[Theme] Night sky shots

[Jakov Minić]

Bjørn, you dug it out! You put a smile on my face
This was my first star trail experience in my life!
Erik's 8mm fish-eye that inspired me so much and got me hooked to a lot of things...

[Peter Connan]

Thanks Armando

Bjorn that is excellent!

[armando_m]

What a difference it makes when the shot is taken in a truly dark location

5 vertical frames pano, moon rise 
20mm, 20 sec iso 1600 f1.8

[Akira]

This is breathtaking, Armando...

[armando_m]

This is breathtaking, Armando...

Thanks Akira

It took some effort to get up really early three days in a row, this sequence was captured on the third try
1. travel
2. to much moon
3. success!

The image has minimal processing, converted to TIF and stitched, no added contrast, light curves, saturation, dehaze or any other post processing trickery

[BW]

I like the picture but I really feel this deserves "post processing trickery". At least a little bit.

[armando_m]

I like the picture but I really feel this deserves "post processing trickery". At least a little bit.

Yes, agree completely, I was just thrilled with the quality of the SOOC conversions
I'll like to make the sky darker , without it looking over done, always a difficult balance for me

[BW]

If you use PS you can always "overcook" the different layers and then reduce the opacity to fit your taste. The milkyway deserves some contrast and clarity to really stand out. Since you have very little light pollution you wont get those ugly color cast that would otherwise occur. The foreground also need to be a little darker, IMO

[John Geerts]

Impressive shot, Armando. Gives a beautiful spacial effect.

[Thomas G]

Atmosphere over Denmark. D700, 17-35/2.8 @ 17 mm, f/2.8, t=20,0 sec, ISO 1600

[Jakov Minić]

Spectacular Armando and Thomas!

[armando_m]

Very nice Thomas!

Here is a rework of the image from reply #17

[Akira]

Armando, the second version looks nice, but I think the first one looks more realistic to me.

By the way, you say you stitched the image.  I wonder if the stars are also properly aligned?

[Øivind Tøien]

Lots of nice images in this thread!

I recently got busy with a new toy for night sky photography.      (If it is inappropriate with equipment in this thread, please move this post to where it best fits, the first image results in the next posts).

The device is a tracker that compensates for earth rotation so that longer shots/longer focal lengths can be captured without star trails. Using it goes as follows:
1. I mount the iOptron Skytracker directly to the tripod in the zero position of the altitude adjustment with the front facing towards the far tripod leg, I place the tripod with that leg pointing north, fine adjust direction with the rotating base using a hand compass (taking deviation of magnetic north into consideration, +18° in Fairbanks!) and level it (with a the level I added by adjusting and taping it to the top).
2. The altitude adjustment it set proper to the latitude.
3. Now the polar scope is mounted, the motor/LED for the polar scope turned on, and the polar star will usually be visible or just out of the frame. Proper adjustment is made placing the polar star in the reticle at a position found with a polar alignment application.
3. Tripod head/camera is mounted to the rotating platform, pointed at  subject of interest in the sky and carefully focused (I prefer to use the tiniest stars visible for this).
4. Polar star adjustment is checked/adjusted again to compensate for any flex in the system.
5. Take test exposure to check framing, exposure and tracking, possibly repeat the adjustments.
6. Start intervallometer to take a long series of exposures with live view and 3 second delay activated. Go away from tripod and take a cup of tea or capture images of  the setup during the long wait, trying to stay warm...   




Because of neck strain I very soon added a DR-4 right angle finder from ebay at $25 shipped and adapted it to the polar scope, integrating part of a DK-22 to provide the proper threads in the adapter.




Compared to the alternatives, the Skytracker is very economical at $300, which includes the polar scope packed in a neat little bag, and can be used without adding a geared head for mounting and polar adjustment (typically >$250 for the Manfrotto junior, and at an additional weight of > 1 kg) as the alt/azimuth adjustment is integrated in the device. I also like that the polar scope can be used without removing camera/tripod head and while everything is in the final position, which is crucial when using a lighter tripod.

An extremely useful planning tool is the open source 3D planetarium application Stellarium http://www.stellarium.org/. Any position and time on earth can be dialed in, exact sunset/rise, moon rise/moon set, and search for any sky object, and lots of switches for foreground grids, atmopshere etc. etc. and a staggering large database of stars. Nebulas are shown as one would photograph them, and one can specify the angle of the zoomed view to simulate the shot almost exactly. So it is a very nice preparation tool or just to do some armchair exploration.


 

[Øivind Tøien]

First tries with the Skytracker - Orion Nebula and the Pleiades.

Tracking devices like the Skytracker is designed for wide area imaging (typically from very wide up to 100mm, stretching it to 200mm). With 135mm 5 minute exposures seemed feasible. I quickly found that I wanted to test the limits, mounting the lightweight 300mm f/4 E PF and my D7100. This works well up to a minute, and in some cases I have stretched it to 2-3 minutes (then throwing away the worst frames where periodic tracking error, PE, kicks in).  This has worked so well that most of the imaging I have done with the Skytracker so far has been with the 300mm. It has been limited by pretty strong light pollution in a red zone, and imaging closer to the horizon can be a bit shaky due to unstable air and inversion layers. The light pollution was subtracted partially in Deep Sky Stacker and finally in CNX2 in a levels step. White balance was not used to compensate.

The Pleiades:
Pleiades, M 45, Stack of 10 images at 50 sec, 300mm at f/4.5, ISO 1600. Crop to ca. 1/2 of the frame.





The fist captures of the Orion nebula, M42 I only got in 4 frames before trees got in the way because of the low position on the horizon of the Orion constellation.
45 sec, 300mm at f/4.5 ISO 1250, crop to less than half the frame.




Next time I found a location with a free view, but more light pollution and disturbance in the air
causing poorer resolution and likely some distortion of star shapes.  Stack of 44 frames,  300mm at 60 sec, f/4, ISO 640.




The whole frame with a slightly different edit/stacking parameters.




In the upper left of the frame above one is supposed to have the Horsehead Nebula. These kind of nebulas emit a lot of their light at the hydrogen alpha line of 656 nm, and modified cameras are often used and then give very red images. I wondered if it would be possible to detect at all through all that light pollution. With some extreme processing and noise reduction, this is what I came up with. The horsehead is in the upper left.      I believe the more purple color is caused by more contributions from lines of other elements. I have seen wonderful images from this region even from non-modified DSLRs, so I am looking forward to try this at a really dark site.





Then finally a 13 image stack of some starry sky (M103 star heap to the middle right), 60 sec, 300mm f/4.5 ISO 1600. The lack of purple fringing in highlights (that otherwise could cause discoloration of small stars) with this lens is really a treat.





On location: