Author: JakubK

IC 4304 Rho Ophiuchi Nebula

Rho Ophiuchi is a triple star system (on the left side of the picture) in constellation Ophiuchus. The light from the stars is partially absorbed by the gas, which makes the blue reflection nebula visible. Smaller reflection nebula called IC 4603 is located on the right. The picture shows just small frame of significantly bigger nebula, called 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 significantly shorter focal length, like 130 – 200 mm.

The picture was taken under dark skies of Fuerteventura and it’s a stack of 73 pictures, 3 minutes each, which makes 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

M7 Ptolemy cluster

Messier 7, sometimes called Ptolemy cluster, is an open cluster located in between constellations Sagittarius and Scorpius. The cluster is visually located on the galactic plane of the Milky Way, therefore there are many stars in the background. The cluster is badly visible from Central Europe. Much better opportunities to observe or photograph this cluster have astronomers or astrophotographers in southern countries. My last attempt to capture it in Greece was constantly disturbed by the weather, therefore we I was again in South, specifically at Fuerteventura, I didn’t hesitate and recapture this beautiful cluster.

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
Exposure64x180s, 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 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, Lagoon nebula (right side) is an emission nebula – 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, second one with 630 mm and now I used 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 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

Samyang 24 mm f 1.4 review

I have been searching for a wide lens for my recently astro-modified, second hand Canon 6D. This means the lens should be suitable for a full-frame sensor 36 x 24 mm. The requirements on lenses are very tough for astrophotography because you photograph the stars – pinpoint sources of the light. The design/manufacturing flaws of the lenses are revealed on every astrophoto and optical aberrations spoil the good shot. Astrophotography of the Milky Way needs a lot of effort. Specifically, you have to travel to reach the dark sky and if you do so, you want to make nice pictures. In my opinion, the lens is the most important piece of equipment for astrophotography, because nowadays you can buy second hand Canon 6D, which is still very good and relatively inexpensive.

All the lenses are very sharp and aberration-free in the center of the picture, but the more you go off the axis, the aberrations start to pop up. There are many kinds of optical aberrations. Very nice article about the most common aberrations is on Lonely Speck.

Last year I purchased Samyang 14 mm f2.8, which is a great lens for the money, but the corners are not perfect and the stars are strongly deformed in every corner. I assumed that almost twice more expensive Samyang 24 mm f1.4 will perform much better and I also assumed that it’s easier to make a 24 mm lens compared to 14 mm. Moreover, f1.4 is a brilliant convincing argument. On the other hand, Samyang 24 mm doesn’t communicate with the camera, which means no EXIF of aperture and manual focus. This makes the lens a one-trick pony, suitable mainly for astrophotography and not that practical for regular photography.

Before I take this lens to the dark site, I decided to test it from my light-polluted home. The equipment: Canon 6Da, Baader Nanotracker, and of course, Samyang 24 mm f1.4. The main aim was to find the best aperture/sharpness ratio. Most of the lenses get sharper if slowed down. So I kept the exposure time 20 s, ISO 800, and was systematically changing the aperture from 1.4 to 2.8.

Here are the results of uncropped and uncorrected (no flats, no bias, no darks, and no noise reduction) pictures:

F1.4

F2.0

F2.4

F2.8

And the winner is…. obviously, the largest aperture (the smallest F number) collects the most of the light, but it vignettes strongly and honestly, the stars are ugly even in the center – this is totally unusable for serious astrophotography. The situation is not much improved by slowing the lens down to F2.0. At F2.4 the situation is significantly improved but at F2.8 the star roundness is acceptable almost everywhere, except the left corners.

Let’s have a look to the upper left corner – there the stars are the worst.

F1.4

F2.0

F2.4

F2.8

Conclusions

Samyang 24 mm F1.4 should be slowed down to at least to F2.4, to offer decent quality of the stars on a full-frame sensor. At F2.8 the quality is even slightly better, but at the top-left corners are the stars still elongated by astigmatic aberration. I expected better star quality, but in the end it’s not so dramatic, because the right side is not perfect, but acceptable. At least I know which side of the camera I should turn towards the ground if making a portrait picture of the Milky Way.


M5 Globular Cluster

Messier 5 is a globular cluster located in the constellation Serpens. I revisited this cluster after four years. Such a spectacular deep space object simply deserves more attention, than I was able to spend four years ago. At that time I used the same telescope, but now I have a different coma corrector and camera. Moreover, this time I dedicated significantly longer integration time, specifically I was collecting the photons 2.7 hours, which were traveling to us 24 500 years.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersNo
Exposure54x180s, Gain 95, bin 1x1,
Date2020-05-21

M98 M99 Galaxies

Messier 98 (left bottom) and 99 (right) are galaxies visually located in constellation Come Berenices. These galaxies interacted with each other long time ago, but it’s long time forgotten, because currently, the distance between them is 1.3 million light years.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure140x180s, Gain 94, bin 1x1,
Date2020-03-24

M44 Beehive Cluster

Messier 44, sometimes called Beehive cluster, is visually one of the biggest open cluster, which can be observed from northern hemisphere. Previous picture, taken 3 year ago, was done with focal length 1000 mm. Now I changed the strategy and used only 630 mm. I think this was a good idea and whole cluster is perfectly framed.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure76x180s, Gain 94, bin 1x1,
Date2020-03-46

