- #1
bam707
- 1
- 0
Hello all,
I've been trying to come up with an optical design to basically form images onto a sheet positioned near the ground, in an old camera-obscura fashion. Hopefully this image helps to visualize.
http://www.pinholeblender.com/COimages/mirror.gif
I know that I will require a 45 degree mirror as well as a converging lens to focus the light onto the screen. I got stuck in some of the calculations.
Important points / parameters:
Here is my inspiration: http://www.abelardomorell.net/posts/tent-camera/
The image in this case is projected onto the ground. I plan on doing the same.
Alternate questions:
>> Is a pinhole required to essentially make the incoming light from a point-source? I want to maximize the number of photons actually on the ground.
>> Because the things I am imaging are a far distance, the light would be entering the lens in a parallel fashion, correct?
>> I was thinking of maybe using two lenses, almost as a projector. Off basis?
I appreciate you all, and thank you for your input.
I've been trying to come up with an optical design to basically form images onto a sheet positioned near the ground, in an old camera-obscura fashion. Hopefully this image helps to visualize.
http://www.pinholeblender.com/COimages/mirror.gif
I know that I will require a 45 degree mirror as well as a converging lens to focus the light onto the screen. I got stuck in some of the calculations.
Important points / parameters:
- Imaging things very far away (>100m)
- Distance from lens to screen should be roughly 1.5m
- Magnification needs to produce a final image of roughly 50cm squared (larger is okay)
- Lens diameter should be equal to or less than 60mm, any focal length is okay
- Planning on using an achromatic doublet for wavelength refractive index correction
Here is my inspiration: http://www.abelardomorell.net/posts/tent-camera/
The image in this case is projected onto the ground. I plan on doing the same.
Alternate questions:
>> Is a pinhole required to essentially make the incoming light from a point-source? I want to maximize the number of photons actually on the ground.
>> Because the things I am imaging are a far distance, the light would be entering the lens in a parallel fashion, correct?
>> I was thinking of maybe using two lenses, almost as a projector. Off basis?
I appreciate you all, and thank you for your input.