No-Tools Telescope Collimation

Telescope front view

For optimum performance, precisely aligned optics are a must. Luckily, achieving this goal doesn't have to be difficult.

Most telescope users know that the only way to get every last drop of performance from a reflector telescope is to ensure that the optics are in good collimation. Here's a method that's simple and doesn't require tools or even a centre-dotted primary mirror.

In the May/June 2014 SkyNews

Cover image

The Moon is a feast of telescopic detail, but even so, some regions offer more to chew on than others. In my regular On The Moon column, we explore the many fascinating features found near the cartographic centre of the lunar disc. There you will find a pair of rille systems and evidence of the Moon's violent early history.

For more about what’s in the current issue, visit

In the May 2014 Sky & Telescope

Cover image

In this issue's Binocular Highlights column, we explore the strengths and weaknesses of binos by paying a visit to Coma Berenices.

My Telescope Workshop column this month focuses on making a featherweight front end for your Newtonian reflector. Science-fiction writer and ATM Jerry Oltion has incorporated several great weight-reduction ideas into his latest scope.

To find out what else is in the issue, visit S&T’s web site,

Happy reading — and as always, your comments, questions, and suggestions are welcomed.

In the April 2014 Sky & Telescope

Cover image

Spring skies are populated with faint, distant galaxies. But if you’re a binocular observer living in a city or a brightly lit suburb, this can be a bit of a dry time. So why not give in and have a look at something that’s both bright and nearby: the full Moon. In this issue's Binocular Highlights column, I describe some of the don’t-miss full-Moon sights.

Building the Outback Travelscope

Me at Uluru

Me, the Outback Travelscope, and a bloody big rock.
(Photo courtesy George Brandie)

When I was preparing to travel to Australia for a total solar eclipse and some dark-sky observing sessions in the Outback, I decided it was finally time to rebuild my 8-inch travelscope so that it could go into my suitcase and arrive safely at my destination.

Getting the Most From Astro Binoculars

Bino user

Binocular stargazing is full of surprises. Sometimes you stumble across a pretty cluster and wonder how you’d previously missed it. Other times, you hunt and hunt for a galaxy listed at 8th magnitude, only to come up empty handed. It’s enough to make you wonder — what makes one object a binocular standout and another difficult challenge? Compiled here are the five most important factors that determine whether or not a deep-sky wonder will turn out to be binocular trash or treasure.

The Top 5 Comets of the Past 20 Years

Comet Hale-Bopp

Magnificent Comet Hale-Bopp on April 3, 1997. It is unquestionably one of the finest comets of the past two decades, but is it the best one of all?

Few celestial objects excite the imaginations of stargazers and the general public like a good comet. The recent apparition of Comet ISON prompted me to reflect on the all the comets I've been fortunate enough to see in the past 20 years. There have been some stunners, some surprises, and a few that could have been great, but fell short. Here’s my (highly subjective) pick of the five most interesting and spectacular comets from the past two decades.

Great "New and Improved" Astro Web Site

Just a quick note to all my readers to check out the new and improved SkyNews.caweb site. I’m happy to say that I get to be the site’s editor and work with some of the best astronomy writers in the business, including Terence Dickinson, Alan Dyer, and Ken Hewitt-White, to name but three. One item I hope you’ll find of particular interest is my regular “This Week’s Sky” column, which will highlight the most interesting observing events over the coming seven days. Check in regularly and enjoy everything we have on offer!


Telescope Economics: To Build or To Buy?

Sam and scope

I built my 12.75-inch Dob for less than $700 — much less than a comparable commercially made scope would have cost. But is making your own scope always a money saving proposition? That's what inquireing minds (canine or otherwise) want to know.

For diehard ATMs, building telescopes is a way of life. But for others, the decision about whether or not to make a scope often hinges on economics. Will I save money building my own? The question shows up regularly in on-line forums and in my e-mail box. Before the emergence of a large-scale commercial telescope industry, the answer was a definite “yes!” But with the current abundance of low-cost, imported Dobs, and the increasing expense (and scarcity) of telescope-making supplies, it’s reasonable to wonder if it’s still possible to save a few bucks by going the home-made route. The prevailing conventional wisdom says “no,” but my own experiences suggest the answer isn’t as cut and dried as that.

Build This Simple Binocular Mount

Bino mount in use

Requiring only a few parts, this simple and effective setup provides stable images for detailed views of the night sky.

“This is the best binocular mount I’ve ever used!”

Those were the first words out of my mouth as I came indoors from testing my just-completed binocular rig. It’s rare that I build something that actually works better than expected, but finally I’d come up with a binocular mount that provides steady views, is easy to use, very portable, and simple to build. It was a good night.

A Beginner’s Guide to Collimation

Front view

I’ve been building and using telescopes for more than three decades and I’ll share with you a secret: collimating a Newtonian reflector is easy. So why does it seem so difficult when you’re just starting out? Probably because you’ve done your homework by Googling the subject and have read and re-read everything you’ve found. And now, you’re lost in a forest of information — some of it contradictory, some of it densely technical. Truly, sometimes less is more.

