A 35mm camera, based on the Canonet G-III QL17 rangefinder, simulated in Python.
The purpose of this project is to explore and understand the logic in the mechanisms of a camera by using object-oriented programming to represent real-world objects. It's also a way to appreciate the intricate mechanical logic embodied in a device like a camera.
It aims towards completeness in its modelling of the real world. For example, if you open the back of the camera in daylight with a partially exposed film, it will ruin the film.
See the c is for Camera documentation.
Clone the repository:
git clone https://github.com/evildmp/C-is-for-Camera.git
or:
git clone [email protected]:evildmp/C-is-for-Camera.git
In the C-is-for-Camera
directory, start a Python 3 shell.
>>> from camera import Camera >>> c = Camera()
See the camera's state:
>>> c.state() ================== Camera state ================= ------------------ Controls --------------------- Film speed: 100 ISO Selected speed: 1/125 ------------------ indicators ------------------- Light meter reading ƒ/16 Frame counter: 0 ------------------ Mechanical ------------------- Back closed: True Lens cap on: False Film advance mechanism: False Shutter cocked: False Shutter timer: 1/128 seconds Iris aperture: ƒ/16 Camera exposure settings: Shutter priority EV ------------------ Metering --------------------- Metered light: 4096 cd/m^2 Exposure target: 15.0 EV Mode: Shutter priority Battery: 1.44 V Film speed: 100 ISO ------------------ Film ------------------------- Speed: 100 ISO Rewound into cartridge: False Exposed frames: 0 (of 24) Ruined: False ------------------ Environment ------------------ Scene luminosity: 4096 cd/m^2
Advance the film:
>>> c.film_advance_lever.wind() On frame 0 (of 24) Advancing film On frame 1 (of 24) Cocking shutter Applying aperture value ƒ/1.7 to iris Cocked
Release the shutter:
>>> c.shutter_button.press() Light meter reading: ƒ1/16 Applying aperture value ƒ/16 to iris Shutter opening for 1/128 seconds Shutter closes Shutter uncocked
It's not possible to advance the mechanism twice without releasing the shutter:
>>> c.film_advance_lever.wind() On frame 1 (of 24) Advancing film On frame 2 (of 24) Cocking shutter Applying aperture value ƒ/1.7 to iris Cocked >>> c.film_advance_lever.wind() Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/Users/daniele/Repositories/camera/camera.py", line 163, in wind self.camera.film_advance_mechanism.advance() File "/Users/daniele/Repositories/camera/camera.py", line 178, in advance raise self.AlreadyAdvanced camera.AlreadyAdvanced
If you open the back in daylight it ruins the film:
>>> c.back.open() Opening back Resetting frame counter to 0 'Film is ruined'
Close the back and rewind the film:
>>> c.back.close() Closing back >>> c.film_rewind_mechanism.rewind() Rewinding film