Archive for January, 2011

Horse head and Flame Nebulae with SVR90T and H-Alpha Filter

Date: 01.23.2011 (last quarter moon)

Location: San Bruno, CA

Telescope: Stellarvue SVR 90T with Televue x0.8 reducer on Takahashi NJP-Z Mount

Camera: Qhy9 CCD with Astronomik HAlpha 12nm Filter

This is a stacking of 11 exposures of 8minutes.  Even with the short focal ration (f/d 5.6) obtained with the televue reducer, I had to apply 2×2 Binning and take a fair amount of exposure to get details in the Nebula.

The H-Alpha filter does wonder to combat light pollution, even though the FWHM of this filter is not very narrow (12 nanometers).

To capture this picture, I used the software Logme in to monitor the imaging session from the comfort of my living room…

Configuration:

  • Imaging setting outside, connected to my Toshiba Netbook, accessing the Network from a Wireless connexion. The Netbook controls the Qhy9 camera, the Orion autoguider, and the Takahashi NJP-Z mount (Ascom driver).
  • My Laptop, in the living room, allowing remote access to the Netbook using the LogmeIn software.

With long imaging session, getting remote access allows me to check if nothing goes wrong [ issue with tracking, clouds, etc] – without having to check every 20 minutes outside!

Here is a screenshot of the log me in screen with remote access to the Netbook controlling the imaging set up:

Leave a comment

Crab Nebula with C9.25 – Jan 2011

Location: San Bruno, CA

Telescope: Celestron 9.25 with F/d 6.3 reducer on Takahashi NJP-Z Mount

Camera: Qhy8 CCD with Astronomik CLS CCD Filter

This is the result of 16 exposures of 330 sec. The Celestron C9.25 is really a good choice for planetary nebula given its relatively long focal length, and its large aperture.

I find also that many planetary nebula are a nice target when on a light polluted site, since they have a relatively high surface brightness.

What is more important here is to have a night with good seeing conditions,  very good tracking, take multiple shots, and stack!

Software: Maxim DL5, Photoshop CS4, Nik Sharpener

This is a crop of the previous image, showing more details in the Nebula dendrils.

2 Comments

Clavius with Mak Cassegrain 180mm

Date: 1/15/2011

Location: Sam Bruno, CA

Instrument: Orion Mak Cassegrain with Imaging Source DMK camera at f/d 15

Infrared Filter Astronomik IR Pro 742

Processing: Avistack for Image stacking, Astraimage Wavelet processing, Photoshop CS4

Seeing: 3-4/10

The use of the Infrared pass filter (pass wavelength above 742nm)  allowed to pass through the turbulence. Not only the image was much more stable but showed also improved contrast (compared to a regular Infrared Cut filter).

Even if the IR pass filter reduces luminosity, the moon is such a bright object that each frame integration time is still small (1/10 second by frame for this picture – about 1,000 stacked frames ).

Leave a comment

Eskimo Nebula (NGC 2392) with C9.25

Date: 1/5/2011

Location: San Bruno, CA

Telescope: C9.25 on NJP-Z mount

Camera: Qhy8 with CLS CCD Filter

16 exposures of 2 minutes at f/d 6.3.

Processing: Maxim DL5, Photoshop CS4, Astraimage Wavelet filter

The Eskimo planetary nebula has a fairly small angular size:  about 48″,  comparable with the apparent size of Jupiter.

At focal plane, the scale was about 1.15″ by pixel when taking this  image.

Collimation is critical at this focal length – and I made sure the SCT was well collimated.

Given its high surface brightness, shooting NGC 2392 benefits from many short exposures to get the best of seeing conditions, and processing techniques such as sharpening or wavelet filtering.

For this pictures, I tried out my new Losmandy dovetail plate on which the guidescope (Takahashi fs60c) is attached.

I had trouble with tube flexture in the past with other systems to attach the guide scope to my c9.25, but with this great dovetail plate, the guide scope is now coupled to the C9.25 OTA in a very rigid way.

Leave a comment

%d bloggers like this: