Takahashi TOA-150B Double ED Triplet Refractor Telescope - Heavy-Duty 4" Focuser

The Takahashi TOA-150B employs a newly designed triplet using special elements to produce the highest order of color correction. Orthoscopic means perfected visually and Apochromatic means you're free from those strange violet glows which often accompany bright stars or planets. Thanks to the ingenious design of layering an FPL-53 Extra-low Dispersion glass element between two extreme quality crown and flint elements - perfection ensues. And what's more, it's air spaced, so there's no oil between the elements to leak or become opaque with age. The lens cells are durably constructed to withstand transport - yet are fully able to be collimated should the owner wish to make adjustments. With 1/12th wave accuracy and an airy-disc Strehl ratio of 0.992, the optics on the Takahashi TOA-150B Ortho-APO are as near to perfection as you can get! The Takahashi TOA-150B Ortho-APO is a dream come true for those who want to use a medium format camera. It includes a newly designed 4" focuser that use