This is the second half of a two-part episode. In this half, we talk about the aperture.
Nick and Graham start off talking about the purpose of an aperture on a camera and the collimation of light that is required for a sharp image. Graham floats the crackpot concept of using variously-sized holes in lens caps as aperture controls (10:22). Nick then talks about the optical test-bench he wants to create (14:18).
Returning to the real world from their flights of fancy, they discuss the issues with apertures that get too small and the issues with the wave portion of the particle-wave behavior of light (15:48).
The effects of various numbers of blades in a given aperture are discussed in relation to the holiday movies that make their appearance on The Hallmark Channel (17:47).
Nick describes a lens that uses rotating shutters, rotating apertures, and rotating neutral density filters in a single barrel (29:00).
They discuss what type of aperture each would work with on a quick and simple build (34:32).
Nick talks about a camera he is in the process of designing that uses a dead Fujifilm GX680 body (36:42).
Nick talks about his experience with the Sixty3 plastic panoramic camera that Graham designed and built (49:50) though it takes Nick a bit of time to realize what Graham is hinting at. Graham also discusses another build, the Sixty7 pinhole camera (53:50) made with a Graflok 6X7 back.
This episode was originally planned to cover both the shutter and the aperture but as the recording topped two hours, we decided to separate the two concepts. In two weeks we will continue as we focus on the aperture.
Right off the bat, Graham can’t remember the name of the camera repair guide he read. It’s Camera Maintenance & Repair by Thomas Thomosy.
Contributor to the forums on the Homemade Camera Podcast Flickr group, Flaver-D’s projection-TV-lensed experiment is discussed (12:10) and how having an adjustable aperture is not always very important. Nick brings up the concept that along with shutter speed and aperture, you can use neutral density filters to control exposure as well (12:35).
They discuss the Garbage Cam Build of listener jojonas on Flickr that uses a magnifying glass and black and white printing paper to get some very interesting effect (22:55). They also talk about how the movement of shutters can cause distortions in the image such as the famous forward-leaning race cars from the 1930s (38:25).
The boys try to tackle the concept of slit-scan photography such as that produced by James Guerin, maker of the Reality So Subtle pinhole cameras (41:15).
The Phochron XA shutter tester is mentioned at (58:00) and how it can help with determining the accuracy of settings of older shutters.
Nick reminds us that in the early days of photography the Guillotine was a handy way of creating a consistent shutter opening (1:13:00). Almost immediately afterward they talk about Flickr group member Jonas and his schematic for a shutter that employs magnets from headphones to actuate.
Note: This episode contains some erroneous information about Ilford Direct Positive Paper. Graham states that it is no longer in production. This information is not correct. Direct Positive Paper is still in production after a short interruption. For more information on this, listen to the Sunny 16 Podcast episodes 100a, 100b, 100c where they visit the Harmon Technologies Ilford headquarters.
Nick and Graham talk about lenses and how they can impact a camera build. They talk about why the lens is the most important part of any camera build (5:40) and why it might be a good idea to blend a Debonair lens and a Leica body.
Graham explains why focusing a lens is overrated (18:28) and why you should tape the focusing mechanism of your camera in one position to try out working with a fixed-focus hyperfocal setup. Nick then suggests that the humble mousetrap could provide good functionality to a homemade camera (33:15).
They talk about different methods of attaching lenses to camera bodies including screwing the lenses right to the body and the use of retaining rings for large format lenses (34:10).
The Garbage Cam Challenge has reached its due date and the boys are not as successful in this as they would want to be (53:22). Graham describes his camera made from the discarded paperboard from a 12 pack of soda, a pinhole made from a beer can (56:11) and wooden dowels (INSERT SIZE) that fit tightly in the 135 cartridge reels.
In episode 02, The Body, Nick and Graham talk about the purposes and qualities of a camera body.
Nick talks about exquisite beauty (6:00); the hosts describe the seven components of a camera (14:20); they focus on the body of a camera (19:30); Nick realizes he is late in starting his Garbage Cam Challenge project (24:15); the four main functions of a body are listed (35:00); the guys talk about lens flange distance and how it relates to the body of a camera (46:30).
The second episode (after Episode 00, The Manifesto), Nick and Graham discuss Graham’s creation the FrankenBessa, a camera made from the body of a Voigtlander Bessa 6X9 120 camera and a lens designed for 4X5 cameras.
Graham refers to the K-Pan 6X14cm camera designed by Paul Kohlhaussen as an inspiration for the project. As the FrankenBessa project moved forward, it returned closely to that original inspiration (though in a smaller format) as the final project uses the same hyperfocal setup as the K-Pan.
Later on, Nick introduces the Garbage Cam Challenge wherein each participant creates a camera (pinhole or lensed) from junk laying about the house and uses it for various upcoming photographic assignments. No part of the camera can use a part that was designed for use in a camera with the exception of 35mm film canisters for film transport.