Galaxies

Welcome to the Galaxies image page. Here you’ll access some of my pictures.


Object: NGC4565


NGC4565 v2Description
: This galaxy lies in Coma Berenices, and it’s about 47 million light years away. This beauty is edge-on, and it clearly shows the dust bands in its plane. The smaller companion is NGC4562.

Technical data: 2012/06/15. Meade LX-200R 8″ at F7.7, QSI583WSG, guided with the DSI Pro. Subs are: three 5-minute thru L filter, binned 2X2, and three 10-minute subs thru R, G and B,
binned also 2X2. Adquired with Maxim/DL, registered with DeepSkyStacker, and processed with PixInsight. Flats where taken and applied.


 Object: NGC3190 galaxy group


NGC3193 L40m RGB30m v3Description
: The picture shows the galaxy group knonw as NGC3190, some 60 million light years away, in Leo.NGC3193 is the difuse elliptical near the center. NGC3190 is the beautiful spiral, near edge-on, showing the clear dust lane in its plane. NGC3187, to its right, is another spiral, with distorted arms due to the interaction with NGC3190. NGC3185 appears in the top right side of the picture, but it is not related with the group. Also, at least two other faint galaxies can be seen.

Technical data: 2011/04/09. Meade LX-200 8″ at F7.7, QSI-583WSG with Astrodon RGB and Luminance filters, guiding with the DSI Pro. Subs are: four 10-minute through Luminance, and three 10-minute subs through R, G and B filters (130 minutes total). Adquired with Maxim/DL, registered with DeepSkyStacker, and processed with PixInsight. I haven’t been able to completely remove the small gradient at the top of the image without affecting the faint galaxy there. Also, a satellite track shows at the left.


 Object: NGC7331 galaxy group

NGC7331Description: This beautiful galaxy, NGC7331, lies in the constellation of Pegasus, and it’s surrounded by several smaller galaxies. It is about 45 million light years away.

In the processing, I used deconvolution, as I usually do with big galaxies. But before that I protected the background and the stars with a Luminance and a custom star masks. The latter is key to a good deconvolution process, so some time must be devoted to build it as perfect as possible.

slide-NGC7331

 

 

 

 

 

 


 Object: NGC4038 & NGC4039 (Antennae Galaxies)

Antennae GalaxiesDescription: These two remarkable galaxies, about 45 milion light years away, are undergoing a collision, that eventually will result in a complete merge of them. This merge may have begun about 600 million years ago.

It seems that this interaction is fueling a busy star creation activity in both galaxies, and the picture shows many red and pink active areas. One of the most famous features are the antenas, after this couple is called. These long tails of stars Antennae Galaxies invertedand dust can be better seen in the inverted version of the image. It happens that the interaction creates these tails. Will the collision between our Milky Way and Andromeda look the same in the far future?

Technical data and processing: My main challenge while processing was to be sure the long tails were shown. They are pretty dim, amb whatever existing light gradient can greately spoil this feature.

I used deconvolution for the galaxy cores, and noise reduction procedures to smoothen the background.

Slide Antennae

 

 

 

 

 

 


 Object: M63 (The Sunflower Galaxy)

m63Description: This beautiful galaxy, about 35 milion light years away, shows a lot of fine detail if carefully imaged and processed.

The details of its delicate structure can be better seen in the inversed version.

For this image, I tried a new guiding cycle. I had usually used a 3-secong cycle, which worked well. In fact, I had observed that without a very good polar alignment, using a lower cycle could lead to the guiding system chasing the drift in declination as a fool, spoiling the overall guiding session. But as I have changed my daily routine, introducing a Pempro polar alignment process every night, the Y-axis guiding (declination) had improved so much that, then, my problems with RA guiding began to show up. So, I decided it was time to lower the guiding cycle to 1 second. Fortunately, I could find a guiding star bright enough to allow for this low exposure.

m63 zoomm63 zoom inversed

With this change in the cycle duration, I learnt that I needed to also lower the aggresiveness in Maxim DL guiding both for X and Y. Overall, this first attempt with the new configuration was a success, as you can see in this zoom:

guiding improved

Technical data and processing: Processing this galaxy was about trying to get the most I could from the details and the structure.

I used deconvolution, as always, for the galaxy core and spiral, and noise reduction procedures to smoothen the background. I also enhanced the color saturation of the galaxy.

Technical data sheet

 

 

 

 

 

 

 


 Object: NGC4889 and surrounding galaxies

Coma BerenicesDescription: OK, so this is my personal “Hubble deep sky field”. My goal was to catch a huge group of galaxies in Coma Berenices, and try to identify as many of them as I could.

These galaxies are some hundred milions light years away (NGC4889 is 250 ly).

It’s amazing. In such a narrow field (less than half a square Coma Berenices comentadadegree), there’re a lot of galaxies. Of them, I’ve been able, so far, to name 124. But, as I did so, I was skiping weak points which, probably, are also galaxies, maybe too faint to deserve a name. I guess that there may be some 200 to 300 galaxies in this image.

