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Testing a new scope
Posted:
Fri May 22, 2009 7:51 pm
by Big V
Last night the weather allowed for testing of a new 8 inch scope. Each of these shots is 1 hour in length and was taken with a
modified Canon 40D - infra red filter removed and a peltier cooling device attached to it. ISO 800. Given this is only 8 inch in size it performs really well and gives excellent results.
Re: Testing a new scope
Posted:
Fri May 22, 2009 8:05 pm
by radar
Excellent results for sure. Just amazing photos, I never get tired of looking at your astronomy photos.
cheers,
André
Re: Testing a new scope
Posted:
Fri May 22, 2009 8:11 pm
by SuperJT
Very, very nice. How much does it cost to get a camera
modded ?
Re: Testing a new scope
Posted:
Fri May 22, 2009 9:34 pm
by fozzie
Virgs - very nice work as usual. The colours are just amazing
Re: Testing a new scope
Posted:
Fri May 22, 2009 10:49 pm
by DanielA
Great shots Big V.
The first is my pick. It's the best I've seen for colour and framing.
Daniel
Re: Testing a new scope
Posted:
Sat May 23, 2009 1:06 am
by Big V
Modifying the camera cost big dollars - around $2400 all up but it gets you cooling and the ability to record the hydrogen alpha light which is normally blocked by the infra red filter. the company that does this is Korean and their work is outstanding.
http://www.centralds.net/en/index.htm click on products or pricing on the left hand side for further information. One thing to note is for every 6 degrees you cool your camera, you reduce the noise by half. This is why astronomers use cooled cameras as exposures of the lengths we take would normally have a lot of background noise which is not data and in no way enhance the image.
Re: Testing a new scope
Posted:
Sat May 23, 2009 10:48 am
by Marvin
Nice shots Virgs!
Re: Testing a new scope
Posted:
Sat May 23, 2009 10:56 am
by sheepie
Wow - who needs Hubble eh?
Wonderful insights into the world 'up there' Virgs (as usual)
Re: Testing a new scope
Posted:
Sat May 23, 2009 11:11 am
by biggerry
Wow - who needs Hubble eh?
awesome stuff...the
mods to the cameras remind me of overclocking, but for your camera
whats the location (on earth
) of where these are taken? I assume you pick a really nice clear night.
Re: Testing a new scope
Posted:
Sat May 23, 2009 4:24 pm
by Big V
These were taken from Clayton Bay in South Australia, it is about 90 km south of Adelaide near Milang - yes had to wait for a clear night with no moon.
Re: Testing a new scope
Posted:
Sat May 23, 2009 8:20 pm
by johnmc
WOW
they're awesome! and from only an 8 inch scope... that's amazing.
Re: Testing a new scope
Posted:
Sat May 23, 2009 11:16 pm
by chrisk
outstanding V. how does the camera get cooled ?
Re: Testing a new scope
Posted:
Sun May 24, 2009 2:41 am
by Big V
It has a large copper plate at the back of the sensor which is connected to a peltier electronic cooler. If you click on the link to their website it shows a variety of pics which tell the story - very professional finish though - looks like it came out of the factory like it.
Re: Testing a new scope
Posted:
Sun May 24, 2009 4:01 pm
by DanW
These are some great photos.
Big V wrote:Modifying the camera cost big dollars - around $2400 all up but it gets you cooling and the ability to record the hydrogen alpha light which is normally blocked by the infra red filter. the company that does this is Korean and their work is outstanding.
http://www.centralds.net/en/index.htm click on products or pricing on the left hand side for further information. One thing to note is for every 6 degrees you cool your camera, you reduce the noise by half. This is why astronomers use cooled cameras as exposures of the lengths we take would normally have a lot of background noise which is not data and in no way enhance the image.
Having just bought a scientific-use camera, this price could be worse. I paid just over $40,000 a couple of weeks ago for a 1/4MP (that's right - only 1024 by 256 pixels!) cooled CCD. For the money though, it is cooled to about -40 degrees which give awesome sensitivity - somewhere around 20 photons per count (or so I'm told). The power supply for the peltier cooler is about the size of a laser printer and draws close to 10 amps from the wall so it's not what you'd call portable. Still, once its usefulness in the lab has expired, it would be fun to try and take some night shots with it.
Re: Testing a new scope
Posted:
Sun May 24, 2009 8:38 pm
by aim54x
DanW wrote:Having just bought a scientific-use camera, this price could be worse. I paid just over $40,000 a couple of weeks ago for a 1/4MP (that's right - only 1024 by 256 pixels!) cooled CCD. For the money though, it is cooled to about -40 degrees which give awesome sensitivity - somewhere around 20 photons per count (or so I'm told). The power supply for the peltier cooler is about the size of a laser printer and draws close to 10 amps from the wall so it's not what you'd call portable. Still, once its usefulness in the lab has expired, it would be fun to try and take some night shots with it.
