But surely if it is a hot pixel then it will always be hot at that exposure? If it was only hot for one of the two frames then it must have been an error in the data rather than a stuck hot pixel. It is my understanding that the dark frame exposure is the same 'shutter' time as the main shot, so if it is truly hot it should be there too.
> -----Original Message----- > From: Herb Chong [mailto:[EMAIL PROTECTED] > Sent: 16 March 2004 00:55 > To: [EMAIL PROTECTED] > Subject: Re: *ist D Pixel Comparison Test > > > thermal noise will cause pixels to be bright enough to seem > like a hot pixel on a long enough exposure. dark field > subtraction can remove only pixels that hot in the dark > field. if the actual exposure has bright pixels different > from the dark field, they will remain. Photoshop can detect > these and filter them out. the camera could too. > > Herb... > ----- Original Message ----- > From: "Rob Brigham" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Monday, March 15, 2004 6:48 AM > Subject: RE: *ist D Pixel Comparison Test > > > > I must admit I am slightly puzzled - I thought the > in-camera NR (dark > frame subtraction) was supposed to get rid of ALL hot pixels > by removing any hot pixels in the dark frame from the > resultant picture, presumably interpolating a best guess of > what should be there. So why do you get ANY hot pixels with NR on? > > > >