Technical data and processing: the main difficulty was gradient removal. Although I used flats, and imaged under a moonless sky, I got a nasty gradient which I cannot identify. It appeared in almost all of my frames, so I call off clouds. I also inspected my flats, but they’re good. The thing is that when you work with weak objects (like these) gradients show up very easily. Due to this I’m sure I’ve lost some of the faintest detail of my subs, but anyway I’m quite OK with the result.

Slide NGC4889

 

 

 

 

 

 


Object: M51 (with a supernova!)

M51 nou processat abril 2013Description: M51 is a grand spiral, lying about 30 million light years away. What seems to be a close interaction with a small galaxy, NGC5195, is only an optical illusion, as the small companion is perhaps half million light years appart from the Whirlpool. Nevertheless it is pretty provable that the two galaxies have interacted in the past, and that interaction triggered star formation in M51, process which continues today at a rithm of 4 new stars per year. This is the same birth rate as in our galaxy, … but M51 has 10 times less mass. Look foM51 with supernova processed nova amb nomr the 2011 supernova!

Technical data and Processing: this galaxy is a joy to image. Consider this: my picture gathers “only” 4.800 seconds of light, and has 3 subs in L, 2 in R and B, and only 1 sub in G due to technical problems. I took no flat frames. Finally, the Moon shone brightly that night. As a result, my processing had to deal with strong light gradients (you know that getting rid of gradients is an awful way to wash out delicate and faint details of your target), was full of noise in the background, and was completely umbalanced in color.

Slide M51Despite all of this, the signal of this beauty is strong enough, and the result is more than acceptable.


 Object: M101


M101 v2Description
: In Ursa Major, this galaxy is face-on. It is very actively creating new stars. It lies 25 million light years away.

Technical data and processing: For this picture, I used the LRGB filter combination, but adding also H-alfa signal. I did so to strengthen the most active parts of the galaxy, which look pink and red in the image.

This is one remarkable example of how a appropiate processing technique pays off. At first, when I imaged it, I used my (poor) processing skills at that time, and generated an image which, for me, was wonderful: M101 is really a challenge, as it has a relative low contrast.  Then, I revisited it after a year, and used wavelet techniques while processing. I got a lot of “new information”: yes, the signal was there, but hidden and waiting for me to uncover it. But the great improvement came after two years, when I tried deconvolution with it. Awesome result!

M101 compared

You can read how deconvolution works with M101 in my Articles section.

Slide M101

 

 

 

 

 

 


 Object: M33

M33 new processingDescription: M33 is one of the main galaxies in our local group. In fact it’s the biggest after M31 and our Milky Way. It is about 2.8 million light years away. The image is a mosaic of two parts.

Technical data and processing: I tried this object with some respect. My previous attemps with the Meade DSI Pro as my main CCD (before having the QSI) were discouraging. M33 is a huge object, and you need quite a wide FOV to get the whole galaxy. So, I decided to go for it using a 2-part mosaic. I chose a moonless night for this.

I had problems processing the mosaic, as the two parts didn’t match their dynamic ranges. Altough I used the mosaic techniques learnt with my processing of the Veil Nebula (you can read the details in the Articles section) I wasn’t able to reach a good match between the two parts. I haven’t a sure explanation for this issue, but it might be related to some kind of gradient appearing in some of the subs. In a first processing, this issue forced me to stretch the mosaic too much, losing some fine details and getting a final image which looks a bit too darker.

But I came back to this processing some months afterwards, and tried a smoother treatment. I also tried to resolve the galaxy core, as in my first attempt it was burned. A comparison between both processing approaches can be seen in the tecnical data sheet.

M33 invertit

Being M33 so close to us, one can capture a lot of detail. But, on the other side, its spiral structure can be difficult to see with so much detail. An inverted image helps with this, and the spiral arms appear clearer.

 

 

Slide M33

 

 

 

 

 

 

After some years, and with the new equipment (a 80mm APO refractor) I said goodbye to the mosaic need for this baby:

M33 signedTechnical data and processing: This huge target represents no problem to my 80mm refractor paired with the QSI. Processing used strong star masks and deconvolution treatment, only to the L component, before combining with the RGB composite.

This is the tech slide for it:

M33 slide

 

 

 

 

 

 


 Object: NGC4631


whale galaxyDescription
: This galaxy is called the Whale Galaxy, and you can see it swimming with her calf. It’s a distorted spiral, seen edge-on, about 30 million light years from us. NGC4631 shows much detail in its galactic plane, and many red and pink knots signal places where new stars are born. Dwarf elliptical galaxy NGC4627 is the “calf”.

Technical data and processing: A clear and transparent night without Moon, a PemPro polar alignment before the imaging session which allowed for a quite good guiding, and 8.200 seconds of gathered light were the key elements to get this detailed image of the Whale and its calf.

