Post by Steve Rosenow on Jan 17, 2013 4:17:06 GMT -8
As a few of you know (if you've added me as a Flickr contact, that is), I am deep into astronomy. Several years ago I got into it when I bought my first Go-To telescope. At the time I had a 35mm film camera, so I whittled away at some deep sky objects. Of course, I didn't know at the time that in order to have precise photos, the telescope had to be mounted in a polar configuration, so a lot of my early works were scrapped.
After a six year hiatus, I returned to the hobby last summer when I bought an eight-inch Meade Schmidt-Cassegrain telescope with an A/C servo tracking motor and an equatorial wedge and heavy-duty field tripod.
This is the setup. It's fairly heavy, as the telescope's optical tube and base weighs around 60 lbs. The tripod and wedge adds another 50. This particular model was manufactured in the late 1980s and is completely functional. The red keypad is a Push-To guide system that allows me to find any deep sky object with pinpoint accuracy. It's driven by two belt drives attached to optical encoders. The hand controller at the end of the coiled cable is the drive corrector, which I use to correct the telescope's tracking due to periodic error in the drive motor (an inherent design flaw of all telescopes with tracking drives). This allows me to photograph just about anything, for any length of time. It also has a 1/4-20 threaded camera adapter flange so I can run piggyback operation with my camera (which is how I shoot most of the time, since I have a miniature version of my telescope in camera lens format).
Another shot, showing the size in relation to my laptop. The first few subjects I shot were sunspots. I crafted a homemade solar filter out of two sheets of mylar sheeting used for safety blankets, sandwiched inbetween two cardboard rings, which allowed me to shoot the sun in white light.
A set of sunspots taken on July 7, 2012.
Two days later, the sunspot on the far left rotated around a bit further and I shot off a closer shot using a barlow lens and a tele-extender adapter. This increased my focal length considerably. Two days after I shot this photo, this particular sunspot group unleashed a powerful X-class solar flare, sparking northern lights as far south as the U.S./Canadian border with a few days afterwards.
I also shot a few planetary shots. This one, taken on July 10, shows Mars at the last opportunity to do imaging on it in 2012. The next few weeks, Mars got lower in the horizon each night, making imaging work on it impossible.
Saturn. This was shot using two extension tubes and a barlow which doubled my telescope's focal length. Atmospheric clarity that night was superb, alas it was one of the last nights I was able to do any imaging on Saturn. Saturn, like Mars at that time of year, was getting closer to the horizon at twilight. In fact, Saturn and Mars were only a couple degrees apart, situated next to the star Spica, and formed a triangle in the post-sunset twilight skies. After this, imaging Saturn after sunset was impossible.
A shot of Venus, taken in broad daylight. The last week of August saw Venus approach brightness enough to where it would cast shadows in early dawn twilight!
Jupiter. Atmospheric quality and clarity dropped in late summer due to fires, and this was one of the last planetary shots I got. Clarity that night was poor due to an approaching cloud front.
Messier 13 - aka the Great Cluster in Hercules. This was photographed on September 11. This was a single shot. Most of my deep-sky subjects require stacking multiple shots of the same subject instead of one long, continuous exposure. This reduces noise in the photo, and increases the clarity.
NGC 6960, the Veil Nebula. You can barely make it out in this photo (as it sits in a very rich area of stars.
The Dumbbell Nebula.
My first shot of the Great Orion Nebula, taken a week later. This is a total of five minutes' worth of imaging, consisting of eight frames stacked up.
The Andromeda Galaxy.
Messier 45 - the Pleiades (aka Seven Sisters). This is a naked-eye cluster in the constellation Taurus. Visually, it appears as a bright fuzzy patch above and to the right of the constellation Orion. Under extremely clear skies, seven stars become visible to the eye. This was shot with a new lens I'd just got the night before. Three days later, rains set in and never let up, until a couple nights ago. The first shot was about a half hour's worth of imaging. The second (and brighter) image, was another 45 minutes' worth of imaging stacked ontop of the previous imaging data.
After we had our first real clear night in almost three months, I set my sights on the Orion Nebula with my telescope, my Nikon, and my 500mm Schmidt-Cassegrain mirror lens. Last fall I shot data with that lens and kept it aside. Three nights ago I sat out with the telescope gathering approximately an hour's worth of imaging data (6 frames at 10 minutes apiece), then added it ontop of the data I shot last fall.
The next night, I set my sights on the belt stars of the Orion constellation (situated above the Orion Nebula) and focused on the left-most star, Alnitak. That, in turn, led to this.
I waited for the Orion constellation to clear the trees specifically for this attempt and despite waiting outside in sub-freezing temperatures, the wait was very much worth it in the end (I spent most of the time doing visual observing of the Pleiades, and other DSOs in the interim)!
This was a combined total of two and a half hours' worth of imaging data. Since digital cameras cannot shoot long-duration exposures without noise, I bracket each exposure out to a ten minute maximum, then stack them in a program dedicated to astrophotographic image processing. That program brings out the clarity and detail that otherwise would be brought out in a single film exposure. After the stacking is complete, I work the final result in Photoshop.
