Image Acquisition Information
Telescope: 16" RCOS Richey Chretien Telescope (ion milled at 6/9)
Camera: SBIG STL-6303 M
Guiding: SBIG AOL, Astrodon MOAG AOG (SBIG 237
with Custom FLR)
Filters: Astrodon Ha, SII, OIII
Mount: Software Bisque Paramount ME
Acquisition Programs: The Sky,CCDAutopliot III, CCD Soft.
Processing Programs: CCDStack, Maxim DL, Photoshop
Date: July3, 2009 - July 29, 2009
Time: 20 x20 min ( 6.66
hours) each for each of Ha, SII and OIII:
Total of 20 hours imaging time.
Processing: CCD Stack and PhotoShop CS/3
Image Infornmation: Sharpless
2-142 is an emission nebula embedded in the open star cluster NGC 7380, at a distance of about 7200 light years. The
emission nebula (Sh2-142) has been noted to be peculiar in shape and "composed of several bright arcuated clouds, rims
and Hα knots interlaced with local dust lanes" ( Chavarria-K, et al). The nebulosity does have an un usual "scalloped" appearance, as can clearly be seen in this NB image, and it
has been called the Clamshell nebula by some (though this name has also been associated with Sh2-119). This
region contains some 4000 solar masses of gas, primarily hydrogen. The major ionizing star is an eclipsing binary
star DH Cephei). .
Additional Comments: This Narrow Band image was processed using CCDStack, producing a Narrow Band image (Hubble Palatte).
The Narrow Band image was created by an unequal weighting of SII/Ha/OIII at a ratio of 2:1:5 (OIII signal is relatively weak).
This was layered over a modified (enhanced) H-alpha image to bring out some of the details lost in the assembled narrow band
image. The Further data stretching, high pass filtering and background smoothing was performed with Adobe
Photoshop CS/3.