View allAll Photos Tagged Subframing
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Photographed at Torrance Barrens Dark Sky Preserve, Ontario, Canada (200 km by road north of Toronto)
* Temperature 0° C.
* Total exposure time: 6 minutes.
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Description:
I didn't have enough time before I had to pack up my gear and drive two hours back to my home in the city to make more than six subframes for this photo. I would have liked at least ten. So the resolution is not as good as I'd like it to be, but I think that it's not a bad image.
The Rosette Nebula, which lies about 5,000 light years from Earth, is located just to the east of the constellation Orion, and is in the centre of the (northern hemisphere) winter Milky Way. It can just barely be glimpsed in binoculars from a dark-sky location far away from city lights.
From Wikipedia:
"The Rosette Nebula (also known as Caldwell 49) is a large, spherical, H II region located near one end of a giant molecular cloud in the Monoceros region of the Milky Way Galaxy."
For a version of this photo WITH LABELS, click on your screen to the RIGHT of the photo, or click here:
www.flickr.com/photos/97587627@N06/32743250460
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Nikon D810a camera body on Teleview 101is apochromatic refracting telescope, mounted on Astrophysics 1100GTO equatorial mount.
Six stacked frames; each frame:
* 540 mm focal length
* ISO 3200; 60-second exposure at f/5.4; unguided
(with LENR - long exposure noise reduction)
Stacked in RegiStar;
Processed in Photoshop CS6 (brightness, contrast, levels, colour balance)
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This is a two-panel mosaic of the large California nebula using my 80mm refractor and an Atik Horizon colour camera. This is two stacks of eight-minute subframes, fifteen in total.
Peter
This is the first time I've tried this target with a colour CMOS camera. It was very much a test to see how it would behave pointed at bright stars as some colour CMOS cameras have suffered from reflections and micro-lensing on bright stars.
Normally I rely on mono CCD and CMOS to get the best detail but this is one of the new generation of colour CMOS camera using a Panasonic chip and properly designed to avoid any amp glow. In this image I haven't used flats or darks although I had them available if needed.
The image is a stack of 28 three-minute subframes.
Peter
Equipment:
Atik Horizon CMOS colour camera, 80mm triplet APO, EQ8 Mount.
Technically Messier 16 is the star cluster in the centre of this image and was one of the early night sky targets distracting Charles Messier in his hunt for comets. It is now better known as the Eagle nebula for the dark bird-like shape in the nebulosity surrounding the cluster. The Eagle shape itself is thanks to the famous Hubble telescope image now more commonly known as the central part of the pillars of creation.
This is a stack of eleven five-minute subframes taken through my 300mm f/10 SCT using an Atik Horizon colour CMOS camera.
Peter
This is a look in Hydrogen Alpha at the intriguing 'Bubble' nebula, NGC 7635. This image is a stack of eleven eight-minute subframes.
Peter
Equipment:
Atik 460EX CCD, Ha filter, 14inch f/10 LX200 SCT, EQ8 mount autoguided with a Lodestar Mk2 off-axis guider.
Seen on Gt. Yarmouth seafront.
Frame: Steel trellis, cast aluminium rear subframe
Length: 86.6 in. (2,200 mm)
Height:
Width:
Wheelbase: 63.58 in. (1,615 mm)
Seat height: 29.72 in. (755 mm)
Dry weight: 485 lb. (220 kg)
Curb weight: 544.5 lb. (247 kg)
Front suspension: Adjustable 1.97 in. (50 mm) fork
Rear suspension: Single shock absorber
Front brake: Twin 12.6 in. (320 mm) discs, ABS
Rear brake: Single 10.43 in. (265 mm) disc, ABS
Front tyre: Pirelli Diablo Rosso II, 120/70 ZR17
Rear tyre: Pirelli Diablo Rosso II 240/45 ZR17
Fuel capacity: 3.96 gal. (18 litres)
Engine: 1,262 cc, (77 cu. in.) Ducati Testastretta DVT, L-twin, four stroke, fuel injected, liquid cooled
Engine output: 152 hp (110.9 kW) at 9,500 rpm
Gearbox: 6 speed constant mesh
Top speed: 169 mph (272 km/h)
The Trifid nebula (M20/NGC 6514) at top with the huge Lagoon nebula (NGC 6523) below with several smaller HII regions over at bottom left.