Sounds like the Gatan stuff that I have played with at uni attached to TEM's. Apparently they ran out of money when buying new TEM's (JEOL's) so the one earmarked for use biologist has a dodgy 1mp camera whereas the materials science machines have 12mp cameras.
Can I ask what the 1/4mp camera is for?
Re: Testing a new scope
Posted:
Sun May 24, 2009 9:16 pm
by DanW
This one will be attached to a spectrometer for doing what's called "Raman" scattering. Basically when we shine a laser onto a sample of a chemical, some of the light that comes back will have a very slightly different colour to the laser. We use the spectrometer to split the colours apart before sending it to the camera. Then, with a bit of post-processing, we can determine what the chemical was. Unfortunately the Raman scatter is very weak so we have to use some tricky filtering and high sensitivity CCD arrays to pick it out.
aim54x wrote:Apparently they ran out of money when buying new TEM's (JEOL's) so the one earmarked for use biologist has a dodgy 1mp camera whereas the materials science machines have 12mp cameras.
I'm getting WAY off topic now but you've reminded me of my time on JEOLs. Spent much more time on SEMs than TEMs (scanning- and transmission-electron microscopes for those not familiar with the TLAs) but nevertheless, talk about macro! I've got a few images where the magnification is around 500,000X. Sure beats using extension tubes. One of these days I'll have to get around to putting together a gallery of microscope shots.
Re: Testing a new scope
Posted:
Mon Jun 01, 2009 12:25 am
by BBJ
Hey Virgs, Up with your normal standard of this type of pics and very well done mate, i like them all.
Cheers
BBJ
Re: Testing a new scope
Posted:
Mon Jun 01, 2009 8:29 am
by Pa
radar wrote:Excellent results for sure. Just amazing photos, I never get tired of looking at your astronomy photos.
cheers,
André
Re: Testing a new scope
Posted:
Tue Jun 02, 2009 5:17 pm
by DebT
Sensational - and appreciate the technical info...at that price I'll just keep enjoying your wonderful shots - ever thought of doing a calendar on Red Bubble ?
DebT
Re: Testing a new scope
Posted:
Tue Jun 02, 2009 5:29 pm
by gummi
Absolutely stunning Big V, our universe is such a big place - even looking through and 8" scope! Please share more of them if you have em. Can't get over how great those pics are!
Re: Testing a new scope
Posted:
Tue Jun 02, 2009 7:20 pm
by zafra52
Excellent results for sure. Just amazing photos, I never get tired of looking at your astronomy photos.
Same here! They make me feel so insignificant...
Re: Testing a new scope
Posted:
Tue Jun 02, 2009 7:55 pm
by Big V
Thank you for the kind words - as I take them I shall show them. On a side note the Education Department here in SA has selected 5 of my images to turn into postcards for every year 5 student in the state. They are doing a print run of 25,000 cards to give out, so I am very happy to be recognised in this way. My daughter is in year 5 and I think this will give her some bragging rights for a short time...
Re: Testing a new scope
Posted:
Tue Jun 02, 2009 9:13 pm
by DebT
Bugger Karl's only in year 3 ...any chance you can save 1 ?
DebT
Re: Testing a new scope
Posted:
Wed Jun 03, 2009 12:03 am
by Big V
Deb, they are going to give me 10 sets as well as some cash, so yes I shall save you a set...
Re: Testing a new scope
Posted:
Wed Jun 03, 2009 7:18 pm
by zafra52
Congratulations! I bet your kids will be proud of your achievement, and some cash is something is always a help.
Re: Testing a new scope
Posted:
Wed Jun 03, 2009 8:02 pm
by wider
great shots, imagine keeping the unit watertight for the peltier! wooh!
how do you track the stars over that period? or did i miss the point and it is a compilation of layers?
Re: Testing a new scope
Posted:
Wed Jun 03, 2009 11:43 pm
by Big V
Tracking the stars is the job of the telescope mount. It has two motors and is orientated so that one axis is in line with the south celestial pole. As the Earth turns 15 degrees per hour, the motors compensate for this allowing the telescope to keep the stars in the field of view. I use a second smaller scope with a camera on that to lock onto one star and some very clever software records the minute movements created by atmospheric turbulence and inconsitency in the gears of the mount to send minute corrections to the motors. This is known as autoguiding and allows for extremely long exposures whilst keeping the stars nice and round. Got to love new technology - allows so much more to be achieved per night.