When I was director of the East Kentucky Science Center in Prestonsburg, Kentucky, we created an outreach program with a mobile observatory. Because the program went to schools in the daytime, we needed solar scopes.
So I visited Coronado Telescopes in Tucson, Arizona. At the time, it made the best small solar telescopes available. When I entered the workshops, I was immediately struck by the people and products I encountered. The attention to detail, craftsmanship, and precision were obviously paramount.
The solar scopes I purchased for the Science Center performed flawlessly. Needless to say, that meant I was excited to receive the new 70mm SolarMax III telescope to inspect, use, and review.
Out of the box
Those of us who own quality equipment know the importance of good storage. The SolarMax III case is made of aluminum with metal reinforcing bands across all the edges, and additional reinforcement on each corner. The aluminum panels on the case are anodized black, while all the reinforcing bands are finished in brass. This carrying case looks like a piece of luxury luggage; it was certainly built to protect the telescope inside.
Opening the case reveals the SolarMax telescope nestled in the fitted interior foam. The finish on the scope is a combination of brass and black anodization. It looks great and reminds me of a fine 19th-century instrument.
SolarMax III is, in fact, a 2.75-inch (70 millimeters) f/5.7 refracting telescope with a 400mm focal length. The actual solar filters are mounted on front of the tube assembly, making this an incredibly versatile telescope — but more about that later. As with all solar scopes, SolarMax III lets you directly and safely observe the Sun’s chromosphere in real time. Unlike common full-aperture, white-light solar filters, which allow you to safely view a combination of all of the Sun’s visible light, the SolarMax III provides views of our daytime star specifically in the Hydrogen-alpha (Hα) wavelength.
Meade produces the SolarMax with either a single and double stack of filters; this refers to the number of etalon filters supplied on the instrument. (Etalon is a French word for “standard.”) These filters were developed over a hundred years ago and remain the standard for this type of equipment. The review telescope has a double-stack configuration, which gives finer control of tuning and, thus, reveals more detail.
The Sun produces energy all across the electromagnetic spectrum. It’s like the Sun’s total energy output being all the keys on a piano played at once. Hα, then, is just a single key. Wavelengths are measured in angstroms or nanometers. That of Hα is at 6562.8 A or 656.28 nm. Etalon filters are designed to eliminate all but this single line of energy.