Applying flat frames correction is critical with this kind of objects. While nebulae and other extense objects can, more or less, survive without flats, galaxies, which are weaker and much smaller need the flats treatment to be able to get the fine details of their structures.

I incorporated, in my imaging routine, a PemPro polar alignment as a first step in the evening. Although it’s time consuming (I need roughly betwen 30-45 minutes for this), I’ve discovered that it really pays off, as one can have a very smooth guiding session afterwards. As you can see in the Technical data sheet, the guiding for this session was remarkably good. The error peaks appeared in the X axis, while the Y axis (which is the “crazy” one) remained stable. In future sessions, I’ll try to reduce the X errors lowering the exposure of the guider (I’m using 3 seconds), so that it can take care of the bumpy movements of the RA drive of my LX200.

whale galaxy cropped

I used deconvolution while processing. As I learnt with M101, galaxies can benefit a lot from this processing technique, as long as there is enough signal in the image. In this case, I was able to gather enough light, and a lot of details in the galaxy plane were uncovered thanks to deconvolution (please read my article about deconvolution for more information about this technique).

Slide Whale

 

 

 

 

 

 


Object: M65 and M66

M65 M66Description: These pair of galaxies fly in the constellation of Leo. They are beautiful examples of spirals. We see M65 (top right) a bit edged, and M66 almost face on.

Technical data and processing: I began the imaging session as soon in the evening as I could, to avoid the Moon. To shorten the whole thing, I used 3X3 binning with the R, G and B subs, with exposures of 200 seconds. Although guiding was not perfect, I am quite satisfied with the result, as a lot of features in both galaxies can be seen.

M66 invertit M66M65 invertit M65

In these views, some of the structures of both galaxies can be seen, thanks to the inverted image. See the bar of M66, which is shown very clearly.

Slide M65 and M66

 

 

 

 

 

 

And also with a wider FOV, yielded by my new setup (TS APO 80mm coupled with the QSI583):

Leo Trio landscape signed

 

 

 

 

This is the technical sheet:

Leo trio slide

 

 

 

 

 

 


Object: M81


M81 M82 cropped signedDescription
: M81, also known as the Bode’s galaxy, is a beautiful spiral, some 12 millions light years from here. It harbours a giant black hole in its center, and in its arms some star forming regions can be identified. In my photographic field it appears with M82 (please read this galaxy description in the following section)

Technical data and processing: This picture was obtained with my new setup, that yiels about 2.5X3 degrees of field. Processing used strong star masks and deconvolution treatment.

This is the non-cropped, original image:

M81 M82 signed

 

 

 

 

 

 

And this is the technical data sheet:

slide M81

 

 

 

 

 

 


Object: M82

M82Description: M82 is a all-time favorite. This galaxy is awesome as it’s strongly emitting jets, probably due to the acretion of matter around a supermasive black hole. Sometimes it’s called the “cigar galaxy”. This object lives at some 12 million light years from here.

Technical data and processing: First thing to point out for this image is that it contains a supernova! Its SN2014J, a type Ia supernova which happened to be on the show those dates. It can be seen as a very bright point inside the galaxy (to the right of the central part).

We had a bright Moon, and gradients have been an issue while processing this beast. We used R,G and B Johnson filters, together with a H-alpha one to stress the emission. The exposures varied with the filters. As we were using a big telescope (the 150-cm telescope at Obervatorio de Sierra Nevada) we didn’t want to saturate the brightest parts. You can read the detail in the technical sheet below. Processing consisted in gradient cure, deconvolution for the central part of the galaxy, and histogram and curves adjustments.

slide-M82

 

 

 

 

 

 


Object: M106

M106Description: M106 is a bright galaxy at Canes Venatici. In fact, it’s considered a big spiral, the size of M31 (so, bigger than out Milky Way). It’s about 25 million light years away, and it emits strongly in X rays, an indication of an intense activity propably due to the work of its supermasive black hole at the center.

Technical data and processing: Imaging this object needs a lot of light, to uncover the subtle details of the external parts of the spiral structure, which appears weak compared with the much brighter core. In my case, some clouds spoiled the session, so I could only gather 3 subs for each filter. It was a challenge to try to get the light out from the spiral while processing, and I did my best (but I wish I could have had some more photons!). The Moonlight indiced some gradient, which should be removed. Deconvolution, applied very carefully to the central part of the galaxy, and using a local star mask, worked some remarkable improvements on the details.

slide-m106

 

 

 

 

 


Object: M31, Andromeda galaxy

 

Andromeda signedDescription: The Andromeda galaxy is the larger member of our local galaxy group. It’s a bit larger that our own galaxy, the Milky Way. Both objects are in a collision path, which will take place some 3.5 billion years from now. M31 is 2.4 million lightyears from out home.

Technical data and processing: This is a huge target, and it needs wide field astrophotography to be imaged. My picture was obtained with my new setup, that yiels about 2.5X3 degrees of field. Processing used strong star masks and deconvolution treatment, only to the L component, before combining with the RGB composite.

Captura