Pages

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.

px

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.

Tuesday, October 30, 2012

Observing a communication satellite

Have you ever observed a communication satellite? Read this!

Image 1: An Iridium Flare

{The Iridium satellite constellation is a large group of satellites providing voice and data coverage to satellite phones, pagers and integrated transceivers over Earth's entire surface. Iridium Communications Inc. owns and operates the constellation and sells equipment and access to its services.} [1]

Iridium Flares can be observed without any visual aid. You must be simply in the right place at the right time to observe it. An Iridium Flare can be also easily captured by using simple amateur equipment. The photo above has be taken from a location near Stuttgart, Germany.

Learn how to capture it:

Consult the site http://www.heavens-above.com to find out when an Iridium flare is visible from your site. You need good weather, a very precise clock, a photo tripod (a german telescope mount may be better) and a DSLR camera. You may need six 30s exposures at ISO200 and 28mm focal length. In many cases you will not see anything in the sky, and you may think, you missed the flare. Do not delete your photos! Go home and inspect them on your computer. In most cases, the flare will be in one of your photos!
--
 References:
[1] Wikipedia, The free encyclopedia, http://en.wikipedia.org/wiki/Iridium_satellite_constellation

Monday, October 22, 2012

Jupiter on Oct. 21th 2012 (22:51MEST)

Despite the bad seeing of the last nights, I decided to make some tests on Jupiter, with 5 meters focal length and f/38.4 using my TIS  DBK21 color webcam on a Televue Powermate 5x. The best focal ratio to match this camera is f/28, i.e. 4 meters focal length for 130mm aperture. Hence, I have to use a Televue Powermate 4x instead to get best results. However, the biggest issue here is ... the weather (not the focal ratio).
 Image 1: Luckily, the great Red Spot was visible during the observation

 Image 2: The great Red Spot was easily visible was observable through the scope
  Image 3: The seeing was very bad during that night

 Image 4: Anyway, a low quality photo is better than no photo at all ;-)

Saturday, September 29, 2012

The Flaming Star in Auriga (IC405)

 Image 1: The area around IC405

 Image 2: The Flaming Star in the constellation of Auriga


 Image 3: A huge nebula complex surrounds the Flaming Star

Tuesday, September 18, 2012

Jupiter and its volcano moon Io

Image 1: Jupiter and Io on Sept. 18th 2012, 02:21CEST

This is the hugest gas planet in our solar system. [Jupiter] has more mass than all other planets together. Its volcano moon [Io] is the most active volcanic region in our solar system.
--
References:
Please click on the corresponding hyperlinks

Wednesday, September 12, 2012

Messier 33 - Die Galaxie im Sternbild Dreieck

Abb. 1: Die Galaxie in Triangulum bei 90 Minuten Belichtungszeit

Mit einem scheinbaren Durchmesser von 62" belegt diese Galaxie die doppelte Fläche als der Vollmond am irdischen Firmament. Nur 3.000.000 Lichtjahre von uns entfernt, liegt unsere Nachbargalaxie M33 ein wenig weiter als Andromeda. Halb so groß wie unsere Milchstrasse ist sie und trotzdem kann man ihr schwaches Licht nur in den dunkelsten Herbstnächten beobachten. An ihren breiten Spiralarmen wurden noch nie Sternexplosionen beobachtet; ein Zeichen ihres jungen Alters. Unzählige Sternhaufen, extragalaktische Sternentstehungsgebiete und etliche blaue Riesensterne sind auf hochauflösende Astrofotos identifizierbar.

Abb. 2: M33 Close-Up

Die o.g. Aufnahme dieser Galaxie, auch "Dreiecksnebel" genannt, wurde mit einer Astrokamera des Typs QHY8L bei 660mm Brennweite und Blende f/5.2 gemacht. Eine hochauflösende Aufnahme ist unter http://album.astrodigital.net verfügbar.

Abb.3: NGC604 ist ein Nebel der Galaxie M33
Der Abbildungsmaßstab entspricht hier 2,6m Brennweite und 0,6"/Pixel
Klaren Himmel
Panagiotis
--

Sunday, September 09, 2012

Sun Eclipse on Jupiter on Sept-9th, 2012

 Image 1: Jupiter and Io

This is a Sun eclipse on Jupiter caused by its volcanic moon Io on Sept.9th, 2012 at 1:47MEST. You can see Io and its dark spot on the Jupiter surface, where the Sun eclipse is taking place. This common phenomenon is amazing to observe with an amateur telescope.

Saturday, August 18, 2012

Venus Transit 2012 in Greece

No clouds are in the sky. The deep blue water in the nearby beach is crystal clear. Silence is everywhere. The air is smooth like silk. Colors are in the sky. That's a magic place. The beauty of the greek landscape will be perfect soon. The Venus Transit 2012 is reality.

