Telescope Reviews: Binocular Observing -- Getting Started

Binocular Observing – Getting Started

Here are a few suggestions to help the beginner get started with night sky binocular observing. The suggestions are grouped into five sections.

Sky Orientation
Sky Atlases
Observing Guides
Binocular Optics
Interlibrary Loan

. . .

Sky Orientation
The night sky changes by hour and by season. All of the night sky objects (Moon, planets, stars, clusters, galaxies, and nebulae) follow an East-to-West path through the night sky, which is a result of the Earth’s rotation. The sky itself is divided into 88 constellations. Not all of the constellations are viewable from the northern hemisphere. Some can only be viewed from southern locations, such as South America or Australia. It helps to imagine you are standing on a golf ball (Earth) inside a large beach ball (Universe). When you look up at the sky, you are looking at the inside of the beach ball. The beach ball is stationary, the golf ball rotates.

But first, you need a night clear of clouds to be able to observe the objects in the night sky, and it helps to get away from light pollution. Weather forecasts help predict sky conditions. I like to use the NOAA National Weather Service, because the type of data reported is consistent from location to location. Start with the main website for NOAA http://www.noaa.gov/ and enter the city, state or zip code for the weather reporting geographical area. When you click “Go” you will be taken to the forecast webpage for that area. Here is the NOAA NWS webpage for Fort Sumner, New Mexico http://forecast.weather.gov/MapClick.php?CityName=Fort+Sumner&state=NM&site=ABQ&textField1=34.4781&textField2=-104.237&e=0 . There is a lot of information on this webpage, which has links to more weather information. Two links to point out are the NWS Regional Office link in the top left corner (NWS Albuquerque, NM is the NWS Regional Office for Fort Sumner) and the 3-day history link in the Current Conditions block on the right.

For night sky observers, another useful website is Clear Sky Clock. Here is the Clear Sky Clock link for Fort Sumner, NM http://www.cleardarksky.com/c/FtSmnrNMkey.html?1 . The data in the black block is the key forecast data, which comes from a service in Canada. To the right of the black block are links to other clear sky clock locations. Here is the link for the clear sky clock locations in the state of New Mexico http://www.cleardarksky.com/csk/prov/New_Mexico_charts.html . Please notice the color squares listed next to each location. These are indicators of light pollution for each location. Now, select one of the clear sky clocks in the state list. When the clear sky clock comes up, notice the section below the black block called Nifty Links. First, click on the Light Pollution Map link and scroll down. Here you will find the key to the colors used to indicate levels of light pollution. The rule is simple—the darker the site, the more stars you see.

Two helpful links in the Nifty Links section (below the black block) are the Sun & Moon Data and Star Map links.

The Sun & Moon Data gives you rise, transit, and set times for the Sun and Moon. Transit is the term used when an object is due South (180 ° azumith). The Sun & Moon Data webpage also gives disk illumination and phase data for the Moon, as well as links to additional information.

Go back to the Nifty Links section on the Clear Sky Clock. The Star Map link shows the Sky Above, a reduced scale view of the night sky for a specific location, date, and time. Notice the lines on the map--these are the constellation stick lines (or stick figures). Also notice the orientation on the perimeter of the map (North, East, South, and West). East and West are reversed from a land map. Scroll down to adjust the location coordinates, date, or time. By changing the hour, you can watch the constellations move across the night sky, in a similar way they move across the night sky above your head throughout the night. You can also identify the location of the constellations during specific day hours. By changing the month, you can see how the constellation positions change from season to season. You can zoom at the Sky Above map by placing your cursor on a specific location and clicking your mouse. When you zoom in, you can identify the names of constellations. Keep zooming, and you will get the names of bright stars and objects.

We sometimes call maps like the Sky Above map a planisphere. You can purchase paper or plastic planispheres to take outside. You rotate the parts of a planisphere to tell you what constellations, major stars, and objects are in a specific section of the night sky, by date or time. My favorite planisphere for outside field use is the The Night Sky (plastic version, large size) available from David Chandler http://www.davidchandler.com/nightsky.htm . His small plastic planisphere, though not as detailed as the large size, is ideal for stuffing in a pack or pocket.

Dark Sky Finder http://www.jshine.net/astronomy/dark_sky/ is a website to help you find dark skies close to your location. This website uses the same color key for light pollution and can be zoomed to locate dark observing sites on a road map.

Sky orientation also requires a field compass for locating specific azimuth directions, such as North, East, South, and West. This is particularly helpful if you are observing in an unfamiliar site.

. . .

