Category: Dark Nebula

Rho Ophiuchi cloud complex

The brightest orange star is the Antares, which represents the head of the constellation Scorpius. This star has surrounded all kinds of nebulae – dark, reflection, emission. Basically, nearly all the colors of the universe can be seen here.

TelescopeWilliam Optics RedCat 51/250 f4.9
Aperture51 mm
Focal length250 mm
MountiOptron Skyguider Pro
AutoguidingZWO 178MM, QHY Mini Guide Scope 30/130 mm
CameraCanon EOS 6Da
Filtersnone
Exposure60x120s, ISO 1600
Date2022-05-29

B33 HORSEHEAD NEBULA

Horsehead nebula is IMHO the most beautiful deep space object. It is located in the constellation Orion. Everybody knows this constellation because it can be easily identified by three aligned stars (Alnitak, Alnilam, and Mintaka), which forms the belt of the Orion.

The nebula is very dim. Therefore, visual observation is nearly impossible, unless you have a telescope, having at least 1 meter in diameter. To photograph it, one needs a very long exposure time. I used 5 minutes per image and I took 36 of them. The nebula complex is visually very large, so the optimal focal length should be shorter than 750 mm. I used a Newtonian telescope with a focal length of 1000 mm but reduced to 750 mm by the Nexus coma corrector. It turns the Newtonian into a light-collecting bucket, but the quality suffers from that. The stars in the corners are everything, but round. Moreover, I used dual-band filter Optolong L-eXtreme, which increased the contrast of the nebula, but also made the asymmetric halo around the bright stars. I played a bit with the white balance and pushed the colors into the orange tint, to reach the warmer feeling in cold February.

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length750 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorNexus coma corrector
FiltersOptolong l-eXtreme
Exposure36x300s, Gain 95, bin 1x1,
Date2022-02-09

Cygnus

I went to Crete without a detailed plan on which deep space objects to capture. The primary target was Rho Ophiuchi, which I captured really well. Then I started to think about the next objects. Obviously, if you are in a dark place, you can point your camera nearly anywhere. However, there are some regions full of stars and deep space objects. For example constellation Cygnus, which is sometimes called the Northern Cross. It is located visually on the plane of the Milky Way galactic disk, therefore there are many deep space objects.

Let’s have a look at a wide-field picture captured by a 24 mm lens attached to Canon EOS 6Da:

Let’s zoom a bit by changing the lens to a 50 mm focal length. Here the constellation is perfectly centered:

Let’s zoom further to the central star Sadr by change of the lens to 180 mm focal length:

Let’s keep the focal length 180 mm and let’s have a look at the left star Deneb and very famous North America nebula:

Again, let’s keep the focal length 180 mm and change to perspective to the bottom (eastern) star Aljanah, where the beautiful supernova remnant the Veil nebula is located:

In total, the camera collected 15.5 hours of light and I am happy with the result.


IC1396 Elephant’s Trunk nebula

Elephant’s Trunk nebula is an emission nebula located in constellation Cepheus. I tried to capture this magnificent nebula in 2017 and in 2018, but it never fit in the field of view of my camera-telescope assembly. This time I used a focal length of only 180 mm, combined with a large full-frame sensor. Well, and finally it fits. Moreover, even the B174 dark nebula at the bottom left corner found the spot on the sensor. The picture was taken under a very dark Cretan sky.

Technical details:

LensAskar FMA180 F4.5
CameraCanon EOS 6Da
MountiOptron Skyguider Pro
Exposure159x120s, ISO 1600
Date2021-07-08

IC 4304 Rho Ophiuchi Nebula

Rho Ophiuchi is a triple star system (on the left side of the picture) in the constellation Ophiuchus. The light from the stars is partially absorbed by the gas, which makes the blue reflection nebula visible. A smaller reflection nebula called IC 4603 is located on the right. The picture shows just a small frame of the significantly bigger nebula, called the Rho Ophiuchi complex, which combines star Antares, globular cluster M4, and many more reflection, emission, and dark nebulae. In order to capture the whole complex, one has to use a significantly shorter focal length, like 130 – 200 mm.

The picture was taken under the dark skies of Fuerteventura and it’s a stack of 73 pictures, 3 minutes each, which makes the total integration time 219 minutes.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length570 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-0°C
CorrectorTS MaxField
FiltersNo
Exposure73x180s, Gain 94, bin 1x1,
Date2020-07-21

M8 Lagoon Nebula, M20 Trifid Nebula

These two magnificent nebulae are located visually close to each other in the constellation Sagittarius. This means we are looking in direction of the galactic core of the Milky Way. Trifid Nebula (up left) is a combination of a reflection nebula (blue part), a dark nebula (brown clouds), an emission nebula (red part), and a star cluster. On the other hand, the Lagoon nebula (right side) is an emission nebula – a giant cloud of ionized HII gas. Due to very low southern declination, it’s very difficult to photograph these deep space objects from my home place in Central Europe. Therefore every time I travel south, I take the opportunity and recapture these nebulae. My first attempt of M20 was done with focal length 917 mm, the second one with 630 mm and now I used a gentle focal reducer. Focal length 570 mm allowed me to fit both nebulae into the field of view of APS-C sensor size. The picture is an integration of 213 minutes, taken under the dark skies of Fuerteventura.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length570 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-0°C
CorrectorTS MaxField
FiltersNo
Exposure71x180s, Gain 94, bin 1x1,
Date2020-07-18

NGC7023 Iris nebula

Iris nebula, known as NGC 7023, is a reflection/dark nebula located in constellation Cepheus. It’s 1300 light years far from the Solar system and it has 6 light years in diameter. In the middle of the nebula rules so called baby star, which is only few thousand years old. The star was created partially from the gas which is now illuminated.

The picture was taken under dark skies of Greek island Karpathos during my 2019 expedition. Unfortunately, the weather was very bad. There wasn’t a single cloud on the sky, but it was extremely windy, therefore I got only one single steady night and this night I wanted to capture also other deep space objects. Therefore the picture is a stack of only 37 pictures, each 2 minutes long.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-5°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure37x120s, Gain 94, bin 1x1,
Date2019-09-03

IC5146 Cocoon Nebula

IC5146, sometimes called Cocoon Nebula, is an emissive nebula located in constellation Cygnus. Central star in the nebula is responsible for the excitation of the surrounding hydrogen gas. On the picture is also captured dark nebula Barnard 168, which creates the strip and it looks like the Cocoon Nebula has a tail.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length660 mm
MountiOptron CEM25P
AutoguidingQHYCCD miniGuideScope 130 mm f/4.3, ZWO 174 MM
CameraZWO 071 Pro @-10C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure43x300s, Gain 134, bin 1x1,
Date2018-09-13


IC 1318 Butterfly Nebula, Barnard 347

IC 1318 is an emission nebula, sometimes called Sadr region, located in constellation Cygnus, surrounding bright star Sadr. The star Sadr didn’t fit into the field view of my telescope/camera, but left the trace in form of diffraction spike at the top of the picture. The nebula contains many dark nebulae and the biggest in the middle of the picture is called Barnard 347.

The picture is another demonstration of dark skies of Milos and it is an integration of 77 pictures, each 3 minutes exposure, which means nearly 4 hours of integration time.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length660 mm
MountiOptron CEM25P
AutoguidingQHYCCD miniGuideScope 130 mm f/4.3, ZWO 174 MM
CameraZWO 071 Pro @-10C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure77x180s, Gain 134, bin 1x1,
Date2018-09-05