|
Exposure |
SII 150 min. (10 x 15 min. bin
2x2)
Hα
360 min. (24 x 15 min. bin 1x1)
OIII 180 min. (12 x 15 min. bin 2x2)
For the upper image:
Hα
is used
for the luminance
SII,Ha & OIII are mapped
to RGB respectivly |
|
Software |
CCDSoft,
CCDStack, Photoshop CS w/ the Fits Liberator plugin and Noel Carboni's actions.
CCDStack to calibrate, register,
normalize, data reject & combine.
PhotoShop for
non-linear stretching and the color combine. |
|
Comment |
North is to the
bottom... I think it looks better up side down.
The colors in the top
image use the Hubble Palette, with the Hα data used for the
luminance. The lower image uses an "inverted" Hubble Palette. The
SII data is mapped to blue and the OIII to red.
Sprawling across
hundreds of light-years, emission nebula IC 1396 mixes glowing
cosmic gas and dark dust clouds. Stars are forming in this area,
only about 3,000 light-years from Earth. This view of the region is
a composite of digital images recorded through narrow band filters.
The filters actually block out most of the light... but narrowly
transmit wavelengths characteristic of specific glowing atoms in the
nebula. In fact, the color scheme used here makes it easy to trace
some of the elements which contribute to the emission from IC 1396.
In the upper image, emission from sulfur atoms is shown in red,
hydrogen atoms green, and oxygen in blue. The beautiful and useful
result is still very different from what the eye might see. IC 1396
lies in the high and far off constellation of Cepheus.
Source: NASA
APOD
|