This picture is a mosaic of two panes, each pane being an integration of multiple subframes shot with a William Optics Zenithstar 103 scope and QHY168C OSC camera; an STC multi-spectra LP filter was used. The upper pane is an integration of 236 x 180s frame, the lower pane is 183 x 180s.
Imagiing was managed via Sequence Generator Pro and PHD2, all post-processing was carried out in PixInsight.
Observed from Prachinburi, Thailand
This is a relatively short stack of eight 480 second subframes (plus flats and darks) taken with a one-shot colour camera before the inevitable cloud moved in this evening (25th February). M97 was nicknamed the 'Owl' when Lord Rosse first observed it with one of his large telescopes at Birr. It was discovered by Pierre Mechain, Charles Messier's assistant and colleague, who added most of the later Messier catalogue items. Curiously, Messier's catalogue was actually a compilation of objects that they didn't want to be distracted by and mistake for a comet!
Below and to the left edge of M97, partly obscured by a star in our galaxy, is faint magnitude 16 galaxy PGC 34279.
Peter
Equipment:
ZWO ASI071 MC Pro CMOS camera, Baader S narrowband filter, 356mm f/10 LX200 SCT, EQ8 mount. Autoguided off-axis with a Lodestar X2 CCD.
A double portrait using two different smartscopes.
Left: Dwarf 3 | 210 45-second subframes
Right: Seestar S50 | 472 10-second subframes
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Photographed at Algonquin Provincial Park, Ontario, Canada
(285 km by road north of Toronto)
between 23.55 Aug. 1 and 00.11 EDT Aug. 2
* Altitude of centre of frame at time of exposures: ~70°
* Temperature 17° C.
* Total exposure time: 8 minutes
* 105 mm focal length lens
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Description:
High in the northern hemisphere summer sky, the gossamer band of our Milky Way galaxy passes through the constellations Cepheus (to the left) and Cygnus (to the right). This area of the sky is rich with red-pink clouds of glowing ionized hydrogen gas, as well as numerous star cluster and foreground clouds of dark gas.
The distinctively shaped north America Nebula in Cygnus appears in the lower right. The large gas cloud IC 1396 in Cepheus is in the opposite corner. At the upper left edge of IC 1396 is Herschel's Garnet Star, with its striking ochre-orange colour.
For a version of this photo WITH LABELS, click on your screen to the RIGHT of the photo, or click here:
www.flickr.com/photos/97587627@N06/48527625751
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Technical information:
Nikkor AF-S 70-200 mm f/2.8 G ED VRII lens on Nikon D810a camera body, mounted on Astrophysics 1100GTO mount with a Kirk Enterprises ball head
Eight stacked subframes; each frame:
105 mm focal length
ISO 6400; 1 minute exposure at f/4.5, unguided
(with LENR - long exposure noise reduction)
Subframes stacked in RegiStar;
Processed in Photoshop CS6 (levels, brightness, contrast, colour balance)
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The Lagoon Nebula (M8) and The Trifid Nebula (M20) in the constellation Sagittarius, just north west of the center of the Milky Way. The Lagoon Nebula is a giant star-forming region while The Trifid Nebula is a combination of an emission nebula (red), a reflection nebula (blue) and dark nebula (brown-black regions dividing the emission nebula into three parts). I was only able to capture 11 x 10' subframes before the field of view got too low in the sky and the sun started to rise. Captured using an AT65 refractor, an SBIG ST4000 XCM camera at -5 C and a Losmandy G 11 mount on July 7, 2016.
