My first Magazine Sky & Telescope - 03.2019

of the Sun. The prominence versions (SS60P and SS80P) use a wider 0.8- to 0.6-angstrom bandpass, which displays prominences a bit brighter than the chromosphere model does, though at the expense of other details across the Sun’s disk. I tested the SS60C. The Solar Scout is a nearly complete observing kit that incorporates a remov- able Quark ﬁ lter — a Fabry-Pérot etalon Hα ﬁ lter that was reviewed in the November 2014 issue, p. 38. The scope comes with a waterproof, foam-lined hard case, a solar “bullet” ﬁ nder, an AC-to-DC power supply, and a mount- ing foot threaded for ¼-20 standard tripods that also doubles as a short Vixen-style dovetail plate. Optics in the SS60C are an f/3.75 doublet objective in a carbon-ﬁ ber OTA, which, when combined with an integral Barlow lens within the Quark ﬁ lter, extends the effective focal length of the system to approximately 930- mm (f/15.5) in a 16-inch-long pack- age. Users will need to provide a star diagonal and eyepiece. The scope’s focus travel is sufﬁ cient to accommodate most standard 1¼-inch diagonals com- bined with a range of eyepieces. One useful aspect of the SS60C is that its Quark ﬁ lter is removable (an option not available on the SS60-ds), and, with the addition of an optional adapter and appropriate energy-rejec- tion ﬁ lter, it can be used safely on other refractors. This is particularly helpful for users hoping to image the Sun, as I’ll explain later. The Quark is a temperature-regu- lated Hα solar etalon that’s powered by a supplied wall transformer with a gen- erous 9½-foot cable, which plugs into a USB-micro port on the side of the ﬁ lter. Plug adapters are included for other types of international wall outlets. This power heats the Quark’s etalon cavity to between 100° and 150°F, precisely regulating the ﬁ lter’s passband. As an electrically stabilized ﬁ lter, the Quark needs to be powered up for about 10 minutes before an observing session begins in order for its tempera- ture to stabilize. An LED located near the power port changes from yellow to green when it’s ready. The LED is tiny but bright enough to be seen in full sunlight. While it isn’t dangerous to view through the ﬁ lter while it is reach- ing operating temperature, the views are extremely low-contrast and off- band before stabilizing, appearing like a white-light view, except colored red. The power transformer provides 5 VDC at 2 amps. The Quark can also be powered with most DC power supplies that have a USB output, though you’ll need to ensure the power supply can output 2 amps. An included 14-page manual is extremely helpful and directly answered any questions I had whether I was using the instrument visually or with an imaging setup. changing one click-stop, but contrast improved slightly when moving several stops at a time. The manual states that turning the knob clockwise increases (redshifts) the center wavelength of the ﬁ lter, while counter-clockwise decreases (blueshifts) its central passband. This is useful when looking at prominences along the limb, which can sometimes be blue- or red-shifted, revealing details that were fainter or even invisible before changing the ﬁ lters’ tuning. Unlike a white-light view of the Sun, observing in the dimmer, deep-red Hα Under the Sun Although the ﬁ ltering system that iso- lates the Hα band does permit viewing and imaging of solar features, the qual- ity of the view with the SS60C depends on several factors. The seeing or steadiness of our atmosphere is one big consideration. Daytime seeing is generally much worse than nighttime and can blur ﬁ ne detail associated with active solar regions. Local conditions signiﬁ cantly help or worsen the quality of the image viewed through any solar telescope. My best seeing almost always came in the early morning hours, even though the Sun was lower in the sky than when at its midday position. I experienced slightly better seeing when I used the SS60C outside on my lawn, rather than attach- ing the scope piggyback on my observa- tory telescope in its domed building. Users can loosen a thumbscrew on top of the scope to allow the ﬁ lter to be rotated to place the power input and tuning knob in a convenient position. The tuning knob has 5 click-stops on either side of a center position, with each click changing the transmitted wavelength by 0.1 Å. When adjust- ing the knob, even slightly, the LED changes from green back to yellow. It takes several minutes to stabilize and turn green again after each adjustment. I couldn’t see much difference when pp Placing the Sun in the telescope’s fi eld of view is easy using the bullet fi nder. Focus- ing the SS60C is accomplished by turning the large, red anodized collar. p The SS60C’s peak passband can be adjust- ed +/- 0.5 angstroms in 0.1-Å increments using the tuning knob. While most features across the solar disk looked best at the mid-position, prominences sometimes changed appearance when turning the knob 2 or 3 clicks. It took several minutes for the fi lter to stabilize each time the knob was adjusted. sk yandtele scope.com • M A RCH 2 019 59

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