Wednesday, January 7, 2009
A New Observatory!
After shooting from very bad location many years I finally have had
a new location for my observatory.
It stil located in very center of the Town and light pollution is a huge problem.
the good thing is, that new place has a good warm room next to the roof dec.
The dec is very well protected from the wind and I have 360 degree free view above 25 degree.
There will be a protective building around the telescope in near future.
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I build a permanent pear for the telescope. It makes a huge difference to my polar alignment
and vibrations. Since I'm using my telescope for photographing only, I made the pier
only 60 cm high. It's very heavy doe the 20mm steal and the actual pier diameter is 200mm.
Here is some images from the new location.
Telescope on the new pier
Canon 200mm f1.8 monster lens on the telescope.
The pier before painting and bolting down.
Leveling is done by the four bolt in the concrete. 
Modification to QHY9 camera
I made a small mod to the QHY9.
There is now angular scale added to the camera.
to be able to read the scale in any position I made it
to move by the gravity. Now I can easily rotate the camera
to specified angle for guide stars when OAG is used or moaic images are made.
QHY9 8,6mb cooled astro camera
My new B&W astro camera is now under testing.
So far it looks like a winner!
Information about the camera:
http://www.qhyccd.com/QHY9.html
The KAF8300 sensor is not known for low noise,
I was litle worried about it.
After first tests I can say, the noise is not a problem.
Cooling in this camera is very good.
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I tested the cooling with ambient temperature of -10C.
It took about 60s. to reach maximum cooling, -60C,
and I was uning about 95% of the maximum cooling power.
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Here is the QE of the camera (The Green line):
Main Features Total pixel : 3448*2574 (8.9mega pixel) Active pixels: 3358*2536 (8.6mega pixel) Pixel Size: 5.4um*5.4um FullWell: 25.5Ke- Imager Size : 19.7*15.04mm 4/3inch Readout noise: TBD(Appox 10e maybe) Preview Speed: 3Mpixel/s (3sec download time) Download Speed: 1Mpixel/s (9sec download time) Peak QE: 56% @540nm 48%@Ha Microlensing on chip ABG: 1000X 16bit ADC with CDS and Preamp USB2.0 High Speed interface Build in 32MBytes SDRAM buffer Support Binning: No Bin, 2*2,3*3,4*4 Communication port to QHY color wheel Improved 2-Stage TEC cooling -50 from ambinet Improved Heat Sink For KODAK CCD Build in Temp sensor and 16bit high presion ADC DC103 DC adapter & TEC Controller, Regulated Build in Mechanical shutter for Full Frame CCD Fully Airproof with Two 4.0mm Air Socket Weight: 510g Deep Cooling DC103 DC adapter & TEC controller Single voltage Input: +12V Output +-15V +5V to CCD PWM TEC controller: 0V-12V to TEC Single Cable connection with QHY2PRO Accquire Temp sensor information For more informations please visit discuss forum http://qhyccd.com/ccdbbs/index.php?topic=989.0
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Some quick and dirty first test images.
Note! NO DARKS are used, only flats and BIAS, 7nm Baader H-alpha filter.
Images are scaled down 50%.
Rosette Nebula. 2 x 10 min with Canon 200mm EF f1.8L lens and QHY9. NO Darks
Extremely dim supernova remnant in Taurus.
Only 5 x 10min Canon 200mm EF f1.8L lens and QHY9, NO Darks
California Nebula, 2 x 10min Canon 200mm EF f1.8L lens and QHY9. No Darks-
Please Note!
Images here are just a very quick test.
The lens was manually focused, and at f1.8 it's not possible to do accuratetly,
all the images are somehow soft for that reason.
No sharpening or noise reduction was used, just stretching.
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The camera has a small pixel size, 5,4 microns.
That gives me resolution of 5"/pixel with 200mm Canon lens.
With 300mm Tokina it will give about 3"/pixel.
Under sampled? yes a litle, but with my seeing conditions not actually at all.
With those lenses I can have both, high resolution and wide field!
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With longer focal lenght, like my LX200 GPS 12", the camera can be binned down 2x2.
It will give resolution of about 1"/pixel. Doe the fact, that the camera has 8,6mb,
image has enough resolution after binning.
Canon 200mm f1.8 lens
My new camera lens is a World fastest telelens, Canon EF 200mm f1.8L.
Here is some information:
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This lens has best difraction limited optical quality I have seen.
Lens is used in SuperWASP project, actually eight of them:
http://www.superwasp.org/
UPDATE
Astronomical images shot with this lens can be seen here:
http://www.astroanarchy.blogspot.com/search/label/Canon%20200mm%20f1.8%20images
UPDATE
Astronomical images shot with this lens can be seen here:
http://www.astroanarchy.blogspot.com/search/label/Canon%20200mm%20f1.8%20images
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The model I bought is electronically focused, so there is no mechanical link between lenses and
focusin ring. After lots of thinking I ended up to modify the lens for the astro work.
Opening up and messing with electronic and mechanic of the expencive lens was not a
easy decision, but it was the only way to use it with my new astrocamera, QHY9.
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Modification:
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removing the original Canon bajonet
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cutting off all the wires between the lens and the bajonet
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soldering an extencion cord between the lens and the bajonet
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attachment of the M42 ,75mm thread to the lens end
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Aftger the modification I can use any EOS Canon body to powering up and adjust the lens
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Images of the modification:
Original wires are cutted and extencions soldered in.
Canon bajonet with cutted wires.
Extencion cords are soldered to the bajonet.
M42 ,75mm thread is attached to lens end.
Allmost ready assembly.
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As you can see from the images I used the lenses filter holder as a route for the cords.
(The canon holder is too small for 2" astronomical filters.)
After final image I wrap some aluminium foil around the lens end to
prevent any light leaks. The foil was then attached with
Black tape around it.
After the modification the lens can be controlled with any unexpencive EOS body.
I build a power source for the EOS body, so there is
no need for the batterys.
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