Spiral Galaxy in sculptor
Taken at home (Santiago de Chile)
GSO RC 12" on top of a Mi250 mount
Atik383L camera - filter wheel and astrodon filters
ACP-Maxim-focusmax for capture PixInsight for processing
RGB(10h,11h,12.5h) in 10 min subframes
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Photographed from mid-town Toronto, Canada, at 18.43 EST (Moon altitude: 57° | Sun 14° below the horizon)
* Temperature 4° C.
The sky was reasonably clear, with some thin cirrus cloud, when I was able to get the ten base subframes that make up this view of the Moon high over Toronto early on this mild January evening before the heavier cloud moved in.
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Nikon D850 camera body on Explore Scientific 152 mm (6") apochromatic refracting telescope, mounted on Sky-Watcher AZ-EQ6 SynScan mount.
Best ten of fourteen identical stacked frames; each frame:
* ISO 100, 1/120 sec. exposure
Stacked in Registax
Processed in Photoshop CS6
(brightness, contrast, sharpening on right side of Moon)
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IC 4592 is a large blue reflection nebula lit by the light from the multiple star system ν Scorpii - the brightest star in the frame, just below center.
This photo is another framing failure - the nebula is commonly known as the Blue Horsehead but I have truncated the horse's muzzle (at bottom right). It needs a wider field of view, or a mosaic - I'll maybe try again next year.
Anyway, this image is an integration of 211 x240s subframes captured on a QHY168C OSC with WO Zenithstar 103 scope. An STC multispectra LP filter was used. Imaging was controlled via SGP and PHD2, all post-processing was with PixInsight.
Observed from Prachinburi, Thailand
Manufacturer: Auto Union AG / August Horch Automobilwerke GmbH, Zwickau - Germay
Type: 853A Sport Cabriolet
Engine: 4944cc straight-8
Power: 120 bhp / 3.400 rpm
Speed: 135 km/h
Production time: 1938 - 1939
Production outlet: 342
Curb weight: 2631 kg
Special:
- The basic 853 is designed by Horch chief-designer Günther Mickwausch.
- The 853A differs from the 853 through the shortened frame (5 cm) and a renewed subframe to support the radiator. This was done, so other coachbuilders (like Gläser, Baur, Erdmann & Rossi, etc.) could put on easier a Convertible or Coupe.
- The 853A also had a new engine with 120 bhp (instead of 100bhp), a renewed front, a new front suspension with double wishbones and used a DeDion axle rear suspension.
- The most beautifully styled Sport Cabriolet of their era was although expensive, they were cheaper than their Mercedes-Benz rival, the 540K.
- Auto Union was comprised of Horch, DKW, Audi and Wanderer since 1932.
- It has a four-speed manuel gearbox with overdrive by ZF.
- This automobile could be delivered in the colour "Fischsilber" ("silver fish"), a metallic paint in four colours (contained finely ground fish scales).
- When World War II began, production of the Horch Automobiles ceased.
Added to the gallery www.flickr.com/photos/stevepoe/galleries/72157639107186833
Another nice wintertime deep space object to photograph, the Rosette Nebula in Monoceros. It's advertised as 5200 light years from Earth, and the star cluster within it is estimated to be only 5 million years old. It's still just a baby!
TMB 80mm f/6.3 refractor, TV 0.8x field flattener/reducer, ASI533MC Pro, 30 120-second subframes with a dual narrow band filter. Calibrated with darks, flats, etc. Post-processed with DSS and PS.
February 3, 2025, backyard, Tallahassee, Florida. Bortle 7 suburban sky. Seeing was good though transparency was average to poor with high altitude cirrus clouds passing from west to east. Guiding was poor because I was too lazy to do a proper polar alignment.
Many people see religious imagery in clouds, reflections, toast, and rust stains on the side of buildings, among many other things. In that vein, I call this image, "Laughing Jesus." Watch out for the holy spittle! I imagine that He just tricked Satan into pulling His finger.
A mystery hides within 20 of the subframes within this image. I will reveal the oddities as I organize a good way to present them. I'm not saying they are unidentified aerial phenomena or aliens, but they do indicate a mystery object not recorded in satellite catalogues.
