Archive for March, 2011
Monkey Nebula (NGC 2174) with SVR90T in Narrow band
Posted by jmeriaux in Astrophotography, Deep sky objects on March 9, 2011
Location: San Bruno, CA
Telescope: Stellarvue SVR 90T with Stellarvue Field flattener on Takahashi NJP-Z Mount
Camera: Qhy9 CCD with Astronomik H-Alpha 12nm Filter and O-III 12nm Filter
The color picture is a “HOO” Narrowband picture:
- H-Alpha: red channel – 16 exposures of 480secs.
- O-III: green and blue channel – 21 exposures of 480 secs.
On the left, the H-Alpha image, on the right the HOO composite image. Note the Monkey nebula emits mainly in H-Alpha only the central parts of the nebula glows in the OIII band.
Saturn “Serpent Storm” with Celestron EdgeHD 11″
Posted by jmeriaux in Astrophotography, Planets on March 2, 2011
Date: 2/27/2011 at 2.23am PST
Location: San Bruno California
Telescope: EdgeHD 11 with DMK 21AU04.AS Camera and Siebert Barlow 2x
Seeing: 6/10
Image Processing: Frame stacking: AVI Stack, Image composition: Photoshop CS4, Astra Image Wavelet plug-in, Noise Ninja
This is one of the first pictures taken with my new Celestron EdgeHD 11″. The seeing was above average – but not excellent. Visually at x450, Saturn was impressive, with a great contrast on the Cassini division, and details easily visible on the north band (the great north band disturbance famously called “serpent storm”).
The 11″ of aperture here made a huge difference with previous images taken with my Mak Cassegrain 7″, not so much in terms of pure resolution (limited by seeing) – but in terms of image brightness. I imaged at f/d 25 – I should have imaged at f/d 37 with the Mak Cassegrain to achieve the same image scale. I was able to take most of the frames at 1/10 sec. or below, to capture moments of best seeing. This is a composite image made of roughly 2,500 frames shot in about 6 minutes. Capturing Saturn’s satellites up to magnitude 12 on the luminance frame was fairly easy – even though each frame was 1/20sec of exposure for the luminance layer.
Saturn satellites from left to right:
- Dione : magnitude 10.5
- Enceladus: magnitude 11.9
- Rhea: magnitude 9.9
- Thetys: magnitude 10.4
This is a set of three images taken during this imaging session showing Saturn’s rotation…
