B 170 (LDN 1149) and B 171 (LDN 1153) Dark Nebulae in Cepheus

Center of field at approximately: RA 21 hours 59 minutes 33 seconds, +58 degrees 56 minutes 08 seconds

Size: 26' x 4.0' and 19' Magnitude: -- and -- Class: 5 Ir and 5 Ir

North is up

West to the right

Telescope:

 8" f5 Newtonian reflector

Camera:

  ST-8XME, self-guided, binned 1x1, temp -15c, camera control MaxIm DL 4.56

Image:

Lumicon Red filter, 860 minutes  (86 x 10 minute subs), 07/25/27/28/29/30/31/2009; seeing 2.4-3.0 FWHM per CCDStack

Processing:

CCDStack 1.6.0.4, Photoshop 7.0

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes:

These dark nebulae are two of several dark patches just north and east of IC 1396. B 170 is to the west of center (right), and B 171 is to the east (left) of center. All three of the fields I imaged were taken mostly in heavy moonlight. See B 173 and B 174 taken during this moon period.

The CDS lists the position of B 170 as 21h 57m 35.9s, +59d 07m 00s ... around the star at the upper right of my image.

These description from the on-line Edward Emerson Barnard "A Photographic Atlas of Selected Region of the Milky Way":

 
170
α(2000)21h 58m 03s, δ(2000) +58 58
Galactic Coordinates 102,+3
 Irregular black strip 26 long NE and SW, 4 wide. This is the northwest border of the island of small stars. It is sharply defined and darker than the sky.
171
α(2000)22h 01m 18s, δ(2000) +58 52
Galactic Coordinates 103,+3
 Irregular broken region, diam. 19, at the E end of the 'island' of small stars

My centering seems to agree with the on-line Chart from Plate 49 ...

From this image on, I will present the native resolution of the ST8 (1530 x 1020 pixels), and a reduced size 1024 pixel width version