M95 M96 M105 NGC 3384 and NGC 3389 Galaxies

Well, the weather was so bad very long time or the Moon was up and shining. I had almost no opportunity to capture something this year. Finally the sky cleared up and galactic season started (the spring). I was so excited that I wanted to capture as many deep space object at possible. Therefore I took the telescope with the shortest focal length I have (630 mm), pointed the telescope into the constellation Leo and captured 5 bright galaxies in one shot. M95 is the one at bottom left, M96 in middle and M105 the brightest at top right corner.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure76x180s, Gain 94, bin 1x1,
Date2020-03-18

M48 Open Cluster

Telescope is out after long time. My main targets for this night are some galaxies in constellation Leo, but I have to wait for these galaxies to cross the meridian (line splitting west and east). By browsing in planetarium software I found one object, which can fill the gap – it was the open cluster M48. Open cluster usually don’t need super dark skies, therefore I can capture them during the evening, when there is still strong light pollution. My previous picture was taken by much longer focal length, therefore the cluster covered nearly whole field of view. This time the background if filled by many stars, which are not members of this cluster.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure76x180s, Gain 94, bin 1x1,
Date2020-03-18

Chasing darkness in Greece – Karpathos

Like every summer, I packed the telescope, mount, camera and many accessories and flew to Greece. This time we went to Karpathos, the island not spoiled by massive tourism and light pollution. Long story short, the skies were amazing, but every single night, except one, was extremely windy. It was a torture – to see millions of stars and not be able to photograph them. There is no surprise that Karpathos is beloved by windsurfers and kite surfers. In the end I captured only the Iris Nebula and the Double Cluster. I talked to locals and they told me that the wind should stop at the end of September, so probably I picked the wrong time.

On the other hand I was able to do a wide angle astrophotography of the Milky Way. SQM reached 21.5, galactic core was so bright and I think the photos of the Milky Way are quite decent. This time I changed the setup and purchased Canon EOS 6D, which is one of the best cameras for this purpose. Moreover, there are many second hand 6Ds, because mirrorless mania arrived. 6D combined with Samyang 14 mm f2.8 offers excellent performance for this purpose.


Double Cluster NGC869 and NGC884

Two clusters visually close to each other can be located between constellations Perseus and Cassiopeia.  The clusters are relatively young (12 million years) and they are 2700 light-years far from Earth.

The picture was captured during my travel to Karpathos where I had only single wind free night.

I know, the composition should be turned by 90°. I just simply forgot to twist the camera.

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
Exposure28x180s, Gain 94, bin 1x1,
Date2019-09-03

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

M72 Globular Cluster in Aquarius

Messier 72 is a globular cluster, which can be located in constellation Aquarius. The cluster is approximately 55 light-years from us, which makes it one of the distant objects from Messier catalogue. M72 is very special deep space object for me, because it’s the last object of Messier catalogue captured by me. Now I am thinking, shall I continue and try to capture NGC catalogue? Or shall I move to southern hemisphere? I am definitely sure that some of the Messier’s objects need to be recaptured.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure60x180s, Gain 94, bin 1x1,
Date2019-08-09

M13 Great Globular Cluster in Hercules

In my opinion, Messier 13 is the most beautiful globular cluster in our galaxy. Last time when I photographed this cluster, I used focal reducer (don’t ask me why), therefore I decided to recapture it with focal length 1060 mm. Small galaxy in upper right corner is called NGC 6209.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure55x180s, Gain 94, bin 1x1,
Date2019-06-07

M10 Globular Cluster

Messier 10 is a globular cluster located in constellation Ophiuchus. This cluster belongs to one of the closest to the Earth – the distance is “only” 14 300 light-years. It has visually many globular neighbors: M12 northwest, M14 east and M107 southwest.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure38x180s, Gain 94, bin 1x1,
Date2019-06-02

M12 Globular Cluster

Messier 12 is a globular cluster located in constellation Ophiuchus. The cluster is 15,700 light-years away from Earth and contains approximately 200,000 stars. There are another two globular clusters in the vicinity: M10 south-east and M14 east.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure32x180s, Gain 94, bin 1x1,
Date2019-06-01

M40 Double Star

Messier 40 is a double star located in constellation Ursa Major (in the middle of the picture). Charles Messier was searching for the nebula in this part of the sky, which was observed by Johannes Hevelius. He was unable to locate any nebulous object, but he found this double star and catalogued them under the number 40. Double star should be a system of two stars, which are bonded by the gravity, but the latest measurements demonstrated that these two stars are close to each other only visually and they are completely unrelated.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure40x120s, Gain 94, bin 1x1,
Date2019-06-01

M101 Pinwheel Galaxy

Messier 101 is a beautiful spiral galaxy, which can be located in constellation Ursa Major. If I look back to my older picture, I must smile, how I overdone the saturation and whole post-processing. Such beautiful galaxy deserves to be re-captured and processed again:

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure31x300s, Gain 94, bin 1x1,
Date2019-06-01

M102 Spindle Galaxy

Galactic season continues. After capturing M64 galaxy, I pointed my telescope to another one. Specifically to Messier 102 called Spindle Galaxy, which is a lenticular galaxy in constellation Draco. Afterwards I went to sleep and the telescope was collecting the photons coming from there. The light had to travel very long distance, because this galaxy is approximately 40 million light-years from Earth.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure55x180s, Gain 94, bin 1x1,
Date2019-05-24

M64 Black Eye Galaxy

Messier 64 is a galaxy, which can be located in constellation Coma Berenices. The name “Black Eye” or sometimes “Evil Eye” got from the central dark cloud, which blocks partially the light coming from there. This galaxy is relatively close to us – only 17 million light-year, which is significantly less compared to visually neighboring galaxies in constellation Virgo.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure24x180s, Gain 94, bin 1x1,
Date2019-05-23