Star Atlases
For many observers learning the night sky takes several years. A sky atlas can shorten the learning curve for most of us. There are several paper atlases to choose from. As with anything, each atlas has specific pros and cons, as well as devoted followers. One difference that separates various atlases is scale. Just like land maps, a large scale makes it easier to identify objects on the map. Unfortunately, large scale sky atlases are bulky. A very useful website is http://www.skymaps.com/store/cat01.html , which lists many of the current sky atlases, as well as descriptions and chart samples.

I enjoy sky atlases. I have 16 paper sky atlases in my personal library. The seven I use most frequently are listed below with their atlas scale. For my personal use, I classify these seven atlases by binocular size.

The Photographic Atlas of the Stars

The Cambridge Star Atlas

Pocket Sky Atlas

The Milky Way Atlas

Cambridge Double Star Atlas

Sky Atlas 2000.0

Uranometria 2000.0, 3 vols.

The Photographic Atlas of the Stars is a beautiful sky atlas with color photographs on the right hand page and star charts with labels and grids on the left hand page. Unfortunately, this atlas is no longer in print, but good copies can be obtained through the used book market available online from Amazon.com, Bookfinder, or American Book Exchange (ABE). Incidentally, you can save yourself several dollars by purchasing astronomy publications from the used book market, as long as you purchase books described as “very good” or “fine” condition. Many of the photographs for The Photographic Atlas of the Stars were taken from Star Hill Inn, Las Vegas, New Mexico http://www.angelfire.com/stars2/bwolfe/starhillvacation.html . Here is a recent CN thread inquiry into Star Hill Inn http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/3349630/Main/3349504 .

Another beautiful atlas is Glen LeDrew's The Milky Way Atlas with color photographs on the left hand page and sky charts on the right hand page. Glenn is a regular here in the CN Binoculars Forum. Among his many binocular projects, he usually is working on one or more custom binoculars that he designs and builds himself.

Many observers use one or more software sky atlases. Some of the simple software atlases are available as free downloads on the Internet. The better software atlases, as expected, come at a cost. The software atlas I prefer is Sky Tools 3 (Crinklaw, Ver. 3.0, 2009), which offers many features, including printable custom field maps, custom views by eyepiece or binocular specs, object location, object information, zooming for various magnification views, custom observing lists of objects, logging database for recording observations, and much more. With this software program, I can view on my computer screen the same view as I will see through my 7x50, 10x50, 16x70, or 22x85 binoculars. I can also print custom field charts (by binocular size) to take outside and check off. Later, the custom field charts can be placed in a 3-ring binder (using sheet protectors to avoid punching holes in the charts) as a record of my observations. Some observers take their laptops to observing sites and cover the screens with red cellophane wrap to protect night vision. Many software atlases have a night vision option to present data and charts in red.

No doubt, software atlases have raised the bar significantly for sky atlases.

. . .

Observing Guides
Observing guides are useful for studying the night sky, constellation by constellation, or by object type. Observing guides generally tell you how to find specific objects and provide a short description of what you can expect to see. Some guides present information on equipment. There are many observing guide titles. Below are titles of observing guides from my personal library, organized by optic size. The titles are listed by order of publication date, with the most recent edition listed for titles with a publishing history.

Binocular observing guides:

Touring the Universe through Binoculars

Exploring the Night Sky with Binoculars

Binocular Certificate Handbook

Binocular Highlights

Binocular Astronomy

John Flannery’s Binocular Certificate Handbook is in pdf file format and can be saved or printed from a computer. The guide is available online at no cost from several websites. Here is one link where you can obtain a copy: http://www.minds.may.ie/~astro2/IFASData/IFASBinocularHandbook.pdf .

Small telescope observing guides:

Turn Left at Orion

Star Watch

Celestial Sampler

Medium to large telescope observing guides:

Burnham’s Celestial Handbook, 3 vols.

Observing Handbook and Catalogue of Deep-Sky Objects

Star-Hopping for Backyard Astronomers

Deep-Sky Wonders

The Night Sky Observer’s Guide, 3 vols.

The Backyard Astronomer’s Guide

An interesting and easy introduction to astronomy is 365 Starry Nights (Raymo, 1982) -- no big words or complicated math, lots of illustrations, and a short entry for each night of the year.

Most observers read their atlases and guides outside by a red flashlight to preserve night vision (dark adaptation). A few observers prefer the brighter illumination delivered by a green flashlight, reasoning the brighter light for reading print information outweighs the temporary reduction of night vision. During the observing session, if you find you move frequently from outdoors to inside (bright lights) or observe close to a road or street traveled by cars (head lights), you may want to obtain a pair of red goggles. I start wearing red goggles in the house 30 minutes prior to observing and during setup, and generally keep them on top of my head, close at hand, during the complete observing session because car headlights suddenly shine in my back yard due to a curve in a nearby road.

