Addendum - Astro Hardware |
Ronchi Eypieces |
updated: 2024-04-12 |
Ronchi eyepiece - evaluate the optical quality of your telescope with a star
By means of easily to interprete stripe patterns, you can see how good your telescope is.
- High quality grating in 1.25" nose piece
- On a plano-parallel glass substrate, 10 lines per mm are etched in. This leads to a high testing precision.
- Easily interpretable - if the stripes are straight and parallel, everything is okay (see picture on the left)
- By interpreting deviations, the optical errors can be determined
- Also ideal to find the focal plane
- Helps also to correct the mirror distance as in RC-Telescopes:
|
Spherical Overcorrection |
Perfect Optics |
Spherical Undercorrection |
|||
|
Intrafocal |
Extrafocal |
Intrafocal |
Extrafocal |
Intrafocal |
Extrafocal |
|
|
|
|
|||
|
Mirrors are too close together Parabolic mirrors may have a slight spherical Overcorrection, as many coma correctors introduce spherical Undercorrection. Both errors might erase each other out. |
Mirror distance is good |
Mirrors are too far apart Same as in Spherical Overcorrection but with changed prefix! Lots of fast optics for astrophotography show a slight spherical abberation. Due to the scale of the images that doesn't matter too much. (You're far away from the theoretical limits of your optics!) Lot's of coma correctors introduce some spherical undercorrection. |
|||
See also: Correcting the mirror distance
Documentation: ronchi-manual.pdf (teleskop-express.de)
Suppliers: Teleskop Express
Ronchi Eyepiece (Gerd Neumann)
Price: ~ 50 EUR
Created with the Personal Edition of HelpNDoc: Elevate Your CHM Help Files with HelpNDoc's Advanced Customization Options