Deep Southern Orion
. Data - Information - Digital Proc. - Other pics The first pic is the result of 8x 8mins exposures, averaged. Even that the total time is nearly equal to 3x 25mins (64 v/s 75) the result is very different. This is becouse no matter how much we increase the s/n ratio by averaging, the film does not record the same information. Then, what we have to do is to expose always as longer as posible, taking care to let the sky background rech zone III to V. And, of course, we need to the darker location we can. The second pic shows
a previusly made processing. The main differences are the
quality of the scanner (a Polaroid SS35, at 8bits, versus
a Polaroid SS4000 at 12bits) and the method to apply the
pseuso-flat. Here I used substraction instead of
division. See that you can barely see nebulosities aroung
Rigel, wich is not the case with division, where you can
cleary see them. . |
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©2001-2004 Carlos Milovic Fabregat.
questions? comments? Write me at: cmilovic@puc.cl