Sunday, February 20, 2022

Absent-mindedness and the transmission of light

Another two-hour Populist, at 30mm again. The template had needed some minor adjustments (note the larger shutter) and I felt I still needed more camera-making experience. I chose some thicker-than-normal packaging from cat treats with holiday designs. At the time, I thought the cat on the Halloween theme was funny but with the shutter hole cut out of its back it looks a little distressed.


Concentrating so much on the process, I didn't notice that the cardstock was solid white until putting the template on the back – after completely finishing the front. Well, there will be at least two layers of cardstock and two layers of the template on every surface. Maybeee.....



I finished the camera, loaded it with Arista.edu 100 and put it in the sun so I could tell how bad the light was leaking on an unexposed frame.

While waiting for this test on the first frame, I thought that I could make an informal assessment by shining the light on my iPhone through the material. Here it is compared to the brown cardboard of the Hershey Bar Camera from last week.


That's pretty bad. It barely diffuses the light. But the finished camera will have two layers of template everywhere. If the camera is kept in dim light with the slow film, especially the reciprocity failure-prone Arista, the leakage might be under the film's response level. 


That first frame demonstrated the camera was not remotely light-proof and fogged all the film that had unwrapped off the spool, obscuring half of my first dim light experiment. These first few exposures were hours long but did keep the leakage to a minimum. The second exposure fell victim to what I presume was a cat-tripod collision.



All of these are cropped to one extent or the other. The dim light strategy worked for the most part but the tops of the frame (the bottom of the image) showed streaks in almost all of them. The last dried rose from a bouquet several weeks old.



A selection of small tomatoes segregated by color so you can more efficiently compose your salads.



The exposures were taking forever. By happenstance, the next day was in the 40°s F and heavily overcast. If the camera stayed in the pocket of my black coat and just came out for the pictures, it might be OK.

The trail along Miller's Bay has several low spots that fill with water and reflect the trees.



From nearer shore, looking across to Ames Point on the left and Monkey Island on the right.



More puddles reflecting pines this time.



The parking lot next to the boat launch ramps was completely filled with a giant tent which was in the process of being erected.



At one point the side sagged far enough down so with the tripod extended on it's tiptoes, the camera could get a view of the full extent of the roof.



As I finished that exposure,  a young man came out from under the canvas and we had one of those "Can I help you?" conversations. I told him how cool the curves and textures of his tent were. He said: "You noticed?" The tent was for the Battle on Bago ice-fishing contest and the Polar Plunge. It was walled in with hay bales to stay warm. This fearsome looking machine, which I assume tightens cables, was lying on the ground. I'm surprised a human has enough mass to keep from getting spun around by it,



Looking southeast over Lake Winnebago, at the shanty town about quarter mile off shore, which is just barely at the resolution the pinhole can render.




The pinhole is .20mm. Optimal at 30mm is .23mm.

This is something I have to practice a lot. I started with two sheets of paper under the brass and couldn't get anything smaller than .27mm.  I tried with one sheet of paper. The first two tries were very small and ragged. I made them into nice, smooth but too-large holes trying to enlarge them and then came up with this very good looking .20mm and mounted it on the camera.

The film is semi-stand developed in Caffenol.

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