A great deal of mystery and misconception surround the topic of observing the sun and solar eclipses, and while you should absolutely not look directly at the sun without proper protection, we here at B&H have got you covered on how to enjoy viewing the sun and, later this year, the solar eclipse. Read on to see what’s available for you, if you’re interested in investing in a dedicated solar telescope.
White Light or Narrow Band?
Right out of the gate, you need to decide: White light or Narrow-band (Targeted) viewing? For specifics about the difference, feel free to click on over to my Solar and Solar Eclipse Viewing 101. Suffice it to say that White Light viewing is probably the most popular and easiest to do. Essentially, it entails using a filter that screens out more than 99.99% of the visible light from the sun (and all harmful IR and UV radiation) so it’s safe to view. This differs from Narrow-band viewing, which filters all light except a very narrow wavelength of the spectrum to reveal extraordinary details that White light filters can’t resolve.
The Basic Gear
The first piece of essential gear you’re going to need is a pair of solar glasses. Why, you might ask, do you need glasses if we’re talking about telescopes? The simple answer is that at some point you’re going to need to look at where the sun is so you can start observing, so having a pair of protective spectacles will save the inevitable glance right into the sun and the possible blindness that can accompany such a lapse in judgement. Whether you’re setting up, aligning, or just doing general prep work, having reliable safety gear to protect your peepers is probably the most important item you’re going to have.
All things being equal, if you plan on using them more than once or twice, I’d recommend solar glasses because they will be more durable and hold up to multiple uses better than the cardboard frames of the shades. Personally, I have these from Celestron—and they came with a white-light filter for my DSLR lens and a 2017 solar eclipse viewing guide, to boot.
White Light
Most “dedicated” white light scopes are conventional nighttime scopes in disguise. They will usually have a removeable filter that fits onto the front of the optical tube to make them safe for solar observation. Since the sun is so large in the sky and intensely bright, your average solar scope is going to tend to have a smaller aperture and shorter focal length.
My absolute favorite white-light telescope for observing the sun is, hands-down, the iOptron Solar 60 kits. The scope is the same for all of them—a 60mm refractor with a removeable front solar filter. You get eyepieces and accessories so you can start observing right out of the box. But what makes these the ideal rig, for me, are the mounts that come with them. The mounts are small and compact, with internal motor drives for tracking and a 14,000-object database with full GoTo capabilities and alignment assistance. Packages include a standard GoTo mount or a GPS-equipped GoTo mount, with a standard accessory package or an imaging package that includes an eyepiece camera to stream images and movies to a laptop. Regardless of what package you get, the Solar 60 can be removed and a different OTA can be installed on the mount if you want to upgrade later (as long as the new OTA weighs less than 7 pounds—the payload capacity of the mount).
For something a little more portable and versatile, you can go with the Sky-Watcher Virtuoso. This is a deceptive multi-tasker that might (will) change your life in unexpected ways. Its table-top motorized mount comes with a competent 90mm Maksutov-Cassegrain telescope and a removeable front solar filter, plus an eyepiece and diagonal. So far, so good, right? But wait… there’s more! You also get a bracket to mount a DSLR, and another for a smartphone! The simple pushbutton controls enable you to track the sun, moon, and planets after properly aligning it, and it has a port to plug in the SynScan computer hand controller that you can acquire separately. But beyond tracking celestial bodies, the system can be used for terrestrial photography including time-lapse, panoramic shoots, skyscapes, and an array of other techniques. Plus, it can be tripod mounted by simply detaching the base and threading the mount onto a 3/8"-16 tripod. Fun, easy, and versatile. You’ll use it for more than just solar viewing.
For those more casual observers, Meade makes its EclipseView line. First up is a selection of tabletop reflector models, offered in 82mm, and 114mm apertures with short focal lengths for portability; a 76mm longer focal-length reflector on a full-sized tripod; plus a 60mm refractor, also with a full-sized tripod. These are complete kits, again, with removeable front solar filters, eyepieces, and accessories, so you can start observing right out of the box. All the mounts are manual alt-azimuth styles, so you must find and track objects by simply moving the mount by hand.
Targeted Wavelength
This type of observation targets a specific wavelength, as opposed to the entire visible spectrum, when using White Light filters. The most common is the Hydrogen-alpha (Ha or H-alpha). This is the most popular because hydrogen is the most common element in the sun, so it’s the easiest to isolate. Within the bandwidth, certain filters can narrow it down to specific portions for even tighter concentration. Again, if you need help understanding what etalons and tuning systems are, check out the primer Solar and Solar Eclipse Viewing 101. Take care when ordering any of these upcoming recommendations because some of them are special-order only, so don’t wait until the week before the eclipse to click the “Buy” button.
