[at-l] Idea for WOW pic on AT

[bullard@xxxxxxxxxxxx (Jim Bullard)]

Film records whatever light shines on it (within the limits of it's
latitude) for as long as it shines on it. One of the limitations of digital
is that the sensors (at least those used in consumer cameras) don't
"remember" light over long periods of time so exposure isn't cumulative
like it is with film. Many of the photos on AOPD are digital (all of them
from the Hubble telescope and other space based images) but I think they
must be compiling repeated exposures or computer enhancing them. Any
astronomers out there who know how they do that digitally?

At 09:24 AM 3/7/2003 -0600, Shane wrote:
> > http://antwrp.gsfc.nasa.gov/apod/astropix.html
> > Anybody here know how make such a pic on top of say, Wayah
> > or Erect Native American? Or at the Gathering or Trail Daze?
> > It would require cooperation to turn the tents into chineese
> > lanterns, but otherwise it seems doable.
>
>Go to the photography section of the magazine rack in your local book store.
>This picture is on the cover of either Popular Photography or Outdoor
>Photographer this month, and there is an excellent article with other
>pictures like this that explains the process.
>
>It is actually very easy to do, but you need a good film camera that lets
>you have an infinite exposure setting.  Digital will not cut it in this
>case...  You also need a rock solid (read HEAVY) tripod.
>
>Long exposure photographs can also be taken during the day with the right
>film, right exposure settings, and right tripod.  The results are sometimes
>very interesting.  I should dig some of them out and try to scan them,
>although the ones I have are nowhere near as cool as the one you link to.
>
>Digital cameras that allow several seconds of exposure can also be used to
>take some cool pictures.  I have a few of those on a page here:
>
>http://www.theplacewithnoname.com/hiking/images/longexp.htm
>
>Again, these aren't as neat as those possible with a film camera - but it
>gives you an idea.  You should always learn everything you can about your
>camera's capabilities, then experiment.
>
>Shane