NGC 6939 nebula in Halpha

Full resolution and object identification (1600x1200 px  274kB)

Object data of NGC6939

Object type: open cluster (II 1 r)
Size: 8'
Magnitude: 7.8 mag
Constellation: Cep
Distance: 6,000 Ly

Exposure data

Date: 2005-10-11/12
Location: Schlierbach / Austria (400m)
Telescope: TeleVue NP101 (4" Apo f=540mm)
Camera: ST2000XM with CFW8 and Astronomik Halpha (13 nm)
  Binning: Halpha 1x1
  Exposure time: 15 x 20 min
Exposure time total: 5 h


nebula near NGC6939 is very faint

The nebula is better visible with a clear filter (see LRGB image)