Venus and Neptune in the Evening Sky

In late January, the easily visible planet Venus was located in the same part of the evening sky as the dimmer and distant planet Neptune. I’ve never tried to photograph Neptune but this pairing of the planets was a good reason to do so.

Venus and Neptune in the evening sky (2020-01-28).
Venus and Neptune in the evening sky (2020-01-28).

The first attempt was taken on the evening of 27 January (shown below) and I was limited to very short exposures as I was using a standard tripod. The second attempt  was the following night from a better location and, more importantly,  I was using my equatorial mount star tracker so that I could follow the stars (or planets) for longer exposures.

The image at the top is the second attempt. High, thin cirrus clouds were beginning to move in from the west and I was hoping that the clouds might make some of the stars more colorful. What I got was an amazing corona surrounding the very bright planet Venus while stars and the dimmer Neptune appeared relatively unchanged.

Venus and Neptune in the evening sky (2020-01-27).
Venus and Neptune in the evening sky (2020-01-27).

The image above is from the first night of shooting and shows diffraction spikes around Venus. Examing these two images you can easily see how far Venus has moved in one night by comparing the position of Phi Aquarii (φ-Aqr).

Photographing the North America Nebula

The North America Nebula has been on my To-Photograph list for a while. I had made one quick attempt previously to see whether I could actually resolve it with my Nikon 85mm f/1.8 lens. That was successful so I was ready to try again when the situation permitted.

I finally found the time, the right weather, and the right conditions. I shot a sequence of seven, 120-second exposures.

There are many star-stacking software packages available and I’ve often used DeepSkyStacker (DSS). More recently I’ve been testing StarrySkyStacker (a macOS-only app). The results have been pretty good.

The stacking complete, it was time to work on the histogram. Again, there are many histogram stretching packages. I’ve been evaluating rnc-color-stretch, available from Clarkvision.com. rnc-color-stretch is a set of scripts that calls the davinci application (not to be confused with the DaVinci Resolve video editing software).

North America Nebula (NGC 7000)
North America Nebula (NGC 7000)

The result is shown above. My next attempt at shooting this Deep-Sky Object (DSO) will be with my recently acquired Nikkor 180mm f/2.8 AIS manual focus lens.

A New-to-Me lens for Astrophotography

I recently acquired a used lens that I plan to use for astrophotography. The Nikkor 180mm f/2.8 ED AI-S is well-known as an excellent lens for this purpose—assuming, of course, you get a good copy of the lens.

Pleiades (M45).
Pleiades (M45).

Jerry Lodriguss, over at AstroPix, has this to say about the lens:

The Nikon 180mm f/2.8 ED lens is a legendary lens, and with good reason. It’s performance for normal daytime photography is simply outstanding. And it is pretty darn good for astrophotography also…

I have been looking at used copies of this lens on-and-off for several years but have never actually been excited enough to purchase one. That is, until I saw one listed in MINT condition for an extraordinary price. The lens was offered by Tempe Camera and the store was close enough that I could drive down there in a few hours. Off I went…

And the lens really was in Mint condition. After a bit of checking and a few test shots I bought it. Now it was time for testing. On my first night my results weren’t that great but I attribute that to the fact that it was COLD and my fingers weren’t very good at getting sharp focus and it was windy causing the camera to shake resulting in blurry images.

So, I headed back out again the next night. I sought a location without wind and at a lower elevation hoping for warmer temperatures. Well, it wasn’t warmer but there was no wind.  And the results were pretty good. Comparing the results at various f/stops (f/2.8, f/4.0, and f/5.6) I could see how the image improved with smaller apertures. And a comparison with my very old Nikkor 80-200mm AI-S f/4 showed that the 180mm was better than the zoom lens at equivalent apertures.

I’m pretty happy with the quality of the lens and the price I paid. Now all I need is some clear skies to get out and do some more shooting.

 

Transit of Mercury—November 2019

The weather was perfect with clear skies and light winds in northern Arizona to photograph the transit of Mercury across the face of the Sun.

Transit of Mercury—11 November 2019
Transit of Mercury—11 November 2019

From Wikipedia: “A transit of Mercury takes place when the planet Mercury passes directly (transits) between the Sun and Earth, becoming visible against the solar disk. During a transit, Mercury appears as a tiny black dot moving across the disk of the Sun.”

Mercury is small so it is difficult to photograph a transit without using a telescope or large telephoto lens. I photographed the transit using a (1) full-frame Nikon DSLR and a 70–300mm telephoto zoom lens, and (2)a Panasonic Lumix FZ150 “bridge camera” with a 600mm [equivalent] zoom. The Nikon takes vastly superior images; the Lumix has more zoom. And the better results came from the Lumix.

The photograph above shows the first image taken as the Sun had partially cleared the cliffs. Subsequent images were stacked and aligned on this image so that it shows a sequence of positions during the transit.

Transit of Mercury—09 May 2016.
Transit of Mercury—09 May 2016.

The last transit of Mercury was 09 May 2016; the next will be 13 November 2032. The image above is from the 2016 transit.

Transit of Venus—05June 2012.
Transit of Venus—05June 2012.

Transits of Venus are easier to capture because Venus is much larger than Mercury and also closer to Earth. The last two transits of Venus were 05 June 2012 and 08 June 2004. The next transits of Venus will not occur until 10–11 December 2117 and 8 December 2125. Above is an image of the 2012 transit with a bird also “transiting” the sun.

Moon and Planets in the Evening Sky

On Monday and Tuesday (28-29 October 2019) the thin crescent Moon passed near the planets Venus and Mercury in the evening twilight sky. A check of The Photographers Ephemeris indicated that I could set up at Little Horse trailhead near Sedona and capture the thin crescent as it slipped between the spires of Cathedral Rock. Venus and Mercury would also be visible.

Ah, if only is was as easy as that. I never was able to see the crescent Moon.

A very thin crescent Moon sets behind Cathedral Rock.
A very thin crescent Moon sets behind Cathedral Rock.

But, wait! A closer inspection of the images shows that I did capture the crescent Moon. It was only 1% illuminated in a bright twilight sky. If you look carefully at the image and above the two people, you can just barely see a very thin crescent in the gap.

Venus and Mercury set behind Cathedral Rock.
Venus and Mercury set behind Cathedral Rock.

The next evening the Moon was 4% illuminated and higher in the sky making it an easy target. Venus and Mercury were below and the star Antares was to the left. Fitting all four objects in the image was the goal and I was successful. The only issue was the strong winds which resulted in some camera movement during the image capture.

Moon, Venus, Mercury, and Antares in evening twilight.
Moon, Venus, Mercury, and Antares in evening twilight.

I used Stellarium to determine how the Moon, planets, and stars would look at that time of the evening. I also used the Ocular plugin to show the field of view (FOV) of various lenses and focal lengths so that I could know, in advance, which lens would capture the whole scene. Very helpful!