Lens Hood for 100mm Filter Holder

I’m one of those sad photographers who always uses a lens hood. I have one for every lens I own, and whenever I’m taking pictures the hood is always on the lens the right way round, unless I’m actually wanting to inject a bit of flare into an image. I’m always amazed when I see people with very expensive pieces of glass on their cameras taking shots with the hood apparently permanently reversed. Why buy …

Tools, Tools, Tools: Electronics

If you’re tempted to build electronics projects similar to some of the ones I’ve described in this blog, there’s no escaping the fact that you’re going to need some tools. Not necessarily a lot of tools, but there are a few things you can’t do without and a few others that will just make your life as a builder a whole lot easier. For building and modifying electronics, the main tools I use are listed …

Make a Pipe Light

One of the surprises from the testing for my post on LED light quality was the spectrum produced by my generic 3W SMT COB LEDs: while not as good as the 95 CRI Nichia LEDs, they looked pretty good considering they cost about 50p each. One other thing in their favour is that they run off a voltage of 3.2 to 3.4 volts. So while my high CRI Nichia COB LEDs may produce a fantastic …

Build Your Own Spectrometer

Not exactly a photography related build, or at least not directly, but if you want to build your own LED lighting and you don’t happen to have a lab with a CRI testing facilities at your disposal, a spectrometer is a useful thing to have around. Whenever you want to check out those bargain LEDs you bought before you commit to building them into a light, stick them in front of this and look at …

LEDs: The Colour of Light

In my previous post I was trying to order my thoughts on how much power I needed for the LED lights I’m about to build. This post is going to look at the quality of that light. For LED lights this is mostly quoted as the CRI, or colour rendering index. This is effectively a measure of colour accuracy and is measured on a scale from 0 to 100. To get a score of 100, …