Dwarf III. 286 45-second subframes. Polar alignment.
Breakdown of follow up images:
www.flickr.com/photos/glenbledsoe/54829978059/in/photostr...
www.flickr.com/photos/glenbledsoe/54829738721/in/photostr...
www.flickr.com/photos/glenbledsoe/54830006013/in/photostr...
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Photographed at Algonquin Provincial Park, Ontario, Canada, between 00.37 and 01.12 EDT
(285 km by road north of Toronto)
* Altitude of nebula at time of exposures: 63-58°
* Temperature 2° C.
* Total exposure time: 15 minutes
* 660 mm focal length telescope
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Description:
This huge ionized hydrogen gas cloud lies about 2,400 light years from our solar system. The nebula itself is named Sharpless 131; the large open cluster of stars near its centre is cataloged as IC 1396 or Trumpler 37. Below and to the right of centre is a small, prominent globule that is often referred to as the "Elephant's Trunk Nebula" (IC 1396a), and is an active star-forming region.
Here is another view of this object, made with a slightly smaller telescope almost exactly one year ago:
www.flickr.com/photos/97587627@N06/36698969403
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Technical information:
Nikon D810a camera body on Tele Vue 127is (127 mm - 5" - diameter) apochromatic astrograph, mounted on Astrophysics 1100GTO equatorial mount
Fifteen stacked subframes; each frame:
ISO 8000; 1 minute exposure at f/5.2, unguided
(with LENR - long exposure noise reduction)
Subframes stacked in RegiStar;
Processed in Photoshop CS6 (levels, brightness / contrast, bright star flare reduction)
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Photographed 20 km south of Katherine, Northern Territory, Australia
(300 km southeast of Darwin, at latitude 14.5 degrees south)
* Total exposure time: 9 minutes.
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Description:
This is an ultra wide-angle view of or home galaxy - the Milky Way - in the opposite direction to the centre of the galaxy in the constellations Sagittarius and Scorpius. This part of the Milky Way is not often photographed, and is challenging because it is fainter than the other half of the galaxy.
The nine subframes that were combined to form this image were captured between 04.31 and 04.51 CAST (Central Australian Standard Time), ending half an hour before the start of morning twilight.
Here is the equipment used to make this image:
www.flickr.com/photos/97587627@N06/21202535154
In this view we see the following:
* Upper left: The tight cluster of bright stars is M45 - the Pleiades - in the constellation Taurus (the Bull). At the left edge toward the top is the oblong, deep red gas cloud known as the California Nebula.
* Centre of the frame: The familiar star pattern of the constellation Orion (the Hunter) dominates this part of the photo. Several red hydrogen gas clouds can be seen here, including the semi-circular Barnard's Loop.
* Centre right: The brilliant star Canopus, in the constellation Carina (the Keel), is near the right edge of the frame. It is the second brightest star in the sky, outshone only by Sirius (the Dog Star), which appears just below and to the right of centre in this photo.
* Lower right: In the constellation Vela (the Sail) we see large red hydrogen gas clouds that are not often shown in long exposure astrophotos.
* Centre bottom: The zodiacal light is a pyramid rising from the horizon in the hour before morning twilight starts.
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Technical information:
Nikkor AF-S 14-24 mm f/2.8G ED lens on Nikon D810a camera body, mounted on Sky-Watcher Star Adventurer tracking mount with a Kirk Enterprises ball head
Nine stacked frames; each frame:
14 mm focal length
ISO 4000; 1 minute exposure at f/4
(with LENR - long exposure noise reduction)
Stacked in RegiStar;
Processed in Photoshop CS6 (brightness, contrast, levels, colour balance)
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The North America Nebula, NGC 7000 is an emission nebula in the constellation Cygnus, close to the star Deneb. The Nebula covers a region more than ten times the area of the full moon, but its surface brightness is low, so normally it cannot be seen with the unaided eye. The portion of the nebula resembling Mexico and Central America is known as the Cygnus Wall. This region exhibits the most concentrated star formation.
