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Monday, November 19, 2012

Andor Ixon EMCCD on a Ritchie Chretien telescope

Believe me, it is an unforgettable moment to see Her Majesty live! This is the most sensitive camera I have seen so far. Is that thing from this world? Does it come from the future? If you see the Andor Ixon live you will not be able to answer these questions. Maybe the friend of mine, the owner of this marvelous system, could do it.
A cup of fine british tea is next to the Andor. Notice the size of the camera.

The camera sensor can be cooled down to -100°C under the ambient temperature. The Electron Multiplying CCD (EMCCD) has an unheard sensitivity. It enables charge from each pixel to be multiplied on the sensor before readout, providing single photon sensitivity. This approach will revolute  the low light photography as we know it today.
The photography of faint planetary nebulas is in my opinion, a suitable application area of this EMCCD cameras. Since, planetary nebulas are very small and faint, the astrophotographer should use a scope with high focal length (e.g. 5000 mm) and the camera booster on.
The procedure how to capture the star light may be different comparing to the traditional methods, where few long exposures are taken. e.g. 8 exposures of 900s each.
Andors SOLIS (TM) is the dedicated control software for Her Majesty.

Many short exposures are often the case, when working with an EMCCD. e.g. 1000 exposures of 2s each.
The Ixon weights 3.5kg making sturdy focusers inevitable. The big Starlight focuser is suitable for this cam.
I almost forgot to spend some words about it ;-) This is the Ritchie Chretien telescope  collecting the photons for the Andor camera. It has a focal length of 2000mm and focal ratio of f/8, making it probably suitable for capturing Quasars in NIR (near infrared) spectrum. We didn't tested it yet.
The Ixon is connected to the scope via the Baader system ...
...and special customized adapters made by http://www.astroholgi.de. This shop accepts orders and delivers to all european countries.
Impressive: The front view of the RC telescope.
Dust on the secondary mirror absorbs only 1% of the light. Do not clean the mirrors, even they look dirty. Remember: Dust does not reduce the value of your scope. Scratches do it. Dust is removable. Scratches are not.
Many parts of this scope have been improved. The mirrors stayed unchanged.

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Thursday, November 08, 2012

The California nebula in Perseus

Image 1: NGC1499 in Perseus

This is the celestial object NGC1499, the so called California nebula in the Perseus constellation. Since this nebula is larger than the field of view my camera covered, making a mosaic was inevitable to achieve high resolution and depth. This mosaic shown above consists of two parts with 6x900 seconds and 4x900 seconds sub exposures each. The telescope had a focal length of 660mm at f/5.2. A color camera QHY8L (with 7.8mu pixels) was used to capture it. Compared to other similar photos in the net, the high depth of this image is obvious. It is a pure RGB image, not a narrowband composition, so will notice many faint stars in it, being de facto invisible in most narrowband approaches.