Sky Rover 0.8x Specialist Reducer for 155GPS Telescope
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Sky Rover Optics 0.8x Specialist Reducer for 155GPS
The Sky Rover 0.8x Specialist Reducer for the 155GPS telescope is a purpose-engineered optical accessory that converts the native system from 1240mm f/8 down to a faster 992mm f/6.4. By integrating precision focal reduction with advanced field flattening, it expands your field of view by roughly 64% and slashes exposure times by more than a third while keeping stars pinpoint and round across full-frame sensors. Please note: Telescope is not included with 0.8x reducer.
When used with the 155GPS telescope, the effective focal length changes from 1240mm to 992mm, and the focal ratio changes from F/8 to F/6.4, allowing for full-frame imaging with an excellent image circle of 45mm.
Configured as shipped from the factory, this reducer has a standard back focus of 55mm.
- Note: To meet full-frame light path requirements, the rear end of this reducer uses an M54x0.75 male thread. If a longer back focus is required, please strictly follow the structural and installation instructions.
When using a DSLR: if a multi-step adapter such adapter such as M54-M48-T2 is used, the back focus may exceed the allowable range, resulting in suboptimal imaging. In this case, it is recommended to use a direct M54-T2 adapter. For mirrorless cameras, you may use either the M54-T2 adapter or the M54-M48 camera adapter. Always pay attention to the back focus when installing.
Adjust Back Focus
During imaging, if notice any of the following issues with the star points, the back focus may need adjustment.
The product comes with multiple adjustment spacers. Based on the actual imaging results - especially the qualith of star points at the edges of the frame - you can add or remove spacer to adjust the back focus and improve image quality.
Pre-installed Spacers
At the factory, a total of 0.7mm of PVC spacers (0.2mm + 0.5mm) have already been pre-installed.
The package includes two 0.5mm PVC spacers and one 0.2mm PVC spacer for further adjustment.
The position for installing the adjustment spacers is shown in the diagram below.
Specification
-
Model: 0.8x Specialist Reducer for 155GPS
-
Optical: 3 elements in 3 groups, including ED glass
-
Compatibility: Specifically designed for the SKY ROVER 155GPS Telescope
-
Image Circle: 55mm Full Frame
-
Thread Interfaces:
-
Objective Lens Side: M92
-
Camera Side: M92x1 / M54×0.75
-
-
Back Focus Distance: 55mm (measured from the M54 surface)
-
Dimensions: 78mmx116mm
-
Front & Rear Caps: Aluminum alloy
Spot Diagram
Accessory Diagram
- When installing the reducer, first unscrew the 2.5" adapter on the telescope counterclockwise.
- DSLR mount, cooled camera adapters, DSLR cameras, cooled cameras, OAG and filter wheels are not included and must be purchased separately.
- Three PVC spacers (0.5mm + 0.5mm + 0.2m) are included, which can be added as needed for back focus adjustment.
Camera Connection Diagram
①Telescope ②3.7" Interface ③0.8x specialist reducer ④DSLR Mount ⑤Cooled Camera Adapter ⑥DSLR Camera ⑦Cooled Camera
Spacer Connection Diagram
①Telescope ②3.7" Interface ③0.8x specialist reducer ④Spacer ⑤Rear Interface
Back Focus Diagram
Other Information
- Country of Manufacture: China
Sky Rover Optics 0.8x Specialist Reducer for 155GPS
The Sky Rover 0.8x Specialist Reducer for the 155GPS telescope is a purpose-engineered optical accessory that converts the native system from 1240mm f/8 down to a faster 992mm f/6.4. By integrating precision focal reduction with advanced field flattening, it expands your field of view by roughly 64% and slashes exposure times by more than a third while keeping stars pinpoint and round across full-frame sensors. Please note: Telescope is not included with 0.8x reducer.
When used with the 155GPS telescope, the effective focal length changes from 1240mm to 992mm, and the focal ratio changes from F/8 to F/6.4, allowing for full-frame imaging with an excellent image circle of 45mm.
Configured as shipped from the factory, this reducer has a standard back focus of 55mm.
- Note: To meet full-frame light path requirements, the rear end of this reducer uses an M54x0.75 male thread. If a longer back focus is required, please strictly follow the structural and installation instructions.
When using a DSLR: if a multi-step adapter such adapter such as M54-M48-T2 is used, the back focus may exceed the allowable range, resulting in suboptimal imaging. In this case, it is recommended to use a direct M54-T2 adapter. For mirrorless cameras, you may use either the M54-T2 adapter or the M54-M48 camera adapter. Always pay attention to the back focus when installing.
Adjust Back Focus
During imaging, if notice any of the following issues with the star points, the back focus may need adjustment.
The product comes with multiple adjustment spacers. Based on the actual imaging results - especially the qualith of star points at the edges of the frame - you can add or remove spacer to adjust the back focus and improve image quality.
Pre-installed Spacers
At the factory, a total of 0.7mm of PVC spacers (0.2mm + 0.5mm) have already been pre-installed.
