Re: [Frameworks] Extremely Long Exposures - for Months and Years

From: T. Siddle (email suppressed)
Date: Tue Nov 02 2010 - 14:17:25 PDT


I have no idea how one would possibly meter for this, but the one possible
thing I could think to do is use some variation on Victorian methods of
making your own photo-sensitive surfaces (by painting light sensitive
emulsion of one sort or another on paper, glass, or metal, some exposure
times were really long) and then setting up an array of pinhole cameras with
maybe some sort of additional filter to limit light. Alternatively you could
use a very slow negative (or other photo-sensitive surface) and expose it a
little bit each day for a long period of time.

I'd be interested to hear about your results.

Best,
Tessa Siddle

On Tue, Nov 2, 2010 at 11:51 AM, Aditya Mandayam
<email suppressed>wrote:

> I have tested exposures of 1 day, 2 days, 1 week and a fortnight using
> pinhole cameras and paper.
>
> Here is an example of a week long indoor exposure:
> http://farm5.static.flickr.com/4126/5139678697_8552788b30_b.jpg
>
> The pinhole camera had an f-stop of around 250.
>
> This was performed indoors, which allows larger exposure times. Indoor
> long exposures allow much longer exposure times.
>
> I reiterate my question : how would you meter for an outdoor exposure
> over a year?
>
> On Tue, Nov 2, 2010 at 1:35 PM, Elizabeth McAlpine
> <email suppressed> wrote:
> > Some years ago I made a very long exposure still image not nearly as
> long
> > as you are suggesting but it was about 7 hours I found that shooting on
> to
> > duplicating film helped lengthen the exposure it has a very low IOS I
> also
> > used a lot of ND filters on the front of the camera which helped to
> lengthen
> > the exposure time I was shooting in candle light and the print ended
> up
> > having a very red cast I was never sure if it was caused by the candle
> > light or the duplicating film but it worked for my purpose
> >
> > working with pinhole aperture will defiantly increase you exposure times.
> >
> > best
> > Elizabeth McAlpine
> >
> >
> >
> > On 02/11/2010 12:03, "Jason Halprin" <email suppressed> wrote:
> >
> > Well...Long story short, a very long exposure of months or years would be
> > very difficult or nearly impossible to meter for. When you meter for a
> shot
> > you are basing the characteristics of the film on the straight-line
> portion
> > of the characteristic curve - meaning that the film has a more-or-less
> > linear relationship between exposure and density.
> >
> > If you were to expose for months, you would be exposing in the "shoulder"
> > area of the curve, that area where an increase in exposure results in an
> > ever decreasing ratio of exposure to density. Essentially, you are
> working
> > with a situation where most of the possible silver-halide has been
> > activated, and the film no longer has linear, predictable results.
> >
> > Now that that's out of the way, I would propose making your own pin-hole
> > aperture (f64 ? smaller?) and centering this on the back of the lens to
> > lower the amount of light getting to the lens. Also, use a very slow
> > film...and test, test, test. Don't expect a doubling of exposure time to
> > result in a stop of increase in density (it won't be nearly that much).
> It
> > would seem the easiest option would be to rig a cable release on an SLR
> > camera so that you can leave it open, on a tripod, for a very long
> > time...vary your exposure, and take good notes.
> >
> > -Jason Halprin
> >
> >
> > ________________________________
> > From: Aditya Mandayam <email suppressed>
> > To: email suppressed
> > Sent: Tue, November 2, 2010 6:40:11 AM
> > Subject: [Frameworks] Extremely Long Exposures - for Months and Years
> >
> > Hello, I am interested in making extremely long exposures: of the
> > order of many months, perhaps a few years.
> >
> > E.g: http://photoslaves.com/open-shutter-by-michael-wesely/
> >
> > I asked this question on photo.net <http://photo.net> as well:
> > http://photo.net/black-and-white-photo-film-processing-forum/00XKLr
> >
> > I would like to know how to meter for such long exposures. What amount
> > of light does one assume? Average brightness of a day over a year?
> >
> > Thank you.
> > _______________________________________________
> > FrameWorks mailing list
> > email suppressed
> > http://mailman-mail5.webfaction.com/listinfo/frameworks
> >
> >
> > ________________________________
> > _______________________________________________
> > FrameWorks mailing list
> > email suppressed
> > http://mailman-mail5.webfaction.com/listinfo/frameworks
> >
> > _______________________________________________
> > FrameWorks mailing list
> > email suppressed
> > http://mailman-mail5.webfaction.com/listinfo/frameworks
> >
> >
> _______________________________________________
> FrameWorks mailing list
> email suppressed
> http://mailman-mail5.webfaction.com/listinfo/frameworks
>


_______________________________________________
FrameWorks mailing list
email suppressed
http://mailman-mail5.webfaction.com/listinfo/frameworks