Preparing to Photograph the 21 August 2017 Solar Eclipse? Practice, Practice, Practice

If you’re going to try to photograph the solar eclipse on 21 August, practice what you want to try out. Totality will last less than three minutes at best. You just have one shot.

I’ve been practicing and preparing for Monday’s solar eclipse by going over my equipment, trying photographic methods, and thinking what it is I’m really trying to do in seeing this event.

First and foremost, I want to experience the eclipse, not spend those few precious minutes fiddling with gear only to realize later that I missed the whole show. That means planning what I will and will not do, in detail.

I’m planning on setting up one camera on a tripod to take a series of wide angle shots that can be stacked afterward to make a composite image. This must be set up with a solar filter that can be popped off at the beginning of totality and then on again at the end. The good thing is that with that camera running on its own intervalometer it’s pretty much a hands off process.

A practice run of solar images captured with a dSLR running on internal intervalometer with a brown plastic solar filter. The sun covers its own diameter in the sky in about 2 minutes. This image is cropped from a larger composite lasting a fee hours. It represents about 50 minutes of the sun’s movement through the sky.

My most complex set-up will be a 125 mm Maksutov-Cassegrain telescope equipped with a mylar solar filter, set up on my old black EQ4 mount for viewing, twinned with a dSLR with 500 mm telephoto lens for detailed coronal photos at totality. I’ve been working out the basic details of exposure times this week.

A telescope equipped with a mylar solar filter twinned with a dSLR camera and a 150-500 mm telephoto lens, also behind a mylar filter. This setup will not follow the sun with accuracy: it will have to be corrected manually throughout the eclipse.

I’ll also have a video camera set on wide angle to record the overall setting. My fourth camera will be a “general purpose” dSLR to take photos of the event and my colleagues as it unfolds.

The main thing is to be able to set things up efficiently and then paying attention to the timing of the event. One key manipulation is to pop solar filters off of cameras during totality. I’m creating a checklist to keep my intended processes working minute by minute, with time built in to take the whole thing in.

Practice, practice, practice!

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Remote Astrophotography: Taking It On-Line

Since the time of Galileo four hundred years ago, astronomers have used telescopes to see the sky. Since 1839 people have tried to take photographs through telescopes. Now, anyone with an internet connection – and a credit card – can take their own photos through professional-grade telescopes.

It’s called remote astrophotography, and I’ve been getting interested in giving this a try. I haven’t done so yet myself, mostly because I don’t have a good home internet connection yet. This seems to be a good reason to get one, and I hope to report back later this winter with some results of my own. In the mean time, I thought I’d report here on this intriguing idea.

A variety of companies are now operating telescopes in places with good conditions for astronomy and offering them up on-line, with equipment and software that allows paying users to control them remotely. What’s more, these set-ups are designed for astrophotography. The telescopes are equipped with specialized CCD cameras designed for astrophotography. The lure of remote astrophotography is not just being able to use these telescopes to see on-line. They can take amazing photographs and deliver them to your home computer.

Costs for this service range from an annual subscription of around $150 at SLOOH Space Camera (http://www.slooh.com/slooh-home.php) to a fee per use running up to $100/hr at LightBuckets (http://www.lightbuckets.com/index.php), MyTelescope.com (http://www.mytelescope.com/index.html), or iTelescope (http://www.itelescope.net/). There are likely others out there, too.

A NASA image of M51 and NGC5194.

A NASA image of M51 and NGC5194. M51, a magnificent spiral also called the Whirlpool Galaxy, is on the left. It is interacting with M51b or NGC5194, the dwarf galaxy on the right.  They are located south of Canis Major, in the constellation Canes Venatici. These galaxies are well within the scope of amateurs to image. An astrophotograph of these galaxies taken by amateur astronomer Martin Pugh won the 2012 Astronomy Photography of the Year Award. (See this link for the contest: http://www.universetoday.com/97469/the-universe-shines-for-astronomy-photographer-of-the-year-winners/)

In some cases, users have to download specialized software like CCDCommander (http://ccdcommander.com/) that gives users complete control from their desktops, and even allows pre-programming of the functions of the telescope.

There are several reasons why remote astrophotography is very attractive. One of the most important from an image quality perspective is that the telescopes involved can be set up in remote locations with excellent dark skies and clear weather, such as in Arizona or even Chile. Users don’t have to make a trek to those locations to take advantage of the conditions. Another big consideration is cost. The camera, telescope, mount, and observatory systems set up by these companies can easily be worth $15,000 to $20,000 each or more. Renting some time on these set-ups is a lot more attractive than having to buy hundreds of kilos of very pricey kit. Furthermore, the remote telescopes are set up and maintained by experts. Even if money was no object, there’s a very long technical learning curve to really be proficient with big ‘scopes – years in many cases. Renting sidesteps all of that and can give you excellent results in hours, not years.

Remote astrophotography is not limited to by-the-hour rentals, either. Some people who are able to purchase their own telescopes chose to have them installed at remote locations for the same reasons as these rentals are located there: better sky conditions than at home. Clearly an expensive proposition, these private observatories have the potential to allow for many hundreds of hours of observing and photography that would be impossible under any circumstances other than moving to a dark sky location. Some people are able to take up that option, too.

Where To Go From Here?

While I’ve been interested in astronomy for over forty years, it’s only in the past year and a bit that I’ve returned to that interest in any sort of “serious” way as an amateur. I’ve been poking around at various telescope shops, getting to know some other amateurs in my area, and taking a lot of nightscape photos. I’ve even started taking a few photos of the moon and Jupiter with the equipment I have. Now what?

