Rooftop Fireball Camera Installation
DFNSMALL and DFNEXT installations in Australia
DFN observatories need to be securely mounted as the images used for calibration can be captured a few hours or days (in the case of a full moon) apart from the actual fireball event. Standalone ground based installation using a stand provides the best stability, but is not always practical due to site constraints or an obscured horizon. Roof mounting can be a convenient alternative in some situations. The observatories must be pointed as close to the vertical as possible, so the incline of the roof will need to be taken into account. The observatories should be bolted into the rafters if possible, not just the roof surface, to minimise wind movements, and (possibly) movement due to thermal expansion of the roof surface.
Roof mounts can be built entirely from parts found from a hardware store. The DFN has successfully used shelving brackets, aluminium angle or square hollow section assembled with bolts and aluminium channel with modular connectors:
DFNEXT installations in Morocco
The observatory has four M8 mounting bolts in a 185x185 mm square pattern.
DXF drawing exports for laser cutting:
- Small DFNEXT/DFNSMALL 2mm aluminium sunshield for cold/moderate climate areas 20170330_Sunshield_2mm_Al.dxf
- Large DFNEXT/DFNSMALL 2mm aluminium sunshield for hot climate areas 20191218_large_dfnext_sunshield_2mm_aluminum.dxf
- Similar with the large sunshield - needs to be bent, see the images above. This new design was improved by adding slits along the bend line, which makes the bending a lot easier in the field.
Securing the Power Adapter
(to be completed) weatherproof box, conduit
Sheet Metal Roof Mount
depending on the results of some analysis of historical pointing stability data, we may design and upload CAD files for a bent sheet metal roof mount at some point in the future