Jump to content

Banner.jpg.32030495336bee81a52546621b6f39a2.jpg

Tunnel vision


Recommended Posts

I've done the collimation in my house, sort of larger than a small flat, almost the other end of focus travel with a normal EP.  Your long tunnel might need a flat of Football field size, and you might need to drill a hole in upstair neighbor's floor to see the light in tunnel:icon_biggrin:

  • Like 1
Link to comment
Share on other sites

To artificially star test you need a really long base line otherwise you can introduce spherical aberration into the test as the wavefronts entering the telescope will still be spherical rather than plane wave.  This can either make you think the scope is no good, or potentially cancel out an inherent problem hiding an issue that is present.  Once you the artificial star is sufficient distance away that problem will fall below your detection limit and the waves will essentially be plane.

  • Like 2
Link to comment
Share on other sites

As Matthew has said, don't confuse collimating with testing for optical quality, the latter requires a very distant light source or an optical test bench generated infinity for indoor use.

  • Like 1
Link to comment
Share on other sites

21 minutes ago, DirkSteele said:

To artificially star test you need a really long base line otherwise you can introduce spherical aberration into the test as the wavefronts entering the telescope will still be spherical rather than plane wave.  This can either make you think the scope is no good, or potentially cancel out an inherent problem hiding an issue that is present.  Once you the artificial star is sufficient distance away that problem will fall below your detection limit and the waves will essentially be plane.

Thanks - I won't be trying this indoor again....

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.