t = 0

Working with constellations in DOCdb

 posted: 71 days ago, on Sunday, 2015 Mar 15 at 10:00
 tags: astronomy, deep sky, docdb.net.

DOCdb now has constellations as a special type of "object", making planning your observing session even easier. This step-by-step guide shows how easy it is to use.

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 t <= 0

DSLR Photometry Experiments. Visualizing what stacking does

 posted: 78 days ago, on Sunday, 2015 Mar 08 at 03:44
 tags: astronomy, astrophotography, DSLR photometry, Canon.

The reduction in noise following stacking of DSLR images of stars is illustrated.

(photo: HD 121228, cropped from a single frame (left) and from a stack of 17 frames (right).)

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DSLR Photometry Experiments. A dark curiosity

 posted: 78 days ago, on Sunday, 2015 Mar 08 at 02:34
 tags: astronomy, astrophotography, Canon, DSLR photometry.

A puzzling (and worrying) feature of dark frames, taken with a Canon EOS 60D, is presented. The author is desperate for a solution!

(photo: Figure 1. File size of a sequential series of 40 dark frames taken with a Canon EOS 60D (ISO 1600, 9-s exposure time, CR2 raw format).)

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DSLR Photometry Experiments. 4. How many darks?

 posted: 79 days ago, on Saturday, 2015 Mar 07 at 23:58
 tags: astronomy, astrophotography, DSLR photometry, Canon.

The effect of the number of dark frames subtracted from a light frame on the signal-to-noise ratio (SNR) of stars is investigated. The conclusion is that applying a single dark frame gives a substantial improvement in the SNR of stars, while applying additional dark frames gives only a very small improvement.

(photo: Five stars selected for S/R measurement.)

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Chris Forder's Star

 posted: 82 days ago, on Wednesday, 2015 Mar 04 at 22:26
 tags: astronomy, astrophotography, Walter.

Sitting snuggly next to Mimosa (beta Crucis) is one of the reddest-known stars.

(photo: DY Cru)

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LLAP

 posted: 86 days ago, on Saturday, 2015 Feb 28 at 10:47
 tags: sci-fi, obit.

Leonard Simon Nimoy (1931 March 26 - 2015 February 27)

(photo: LLAP Leonard Simon Nimoy)

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Museum Night 2015, Iziko, Cape Town

 posted: 87 days ago, on Friday, 2015 Feb 27 at 07:39
 tags: astronomy, outreach, Moon, Iziko Museum Night, Cape Town, Walter.

Photos from Iziko's Museum Night (Cape Town) on 2015 Feb 26.

(photo: Scenes from Iziko Museum Night)

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Astronomical highlights during 2015

 posted: 89 days ago, on Wednesday, 2015 Feb 25 at 07:51
 tags: astronomy, outreach, almanack, astronomy media, Sky Guide.

The best of the best in the sky for the year.

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The Summer 2015 Southern Star Party

 posted: 89 days ago, on Wednesday, 2015 Feb 25 at 05:34
 tags: astronomy, deep sky, observing equipment, star party, astrophotography, Milky Way, Southern Star Party, events, Ed Foster.

A photo gallery from the Summer SSP

(photo: SSP terrain)

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Walter

 posted: 171 days ago, on Friday, 2014 Dec 05 at 09:08
 tags: astronomy, observing equipment, Walter, Martin Lyons.

First-light pics of Walter.

(photo: Walter montage)

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2015 Astronomy Wall Calendar

 posted: 215 days ago, on Wednesday, 2014 Oct 22 at 23:29
 tags: astronomy.

An attractive astronomy wall calendar for 2015, specially for the southern hemisphere!

(photo: 2015 Astronomy Wall Calendar for southern Africa)

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Pearls of the Southern Skies

 posted: 244 days ago, on Tuesday, 2014 Sep 23 at 18:03
 tags: astronomy, deep sky, astrophotography, history, Dieter Willasch.

Finally! Published in 2014 September by Firefly Books (Canada).

(photo: Pearls of the Southern Skies cover)

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Moon occults Saturn (2014 June 10)

 posted: 348 days ago, on Wednesday, 2014 Jun 11 at 15:03
 tags: astronomy, astrophotography, occultation, Sir Brian, Moon, Saturn, Somerset West, Martin Lyons.

On Tuesday evening the Moon occulted Saturn. Story and pics after the jump.

(photo: Reappearance of Saturn, imaged by Richard Ford.)

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2014

 posted: 510 days ago, on Tuesday, 2013 Dec 31 at 08:12
 tags: events.

All the best for 2014!

(photo: :-))

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Nova Cen 2013 - the brightest nova this century

 posted: 534 days ago, on Saturday, 2013 Dec 07 at 10:11
 tags: astronomy, variable stars.

On Monday, December 02, Australian amateur astronomer John Seach (Chatsworth Island, NSW) discovered a nova in Centaurus, not far from beta Centauri.

(photo: Image by Auke Slotegraaf, Somerset West. 2013 Dec 20 04:27 SAST)

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Spotting the crescent Moon in December

 posted: 537 days ago, on Wednesday, 2013 Dec 04 at 06:27
 tags: astronomy, Moon.

Find the slender lunar crescent as it returns to the night sky over the next few days.

(photo: December 04)

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Dassiesfontein Farm Stall

 posted: 563 days ago, on Friday, 2013 Nov 08 at 13:00
 tags: photo diary.

On the N2 between Botrivier and Caledon lies an intruiging stop-over spot.

(photo: Dassiesfontein. 2013 November.)

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The best of the best in the sky for the year.

cool stargazing events

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