Note: Images with reduced quality due to file size limits.
International student participating in the Brazilian Scientific Mobility Program (BSMP) at University of California, Berkeley, for the 2015-2016 academic year. Enrolled as a Computer Science Extension student. Born and raised in Rio de Janeiro, Brazil. Undergrad student at Pontifical Catholic University of Rio de Janeiro, studying Computer Engineering and Mathematics. Traditional and Digital art lover and currently interested in Computer Graphics and Artificial Intelligence - but who knows what new field of study I might fall in love with! Trying to learn the most I can during this one year here in Berkeley.
"In this project, you will work in groups of at most 3 to design a pinhole camera. The pinhole camera (also called the "camera obscura") is essentially a dark box with a pinhole on one face, and a screen on the opposite face. Light reflecting off an object is directed through the pinhole to the screen, and an inverted image of the object forms on the screen. The caveat is that it is hard to see the image formed with the naked eye. To be able to see the image, we will use a digital camera with a long exposure time (15-30 seconds) attached to the pinhole camera.
To design a basic easy-to-use pinhole camera, we recommend the following (as taken from the webpage of James Hays):
To capture images:
For this project, you will use three sizes of the pinhole, for instance, .1 mm diameter (really just a pinprick), 3 mm diameter, and 5 mm diameter. Make your design so that you can easily switch between card papers with different hole sizes. These diameters are suggestions: in reality, your pinhole size should be about 1.9 * sqrt(f * lambda), where f is the distance between the pinhole and the screen, and lambda is the wavelength of light (about 550 nm, http://en.wikipedia.org/wiki/Pinhole_camera#Selection_of_pinhole_size). If you use this size, then go a few mm up and down as well to have three pinhole sizes in total. Report what sizes you use on your webpage.
Use all three pinhole sizes to capture two scenes (i.e., you will have six images in total). On your webpage, include an explanation of what happens to the images when you use larger versus smaller pinholes. In addition, capture four other images with the diameter you think did best."
First, I have separated the cardbox that will be used. I have used an old fan box I had. The next step, was to measure the dimensions of the box using a ruler. This will be important for deciding where to place the pinhole and the hole for the camera.
Once I had the measurements, I could start cutting the hole for the camera. I had to make sure that there was not much space to enter light. I used some black tape to help blocking part of the luminosity that would enter the camera.
Then, I needed to make sure that the light that entered the box would not bounce in the walls. For that, I painted the whole box with black paint. To maxmize beauty, I have painted the outside as well.
I have chosen to cut a box where I would place different sizes of pinholes. For controlling the "shutter speed" of the camera, I have prepared a sliding system with cardboard and tape that allows you to block incoming light. For this specific design using a digital camera to capture the image, this feature is not very useful. However, if the camera captured images using photon sensitive paper, it would be necessary to control this shutter. (Well, at least it looks "cool", right?)
Using a very similar style of slider, I have made a system that allows you to change the size of the pihole. With this, you can control the aperture size of the camera. This is very important to adjust how many photons will enter the device. Unfortunately, larger pinholes blur the resulting images.
After that, all I needed was to tape everything together - and BAM! - the camera was READY!
The time has come. Finally I would be able to take my first picture with the pinhole camera. So much excitement invested in such a small moment. I plugged in my camera, opened the aperture the most I could and then pressed the button!
After some time trying to get at least an image from the device, I was able to recognize something in the pictures. Now, I was able to see the lab I was in. The images were still blury but adjusting the shutter speed, the aperture size, the camera ISO and the angle of the box did improve the images. I could not wait to try some "light painting" with the camera - and thats what I did.
It did not matter how much I tried. Images would remain blurry. I would only notice a couble hours later that the closest my camera could focus was 24mm, while my device had 16mm of depth. (ouch!) To fix that I bougth black paper and expanded the box a little bit. After some scissoring and taping, the new box was ready.
After some time adjusting the camera focus, shutter speed, aperture and ISO, finally I was able to get a good image. Image taken from Bancroft Street, next to the International House.
With some help of photoshop dark magic:
For taking the pictures and comparing them, I will be using pinholes of size 5mm, 3mm, 1mm. Special attention should be given to the apperture slider. With this system you can easily switch between different pinhole sizes.
For taking the pictures and comparing them, I will be using pinholes of size 5mm, 3mm, 1mm.
The overall results were pretty good. As expected, the smaller the pinhole the better image quality. Unfortunately, it was not possible to see the effect of "too small" pinholes. It seems that 1mm is still too big for that pinhole camera. In order to take good pictures with the pinhole camera it was necessary to have good lightning. The absence of lens made the pictures too dark, even with high sensor sensitivity and high exposure as you can see in the picture of the dinossaur fossils. Because of increased exposure and ISO, some images had some noise.
A crucial point for taking pictures was focusing the digital camera in the back of the box. This was the key for image sharpness - a very difficult thing to achieve.
On some images you can see a small white square on the bottom right. I found out that it was a light leak and I fixed it by adding a notebook on the top of the device when taking pictures. For taking the pictures it was also necessary to use some cloth (basically, a shirt) to cover the space between the camera and the camera hole.
The dolly zoom effect seemed very interesting. I could not resist giving it a try. The movement was not very smooth but it is possible to see the effect. I had trouble focusing the image while moving, as you can see. Modeling by Roberto Bandeira (friend)
"Me, when I think of pizza" - Bandeira, Roberto