And last (but not least, as I'll be posting more in this thread), the Whirlpool Galaxy. This is a tricky critter to find as it's very small. It's approximately two full moons' distance off the end of and below the handle, in the Big Dipper asterism.
After a six year hiatus, I returned to the hobby last summer when I bought an eight-inch Meade Schmidt-Cassegrain telescope with an A/C servo tracking motor and an equatorial wedge and heavy-duty field tripod.
This is the setup. It's fairly heavy, as the telescope's optical tube and base weighs around 60 lbs. The tripod and wedge adds another 50. This particular model was manufactured in the late 1980s and is completely functional. The red keypad is a Push-To guide system that allows me to find any deep sky object with pinpoint accuracy. It's driven by two belt drives attached to optical encoders. The hand controller at the end of the coiled cable is the drive corrector, which I use to correct the telescope's tracking due to periodic error in the drive motor (an inherent design flaw of all telescopes with tracking drives). This allows me to photograph just about anything, for any length of time. It also has a 1/4-20 threaded camera adapter flange so I can run piggyback operation with my camera (which is how I shoot most of the time, since I have a miniature version of my telescope in camera lens format).
Another shot, showing the size in relation to my laptop. The first few subjects I shot were sunspots. I crafted a homemade solar filter out of two sheets of mylar sheeting used for safety blankets, sandwiched inbetween two cardboard rings, which allowed me to shoot the sun in white light.
A set of sunspots taken on July 7, 2012.
Two days later, the sunspot on the far left rotated around a bit further and I shot off a closer shot using a barlow lens and a tele-extender adapter. This increased my focal length considerably. Two days after I shot this photo, this particular sunspot group unleashed a powerful X-class solar flare, sparking northern lights as far south as the U.S./Canadian border with a few days afterwards.
I also shot a few planetary shots. This one, taken on July 10, shows Mars at the last opportunity to do imaging on it in 2012. The next few weeks, Mars got lower in the horizon each night, making imaging work on it impossible.
Saturn. This was shot using two extension tubes and a barlow which doubled my telescope's focal length. Atmospheric clarity that night was superb, alas it was one of the last nights I was able to do any imaging on Saturn. Saturn, like Mars at that time of year, was getting closer to the horizon at twilight. In fact, Saturn and Mars were only a couple degrees apart, situated next to the star Spica, and formed a triangle in the post-sunset twilight skies. After this, imaging Saturn after sunset was impossible.
A shot of Venus, taken in broad daylight. The last week of August saw Venus approach brightness enough to where it would cast shadows in early dawn twilight!
Jupiter. Atmospheric quality and clarity dropped in late summer due to fires, and this was one of the last planetary shots I got. Clarity that night was poor due to an approaching cloud front.
Messier 13 - aka the Great Cluster in Hercules. This was photographed on September 11. This was a single shot. Most of my deep-sky subjects require stacking multiple shots of the same subject instead of one long, continuous exposure. This reduces noise in the photo, and increases the clarity.
NGC 6960, the Veil Nebula. You can barely make it out in this photo (as it sits in a very rich area of stars.
The Dumbbell Nebula.
My first shot of the Great Orion Nebula, taken a week later. This is a total of five minutes' worth of imaging, consisting of eight frames stacked up.
The Andromeda Galaxy.
Messier 45 - the Pleiades (aka Seven Sisters). This is a naked-eye cluster in the constellation Taurus. Visually, it appears as a bright fuzzy patch above and to the right of the constellation Orion. Under extremely clear skies, seven stars become visible to the eye. This was shot with a new lens I'd just got the night before. Three days later, rains set in and never let up, until a couple nights ago. The first shot was about a half hour's worth of imaging. The second (and brighter) image, was another 45 minutes' worth of imaging stacked ontop of the previous imaging data.
After we had our first real clear night in almost three months, I set my sights on the Orion Nebula with my telescope, my Nikon, and my 500mm Schmidt-Cassegrain mirror lens. Last fall I shot data with that lens and kept it aside. Three nights ago I sat out with the telescope gathering approximately an hour's worth of imaging data (6 frames at 10 minutes apiece), then added it ontop of the data I shot last fall.
The next night, I set my sights on the belt stars of the Orion constellation (situated above the Orion Nebula) and focused on the left-most star, Alnitak. That, in turn, led to this.
I waited for the Orion constellation to clear the trees specifically for this attempt and despite waiting outside in sub-freezing temperatures, the wait was very much worth it in the end (I spent most of the time doing visual observing of the Pleiades, and other DSOs in the interim)!
This was a combined total of two and a half hours' worth of imaging data. Since digital cameras cannot shoot long-duration exposures without noise, I bracket each exposure out to a ten minute maximum, then stack them in a program dedicated to astrophotographic image processing. That program brings out the clarity and detail that otherwise would be brought out in a single film exposure. After the stacking is complete, I work the final result in Photoshop.
And last (but not least, as I'll be posting more in this thread), the Whirlpool Galaxy. This is a tricky critter to find as it's very small. It's approximately two full moons' distance off the end of and below the handle, in the Big Dipper asterism.
.