The sky is a big place. A simple calculation gives you an idea of just HOW big it is – and I’m not talking about how deep it is in time/distance. Consider first the moon. The moon is pretty big. It has a surface area about the same size as the continent of Africa, although we only can see about half of it from Earth of course. With the existing small telescopes I have I can make out features perhaps 5 km across if the lighting is right. The surface of the moon is about 38,000,000 km^2 (km^2 means “kilometer-squared or square kilometers) so if I can see half of it (in total) that’s about 19,000,000 km^2. A crater 5 km across has a surface area of about 19.6 km^s – so that little crater is just about 1/100,000 of the visible face of the moon. The whole visible surface is a lot of territory (or lunatory) to consider. Of course, it might be better to consider the visible disk of the moon, not the near hemisphere for a comparison like this. A disk with the radius of the moon would have a surface area of about 9,500,000 km^2, so the ratio would be about 50,000 craters-worth of area to explore. Still a lot! A purist would try this with angles but the answer would be the same as the disk area sketch.

The thing is, the moon is actually SMALL compared to the visible celestial sphere. Our eyes are drawn to the moon at night, but the reality is that it’s only about a half a degree across. The whole celestial sphere, encompassing 360°, has an area of approximately 41,253 °^2 (according to a Wikipedia entry on the angular area of the celestial sphere). The moon’s disk as an angle is about 0.2 °^2 – so it would take 206,000 moons to fill up the visible area of the sky! (The sun as virtually the same angular diameter as the moon – that’s why we can have such stunning total solar eclipses – so the same thing holds. The sun, so dominant in our sky, covers only about 1/200,000 of the visible celestial sphere. From the surface of the earth only about half of the celestial sphere is visible as the sky, and the sun is about 1/100,000 of it).

The moon photographed from Hamilton, Ontario, on 2012 12 19 2125 EDT with an 80mm refractor and Nikon D5100 at prime focus.

The moon photographed from Hamilton, Ontario, on 2012 12 19 2125 EDT with an 80mm refractor and Nikon D5100 at prime focus. Relatively simple equipment can take nice photos – but if you are interested in going further, what’s the next step?

The sky, then, has room for 200,000 moon-faces, and my little telescopes can show me details 1/100,000 of the moon’s surface. It’s overwhelming – and full of rich detail. From massive galaxies to wispy nebulas and sparkling star clusters, space beyond our little solar system is one of the richest treasures in nature. How luck we are that we can actually see it! If our solar system was within a more complex part of space we might not have as good a view as we do. Then again, it’s a fair bet that the more “interesting” places in space are far more risky too. Our fair wee planet has had less than five billion years of life so far, and only a few major boo-boos (like the asteroid impact that killed the dinosaurs – Ooops!).

So, back to the point of this ramble. As a (re)budding amateur astronomer, where do I start? I’m faced with this question because I’m looking seriously at upgrading some of my equipment, and different telescopes do different things. Do I make use of my existing optics and improve my ability to point and shoot, with a better mount and camera? Do I invest in a better optical tube (the actual “telescope” part)?

To some degree a telescope is a telescope. There are some basic characteristics everyone needs to consider when they are thinking about this kind of thing. One of the most important is portability. Like a lot of people, I live in a small apartment; I don’t have a garage or basement for storing large pieces of kit, and I don’t have my own space for a shed or observatory. So, compact and rugged is good. I’m also watching my budget (gulp). And, of paramount importance to me, I want to embark on something of a path in learning astronomy, not just grabbing at big telescopes because they’re cool! (and they are cool, and I’m a telescope geek).

I’m thinking I’ll start in the neighborhood this year, seeing what I can see – and photographing what I can photograph close to home in the “planetary” range – the sun, moon, and planets. This narrows things a bit, and is also a good choice for an urban dweller. Despite light pollution in cities, our own solar system is still quite observable from our sidewalks and parks because the objects are so bright. The existing ‘scopes I have – an old 80 mm refractor and a 130 mm “starter” Newtonian reflector – will do for now. What I need to do is to consider in the short term is what’s under the telescope and what’s attached to it.

Telescope mounts are important and perhaps underappreciated parts of the whole “system.” A heavy, capable mount makes viewing anything much easier. A lightweight mount only has the advantage of light weight. Small mounts shake. If you adjust a small telescope on a light mount it can take five or ten seconds or more for the resulting vibration in the camera to dampen out. So, I’ll be paying attention to mounts.

Cameras are at the other end of the process. There are some things I can do with my dSLR cameras, but the best images today are actually being taken with cameras that are much simpler than a dSLR but are designed to be used with a telescope – and a computer. Derived essentially from webcams, most cameras that work brilliantly for planetary photography by amateurs have small-seeming sensors – often less than a megapixel. They are also specialized in two other ways. They often have a built-in cooler, to help control internal camera noise – and they are often monochrome. Yes, black and white. You can do a lot in black and white, and you can get colour images by taking a series of monochrome images through coloured filters. The image files (often actually captured as short video segments in AVI format) are then processed with some ingenious computer software to create stunning, sharp images. So, I’ll also be looking at a small, specialized camera designed for planetary imaging. By starting with a camera and a sturdier mount, I can get going and will consider upgrading the optics a little later.

I’m also sure that there will be lots of opportunities to peek out past our solar system in the coming year. I’m going to be making visits to observatories, star parties, and other events to soak in more of deep space – and of course to be able to make reports here at Pine River Observatory! And I’ll be spending time under the night sky doing wide-field photography and just wandering around the stallar back-yard with binoculars and a good star guide. There are many lifetimes of space out there to enjoy.

© 2012, David Allan Galbraith