Neat! Dan Matyola http://www.pentaxphotogallery.com/danieljmatyola
On Thu, Apr 26, 2018 at 2:32 PM, Jostein <p...@alunfoto.no> wrote: > > > Den 24.04.2018 20:25, skrev mike wilson: > >> Jostein has a way with Duct tape........ >> > > If you can't fix it with duct tape, you haven't used enough duct tape. :-D > > On that note, and tuning in with the cellphone theme here, I recently > purchased an app for my phone that, provided you cover the lens with duct > tape, will turn your phone into a quite decent dosimeter. > > Apparently it utilises the same effect that had me seriously scared some > six years ago, when I discovered odd streaks of seemingly glowing sensor > dust in long exposure shots with the 645D. And when I looked closer I found > similar black streaks too. Not your ordinary hot pixel, although some were > just dots, one or two pixels wide. And not your ordinary dust either, as > some drew regular spiralling patterns. > > In the 645D case, the sensor was just picking up backscatter of cosmic > rays, shattered and bounced by the Earth's crust; which neatly explained > the black streaks as subtracted noise during dark-framing. > > The app, however, cranks up the ISO to some unknown overdrive and look > specifically for trails made by alpha and beta particles. Thought that was > pretty neat. > > And since there is a known area of Thorium-containing ore an hour's drive > from here, I might now go looking. Duct tape at the ready. :-) > > Jostein > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
