August 2014: stunning Milky Way from Tanzania

Taking advantage of my summer trip to northern Tanzania, I took some pictures of that wonderful night sky. Far from any urban presence, and sorounded by bright eyes illuminated with my flaslight, I pointed my Canon 70D camera up to the sky, using a sturdy tripod, and a cable shutter to avoid vibrations. I tested some configurations, but in all of them I used a 18mm, f3.5 lens, and ISO from 200 to 400. Exposure times from 15 to 20 seconds. And image quality set to RAW. I used dark frames for processing, and I stacked up to 8 subs for image.

Here are some of the results. I have marked in them interesting objects:

sky03 iso400 15s 8frames

 

sky03 iso400 15s 8frames identification

sky05 iso400 15s 5frames

sky05 iso400 15s 5frames identification

    Go to this object description and this image technical detail.

July 2014: M106

Image

After some time without imaging (I’m very busy with my astrophysics master program), I came back to my CCD with this galaxy. The imaging session was abruptly terminated when some high clouds had my star guide lost. I could only cath 3 subs for each filter. Althpugh I used 500-second exposures for my subs, this was not enough to clearly uncover the weak and subtle external parts of this beautiful spiral. I trued to do my best while processing, to extract light from this area. As always, deconvolution worked miracles on the central part of the galaxy.

M106

 

   Go to this object description and this image technical detail.

April 2014… with the 1,5m telescope at OSN!

Yes! My colleagues (Sara, Javi, Gunther, Erik) and I had the chance to remotely use, for three nights in a row, the telescopes of the Observatorio de Sierra Nevada. This observatory, which is almost 3.000m high up in the mountains, has two big, professional telescopes (90 and 150 cms). It is  not usual for this kind of observatories to allow use to non-professionals, but this was a remarkable exception thanks to the Valencian International University in which we are currently developing a astronomy and astrophysics master program. We were brightly assisted by the staff at OSN.

We used our nights for some science projects, and had time to image some wonders of the sky. Working at bin2x2, we were at a theoretical 0,46 arcsec/pixel  scale, limited in fact by the seeing. With a FOV of only 8 arcmin, the 1024X1024 pixels of the VersArray CCD delivered an extraordinary amount of information, so we aimed at tiny but interesting objects.

M97, the Owl Nebula (narrowband), and M82 with its supernova SN2014J were two of these objects:

M82

   Go to this object description and this image technical detail.

 

M97

   Go to this object description and this image technical detail.

December 2013: the hidden secrets of M42

If there’s a visited target in the sky, that’s for sure M42.

The bright Orion Nebula is an easy target for any type of equipment and expertise. But this object hides inside its core some secrets which are a challenge to uncover. How can this be?

M42

The intense core of the nebula is so bright that images are overexposed. To avoid this, one must take short exposures subs. But at the same time, short exposures cannot get the detail out of the fainter part of the object.

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December 2013: a comet that defied the Sun… and lost

Comet ISON was an awaited visitor. Although nobody could be sure of its fate when it got close to the Sun, many thought that it could become “the comet of the century” if it survived. As you know, it didn’t.

Before its demise, I took some pictures of it. It was about two weeks before perihelium.

OK, I don’t know much about comet photography and processing. I tried short shots (30 seconds) , to be sure the movement of the coment didin’t show up in the pictures.

I created two pictures: one in color, adding only two frames in each channel (RGB). And one in B&W, stacking several L frames (and getting rid of the background stars while stacking).

ison v6 ison naked

November 2013… and the Helix

This is the Helix Nebula. A remarkable planetary nebula, the death of a solar-like star, which remains as a white dwarf in the middle of the nebula.

The Helix is one of the biggest planetaries, because it’s pretty close, at 680 light years away. Unfortunately, this object is pretty low over the horizon from my latitude, and this is not good as more atmosphere to cross means noisier images.

I couldn’t get more subs to improve the signat to noise ratio, as the Helix was setting very quickly. Despite of this, I’ve tried to get rid of much the noise while processing. The intense blue color of the middle is due to excited Oxigen atoms.

helix

   Go to this object description and this image technical detail.

October 2013: NGC7331 galaxy group

In a moonless, dark night, I imaged this beautiful galaxy, surrounded by other minor galaxies.

As usual, I applied deconvolution in postprocessing, using luminance and custom star masks to do so. I boosted the blue color of NGC7331.

NGC7331

 

  Go to this object description and this image technical detail.

Guiding was quite good, and I run a Pempro alignment process before imaging, to allow for a smooth guiding. In fact, I was able to turn off corrections along the Y axis (declination) during some time while imaging (close to the meridian).

Improving the guiding during August 2013… and results

Yes, guiding is one of the big challenges of astrophotography, … and more for some of us who cannot afford the great, state-of-the-art, but very expensive, mounts out there.

It’s been some time since I introduced an alignment run every night, as part of my routine. I do so with Pempro, a great utility. Although this step takes valuable time off of my session, it really pays off, as guiding is smoother. As it’s commonly said, the best guiding is the one that isn’t needed at all.

The result of my improvements are two images. The first is M27, the Dumbbell nebula in Vulpecula:

M27 detail

  Go to this object description and this image technical detail.

And the second is part of the Sharpless 2-132 complex in Cepheus: Continue reading

M8: a mosaic for the Lagoon

M8 is quite an easy target for astrophotographers. This nebula, in the heart of the Milky Way is very bright and full of details. But, for some configurations (as mine), its large surface turns things a bit tricky if you want get all of the nebula in the FOV.

I tried a little, two-piece mosaic with it. And it worked quite well!

M8

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