Orion Starmax/Apex line and baffling

I have an Orion Apex 90 and adjusting the Moon or Jupiter just out of the FOV I see huge amount of reflection. I feel this is the lack of adequate baffling, so my question is that can I eliminate somehow this problem? Also, have you experienced such annoying reflection with the big brother (Apex/Starmax 127) of this telescope?

As regards the optics it is almost as sharp as an ETX90, so in this respect it is good.

Thanks for your comments,
Levente

Hello, Levente.

I recommend a simple meniscus shield/baffle sleeve (like a dew shield on a refractor). Cardboard, craft foam, felt-lined bubble-wrap -- these materials are fine. Make sure the interior of the shield is flat black (not glossy or shiny or otherwise reflective). The sleeve/shield should project a distance equivalent to at least 1.5x the scope's aperture (up to 2x is also fine -- do not make it much longer). This would mean about 5 to 7 inches for your Apex 90.

All cassegrain designs require some level of compromise with regard to the length and/or shape of the primary baffle tube. If a primary baffle tube is made long enough to strictly/fully baffle the meniscus, then it will end up projecting into the primary light cone, thus *increasing* the effective diameter of the central obstruction. On the other hand, if a baffle tube is made short enough to allow for *zero* additional obstruction, then the meniscus ends up *not* being fully baffled.

A forward shield/sleeve/extension baffle should help quite a bit.

Best wishes.
-Dan