pole was supported by a medium-weight tripod via a plastic spring clip that lets me separate the pole from the tripod with a firm pull. Before stitching, I painted masks over all shadows and images of myself and the support. After stitching all the shadows were gone, and I just had to clone out two tiny unpatched areas at the nadir and on the bottom fence rail.

The full size interactive panorama is here.

-- 30 November 2012 Thomas K Sharpless

Retrieved from "http://wiki.panotools.org/index.php?title=Remove_tripod_shadows&oldid=14496"


