Stray light suppression in a Newtonian with anti-reflective paint or

In Newtonian telescopes, the internal blackening is often insufficient, so stray light reduces contrast. This can be easily achieved by painting with a special anti-reflective paint or lining with velour film (e.g., DC-Fix). Blackboard paint has a lower anti-reflective effect.

The advantage of anti-reflective paint is its easy application with a paint roller. We first heat the tube with a hot air gun and apply three to four coats of paint. Applying the velour film is considerably more complex, as it needs to be applied without bubbles and must be cut to size.

The blackening result is comparable for both versions, with a slight bias in favor of the velour film.

See also: http://www.teleskop-spezialisten.de/shop/Dienstleistung-Service:::10.html