This is the closest to totality that we saw in Bristol during the solar eclipse this morning. Taken on a digital camera, but using a decidedly vintage Tokina RMC 400mm f/5.6 lens with Paragon 2x teleconverter and a custom-made solar filter.Read more "Partial solar eclipse"
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 it […]Read more "Light pollution"
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 them […]Read more "Putting my infrared filters to the test"
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 with […]Read more "Full spectrum camera conversion"
Recently I wrote about making a solar filter for my camera but it’s taken a while to get round to using it. I had a quick go today, using my Canon 450D and a Tokina 400mm f/5.6 lens. The results are a bit iffy – there were massive problems with internal reflections in the lens […]Read more "A new view of the Sun"
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 and […]Read more "Making a solar filter"
I’ve been ill for a couple of days, but today I managed to find the strength to lift this extremely heavy red filter onto this book. It’s an idea I’ve been meaning to try for a few months.Read more "Red heart"