[Theme] Night sky shots

[charlie]

Thanks Oivind (sorry,I don't know how to make the special norse characters).

(As for the Norse characteristics, you can simply copy&paste their names.   )

If you're on a Macbook you can hold down the key and a list of alternative letters you can use will pop up.

[armando_m]

Learning how to process this images seems to never stop
I thought Deepsky would produce the best results, but for andromeda I was not quite happy with the initial results
here is an attempt stacking the images in PS, with a median filter, then adjusting luminosity and colors in separate layers

I saw this method in videos by Ian Norman (Lonelyspeck) in you tube https://www.youtube.com/watch?v=Rltg47Q64W0


This is a stack of 12 frames , 30 seconds each

[basker]

Not a 3D camera? 

[armando_m]

Not a 3D camera? 

it is my android phone with the 70-300mm AFS zoom held with a rubber band, which also holds the aperture lever open

D800 with 80-200 f2.8 zoom mounted on the iOptron sky tracker
F/4 ISO 1600 30 secs

[basker]

Sure looks 3D to me. 

[BW]

Looks great Armando

[Anthony]

Superb, and thanks for posting a link to the processing video.

[Øivind Tøien]

Amando, great rendering of the dusty stuff in Andromeda! Amazing what you got out of this with so few exposures.

Now on to an old acquaintance of several members here from a very different occasion. It has been shining so bright in the south-western sky lately, it has even seemed brighter than the moon, so I had to have another meeting with it tonight although atmospheric conditions were not the best as can be seen from the variability in these frames:


NIKON 1 AW1, f/8 @ 420 mm, 1/500, ISO 160

NIKON 1 AW1, f/8 @ 420 mm, 1/640, ISO 160

NIKON 1 AW1, f/8 @ 420 mm, 1/640, ISO 160 (all 3 frames scaled up 2x)

Focusing was very easy with my Bahtinov mask on the lens, showing marked diffraction spikes. The EXIF confirms that this object is brighter than the moon. Only the last exposure did not show any blown channels before adjustment. The surprising thing is that the near maximum brightness as seen here does not occur when light is reflected from the full surface as with our moon, but at a glancing angle.

Perhaps someone here with an even longer lens and a more quiet sky can get a better view of Venus?

[armando_m]

Øivind

Wow, it is wonderful to see the planet being shaded by earth

A couple of nights ago I was out shooting orion again, while the images were taken, a friend and I were wondering what would it take to shoot venus as it was  the brightest object on the night sky, we figured a very long lens, and your images just confirm this , even 420mm on the Aw1 at 2x scale is not enough

I did try creating my own bathinov mask and did not get great results , I ended up focusing in live view

Thanks for sharing your images

[Akira]

Amazing celestial pageant, Øivind!

About 30 min later from this typing, NASA will make an important announcement about the planet outside the solar system.  I'm excited!

[Øivind Tøien]

Thanks Amando and Akira for the the kind comments.

Wow, it is wonderful to see the planet being shaded by earth

Actually earth cannot cast a shade on Venus if that is what you mean as it is always closer to the sun.    The shape is rather caused by some degree of backlighting, just as with crescent moon. On Venus that seems to be reflected more than when light is reflected back at a 90° angle, opposed what is the case with the moon. I was surprised reading about this recently.
 

A couple of nights ago I was out shooting orion again, while the images were taken, a friend and I were wondering what would it take to shoot venus as it was  the brightest object on the night sky, we figured a very long lens, and your images just confirm this , even 420mm on the Aw1 at 2x scale is not enough

Yes this is mostly done for own satisfaction. Planetary imaging is a specialty by itself. A more professional approach would be to use a high magnification refractor on a small sensor, and use video to capture as many frames as possible. Then one would use a program like Registax to automatically select the best frames and perform resolution stacking.

I did try creating my own bathinov mask and did not get great results , I ended up focusing in live view

I almost always use live view/image review at 100% view to focus with the Bahtinov mask. However except on the very brightest stars and planets, it is necessary to take an exposure (typically 10 sec) and evaluate the result. So it functions more like a focus confirmation tool most of the time than one used dynamically. What I can see is the stars becoming narrower in 100% view near correct focus when moving the focus ring. But sometimes it is just as easy without the mask attached to use the faintest visible stars in live view as focus targets, and then confirm focus with a Bahtinov mask exposure. If possible I also use it at the end of a series to see if focused changed. It might happen if I do not let the lens equilibrate long enough to outside temperatures.

My homemade Bahtinov mask:




Near perfect focus (heavy crop):

[Erik Lund]

I have never seen a  Bahtinov mask before, fascinatingly simple focus aid!

Seems to be spelled: Bahtinov

[Øivind Tøien]

Oops, sometimes ones fingers are thinking out of order. Corrected where needed, at least I got it right once. 

[Akira]

Never heard of Bahtinov mask.  Thanks for the education, Øivind!

[MFloyd]

Diffraction simulation with Bahtinov mask:

https://commons.wikimedia.org/wiki/File:Simulation_of_a_bahtinov_mask_diffraction_pattern_when_focusing.gif#/media/File:Simulation_of_a_bahtinov_mask_diffraction_pattern_when_focusing.gif