AstroTrac
AstroFest saw me treating myself to something I’ve wanted for some time, an AstroTrac. Sunday evening was clear and frosty so I set the unit up on the top of a tripod on the path in front of my house. Leaving the Canon kit 18-55 lens on the 350D I took 10 3 minute exposures of Cassiopia at ISO 400 with the lens set at about 40mm. This produces a huge field of view that takes in the whole constellation down to the Double Cluster in Perseus (lower left of frame) and across to NCG 7789 (mid right).
This type of photograph is very demanding on the lens and the Canon zoom fares badly with lots of chromatic aberration. Looks like I’ll have to invest in some better quality fixed focus lenses.