William Optics FLAT GT Full Frame 1x Flattener for GT-71/81 Telescopes

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- This item is out of stock.
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- This item is out of stock.
- We have no ETA from the manufacturer at this time.
- Sign up for back-in-stock alerts to be notified when this item becomes available.
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William Optics FLAT GT Full Frame 1x Flattener for GT-71/81 Telescopes # P-FLAT-GT
Notes:
- GT71 Telescope: The P-FLAT-GT will work with the GT71 without any additional adapters. Using the 1.6mm threaded spacer, the back focus is 56.6mm.
- GT81 IV Telescope (non-WIFD): An M63-M63 extension tube is now included with the P-FLAT-GT. This needs to be inserted between the telescope and the flattener. When the GT81 IV is used with the P-FLAT-GT and this extension tube, the back focus is 55mm (remove the 1.6mm threaded spacer).
- GT81 IV Telescope (WIFD version): The P-FLAT-GT can also be used with the latest GT81 WIFD, but requires the additional purchase of the adapter (P-M92EX). This is not included with the flattener; you can see this in the 'Related Products' section above this description. For the GT81 WIFD + Adapter, the back focus is 55mm (remove the 1.6mm threaded spacer).
Specifications
- Lens Type: 1 Group 2 Elements
- Length: 22 mm
- Telescope Thread: M63 x 1 x 6 mm
- T-mount Thread: M48 x 0.75 x 4 mm
- T-mounts Supported:
- Canon EF, RF
- Nikon F, Z
- Sony E
- Pentax K
- MFT (M4/3)
- FUJI X
- Camera Format: > Full Frame
- Weight: 179.7 g / 396.17 lbs
- Gran Turismo 71
- Back Focus: 56.6mm
- Adjustment Distance: 1.6mm (Using Threaded Spacer)
- Image Circle: ∅ 44mm
- Gran Turismo 81
- Back Focus: 55mm
- Adjustment Distance: No Need to Adjust (Remove the Threaded Spacer); However, you need to add the M63 spacer between the telescope and the flattener. This spacer is now included with this flattener.
- Image Circle: ∅44mm
- Gran Turismo 81 WIFD + Front Adapter ( # P-M92EX )
- Back Focus: 55mm
- Adjustment Distance: No Need to Adjust (Remove the Threaded Spacer). Requires # P-M92EX adapter, sold separately.
- Image Circle: ∅44mm
Other Information
- Country of Manufacture: Taiwan
William Optics FLAT GT Full Frame 1x Flattener for GT-71/81 Telescopes # P-FLAT-GT
Notes:
- GT71 Telescope: The P-FLAT-GT will work with the GT71 without any additional adapters. Using the 1.6mm threaded spacer, the back focus is 56.6mm.
- GT81 IV Telescope (non-WIFD): An M63-M63 extension tube is now included with the P-FLAT-GT. This needs to be inserted between the telescope and the flattener. When the GT81 IV is used with the P-FLAT-GT and this extension tube, the back focus is 55mm (remove the 1.6mm threaded spacer).
- GT81 IV Telescope (WIFD version): The P-FLAT-GT can also be used with the latest GT81 WIFD, but requires the additional purchase of the adapter (P-M92EX). This is not included with the flattener; you can see this in the 'Related Products' section above this description. For the GT81 WIFD + Adapter, the back focus is 55mm (remove the 1.6mm threaded spacer).
Specifications
- Lens Type: 1 Group 2 Elements
- Length: 22 mm
- Telescope Thread: M63 x 1 x 6 mm
- T-mount Thread: M48 x 0.75 x 4 mm
- T-mounts Supported:
- Canon EF, RF
- Nikon F, Z
- Sony E
- Pentax K
- MFT (M4/3)
- FUJI X
- Camera Format: > Full Frame
- Weight: 179.7 g / 396.17 lbs
- Gran Turismo 71
- Back Focus: 56.6mm
- Adjustment Distance: 1.6mm (Using Threaded Spacer)
- Image Circle: ∅ 44mm
- Gran Turismo 81
- Back Focus: 55mm
- Adjustment Distance: No Need to Adjust (Remove the Threaded Spacer); However, you need to add the M63 spacer between the telescope and the flattener. This spacer is now included with this flattener.
- Image Circle: ∅44mm
- Gran Turismo 81 WIFD + Front Adapter ( # P-M92EX )
- Back Focus: 55mm
- Adjustment Distance: No Need to Adjust (Remove the Threaded Spacer). Requires # P-M92EX adapter, sold separately.
- Image Circle: ∅44mm
William Optics FLAT GT Full Frame 1x Flattener for GT-71/81 Telescopes # P-FLAT-GT
Notes:
- GT71 Telescope: The P-FLAT-GT will work with the GT71 without any additional adapters. Using the 1.6mm threaded spacer, the back focus is 56.6mm.
- GT81 IV Telescope (non-WIFD): An M63-M63 extension tube is now included with the P-FLAT-GT. This needs to be inserted between the telescope and the flattener. When the GT81 IV is used with the P-FLAT-GT and this extension tube, the back focus is 55mm (remove the 1.6mm threaded spacer).
- GT81 IV Telescope (WIFD version): The P-FLAT-GT can also be used with the latest GT81 WIFD, but requires the additional purchase of the adapter (P-M92EX). This is not included with the flattener; you can see this in the 'Related Products' section above this description. For the GT81 WIFD + Adapter, the back focus is 55mm (remove the 1.6mm threaded spacer).
Specifications
- Lens Type: 1 Group 2 Elements
- Length: 22 mm
- Telescope Thread: M63 x 1 x 6 mm
- T-mount Thread: M48 x 0.75 x 4 mm
- T-mounts Supported:
- Canon EF, RF
- Nikon F, Z
- Sony E
- Pentax K
- MFT (M4/3)
- FUJI X
- Camera Format: > Full Frame
- Weight: 179.7 g / 396.17 lbs
- Gran Turismo 71
- Back Focus: 56.6mm
- Adjustment Distance: 1.6mm (Using Threaded Spacer)
- Image Circle: ∅ 44mm
- Gran Turismo 81
- Back Focus: 55mm
- Adjustment Distance: No Need to Adjust (Remove the Threaded Spacer); However, you need to add the M63 spacer between the telescope and the flattener. This spacer is now included with this flattener.
- Image Circle: ∅44mm
- Gran Turismo 81 WIFD + Front Adapter ( # P-M92EX )
- Back Focus: 55mm
- Adjustment Distance: No Need to Adjust (Remove the Threaded Spacer). Requires # P-M92EX adapter, sold separately.
- Image Circle: ∅44mm
Other Information
- Country of Manufacture: Taiwan
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