Thanks guys Feroze ----- Original Message ----- From: "Jostein" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, January 11, 2003 5:57 PM Subject: Re: Can digital capture do TIME exposures?
> ...or approaching On Topic: > > >From "A guide for the use of CCD's: #1 Where to start", found by > google at: > http://www.starchaser-obs.com/Ot_art_1.htm > > "Cooling is extremely important. If you use a CCD at room temperature, > thermal noise will add about 150 electrons per second per pixel. A > typical pixel has the capacity for around 150,000 electrons. This > means that in 17 minutes the CCD would be saturated by noise. For each > decrease in 13 degrees F. the production of thermal electrons > decreases by half. Therefore the cooler the unit, the longer the CCD > can be exposed before saturation by thermal noise. Most CCD's have > ThermoElectric cooling (TE). The best is liquid cooling, usually > liquid nitrogen." > > Jostein > > :-) > > > > ----- Original Message ----- > From: "T Rittenhouse" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Saturday, January 11, 2003 2:35 AM > Subject: Re: Can digital capture do TIME exposures? > > > > http://www.skinsite.com/info_liquid_nitrogen.htm > > > > You could have done the google search yourself you know. > > > > Ciao, > > Graywolf > > http://pages.prodigy.net/graywolfphoto > > > > > > ----- Original Message ----- > > From: "Feroze Kistan" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Friday, January 10, 2003 6:28 AM > > Subject: Re: Can digital capture do TIME exposures? > > > > > > > What is the purpose of liquid nitrogen and where is it used? > > > Feroze > > > ----- Original Message ----- > > > From: "T Rittenhouse" <[EMAIL PROTECTED]> > > > To: <[EMAIL PROTECTED]> > > > Sent: Friday, January 10, 2003 1:50 AM > > > Subject: Re: Can digital capture do TIME exposures? > > > > > > > > > > Yep, a little liquid nitrogen will do wonders. > > > > > > > > Ciao, > > > > Graywolf > > > > http://pages.prodigy.net/graywolfphoto > > > > > > > > > > > > ----- Original Message ----- > > > > From: "Jostein" <[EMAIL PROTECTED]> > > > > To: <[EMAIL PROTECTED]> > > > > Sent: Thursday, January 09, 2003 11:40 AM > > > > Subject: Re: Can digital capture do TIME exposures? > > > > > > > > > > > > > I think the ability to do long exposures depends on how much > thermal > > > > > noise the chip produces, and how well it can separate noise > from > > > > > signal. > > > > > > > > > > Dunno the current tech on any particular camera, but I know > astro > > > > > photographers have long embraced digital. However, I think > their > > > > > devices have some serious cooling systems. > > > > > > > > > > > > > > > > > > > > >
