For the Leigh Spinners Mill Centenary Open Day I have turned part of my studio into a large Camera Obscura.
A Camera Obscura is a optical phenomenon in which the rays of light passing through a small hole into a dark space, form an image where they strike a surface, resulting in an inverted (upside down) and reversed (left to right) image of the view outside.
The human eye works much like a camera obscura, with rays of light entering an opening (pupil), being focused through a convex lens and passing a dark chamber before forming an inverted image on a smooth surface (retina).
The earliest known written account of the camera obscura effect was provided by a Chinese philosopher called Mo-tzu (or Mozi) in 400BC. He noted that light from an illuminated object that passed through a pinhole into a darkened room created an inverted image of the original object.
It wasn’t until the 11th century that a viewing screen was used to see the projected inverted image. Alhazen (or Ibn al-Haytham) is said to have invented the camera obscura as we know it today, he carried out experiments with candles and described how the image is formed by rays of light travelling in straight lines.
During previous Spinners Mill Open Days I’ve often been asked why the image on the studio camera ground glass screen is upside down and back to front. Today visitors get to experience that by standing inside what is basically a giant camera. Lets hope it’s a sunny day.
The effect is very much weather dependent and on the position of the sun. Also the smaller the aperture or hole the light passes through then the sharper (but darker) the image, and the larger the aperture, the brighter the image but much softer.
- Please close the curtains behind you, the darker the room the better.
- Let your eyes adjust for a couple of minutes.
- How does it look? Use your mobile phone camera to enhance the view if the weather isn’t playing along.
- Take care it’s dark in there. I have removed the majority of trip hazards.
- Remember to close the curtains tightly when you leave.
Enjoy and please let me know what you think.
Here are some images of the studio space in the lead up to the open day. First tests where the aperture with just a hole a board in the window produced bright but very soft results. I added a simple lens from Bonfoton and it improved greatly.
The studio wall is 7m wide and 3.6m high, its also 5.5m from the window, so a big ask to get a decent result viewable with the naked eye. You can see these mobile phone images enhanced the viewing experience.
The Summer Open Day will be on Saturday 2nd August. The studio will be back as a daylight studio for wet plate collodion photography, tintypes and ambrotypes. Discounted plates of various sizes.