[Nikolas (Nik)]

Originally Posted by mura_gadi

Hello,


Thanks for the link and thanks to Alex for the article.


But there are never any holes in the tube or fans on the side of the tube above the mirror to remove the thermal currents early. They are allowed to travel up the tube to exit. Pretty sure it would be easy to design a breather/extractor hole to allow hot air from the mirror to exit without allowing light in closer to the mirror cell.



thanks
Steve

Making the hole light proof adds to the cost of the scope, even SCT's have vent holes behind the mirror.