Meet My Friend Bo

I've been working with a new panorama tool this past month or so, and I'm liking it a lot.

It's the Bo Bracket, a simple, light, accurate panorama bracket made by Bo Lorentzen, a photographer and computer graphics artist. The bracket is made of model aircraft birch plywood, cut with a precision laser and laminated.

The bracket is designed for specific lenses.  I ordered mine to fit my Sigma 8mm f/4 fisheye.  It's also available for the Sigma 8mm f/3.5, the AF Fisheye-Nikkor 10.5mm f/2.8, and several point-and-shoot fisheyes. 

Its construction is simple - the base with 3/8" tripod mount socket, the lens bracket, and a long screw with wingnut to hold it all together. It clamps around the lens, allowing it to be rotated around its no-parallax point (NPP), or "nodal point". 

Bo recommends using a Manfrotto 259B tripod extension column as a rotator, since the base of his bracket is too small to allow attachment to a regular size tripod head.

I'm using mine atop a short metal post that originally was part of a Forscher Polaroid back for a 35mm film SLR. (Moral of this story - never throw any piece of photo gear away, no matter how obsolete).

The post and Bo Bracket go atop a monopod, and I rotate that, being careful to keep it as vertical as possible. This is very similar to how I used the Nodal Ninja 3 on the campaign trail earlier in 2008. It's very helpful to use a hot-shoe two-axis bubble level

or a surveyor's rod level to keep the monopod vertical. 

I use the monopod from both ground level and holding the monopod up as high as I can. In the picture at left, I'm using my credential holder to hold up the monopod. A flag holder like you might see in a parade would work very well for this. And of course, you'll need a wired remote release.

There are a couple of things to be aware of. In my early testing, I was using the bracket with a Nikon D200. The overhang of the D200's prism cover contacts the bracket, but I was able to turn the lens 90 degrees and mount the camera. Depending on the camera model, this may prevent getting the lens fully into the bracket, thus missing the NPP.

Also, the instructions included with the bracket caution that it's very sensitive to moisture. It's recommended to coat it with epoxy if it's going to be used in wet environments.

The one thing the bracket can't do is to swing up and down to shoot zenith and nadir precisely from the NPP. In the tests I shot (not shooting up or down, but just around), the zenith hole was minimal and could easily be patched by editing the top cube face. The footprint of the bracket is quite small, making a nadir patch easier. The nadir can be shot handheld away from the NPP if necessary. PTGui's viewpoint correction feature makes stitching these off-NPP images much easier.

I put the rig to the test this past weekend at the new zMax Dragway @ Concord. Check out the three panoramas on this page of Thatsracin.com, our motorsports website. These panos were all shot with the Nikon D700 full-frame sensor camera and my trusty Sigma 8mm f/4 fisheye. I've wanted the three-frame advantage of a full circular image, and I wasn't disappointed. I'll post my impressions of shooting and stitching circular images in the next few days.

Way Useful Lens Database

Thanks to Nhat V Meyer of the San Jose Mercury News for posting (via the NewspaperVideo Yahoo group) a link to VRWave.com. It looks like the site is under construction, but it's already worthy due to its excellent list of lenses (Canon, Nikon, etc.) and their specifications for panoramic use.

Not only do we use fisheyes for panoramas, we can also use conventional lenses (both prime and zoom). And, we don't have to shoot full 360x180 panoramas - partial cylindrical panoramas can work quite well for story telling especially if you need a really wide view. If you remember the Widelux or Horizon panoramic film cameras, these panoramas will remind you of that"bananarama" effect. Here's an example I shot earlier this year where I needed to have both the building we were reporting on and the skyline. Another advantage of cylindrical panos is they're easier to publish in print - you don't have the extreme distortion at the top and bottom of the images as in equirectangular projections.

The database includes Field of View parameters for these lenses, and (this is the best part) it tells you how to set up a multi-row panorama. The key info is: pitch in degrees for each row, number of rows, and number of images per row. This is key information if you're going to stitch a multi-row, high-resolution panorama for posting to gigapan.org (see an earlier post for details). PTGui handles these multi-row panoramas quite nicely.

Damn Near Perfect

Back from Beijing, Gabriel Dance of nyt.com puts the viewer there during Sarah Palin's speech at the Republican National Convention. I was struck by this pano in that I can't find a single stitching error anywhere, which is impressive given the situation and subject matter.
I asked Gabriel about the shoot and his gear. Here's his response, which sums up the difficulties of making panos in these situations:

Camera: 5D, 15mm fisheye lens
Rig: ballhead tripod, nodal ninja 5
Stitching: PTGUI Pro
"The most difficult thing about these shots is getting them (which
sounds obvious), but really in these types of situations, as you well
know, all the photogs are trying to get their shots and it's a
balancing act between getting the pano, and not getting shanked by an
angry photog's monopod after blocking their shot. And the space is at
a premium as you can tell from the pano. For this one I was on the
stage left cut-stand and I made sure to get their a good hour before
the shot. Shake hands with the other photographers and let them know
what I'm doing. Let them know that I'll keep my tripod tight and in
my spot. Then, when the time is right, hit the shots as quickly as I
can, making sure not to push/move/lean on the tripod.
And hope for the best...
Then it's some Photoshop, just a little bit of layer blending is
sometimes necessary in case anybody is obviously cut in half, and then
we're done. With these speed is essential. I had this up a lil over
an hour after it was shot."

The embedded audio (recorded by Lisa Tozzi) is an excellent addition.