Skywatcher 8" f4 Quattro reflector
Skywatcher EQ6-R Mount
ZWO ASI2600MC Duo main camera
ZWO ASI 120MM Guide Camera
Optolong L-Pro filter
16Hrs of integrated 3min subframes captured over four nights
Pixinsight and Adobe PS
1991 Ford Escort 1.3 Popular estate.
Ex-BT?
Scrapped.
Last MoT test expired in August 2017.
It failed a test that month -
Nearside battery insecure (1.9.1)
Nearside rear seat belt cut sufficient to obstruct correct operation of the belt (5.2.2a)
Offside fuel cap/sealing device does not fasten securely maintaining the sealing arrangement (7.2.4b)
Nearside headlamp aim too high (1.8)
Offside headlamp aim too high (1.8)
Exhaust has a major leak of exhaust gases rear box (7.1.2)
Parking brake lever has no reserve travel (3.1.6b)
Nearside front suspension arm rubber bush deteriorated resulting in excessive movement both bushes (2.4.g.2)
Offside front suspension arm rubber bush deteriorated resulting in excessive movement (2.4.g.2)
Nearside front suspension spring mounting prescribed area is excessively corroded battery tray (2.4.a.3)
Nearside rear suspension spring mounting prescribed area is excessively corroded inner arch (2.4.a.3)
Nearside front subframe mounting prescribed area is excessively corroded outer sill (2.4.a.3)
Nearside inner seat belt anchorage prescribed area is excessively corroded sill by b-pillar (5.2.6)
Offside outer seat belt anchorage prescribed area is excessively corroded sill (5.2.6)
Offside rear seat belt anchorage prescribed area is excessively corroded floor (5.2.6)
The ongoing re-development on West Quay Road (the waterfront-291 luxury flats).
For this week's Flickr Friday theme "sub framing" a Poole 27.07.2023
Manufacturer: Carl F. W. Borgward G. m. b. H. Automobil- und Motoren-Werke, Bremen-Hastedt -Germany / Carl F. W. Borgward G.m.b.H., Bremen-Sebaldsbrück - Germany
Type: BO 611 Omnibus
Production time: 1959 - 1961
Production outlet: 14,748 (all B 611 Series)
Engine: 1493cc straight-4
Power: 60 bhp / 4.700 rpm
Torque: 108 bhp / 2.400 rpm
Drivetrain: rear wheels
Speed: 92 km/h
Curb weight: 1740 kg
Wheelbase: 102 inch
Chassis: steel ladder-frame + additional subframe with all-steel body
Steering: ZF-Gemmer worm & sector
Gearbox: four-speed manual / fully synchronized / steering wheel shifter
Clutch: hydraulic F&S single dry plate disc
Carburettor: Solex 32 PJCB
Fuel tank: 50 liter
Electric system: Bosch 6 Volts / Diesel 12 Volts
Ignition system: distributor and coil
Brakes front: hydraulic Duplex inside expanding drums
Brakes rear: hydraulic Simplex inside expanding drums
Suspension front: independent two unequal length laterally mounted wishbones, sliding struts with coil springs and sway bar + telescopic shock absorbers
Suspension rear: transverse reinforcement bars with sliding struts, longitudinally mounted semi-elliptic leaf springs + telescopic shock absorbers
Rear axle: rigid "swing" Banjo type
Differential: spiral bevel
Wheels: 4 1/2 K x15
Tires: 6,70 x 15
Special:
- This light commercial vehicle was launched in 1957 as Borgward B 1500 F (F="Frontlenker-Transporter" / "Cabover Transporter") and renamed in 1959 as B 611.
- The engine was installed in a large pod between the driver and his passenger.
- The Omnibus has a 17 passengers capacity and with a relatively narrow turning circle of 10.8 meters it was particularly suitable for city use.
- The B 611 Series was available as this BO 611 Omnibus, as B 611 Van, as B 611 Pick-Up Truck and as rolling chassis cab.
