ulf pinhole updategreenspun.com : LUSENET : Large format photography : One Thread
a few weeks ago i posted a question about building am 8x20 or 7x17 pinhole camera. just wanted to let you all know i appreciate your help when i asked about resources and coverage issues .. i will most likely be builidng something in a month or 2 when i find some extra time .. i am going with the idea of a large "tank" below the camera to put exposed film / paper, and some sort of a leaf spring/plate to hold the paper/film, and hold it flat ...it'll be like an oversize mandel-ette post card camera :) when it is made and i have some results from "the beast" i'll post some images online. thanks again & have a nice new year
-- john nanian (firstname.lastname@example.org), December 29, 2001
Why not use photo paper and build a 20"x24" or large pinhole camera?. Why use expensive film when the resolution is limited by diffraction anyway. If you desire to have a transparent negative, which is not really necessary, coat the paper with Canada Balsam as it has the same index of refraction as paper.
-- Phil Glass (email@example.com), December 29, 2001.
what is canada balsam? you are right about using paper. i probably won't use anything fancier than good old rc or fiber paper :) thanks john
-- john nanian (firstname.lastname@example.org), December 29, 2001.
Perhaps the main problem you will encounter in making a panoramic pinhole camera is the light falloff at the far ends of the negative. This could be alleviated by having a curved film plane, which would make the "focal length" the same, at least in the horizontal plane. Of course, then the camera would be a bit unwieldy.
-- Ed Buffaloe (email@example.com), December 31, 2001.
thanks for your suggestions ed :) if my flat exposure-plane gets too much fall-off i'll modify the camera to use a curved one. i am going to be building a 1/2 scale 4x10 camera in the next few weeks and i'll see how things go. from what i understand if my pinhole shim is thin enough and i allow for enough of an image circle i should be okay .. but i'll post my results just the same ! bye for now john
-- john nanian (firstname.lastname@example.org), January 01, 2002.