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Tuesday, October 21, 2014

Variable star in the Pelican Nebula



I'll continue with the Pelican nebula tonight, if the weather allows. My goal is to make a two frame mosaic out of this beautiful area.

I made a comparison between my older image from Autumn 2009 and the new one from October 19. 2014.
I noticed a variable star at the image and I made a small animation out of it.

Variable star in the Pelican Nebula, an animation
Click for a large image

Animation between two images, one from Autumn 2009, the other from this Autumn

The whole image of the Pelican Nebula can be seen HERE

The variable star is an Emission-line Star 2MASS J20503695+4421408 

Here is a SIMBAD database report out of it:
http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%4058843&Name=2MASS%20J20503695%2b4421408&submit=submit



Sunday, October 19, 2014

First light for a new observatory



After a long time, a new photography! This is a first light for my new imaging setup and the observatory location. My observatory locates now at middle of the city, next to my home.


There are only 3h of H-alpha filtered light for this first light image of the Pelican Nebula. Original image size was 4096 x 4096 pixels and the image scale is 0.95 arcsecond/ pixel. Field of view is 63 x 63 arcminutes, that's little over a square degree of sky. (A full Moon has an apparent angular diameter of 30 arcminutes, that's half a degree.)

Pelican Nebula, the first light image
Click for a full size view.

This is image shows the emission of ionized hydrogen alone. Exposure time only 3h.

Image above is an uncropped frame, it's stacked from nine 20 min, exposures. Stars are absolute pinpoints from edge to edge! Seeing wasn't very good at the time, FWHM around 3,5 arcseconds. I was very surprised about the image, since the Celestron Edge HD 1100 shouldn't be able to lit this massive CCD 100%. There are some darkenings at corners but the flat frame was able to calibrate it away. Image above is uncropped, just couple of dozens pixels are cut away from sides due to some stacking artefacts.

I have now the 50mm square Astrodon narrow band filters. They are much narrower, than the Baader set I used to have. H-alpha passband is 5nm, the Baader was 7nm wide. Even large difference is with O-III and S-II filters, they both are 3nm wide, the Baader was 8,5nm for O-III and 8nm for S-II.
The narrower passband means more toleration against light pollution, more nebula details and smaller stars.

The 10-Micron mount from Italy is an absolute mechanical masterpiece! Maximum guiding error during a 20min. exposure was about 0,4 arcseconds at both axes. Pointing accuracy is stunning, any target was just middle of crosshair after a slew. 

The Apogee Alta U16 is a finest camera I have ever used! It's very heavy and the CCD is massive, 4096 x 4096, 9 micron pixels. Image below show the size difference between the KAF 8300 CCD-chip, I used before, and the KAF 16803 CCD-chip in my new camera. KAF 8300 is a great CCD but the KAF 16803 is much more suitable for large telescopes with long focal length.



Color images

I borrowed colors from my older wide field image for now. I'll shoot new color channels for this target as soon as the weather permits. I'll also shoot couple of hours more H-alpha lights for better signal to noise.

Mapped colors
Click for a large image, image is little cropped for a visual composition only.


Visual spectrum



A data from this image was used for colors 

The area of interest is marked as white rectangle.

Technical details

Processing work flow

Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack2.
Deconvolution with a CCDStack2 Positive Constraint, 33 iterations, added at 50% weight
Color combine in PS CS3
Levels and curves in PS CS3.

Imaging optics

Celestron Edge HD 1100 @ f7 with 0,7 focal reducer for Edge telescope

Cameras and filters

Imaging camera Apogee Alta U16 and Apogee seven slot filter wheel
Guider camera, Lodestar
Astrodon filter, 5nm H-aplha

Exposure time

H-alpha 3h

Colorimages

Colors are taken from an older wide field image of the area.
The wide field image can be seen here:
http://astroanarchy.blogspot.fi/2011/12/cygnus-mosaic-18-panels-and-22-x-14.html






Monday, October 13, 2014

Cygnus panorama



While waiting the weather to clear, I reprocessed my older material to keep up my skills. This one turned to be so nice. I decided to publish it here.

Cygnus Panorama 
Click for a large image. Note. A largish file, 2400 x 1100 pixels and 3.6MB

A mosaic photo of constellation Cygnus in narrowband colors, R=Sulfur, G=Hydrogen and B=Oxygen. Note. The "noise" at background is not a noise but massive amount of stars!


Labeled 
Click for a large image

Note. A relative size of the Moon is marked at lower Right corner


An original photo and processing, with the technical details, can be seen HERE







Monday, October 6, 2014

A new imaging setup starts to build up.



At beginning of the last Spring season my old imaging setup blew up

During a mandatory Summer pause I have been building a new imaging set up little by little. It starts to be ready mechanically, I need to wait for a couple of clear nights to be able to finalize the setup procedure. 

Without a help from couple of great companies this could be a mission impossible for me.



I have got the most needed help from the beloved neighbour country, Sweden! The Astro Sweden is a largish company specialized to astronomical equipments. They have support my work by equipments and technical knowhow.


Starlight Xpress CCD

I have been using many years some very clever products from the UK based company, Starlight Xpress .
I now have a new Active Optics unit from them, it supports full frame CCD cameras. With the AO-unit I'm using an OAG with the ultra sensitive guider, Lodestar X2. I used to have a smaller version of the AO-unit and Lodestar guider for many years. They really turn any poorly tracking mount to a extremely stable imaging platform. Best of all, the AO-unit works with any third party imaging camera, like the Apogee in my case.


New Setup
click for a large image


Light path

The Active Optics Unit from Starlight Xpress CCD  is attached to a large custom made adapter ring at right.

List of new equipments
  • Mount, 10-micron 1000
  • Optics, Celestron Edge HD 1100
  • Camera, Apogee U16 D09 with KAF16803 chip, 4096x4096 9 microns pixels, 36,8x36,8mm 
  • Filter Wheel, Apogee, seven square slots 50x50mm 
  • Focuser, FeatherTouch with MicroTouch control unit 
  • Heater, Dew Buster 
  • Active Optics Unit, SXV AO LF from Starlight Xpress + OAG 
  • Guider, an ultra sensitive Lodestar X2, also from Starlight Xpress 
  • Focal Reducer, Celestron reducer 0.7 for Edge 1100 (Not yet arrived) 
  • Finder, Telrad 
  • Filters, Astrodon, H-alpha 5nm, O-III 3nm, S-II 3nm. R, G, B and L
I need to wait for a clear weather to be able to finalize the setup. Few things must be done before any imaging is possible. 


To do list

  1. Polar alignment, The axis of the telescope must be exactly parallel to Earth axis 
  2. Collimation, the optical axis must be perfectly concentric 
  3. Fine tune any possible tilt in CCD to have it perfectly perpendicular to light path. 
  4. FocusMax training, ~30 V-curves to have an accurate model of the optical behavior for auto focusing. 
  5. Temperature compensation training, so that temp expansion of the optics can be compensated.