Glossary | Telescopes | General | Series | SolarMax II

The SolarMax II telescopes for observing the Sun in H-alpha light are among the best-selling solar telescopes for experienced observers.

They include a high-quality etalon from Coronado which filters out the H-alpha solar hydrogen line. In the light of the excited hydrogen atom the Sun’s chromosphere becomes visible and there is always something to see: filaments, flares and other phenomena on the solar disc, and prominences on the Sun's surface.

SolarMax II telescopes include the patented Conorado RichView system, with which the etalon filter can be very easily and precisely adjusted. For an image with even more contrast, the SolarMax II can also be equipped with a second etalon.

The SolarMax II is supplied with tube clamps, a solar finder, an eyepiece and a carrying case.

Many solar telescopes are also available with a Double Stack. This means that two Etalon filters are installed, one behind the other. This reduces FWHM of the transmitted H-alpha line light to less than 0.5 Angstroms. Without a double stack, the FWHM is below 0.7 angstroms.

The smaller FWHM means noticeably higher contrast. The structures on the sun appear three-dimensional. The narrower FWHM of the filter also means the image is darker and requires fine readjustment using with the systems tuning system.

The deflection optics with the eyepiece receiver also accommodate the blocking filter. This filter reduces the brightness of the solar image and is therefore a very important part of the solar telescope, and which must under no circumstances be removed!

The number after the BF in the product name indicates the diameter of the blocking filter in millimetres. For example, BF10 means that the blocking filter is 10 millimeters in diameter. For purely visual observing, a small blocking filter is sufficient, but for photography a larger one should be selected.

Locating the Sun with a telescope is more complicated than you would think, and is often the source of an involuntary and unprotected glance at the Sun!

The Sol Ranger finder scope is a special solar finder with a ground glass screen. So you can align your telescope easily, safely and quickly.

The H-alpha filter is a so-called etalon. In the etalon, the majority of the light in the visible spectral region is removed by the destructive interference of the incident light. Only the desired wavelength of 656 nanometres gets through.

In order to achieve this, the width of the etalon must be set precisely and adjusted during observation. The RichView tuning system makes this adjustment especially easy!