Image 1: The landscape in Greece before sunrise

Image 2: The Sun looks red due to its low attitude. It is 6:18 o'clock in Greece.
Let's say "hello" to Venus! => "Giasu Aphrodite!" "Γεια σου Αφροδιτη!"

 Image 3: Visual observation using the camera as a telescope

 Image 4: The Venus Transit 2012 in Greece

Image 5: During the "3rd touch" the black drop effect is visible

Image 6: The camera gear used to capture the transit


TIP: Visit my complete Venus-Transit-2012 gallery at:
http://dark.astrodigital.net/venustransit2012

My old Venus-Transit-2004 gallery is also available at:
http://dark.astrodigital.net/venustransit2004

/px

Tuesday, July 24, 2012

Waxing crescent moon

View of the crescent moon shining in the twilight.
Approx. 15% of its surface is illuminated.

Photo: Nikon d3100 at 820mm focal length (f/8).

--
Find more moon photos at: http://dark.astrodigital.net/moon

Tuesday, July 10, 2012

First light AstroProfessional APO 115mm f/7

After the new AstroProfessional 115mm f/7 telescope (Serial No #1533) has arrived, Holger and me decided to make a first light during ... the day. Yes, the Sun were up there and we couldn't wait even a minute ;-). So we mounted his new telescope on a Losmandy G-11 mount and we put my Baader Astrosolar filter on it in order to observe* the Sun. Our neighbor star was very active that week, promising an exciting gazing day :-)
 Image 1: AstroProfessional 115mm f/7 APO on a Losmandy G11 (Gemini)

The AstroProfessional 115mm (f/7) is a air-spaced triplet. It is a full-metal construction, no plastic parts anywhere. The lenses had a greenish coating, the telescope tube was white and stable built. It was securily mounted with two stable tube clamps on the mount. As I observed the Sun through this scope, I remembered the exellent views I had last year with Mike's TMB 115mm, as I observed the Sun from the backyard.
 Image 2: The famous TeleVue Evebrite diagonal on its sturdy focuser

The focuser has a reduction gear. It is well built and beefy. I didn't detect any backlash, so it was already well adjusted in the factory. Let us be honest, it is not a Starlight focuser but it works fine and it does not need to be changed or tuned even for astrophotography.

Markus, a friend of mine, owns a same telescope and he is also very convinced about its capabilities and its overall quality. After inspecting Markus's scope a couple of days later, I had the impression (better said "I was quite sure") that the factory producing this telescope (AstroProfessional) has a well organized test team with competent test engineers, and a serious quality assurance department.

  Image 3: The dew shield is long enough to prevent icing at night

That's funny. The Solar filter shown above (Image 3) has been custom made for my Takahashi FS-102 telescope but it fits also on the AstroProfessional APO :-) The dewing cap of the AP has a smaller(!) diameter than Tak's one.

Image 4: The first photons hitting the telescope lenses are coming from the Sun

Visually, this scope offers sharp views across the field. Is it a TMB? No! I think, it is an AstroProfessional :-) Anyhow, I loved the views through this scope. We were using my japanese Takahashi 7.5mm and 12.5mm LE eyepieces for our observations.

 Image 5: A Baader Astrosolar foil is mandatory for Sun observations.

There is a dedicated 3 inches flattener for this beautiful scope. To be honest, I am not a fan of focal reducers, since most of them introduce chromatic aberrations, and spot sizes having unequal thickness across the field. Also vignetting could be an issue with most reducers if you are working with large camera chips. So I think the best way to work with a scope is by using its dedicated flattener at its native focal length! Hence, if you want to work with two focal lengths, I honestly recommend you to buy two scopes ;-) A short one and a long one :-)

Anyway, I've heard there is a good reducer called Ricardi reducer (click here) able to work with this scope but I don't have any experience with it. For sure the dedicated flattener (click here) gives you the tightest spot size across the field by also keeping most of the optical capabilities of the scope.

Image 6: The Sun
AstroProfessional 115mm (f/7) telescope, Canon 7D, Astrosolar foil
Property of Holger Weber, Germany

The photo above confirms my visual experience I reported above. The Umbra and Penumbra regions of the Sun spots were clearly and with high contrast visible at all magnifications up to 105x. Holger and me were gazing the Sun for many hours before we decided to end our observation session.

Conclusion: I have never observed the Sun so brilliant at this price tag.
This scope is a fun to use and highly recommended.

Thanks for reading.

Panagiotis Xipteras

--
More HiRes shots: dark.astrodigital.net
Manufacturer: AstroProfessional.de

*CAUTION: Use always a special solar filter for your Sun observations. This is mandatory!

Monday, July 09, 2012

Moon photos

 Image 1: The 3rd night after the New Moon (Takahashi FS-102, Nikon d3100)


 Image 2: The Moon with the DSLR (Nikon d3100, 55-300mm Nikkor Tele lense)