William Optics is used to churning out excellent telescopes regularly, but they are especially stoked about their latest product. The WO-Star71 imaging telescope provides pinpoint stars at the very edge of a 45mm imaging circle. Take a look at a new production sample photo of the Heart Nebula (IC 1805) / h Persei (NGC 869) / Chi Persei (NGC 884) area in Perseus taken with this telescope!
- 71mm f/4.9 Imaging Refractor Telescope
- FPL-53 ED glass element for color free apochromatic performance
- 5 elements in 3 groups (3-1-1- configuration; see photo 2 above. New, unique, patented design - not a conventional objective/flattener/reducer design)
- Covers 45mm full frame imaging circle
- 2.5" dual speed R&P focuser
- Includes mounting rings and Vixen style dovetail
- Weight = 4.5 lbs / 2.05 kg (OTA only); 5.3 lbs / 2.4 kg (OTA with rings and dovetail)
- Focuser drawtube travel = 1.38" / 35mm
- Back focus = 66.4mm from 48mm Canon thread and 91.4mm from drawtube end
- Optional deluxe soft-padded carry case available separately
- Focuser drawtube terminates in a male M48x0.75 thread. Telescope comes with a wide M48-Canon EOS adapter ring. Similar rings are available from other supplier for other brands of cameras. Not a conventional 2" focuser tube with locking thumbscrews.
- Optional 1.25" 90-deg dielectric mirror diagonal sold separately for those wishing to use this as a visual scope (see "Related Products" tab above). This diagonal comes with a custom adapter that connects directly to the M63 female thread on the telescope's focuser tube; you cannot use standard 1.25" diagonals. Telescope cannot reach focus with larger 2" diagonals.
- The first production run of this telescope had an M65 female thread which was later replaced with a more common M63 thread in subsequent production runs.
Specification for ED Lenses
All William Optics refractor objectives are double tested and inspected by WO at their factory. These telescopes are free of coma and astigmatism. Since all individual lens surfaces are machine coated, sometimes you may notice visual imperfections which will not compromise the optical performance of the telescope. THe dimensions of scratches and points shall not exceed the following values:
- Scratches - Maximum Width: 0.025 mm
- Scratches - Maximum Length: 1/4 of total lens diameter
- Scratches - Maximum Quantity: Three
- Dots or Spot Points - Maximum Diameter: 0.4 mm
- Dots or Spot Points - Maximum Quantity: Three
- Accumulation of Defects - Limited Area: 0.8mm^2
- Accumulation of Defects - Total Area: 5.8mm^2