The package includes two 0.5mm PVC spacers and one 0.2mm PVC spacer for further adjustment.
The position for installing the adjustment spacers is shown in the diagram below.
Specification
-
Model: 0.8x Specialist Reducer for 155GPS
-
Optical: 3 elements in 3 groups, including ED glass
-
Compatibility: Specifically designed for the SKY ROVER 155GPS Telescope
-
Image Circle: 55mm Full Frame
-
Thread Interfaces:
-
Objective Lens Side: M92
-
Camera Side: M92x1 / M54×0.75
-
-
Back Focus Distance: 55mm (measured from the M54 surface)
-
Dimensions: 78mmx116mm
-
Front & Rear Caps: Aluminum alloy
Spot Diagram
Accessory Diagram
- When installing the reducer, first unscrew the 2.5" adapter on the telescope counterclockwise.
- DSLR mount, cooled camera adapters, DSLR cameras, cooled cameras, OAG and filter wheels are not included and must be purchased separately.
- Three PVC spacers (0.5mm + 0.5mm + 0.2m) are included, which can be added as needed for back focus adjustment.
Camera Connection Diagram
①Telescope ②3.7" Interface ③0.8x specialist reducer ④DSLR Mount ⑤Cooled Camera Adapter ⑥DSLR Camera ⑦Cooled Camera
Spacer Connection Diagram
①Telescope ②3.7" Interface ③0.8x specialist reducer ④Spacer ⑤Rear Interface
Back Focus Diagram
- 1x 0.8x Reducer
- 2x 0.5mm spacers
- 1x 0.2mm spacer
Sky Rover Optics 0.8x Specialist Reducer for 155GPS
The Sky Rover 0.8x Specialist Reducer for the 155GPS telescope is a purpose-engineered optical accessory that converts the native system from 1240mm f/8 down to a faster 992mm f/6.4. By integrating precision focal reduction with advanced field flattening, it expands your field of view by roughly 64% and slashes exposure times by more than a third while keeping stars pinpoint and round across full-frame sensors. Please note: Telescope is not included with 0.8x reducer.
When used with the 155GPS telescope, the effective focal length changes from 1240mm to 992mm, and the focal ratio changes from F/8 to F/6.4, allowing for full-frame imaging with an excellent image circle of 45mm.
Configured as shipped from the factory, this reducer has a standard back focus of 55mm.
- Note: To meet full-frame light path requirements, the rear end of this reducer uses an M54x0.75 male thread. If a longer back focus is required, please strictly follow the structural and installation instructions.
When using a DSLR: if a multi-step adapter such adapter such as M54-M48-T2 is used, the back focus may exceed the allowable range, resulting in suboptimal imaging. In this case, it is recommended to use a direct M54-T2 adapter. For mirrorless cameras, you may use either the M54-T2 adapter or the M54-M48 camera adapter. Always pay attention to the back focus when installing.
Adjust Back Focus
During imaging, if notice any of the following issues with the star points, the back focus may need adjustment.
The product comes with multiple adjustment spacers. Based on the actual imaging results - especially the qualith of star points at the edges of the frame - you can add or remove spacer to adjust the back focus and improve image quality.
Pre-installed Spacers
At the factory, a total of 0.7mm of PVC spacers (0.2mm + 0.5mm) have already been pre-installed.
The package includes two 0.5mm PVC spacers and one 0.2mm PVC spacer for further adjustment.
The position for installing the adjustment spacers is shown in the diagram below.
Specification
-
Model: 0.8x Specialist Reducer for 155GPS
-
Optical: 3 elements in 3 groups, including ED glass
-
Compatibility: Specifically designed for the SKY ROVER 155GPS Telescope
-
Image Circle: 55mm Full Frame
-
Thread Interfaces:
-
Objective Lens Side: M92
-
Camera Side: M92x1 / M54×0.75
-
-
Back Focus Distance: 55mm (measured from the M54 surface)
-
Dimensions: 78mmx116mm
-
Front & Rear Caps: Aluminum alloy
Spot Diagram
Accessory Diagram
- When installing the reducer, first unscrew the 2.5" adapter on the telescope counterclockwise.
- DSLR mount, cooled camera adapters, DSLR cameras, cooled cameras, OAG and filter wheels are not included and must be purchased separately.
- Three PVC spacers (0.5mm + 0.5mm + 0.2m) are included, which can be added as needed for back focus adjustment.
Camera Connection Diagram
①Telescope ②3.7" Interface ③0.8x specialist reducer ④DSLR Mount ⑤Cooled Camera Adapter ⑥DSLR Camera ⑦Cooled Camera
Spacer Connection Diagram
①Telescope ②3.7" Interface ③0.8x specialist reducer ④Spacer ⑤Rear Interface
Back Focus Diagram
Other Information
- Country of Manufacture: China
- 1x 0.8x Reducer
- 2x 0.5mm spacers
- 1x 0.2mm spacer
Sky Rover 0.8x Specialist Reducer for 155GPS Telescope