One of the most frustrating problems with using a DSLR camera for long exposure astro-photography is the battery life! Nothing worse than the battery exhausting part way through an imaging session. I resolved this problem at reasonable cost by buying an official Canon DC Coupler DR-400 but saved a lot of money by buying a Maplin 7.5v PSU instead of the Canon version! This is what you need to buy:-
Maplin 3A 3-12v Variable Bench Power Supply Unit reference:- L10BR £19.99 when I bought it
and a Canon DC Coupler DR-400 for £22.00
