Instrument

Takahashi FSQ-106ED @ f/5.0 (530 mm F.L.) Captured at 2.1 arcsec/pixel.  Shown at 3.60 and 8.65 arcsec/pixel.

Mount

Paramount MyT

Camera

SBIG STF-8300M Self Guiding Package w/ mono ST-i, using AstroDon 5nm SII, Ha and 3mn OIII filters.

Acquisition Data

9/9/2016 to 10/7/2016  Chino Valley, AZ with CCD Commander & CCDSoft. 

Exposure

Click here for the RGB image
Click here for the b/w Ha image

Software

• CCDSoft, PixInsight & Photoshop CS6.

• PixInsight processing includes calibration, registering, stacking, non-linear stretching with HistogramTransformation .

• Noiseware 5, a PhotoShop plug-in.

• PhotoShop for RGB creation, palette modification and final touch up.

Comment

North is to the top.

This image uses the Hubble palette, where the SII, Ha and OIII data are mapped to the red, green and blue channels respectively. While the OIII data are present throughout the image, they are much weaker relative to the SII and more so to the Ha.

To create the image, the Ha data were reduced and the brightness of the OIII was strongly increased. To bring out more detail, the colors were manipulated with PhotoShop's Selective Color routine. This makes it a "modified" Hubble palette image.

Sh2-171 is about 2700 light-years from Earth in the constellation Cepheus. The emission cloud is lit and ionized by the young star cluster Berkeley 59.

The image also contains six bright and eight dark nebulae as catalogued by Beverly Lynds. After taking a close look, many of the entries seem to be just for the sake of making the catalog larger and have little consequence, if any.