- It also could be bought as D/B(O) 611 with a 1758cc straight-4 Bosch PES 4 A 50 B 410 RS 80/1 Diesel engine - 42 bhp / 3.400 rpm - 102 Nm / 2.200 rpm - 75 km/h.
- According to the owner this bus is in totally original (unrestored) condition and there are only 4 Omnibus survivors left.
Comet Lovejoy, January 12, 2015. This is 11 300 second subframes stacked for each of red, green, and blue channels, for 2.75 hours of total imaging.
I'm no expert at comet photography, but as a novice, I'm happy with this result.
1998 Alfa Romeo 145 1.6 T. Spark.
Last taxed in September 2008 and last MoT test expired in August 2007.
It failed a test in July 2012 -
Horn not working (1.6.2a)
Windscreen washer provides insufficient washer liquid (8.2.3)
Nearside Front Lower Suspension arm has excessive play in a pin/bush (2.4.G.2)
Nearside Front Subframe mounting prescribed area is excessively corroded (2.4.A.3)
Offside Front Subframe mounting prescribed area is excessively corroded (2.4.A.3)
Nearside Rear Shock absorber has a serious fluid leak (2.7.3)
Nearside Rear Shock absorber has negligible damping effect (2.7.5)
Nearside Rear wheel bearing rough when rotated (2.6.1)
Offside Seat belt anchorage prescribed area is excessively corroded (5.2.6)
Nearside rear parking brake recording little or no effort (3.7.B.6a)
Parking brake: efficiency below requirements (3.7.B.7)
I took this image just at the end of astronomical dark on April 10,2021 in the Gila National Forest, New Mexico, USA.
The Lagoon Nebula is about 5200 light years from Earth. It is the remnant of an exploded star and as such is a new star forming region - look at all those young (1-2 million years) hot white stars recently formed through gravitational coalescence near the center of the magenta colored cloud. The nebula is an emission nebula, meaning it emits lots of light at the Hydrogen alpha wavelength of 656 nm in the deep red. Other emission lines in the blue from oxygen, mix with the red to make a brilliant magenta. The emission is produced when ionized atoms recombine with free electrons. The atoms become ionized (or driven into an excited state) by ultraviolet light emitted by one or a few of the brighter stars. One in particular, 9 Sagittarii, is nearly 25,000 times brighter than our Sun. The Lagoon nebula is one of several great examples where we can see the life cycle of stars in one image. BTW that’s the Trifid Nebula in the upper right part of the image.
If you can find a really dark place, it is just barely visible to the naked eye ( I was able to see it after the core of the Milky Way was up). It is easily seen in binoculars or a small telescope but still appears gray since the most sensitive part of our retinas don’t see color. It is often seen in wide angle night scape photos of the Milky Way over the landscape and can be easily photographed with a tripod, a normal camera lens and a few seconds of exposure. Look for a purple region.
Photo info: Subframe images collected the early morning hours of April 10, 2021 in the Gila National Forest, New Mexico, with a Takahashi FSQ EDX4 telescope and ZWO ASI6200MM cooled 62 megapixel CMOS camera and Chroma filters on a Sky Watcher EQ6 auto-guided equatorial mount under control of a Raspberry Pi computer. The 18 one minute subframe images were calibrated, debayered, registered, integrated and post processed in PixInsight. About 3 hours before these images were taken my autoguider camera failed (bad cable?) so I took these images unguided but limited the exposure to 1 minute since this mount is not great. The image is cropped to about 40% of the original area.
I didn’t do any artificial enhancement to this image to “create art”. I think it is hard in a few minutes to improve on what Mother Nature did over billions of years.
As always please feel free to share any of my images.
CaliforniaNebula_NGC1499, captured 2015-09_20, camera: SonyA7s (centralDS modded and cooled) 52 subframes a 300sec IDAS-V4, scope: RASA 11" F/2.2, mount: EQ8, Guiding_scope, processed with PixInsight (registration), CCDware (stacking and deconvolution), Photoshop CS6 (final cosmetic corrections), Tenerife, 1180 m altitude.
