Another crazy idea. Anyone ever use a pinhole camera and add flash to the scene to cut down on exposure time? Full power on the strobes should help a great deal, even though the flash is only there for a small part of the exposure time. I think it would likely work a bit like some stuff I do working at night. There for some things you can set the exposure for say 15 seconds or so, and then pop the flash from 2 or 3 places during the exposure. A long enough exposure gives you the sense of night and the flash gives you the sharp detail of the image. That is as long as nothing moves. lol
-------- Original Message --------
Subject: Re: making a pinhole
From: Andrew Sharpe <asharpe@xxxxxxxxxxxxxxxx>
Date: Mon, February 07, 2011 11:42 pm
To: List for Photo/Imaging Educators - Professionals - Students
<photoforum@xxxxxxxxxxxxxxxxxx>
I tried a much easier and less expensive experiment. I took a short
extension tube and covered the end with tin foil. I pierced a hole in it
with an acupuncture needle. It was probably f512 (probably an
exaggeration, but it was *small*), and after a rather long exposure
(perhaps 30 seconds -- I was indoors) it worked.
But I'm after rather a better image than the pinhole (or at least, my
pinhole) can produce, so, except for the gratification that I could make
such a lens, I discarded it and went back to my takumars.
Andrew
On 02/07/2011 01:41 PM, Tim Corio wrote:
> 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.)
>> >
>>
>>
>
>
>
--
http://andrewsharpe.com
