Camera obscura

[Slimnonier]

Hello everyone,

I'm new here and I know very little about photography. I hope my thread won't be too off-topic but I'm pretty sure there are on this forum lots of lighting experts so I try my luck anyway.

I work in a museum where we have this nice big room (30' long, 15' wide, 15' high approx) all painted white inside with windows that display mountains from far away on the other side of a large river (they are kilometers away). This room is unused and I thought about turning that room into a giant camera obscura.

But I fear that the room might be too big for the light source and preventing the camera obscura effect to happen. I know very little about this topic and never tried it before but saw it on the internet.

I know people will tell me to try it by myself to see but my boss won't let me modify that room if I'm not sure it's gonna work...

What are your thoughts about this project?

Again sorry for not being perfectly in topic with that question.

 

[vintagesnaps]

Sounds like a fascinating idea. I remember seeing this some time ago. Camera Obscura Abelardo Morell Morell gives some info. on how he did it.

You might try this company's website. Photo Tools - Camera Obscura - The Old Masters Secret
They don't do anything on a room scale but do camera lucidas for drawing, optical toys, and will be coming out with a camera obscura.

To me it seems rather experimental so maybe there's a way to do it as some sort of learning project? or maybe try it somewhere else first just to get an idea if/how it could work.

 

[vintagesnaps]

You could also do a search on the Alternative Photography site. If you use the Google search box at the top right it comes up with a page with some ads at the top, but skip those and go down to links to the dated articles. I found these.

A camera obscura pilgrimage Open Blog AlternativePhotography.com
Pinhole history History Of Alt. Proc. AlternativePhotography.com

Or you could search articles on the site (upper left) and see what comes up.

 

[gsgary]

Blackout the windows make a small hole and alter hole size to suit

 

[vintagesnaps]

That seems to sum it up! If anything the issue for the museum might be how long the exposure would take and how long the room would be in use. Seems like it could be interesting for visitors to walk through and experience it.

 

[KmH]

If the image is displayed on the wall 30 feet from the aperture, the image will be very faint, because of the inverse square law.
The image will be quite faint even if you use the 15 foot distance, but it will be 4x times brighter than an image on the 30 foot wall.
Once you know which wall the image will be projected onto you can calculate how large a window aperture you will need.

Note too that unless you use an optic in the light path to invert the image, the image from outside will be projected upside down inside the room. An optic in the light path will absorb some of the light too, making the projected image somewhat darker.