Another great resource is the website for Sky & Telescope Magazine, which has a wealth of information for the beginner night sky observer. Some of my favorites from the S&T website are

Getting Started in Astronomy

http://www.skyandtelescope.com/howto/basics/3308331.html?c=y&page=1

This Week’s Sky at a Glance

http://www.skyandtelescope.com/observing/ataglance/63143987.html

Interactive Sky Chart

http://www.skyandtelescope.com/s?action=login

News Highlights

http://www.skyandtelescope.com/news

Learning the Sky

http://www.skyandtelescope.com/letsgo/learningthesky

Stargazing Basics

http://www.skyandtelescope.com/howto/basics

Celestial Objects

http://www.skyandtelescope.com/observing/objects

Beginner binocular observers can also turn to another type of binocular guides--people, not books. Here at Cloudy Nights, we are fortunate to have several binocular observing experts that will gladly offer suggestions in the forum threads, as well as answer personal messages (e-mails) and speak from various online podiums. At the risk of offending any of my online friends, I will recommend three experts for the beginner binocular observer. There are many other experts, but I will limit my list to the following three people who have devoted their career to binocular observing.

Phil Harrington

http://www.philharrington.net/

Binocular Universe

http://www.cloudynights.com/category.php?category_id=182

Gary Seronik

Binocular Highlights

http://www.garyseronik.com

Ed Zarenski

Binocular Tests, Research, and Reviews

. . .

Binocular Optics
A single pair of binoculars and a tripod is really all you need for binocular observing.

First, let me talk a minute about the tripod. You may own a tripod, but not observe with it during every observing session. In fact, most of your observing sessions may take place without setting up a tripod. This can be a mistake for the beginner binocular observer.

In my opinion, the tripod is most beneficial in helping the beginner observer learn the night sky. The technique I suggest is mount your binoculars on your tripod and aim at a specific star pattern or constellation, step aside to consult a star atlas or observing guide, and return to the mounted binoculars to compare the atlas view with the actual binocular view. The tripod is also beneficial at steadying heavy binoculars or giving the arms a rest during long observing sessions.

The selection of binoculars is a bit more complicated because of observer differences and site differences. Many binocular observers do not agree upon the basic binocular size. Some prefer the basic binocular be 10x50, while others defend 8x42 or 7x50.

If you observe with one pair of binoculars, and never plan to use a second binocular in your night sky observation, I recommend that one binocular be 10x50.

On the other hand, if you observe with two or more binoculars, I recommend a wide angle 7x50/8x42 (FOV of 7.5° or greater) and 15x70. The 7x50/8/42 is good for sweeping the skies and locating specific constellations and star patterns. Whether the first binocular is 7x50 or 8x42 depends upon two issues: observer’s eye pupil and level of light pollution in the sky. Generally, the 7x50 should only be used by observers under dark skies with eye pupils that open to 6.5mm or larger. All other observers should select a wide angle binocular in the 8x42 range.

In my opinion, the observer will enjoy greater flexibility with two binoculars (8x42 and 15x70) than a single binocular (10x50). I call this doing the binocular two-step: the lower power for wide viewing and the higher power for deep viewing. Some observers prefer to do the three-step by adding a 20x to 25x binocular to go even deeper.

My binocular observing of the night sky (by binocular size) breaks down as follows.

Finally, when it comes to binocular optics, do not set your expectations too high. Do not think you are going to see the wonderful sights in the astronomy magazines or websites. You will not. Binocular observing is best for sweeping night skies, locating pointer stars, observing star patterns, and studying open star clusters. If you want to observe planets, globular clusters, nebulae, and galaxies, it may be best to use telescopes—refractor, reflecting, or combination models. Sure, you can see a few globs, nebulae, and galaxies with binoculars, but you will generally not see more than a speck or smudge in the binocular eyecups. Binocular observing offers convenience, mobility, and comfortable observing. Things we all enjoy.

. . .

Interlibrary Loan
Astronomy requires access to lots of information. Astronomy information in print format, such as books, can be expensive. To keep your observing costs down, you can take advantage of your public library’s interlibrary loan service. This is a free service and a great way to examine multiple book titles on a specific subject. Most libraries do not advertise this service and you generally work with someone at the reference desk to order the titles. Some libraries require you to fill out a form, but many have the service available online. You will need a library card in good standing (no overdue books!).

Public libraries work with a service called WorldCat http://www.worldcat.org/ to locate the requested titles from other libraries. Expect a lead time of 3-6 weeks from the time you fill out the form until the time the titles arrive in your library. Your library will notify you when the titles arrive and you should be able to check out interlibrary loan books for 3- to 4-week time periods.

Interlibrary loan is a great service and a great way to learn about astronomy, or any other topic of interest. At any given time, I generally have two or three book titles on interlibrary request through my public library.

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Bob
38°N

Edited by BobinKy (10/04/09 12:18 PM)