Re: making a pinhole

[Walter Mayes <wmayes1@xxxxxxxxxxx>]

Mark

    Try going to your local hardware store or a machinist supply store and buy some brass shim material. They can be purchased in thickness of just a couple of thousandths thick. They are relatively soft, malleable, easy to work with, can be painted black after you make your hole and can be smoothed with fine emery cloth. I think this would work better then paper, plastic etc.

 

Walter Mayes

   

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.)
>