This week our speaker, Simon Weir, treated us to a slightly different talk. The title of the talk was ‘Beyond Visible Light’ dealing with light we cannot see .... ! A slightly strange subject for photographers who strive to show what they have actually seen (altered reality aside!). But we have probably all heard of infrared photography which allows us to ‘see’ the effect of infrared light on the world around us.
First of all let me tell you what infrared photography is NOT! It is not night vision and it is not thermal imaging.
To discover what infrared photography is we were given a quick physics history lesson on the subject. Taking us from Sir Isaac Newton, who was able to show us that white light is made up of every other colour by passing it through a prism and so refracting the light, and William Herschel who measured the temperature of these separated colours. Herschel also discovered he could measure heat from outside what he could see from where he quickly deduced there was some measurable radiation we could not see.
Our lesson progressed on through Robert Williams Wood, an American physicist, for his pioneering IR photography and John Logie Baird for his work in broadcasting using infrared light and the curiously named noctovisor. And then the introduction was made to the electromagnetic spectrum. For those with a technical bent, this shows the wavelength of all the colours in the visible spectrum and those either side of it. Infrared, for those who like number sits at about 750nm (nanometres) - this is very small! But to give this size a bit of 'context' 1nm is 1 millionth of a millimetre which is pretty meaningless unless you are looking for a filter that stops all visible light but passes infrared.
I think that's enough physics for now - unless you want to ask Google for more information!
Simon's talk then brought in some of the proponents of the medium such as music photographer Elliott Landy with his surreal colour infrared images, Simon Marsden who worked mainly in black and white and Richard Mosse who, like Landy, worked in colour infrared but, unlike Landy and his 'psychedelic' world of 60's music culture, specialised in war and conflict. And finally on to the Hubble Telescope and those fantastically clear images of the universe and it's ability to see through and into nebulae and see the stars lurking there thanks to infrared cameras (if stars can actually 'lurk'!).
Again, Google them all.
We now come to the question "how do you take an infrared photograph"? In the good old film days it was easy - you just went to Jessops (other photography outlets were amazingly available) and picked up a roll (or two) of infrared film, treated it with due reverence and loaded it into your camera and away you went. The problems started with the advent of digital cameras and the fact that the sensors which captured the image were already sensitive to the infrared part of the electromagnetic spectrum! To overcome this the manufacturers added a filter over the sensor to block the infrared light. The easy solution is to remove it. However, I somehow think if I were to take apart my camera to remove this filter from it I would get a severe telling off ... !
Fortunately there are places that will do this for you - for a fee. So you pay for your camera - probably second hand because, lets face it, you would want to damage your pride and joy! And then you pay someone some more money to take a bit of it away. And then you can only take infrared images with it!? But you can take lots of them ...
Oh, and Simon Weir does take some very good infrared images - check out his ... well you know what to do!
23 October 2020.