Recently Browsing 0 members
No registered users viewing this page.
Hi,currently owned 70mm refractor, want to upgrade and many suggested me to get 6" dobsonian.
The only 6" dob i can find in my country is GSO 150mm/1200mm dob (https://www.opticaluniversescientificinstrument.com/products/gso-6-dobsonian-telescope), is this brand and specs ok?
My main targets is planet and moon, maybe some star, i wonder is it hard to imaging planets? ill be using ccd eyepiece connected to laptop.
I live in malaysia city area, very less likely i will bring the scope to darker area because its pretty far from my home,and the scope quite big, so its dobsonian suitable for minor light population?
I heard that that dobsonian can affected by weather and cooling the scope be a big issue?
hope expert can give some advice. thanks
Just wondering what peoples thoughts are on the pro's and con's of the different types of mounts out there? Do Dobsonian mounts have issues on non-flat surfaces (like a garden) or can Equatorial mounts ever have issues getting out of line too easily?
Very happy with it! Wish the sky were clear, but as we all know, when we buy astro equipment, it's cloudy! Argh!
The telescope was collected from David Lukehurst at noon and then we travelled back to Cambridge.
John Nichol primary mirror: 37mm thickness, Suprax. Hilux coated. Optics 1/8 PV wavefront 1/27 wave RMS. Strehl .95. Secondary mirror: 62mm MA.
Here a few photos:
I am thinking on grinding my own lightweight mirror (first f4 16", later f4 24"). The lightest and cheapest option is to get a thin blank and slump it in a decent kiln.
Anyone has longer term experiene with slumped mirrors? Overall doesn't seem to be more work than a normal (not pregenerated) blank.
Do I have to grind the backside as in case of normal flat back mirrors to avoid astigmatism? How do people support a convex back while grinding? Does it make sense to grind a hole in the middle for additional support? I am remotely considering a convertible Newtonian/Cassegrain system anyway...
Looking for a 12" DOB (or larger) which can be transported to Prestwick, Ayrshire. Any brand, as long as the telescope is optically sound and in good working order. I'm a reliable buyer who has bought and sold on this site before.