TPO 2" 0.75x Focal Reducer for RC Telescopes

TPO 2" 0.75x Focal Reducer for RC Telescopes
Item # OS-FRRC-75
7 Questions(s)

Waiting List

  • Third Planet Optics 0.75x reducer will shorten your exposure times.
  • Fully-multi coated optics.
  • 2" slip fit adapter makes it easily attached to the TPO RC telescopes and your other 2" accessories.
  • Most compatible with CCD sensors with a 15mm or smaller diagonal measurement.
  • Enough back focus to include an off-axis guider and filter wheel in your imaging set up.


Fully multi-coated optics, the Third Planet Optics 2" focal reducer will reduce your focal length by 0.75x shortening exposure times while still retaining a crisp image with excellent color and contrast. Extra long focal length to be perfectly compatible with the TPO RC telescopes, off-axis guiders and filter wheels and is best for CCD sensors with up to a 15mm diagonal. Two element design effectively reduces focal ratios of the Third Planet Optics Ritchie Chretien from f/9 to f/6.75 and from f/8 to f/6.
Additional Information

Additional Information

Manufacturer TPO
Barrel Size 2"
Warranty 1 Year Warranty
Questions & Answers

Product Questions

How would this work on my Meade ACF 16? And with a canon 6D DSLR?
Compatible with TPO RC6 + DLRS Canon EOS 60D?
What is the correct spacing for this focal reducer? I just bought one and I have no idea how to configure my CCD camera and accessories.
Will the Flattener/reducer work with the 10"RC and my SBIG STF8300C?
I have an 8 inch RC and a SBIG8300 that is 22.5mm diagonal measure. Also a CFW and OAG. Beyond 15 mm is the problem vignetting or are there significant aberrations too? How bad are the aberrations if any?
I have an Orion 8 f/8 Ritchey-Chretien Astrograph Telescope and currently using Atik filterwheel + atik 383L+ camera with a sensor size of 17.6mm x 13.52mm: Will it work properly ? How much will it increase the speed of my scope ?
Thank you in advance
What is the correct spacing for this focal reducer if I us a HuTech Flattener?
Support / Downloads