Night Vision Astronomy (part 2)
I went back out despite bad conditions: a full moon and a lot of passing clouds.
Even when the clouds would clear up, there were entire constellations I could not see with the naked eye (e.g. Cepheus).
This time, I wanted to try the Aurora Pro with the Maksutov (using the 0.63x FR) and the Baader Zoom.
It was hard to see much in the finder scope, so I started to use the Aurora Pro in front of the finder scope as well. It did help a bit, but moving the Maksutov on the photographic tripods, require two free hands, so it was not very convenient.
Observations with NV and telescope
- Jupiter (no NV needed)
- Mars very close to the Moon (no NV needed): could see both together in the Baader Zoom at 24mm
- Failed to locate/see C1 Polarissima Cluster - Cepheus
- M31 Andromeda Galaxy - very faint
- C14 Double Cluster - Perseus
- Located but could not see M52 Cassiopeia Salt and Pepper Cluster
- M103 Cluster Cassiopeia- located but not much to see
- C10 Cluster - Cassiopeia - located but not much to see
- M45 Pleiades Taurus - not seeing more stars with NV than without (but fainter stars were brighter with NV)
- M42 Great Orion Nebula - a bit of color but not as good as with the Dobsonian
- C41 Hyades Cluster - Taurus
- M31 Andromeda Galaxy
- C14 Double Cluster - Perseus
- Tried to figure out the limit magnitude (got to 6.84) but then more clouds rolled in
Later I figured out the f-stop when using the NV:
f-ratio-telescope * focal-length-nv / focal-length-eyepiece
The Aurora Pro has a focal length of 16mm. So with the Baader Zoom at 24mm, the f-stop is:
5 * 16 / 24 = 3.3
Next time, I should try with the 32 mm eye piece, since it will give me a f-stop of:
5 * 16 / 32 = 2.5
Theoretically providing 3.3^2 / 2.5^2 = 1.73x more light ??