Light pollution

Being an city-dwelling astronomer, light pollution is a huge problem for me. Sure, I love the urban convenience of Tesco Extra for emergency overnight bacon but the orange glow of sodium street lights really ruins a night of stargazing. I always drive to my dark site in rural Somerset for “proper” stargazing nights and there itContinue reading “Light pollution”

Putting my infrared filters to the test

I now have three infrared filters and one ultraviolet-pass filter of varying specifications, for different purposes. Two of the IR filters are cheap, one of them was expensive and the UV-pass filter was found in a charity shop and I have no information about it. They all behave differently – so I wanted to test themContinue reading “Putting my infrared filters to the test”

Full spectrum camera conversion

This article is about exploring the world of light our eyes cannot see, using a modified digital SLR camera. I have a physics degree but I’m still finding my way with the practical applications of infrared and ultraviolet, so this article is mostly written from a theoretical point of view. Take everything I say withContinue reading “Full spectrum camera conversion”

Making a solar filter

I wanted a solar filter for my camera, for safe observation and photography of the sun. Typically these filters have an optical density of OD 5.0, which for photographers is ND 100,000. This means that only 0.001% of light is allowed through the filter. You can buy pre-made solar filters, but they are expensive andContinue reading “Making a solar filter”

Photography for beginners: Filters

Filters are pieces of glass that screw onto the front of your camera, and they can cause all sorts of unusual effects to your photos. The good news is that you can buy filters cheaply from eBay (and of course, less cheaply from the high street, if that’s how you like to buy). Before buying,Continue reading “Photography for beginners: Filters”