6-inch doublet lens
Aperture is king, they say, and at six inches in diameter the Evostar 150ED DS-Pro likely presents the maximum manageable size of refractor for many amateurs. The doublet lens is multicoated and displays a purplish hue. Photographic tests showed no sign of unwanted reflections or artefacts, and visual star tests demonstrate that the lens cell holds the glass without evidence of skewing or pinching, even through temperature drops of over 10°C. The large aperture makes finding fainter objects easier, and even with moonlit skies and moderate light pollution we could observe both major sections of the Veil Nebula complex with our OIII filter and 21mm eyepiece. Meanwhile, planetary nebulae such as M57 and M27 stood out really well from the background sky. Globular and open clusters were sharp and clear, and bright star Vega showed only the faintest trace of false colour as the seeing varied. Lunar views during steady seeing showed good detail in crater walls and we easily picked out the main craterlets within the crater Plato.