IC 443 – The Jellyfish Nebula
IC 443 is a supernova remnant found in the direction of the constellation Gemini. It is thought that the supernova occurred sometime between 3,000 and 30,000 years ago. There is no known record of this supernova. The object is approximately 50 arc-minutes across and is thought to be about 5,000 light-years away.
Captured on 1-16-21 from the General Nathan Twinning Observatory (the dark sky site of the Albuquerque Astronomical Society) and 2-6-21 from my light-polluted Albuquerque backyard, using 7 nm band pass Sii, Halpha and Oiii filters on an ASI 1600mm camera, attached to an AT65 refractor mounted on a Losmandy G11 mount, this is at least my third attempt on this object. Previous attempts, made in RGB with OSC cameras have failed to yield satisfactory images. 36 x 300” subframes were captured in Sii, Halpha and Oii, for a total of 9 hours of data. All files were calibrated with darks, bias and flats, aligned and combined in PixInsight. I still found it somewhat difficult to obtain a finished image that I was satisfied with. One problem is the brightness of the stars Propus and μ Geminorum. In retrospect, I probably should have made separate images of much shorter duration and blended those into the final image. Nevertheless, this is by far the best image I’ve managed to make of this object.
Celestron C8 with Hyperstar using the new Optolong L-eXtreme F2 dual band filter. I wanted to test the glare reduction on bright stars. It works much better than the older version. ZWO ASI294MC Pro camera, stacked, preprocesses in Siril, processed in PI and some little tweaking in Photoshop
105 x 2minutes subframes
Gain 120
Astro-Tech 6" f/9 RC, ASI533MC Pro, iOptron HAE29 mount. Forty 90 second subframes. Dual narrow band filter. Calibrated with dark, flat, and bias frames. FOV about 32’ x 32’. The "head" of the seagull.
February 25, 2025, backyard, Tallahassee, Florida. Bortle 7 suburban sky. Seeing was poor. Guiding was fair (total error was around 1 arcsec on average) since I did a reasonably good polar alignment. Siril, PS, StarNet. I need to work on my stars, among other things.
I took this picture at the same time as my LRGB image closer in on 9 February. In this case taken through an 80mm triplet APO refractor but using an Atik Horizon colour CMOS camera with a deep sky filter. It was a test at high gain to see if Alnitak (just above the Flame nebula) would blow out in the image or be under control. This is a stack of 101 two-minute subframes. Darks and flats have been subtracted.
A deep sky filter may not be the solution long term, as it tends to clip the red end of the spectrum a little too much, as can be seen in this image. I have somewhat light-polluted skies to contend with but even if I didn't it would still be advisable to fit an appropriate filter. My next test of the Horizon will be with a specific UHC filter if all goes well.
Peter
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Photographed at Algonquin Provincial Park, Ontario, Canada
(285 km by road north of Toronto)
* Temperature 11 degrees C.
* Total exposure time: 10 minutes.
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Description:
Our home galaxy, the Milky Way, runs through the constellations Aquila (the Eagle) and Scutum (the Shield) in the northern hemisphere summer sky. Dense clouds of stars are obscured in places by winding lanes of dark foreground gas.
Numerous so-called "deep-sky objects" (dark nebulae, star clusters, bright diffuse nebulae) make wonderful targets for amateur astronomers with moderate telescopes who make the effort to travel out of our light-polluted cities to gaze at the wonder of the night sky.
For a version of this photo WITH LABELS, click on your screen to the RIGHT of the photo, or click here:
www.flickr.com/photos/97587627@N06/28046485616
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Technical information:
Sigma 50 mm f/1.4 DG HSM ART lens on Nikon D810a camera body, mounted on Astrophysics 1100GTO equatorial mount with a Kirk Enterprises ball head
Ten stacked frames; each frame:
50 mm focal length
ISO 3200; 1 minute exposure at f/4; unguided
(with LENR - long exposure noise reduction)
Subframes registered in RegiStar;
Stacked and processed in Photoshop CS6 (brightness, contrast, levels, colour balance)
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