An accurate home-made spherical panorama head
4th November 2005
Specifications & main features
- I/F: Canon DSLR (APS-c sensor size). The design should not preclude other brand from possible accommodation
- Camera & Lens position/orientation in Pitch, Roll and Yaw has is reproducible from one panorama shooting session (after dismounting) to the next session. A script template (PTools or Stitcher 4-5) could then be possibly used.
- Ability to photograph Zenith without obstruction. This applies especially for the Canon EOS 300D (or 20D as well) fitted with the Sigma 8-mm EX fisheye lens.
- The camera can be mounted normally or at a position on the tripod/head that allows specifically to photograph the Nadir (*) from offside position(s). The Nadir area and more than half of the photograph shall then be free from obstruction from tripod or panorama head.
(*)Temporary dismounting/mounting is allowed for this Nadir shoot (Quick release/lock system) without altering repeatability of position.
The presented design was built for the Canon EOS 20D-300D fitted either with the kit lens (for shots at 18 mm focal length) or the Sigma fisheye. Other lenses could be adapted with some minor modification. Partial panorama (HD and multi-rows) possible.
- Mostly aluminum construction. Some parts are made from steel for flexibility, strength, commercial availability or for compactness.
Thus the base plate is made from 9.5 mm thick cast aluminum plate. Most of the rest is made from 6 mm aluminum thick plate, except the Slim rotator sleeve.
- The total weight excluding the "Slim rotator" is 1,0 kg (2,2 US pounds). The vertical wall is the heaviest part that weighs 0.640 kg (1.4 pound). The "Slim" sleeve weighs only 0.1 kg.
- Manfrotto 323 QR (Quick Release) devices are installed in two places. Reversing the orientation of the camera is thus possible for the Nadir shot.
- Possible quick dismounting in four separate main components for compact packing. Mounting and preparation for operation takes only few seconds.
- Natural lateral mechanical play in the QR's was suppressed by tiny screws and lock nuts.
- Positive, accurate and firm stops of the center shaft (yaw control) thanks to the "Slim rotator". The "four notched" model is shown here. Six and ten notches models have also been made (the later is designed for the 18-mm lens: 3 rows of ten photos). The positiveness of the notch makes a sure stop at the next position. Taking one photo per second is feasible (i.e. one row of ten images in ten seconds!)
- The lateral wall and arm (for pitch control) can be set at 0 degree (i.e. horizontal), +60, +90, -30, -60, -90 degrees of elevation. Any other value could be easily accommodated (a hole to be drilled on the vertical wall plate).
- A support plate is screwed on a Manfrotto QR plate to fit below the camera. The camera can be instantly removed or put back on the panorama head .
Tip: Some epoxy was moulded to precisely position and screw repeatedly the camera on the support plate. Moulding was done around the bottom part of the camera by containing the epoxy in plastic transparent film. After polymerization, this was glued on the aluminum support sheet following some trimming and adjustment with a file.
- Conical or conical-hemispherical centering (see illustration) = absolutely slack free design.
- Silky rotation by hand is due to precise constant and adequate pressure applied by a stack of twelve "Belleville" spring washers. Thanks to this pressure, the arm does not naturally rotate under the weigh of the camera: shooting at any elevation (pitch) angle is therefore possible for a given row. This position is not accurately repeatable as there is no pin registration but this makes very high definition multi-rows panorama (telephoto lens) easily feasible.
Clic on picts to enlarge
Detailed photograph of most individual parts can be seen here (older design).
Next step (currently well under way): Sulfuric hard anodization in an home-made electrolytic installation .