The body cap is pretty thick. I would expect a lot of reflections inside the hole causing a foggy look. Also, the long (relatively) hole might cause the image to be constrained to a small circle in the middle of the sensor. Think of drilling a hole in a wall. Look out through the hole, and move side to side. You'll only be able to see a tiny bit of the outside. Now, drill the same sized hole in a sheet of paper. Move side to side. Now you can see a much wider area of the outside. This is all theory. Please let us know how this works out. I'm curious to hear more. Tim On Mon, 2011-02-07 at 21:31 +0000, Christopher Strevens wrote: > Hi. > > > > When I made a pinhole camera many years ago, I used copper strip that > was very thin and placed that over an open box made of cardboard and > pushed a dressmakerâs pin through the copper in the middle. > > > > I used printout paper as the sensitive material then used it as a > paper negative after soaking it in thin machine oil. > > > > I developed it and fixed it normally. > > > > Did you know a film may be developed by rubbing with a human thumb? > > > > As with the box pin hole camera the results are awful. > > > > I also made photographs using copper plates. I cleaned the copper > plate with acetone then washed it with hydrochloric acid washed with > distilled water then dried with acetone. > > > > It was then exposed to light using a lens and a window. > > > > I then plated it with silver by putting it in silver nitrate solution. > It was washed then rinsed with hydrochloric acid and washed again and > then gold plated with gold chloride solution. > > > > I then washed it with distilled water. > > > > All I got was an image of the window in silver and gold. > > > > Later I took a conventional black and white image and exposed the > copper plate with an enlarger. > > > > Eventually I made an image in silver and gold of an unclothed young > women. > > > > Then I was attacked. > > > > Chris > > > > > From: owner-photoforum@xxxxxxxxxxxxxxxxxx > [mailto:owner-photoforum@xxxxxxxxxxxxxxxxxx] On Behalf Of > mark@xxxxxxxxxxxxxxxxxxxx > Sent: 07 February 2011 15:07 > To: List for Photo/Imaging Educators - Professionals - Students > Subject: RE: making a pinhole > > > > > Well I have a drill press and tools so what I was planning to do is > drill the hole directly into the body cap, but don't know if I can > find a bit that small after hearing the discussions. Taking it into > the body cap would give a good clean hole that wouldn't tear up every > time you threw it into a bag like aluminum foil would. Anything > paper, ect would be destroyed the first time you tossed it in the > camera bag. I was hoping for something durable enough that it could > bounce around, be abused by banging into other stuff in a camera bag, > and still be totally functional. > > > > > > The solid material being plastic I might be able to heat a needle and > melt a hole through it. Drilling would give the cleanest hole and I > suspect that would be key. The thickness of the material also could > and likely would be an issue I didn't think about. > > > > > > Rather than aluminum foil, if I glued some cloth over a bigger hole, > fiberglassed over it, painted it flat black, anyone see any problems. > Would be thicker than foil, but likely much much stronger. It would > also be a pain to redo if damaged. Oh well > > > -------- Original Message -------- > Subject: Re: making a pinhole > From: Tim Corio <tcorio@xxxxxxxxxxxxxxxx> > Date: Mon, February 07, 2011 8:17 am > To: List for Photo/Imaging Educators - Professionals - > Students > <photoforum@xxxxxxxxxxxxxxxxxx> > > I played with this a few years ago using my Canon 5D. I cut a > large > hole in a body cap and glued a paper towel tube (painted black > on the > inside) to that. Glued a cardboard disk to the end with a > small > (quarter inch) hole. I painted the whole outside black in > several > layers to fill in a few small light leaks. > > Over the hole in the end of the tube I taped a piece of > aluminum foil. > In that foil I poked a small hole using a pin. > > This gave pretty good results. I could not get a clean hole. > Small > defects in the hole scattered light reducing contrast. > > Body caps are cheap on eBay and the rest of the material is > nearly free. > You can experiment a lot for little cost. > > Tim > > On Sun, 2011-02-06 at 21:43 -0600, David Dyer-Bennet wrote: > > On 2011-02-06 16:20, mark@xxxxxxxxxxxxxxxxxxxx wrote: > > > Came up with an idea. Toyed with the idea of trying some > pinhole > > > photography but something always seems to get in the way. > Came up with > > > an idea to turn a regular film/digital camera into a > pinhole using a > > > body cap. Should work on any 35mm digital ect that would > accept that > > > kind of cap, and an extra cap in the bag weighs next to > nothing and no > > > bulk or extra stuff to lug around. > > > > Would you be shocked to learn they're commercially > available? I have > > one for my Nikon bodies. I've done a tiny bit with it on > digital; I > > should try it on the D700, which should be a bit better than > the DX > > cameras; a bit. > > > > > Now I suspect the smaller the hole the better as far as > sharpness, but > > > is there a group of sizes that I should try? How much of a > difference > > > in hole size should I allow. Granted a body cap isn't > going to alter > > > the GDP, but its not like getting another piece of > cardboard either. Id > > > be interested to hear thoughts and ideas of those with > pinhole > > > experience. > > > > For sharpness, there's an optimal hole size (depends on > distance from > > sensor), and either bigger or smaller loses you resolution. > For > > 35mm-size cameras, going for sharpness is a mugs game, > though; you don't > > get sharp pinhole photography from that small a neg. > > > > (Lots of easy online resources on hold size.) > > > >