Build a Hinge Tracker for Astrophotography

Scorpius stars

This image of the Scorpius Milky Way was captured from Costa Rica with a DSLR camera and the simple hinge tracker mount described here.

If you have a DSLR camera and are interested in astronomy, you’ve probably considered dipping a toe into the astrophotography waters. But a camera is only part of the equation — for exposures longer than a few seconds, a tracking mount is usually necessary. Unfortunately, most suitable mounts are relatively bulky, or expensive, or both. But not the hinge tracker. It costs less than $10 to build, takes less than an evening to assemble, and requires no batteries. And best of all, you can put one together even if you’ve never built anything more complicated than Ikea furniture.

My Photo Web Site

FilmAdvance title

I invite everyone to check out my web site,
In addition to astronomy, photography is a big passion of mine. So, I started as an outlet for my photographic explorations. There will inevitably by some astronomy related content posted there, but mostly it’s about seeing the universe through the lens of a camera, instead of the eyepiece of a telescope. Look in on it from time to time to see what I've been up to with my cameras and darkroom. Enjoy!

Review: Canon’s Image-Stabilized Binoculars

Canon ISB

Combining optical excellence with rock-steady views, Canon's image-stabilized binoculars are a stargazer's dream come true. But is one best for you?

For a long time, 7×50 or 10×50 binoculars were considered the best choice for stargazing. Such binos are relatively lightweight, inexpensive, and capable of delivering fine wide-field views of the heavens. But most people find that hand-held 10×50s represents the upper limit of the weight and magnification comfort zone. Models featuring higher magnification or more aperture require a tripod or dedicated binocular mount for steady views. Even 10×50s rarely work near their potential without support. Unfortunately, such devices ensure that an instrument much loved for its portability and convenience becomes encumbered with as much paraphernalia as a small telescope. Enter the image-stabilized binocular.

The Big Red One: My Optimized 6-inch f/9 Reflector

Big Red 6-inch f/9

Attention to detail is what separates a regular Newtonian reflector from one optimized for high-contrast performance. This 6-inch f/9 uses every trick in the ATM’s book to deliver superb planetary and deep-sky views.

This was the first telescope I made using my own optics. Like most telescope makers, I got started the easy way, by building Dobsonians with mirrors ground by others. But one day I got bit with the mirror-making bug. I blame my friend Lance Olkovick, our local club’s mirror-making ace. But why a long-focus 6-inch? At the time I was a hardcore Jupiter junkie and was convinced that a long-focus Newtonian would deliver excellent views of my favourite subject. I also wanted to prove a point.

Exploring Low-Power Limits


The old saying that less is more rings true for telescope magnification, but there are many factors to consider before choosing your ultimate wide-field eyepiece.

Low-magnification views of the night sky can be breathtaking. It’s only with low power that we can fully appreciate the splendor of the Pleiades, the foggy expanse of the Andromeda Galaxy, or the wispy filaments of the Veil Nebula. But if discussions on internet forums are anything to go by, there's a lot of confusion out there about how magnification, field of view, and exit pupils relate to each other. And without understanding these factors, you might end up shortchanging your telescope’s low-power capabilities.

Beat the Heat: Conquering Newtonian Reflector Thermals — Part 1

Newtonian thermal gradient

What you need to know when it comes to optimizing your scope’s thermal behavior.

Generations of backyard astronomers have debated why, inch-for-inch, the performance of a high quality refractor usually edges out an equal-quality Newtonian reflector. This disparity is most apparent when viewing low-contrast planetary detail — the images in a good refractors often have a touch more snap to them. Is there some intrinsic shortcoming in the design of the Newtonian reflector that makes this inevitable?

A Tracking Platform for Astrophotography

Tracker lead image

This simple, easy-to-build mount provides the perfect introduction to long-exposure astrophotography.

Round stars. That’s the difference between astrophotos captured with a camera that tracks the sky’s motion versus one that doesn’t. Traditionally you’d make a tracked photo by placing your camera piggyback on a telescope with a motorized equatorial mount. But that’s a lot of equipment to deal with if all you want are some nice-looking constellation portraits or a shot of a newly discovered comet — especially if you have to travel to reach your favorite dark-sky destination.

Understanding Binocular Exit Pupils

Exit pupils

Do binoculars with small exit pupils really produce dimmer images?

One binocular specification that seems to generate more than its share of contradictory advice is exit-pupil size. I've often seen statements to the effect that you should avoid binoculars with smaller exit pupils because the view is “dimmer” than in models having larger exit pupils. But is this actually true, and more importantly, should it factor into your binocular selection?

Sizing Up the Newtonian Secondary

Secondary mirror

Too big, too small, or just right? Making sure your reflector’s secondary mirror is the correct size is a straightforward task.

The Newtonian reflector has many strengths, not the least of which is that it consists of just two elements: a precisely shaped paraboloidal primary mirror and a flat diagonal secondary mirror. Yet for all its intrinsic simplicity, confusion abounds when it comes to the optimum size of the diagonal. Many amateurs, and apparently even some telescope manufacturers, seem unsure as to how to choose the correct size for the diagonal. So how big should it be? That depends on several design parameters and some personal preferences.

Syndicate content