The venerable veteran in solar scopes, and for quite a while the only choice for consumer solar viewing, is the Coronado PST, made by Meade Instruments. A simple 40mm refractor style, it has a low-maintenance tilt-tuner for the etalon and comes with an eyepiece only. For mounting convenience, it has a standard ¼"-20 mount to fit onto most photo, video, or field tripods easily. Stepping up in size is the SolarMax II 60. A larger and longer scope modeled on the PST, you have options of single or double-stacked etalons with various-sized blocking filters. It utilizes the more precise proprietary RichView tuning system, so pulling it on-band will be a bit easier and you’ll hit your target bands faster. You can get just the OTA to put it on a mount or tripod that you already have, or you can get a kit that B&H put together that comes with a Sky-Watcher GoTo motorized mount and tripod. Like the iOptron mentioned up top, you’ll be able to swap the SolarMax 60 with just about any other OTA for nighttime use and take full advantage of the thousands of objects in the mount’s database.
Lunt Solar Systems’ 60mm or 80mm H-alpha refractors come in an array of configurations, depending on what you want to see and how you want to see it. Using the same backbone, you can get versions with single or double etalons, blocking filters from 6mm to 18mm, pressure or tilt-tuned etalons, even different focusers. You can get a sturdy 2" rack-and-pinion focuser to handle heavier loads for imaging systems; or a 2" Crayford-style that, while not as strong, offers much more precision without the often-annoying backlash common with rack-and-pinion rigs. Regardless of the version you choose, you’re going to get just the OTA and blocking filter—eyepieces, mounts, and tripods are all going to need to be obtained separately unless you already have a reliable support system from a conventional astronomical rig on which you can put these OTAs. The good news is that they’ll accept any standard 2" eyepiece that you already have.
Lunt also offers a larger 102mm version, but with fewer options: just the scope, or the scope with different blocking filters; and an even bigger 152mm monster, also just different blocking filters—all with a single pressure-tuned etalon. As with the 60mm’s previously discussed, you’re just getting the OTA—eyepieces, mount, and tripod are all required for proper use.
Not a company to disappoint its customers, B&H has thoughtfully put together kits for you that include Lunt’s 50mm LS50THa OTA with an iOpton CubePro GoTo mount and tripod. All you need are eyepieces. As with the first White Light recommendation, this mount can be used with conventional OTAs for nighttime use, so it’s a great option for those who have a sincere interest in all types of celestial observations. Again, for those who already have a mount and tripod, you have the option of getting just the OTA.
Last up, and representing the pinnacle of dedicated solar scopes, is the line of SoliRedi OTAs from Daystar Filters. Utilizing the company’s electronic temperature-tuning system, these come pre-calibrated for specific bandpasses within the H-alpha wavelength with appropriate blocking filters. Starting with a 0.4Å (Angstrom) version that specifically improves solar surface contrast and fine chromosphere details, as well as to study the photosheric, chromospheric, prominence, and atmospheric areas of the sun generally; you have options increasing in 0.1Å-intervals, up to 0.7Å. At this bandpass, it reveals prominences in high contrast; and under the right conditions, surface texture. Through a 0.7 filter, prominences appear larger than when viewed with narrower bandwidth filters. These four options allow users to concentrate on very specific regions of the sun to make incredibly detailed observations. Continuing a trend, these OTAs are special order only and are offered with just the OTAs, so eyepieces, mount, and tripod are up to you to provide.
Daystar also offers a bit of a hybrid that doesn’t really fall into any category: the 480E 80mm Refractor. This is a conventional nighttime OTA that comes bundled with the company’s Quark filter. The Quark functions like the etalon previously mentioned, in that it uses an electronic temperature tuner, but instead of being integrated into the optical tube, it is an accessory that can be used with any OTA. It simply installs between the focuser (or diagonal), and the eyepiece goes into the Quark. Daystar offers three versions of this—an Ha Quark for Chromosphere viewing, another for Prominence viewing, or a Sodium (Na) D-line quark for viewing a completely different wavelength (again, check out the Solar and Eclipse Viewing 101 article for what Na D-line viewing reveals).
Conclusion
Whether you want to spend $100, $10,000, or anything in between, there will be a dedicated solar scope to fit your needs, wants, and budget. Regardless of what you go with, make sure you grab a pair of solar glasses and read what comes with your selection—you’re often going to need something simple, like eyepieces, or maybe you’ll take the opportunity to upgrade your mount and tripod and go with a kit. Conversely, if you’re an experienced nighttime astronomer and have eyepieces, mount, and tripod that you love, then go for the OTA-only options.
No matter what you decide, I recommend going out and testing the gear you get well in advance of the eclipse so you’re well versed in setting up, aligning, and finding the sun before this once-in-a-lifetime event comes and goes while you’re still trying to get it in your field of view.
Now go grab some gear and (safely) look at the sun—you know you’ve always wanted to.
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