Expand your field! Reduce your f/value, speeding up the collection of photons! And do it with pin-point stars all the way to the corners of your full frame 35 mm sensor!
Four carefully matched glass elements are carefully figured and then coated with the very latest multi-coatings to produce this optical wonder. All mechanical parts, including the covers, are CNC machined and black anodized with a lustrous finish.
The male threads are 3.270" x 16
Backfocus Spacing
Scope | Part Code | Backfocus Spacer | Spacing with Bf. S. | Spacing without Bf. S. |
AP 130 GTX | QUADTCC-AP130 | 22.1 mm | 80.8 mm | 102.9 mm |
TEC 140 | QUADTCC-TEC140 | 18.3 mm | 80.8 mm | 99.1 mm |
TEC 160 | QUADTCC-TEC160 | 17.0 mm | 80.8 mm | 97.8 mm |
TEC 180 | QUADTCC-TEC180 | 16.0 mm | 80.8 mm | 96.8 mm |
Important Note: When purchasing the QuadTCC the proper length Backfocus Spacer is included for the scope specified. However, when ordering the QuadTCC for a TEC scope you will also need to order a Drawtube Endcap (S35RFAA) for the focuser (see part listing below). This only applies to the TEC focusers. This part is integral to the Astro-Physics 3.5" focusers and is not needed as a separate purchase. The S35RFAA screws onto the drawtube's 4.100" x 24 thread (same as Starlight Instrument's 3.5" focuser endcap thread).
Backfocus Spacers to Use with Other Scopes that you Own
If you have multiple scopes from the list above and wish to purchase a Backfocus Spacer separately in order to use the QuadTCC on the different scopes, below are the spacers listed by length (reference the table above) and corresponding part number. | ||
Backfocus Spacer Length | Part Number | ![]() |
22.1 mm | A5020 | |
18.3 mm | A2680 | |
17.0 mm | A5022 | |
16.0 mm | A5023 |
Optical Spacer Rings (Part #A5025SET)
In most imaging setups it will not be necessary to modify the spacing distance. However, there may be some sensor/camera combinations that can benefit by making slight changes to this spacing.
A set of three 1 mm thick spacer rings is being offered that can be used in special circumstances to modify the backfocus spacing of the Telecompressor Corrector.
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