Long Perng 2” Adjustable Field Flattener for f/5 - f/7 Refractor Telescopes (with 55-80mm Back Focus & M42 T/T2 Thread)
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- Long Perng 2” adjustable field flattener for refractors of focal ratio f/5 to f/7
- Ohara glass elements deliver flatter, bright images across the field for cameras with up to full-frame sensors
- Adjustable back focus from 55mm to 80mm
- Integrated T/T2 M42 thread for camera attachment (an M48 version of this reducer is also available separately)
- CNC machined body with hard, gloss, black anodized finish
- Features 2" nosepiece with safety groove
The Long-Perng adjustable field flattener # K1.0Z-AU minimizes field curvature caused by the objective lenses of fast refractors and provides a sharper image across the camera sensor.
As a 1.0x flattener, it does not change the effective focal length of the telescope. The optical design of this flattener makes it optimal for use with refractors with a focal ratio of approximately f/5 to f/7 when used with an APS-C sensor. With smaller sensor 1” and 4/3” cameras, it can work well with refractors slightly outside this range of focal ratio.
With standard male M42x0.75 T/T2 threads to interface with the camera, this 2” reducer/flattener provides a clear aperture of 38mm which is suitable for use with cameras with APS-C sensors and smaller. An M48-threaded version of this item with a larger clear aperture is also sold separately.
The flattener’s nosepiece slides into any standard 2” telescope focuser. Note: The nosepiece has a female M48x0.6 thread on the telescope side and will only accept Orion 2” filters - it will NOT accept most other 2” filters on the market which use the more common M48x0.75 threads.
By twisting the housing of this flattener, the lens-to-camera sensor spacing can be adjusted from 55-80mm to accommodate a wide range of CCD, CMOS and DSLR cameras without the need for separate spacer or extension rings. Once the back focus is set, a rigid locking mechanism ensures zero flexure without slippage for stable imaging performance.
The flattener features fully multi-coated optics in an anodized CNC-machined aluminum body with a polished gloss black finish.
Other Information
- Country of Manufacture: Taiwan
The Long-Perng adjustable field flattener # K1.0Z-AU minimizes field curvature caused by the objective lenses of fast refractors and provides a sharper image across the camera sensor.
As a 1.0x flattener, it does not change the effective focal length of the telescope. The optical design of this flattener makes it optimal for use with refractors with a focal ratio of approximately f/5 to f/7 when used with an APS-C sensor. With smaller sensor 1” and 4/3” cameras, it can work well with refractors slightly outside this range of focal ratio.
With standard male M42x0.75 T/T2 threads to interface with the camera, this 2” reducer/flattener provides a clear aperture of 38mm which is suitable for use with cameras with APS-C sensors and smaller. An M48-threaded version of this item with a larger clear aperture is also sold separately.
The flattener’s nosepiece slides into any standard 2” telescope focuser. Note: The nosepiece has a female M48x0.6 thread on the telescope side and will only accept Orion 2” filters - it will NOT accept most other 2” filters on the market which use the more common M48x0.75 threads.
By twisting the housing of this flattener, the lens-to-camera sensor spacing can be adjusted from 55-80mm to accommodate a wide range of CCD, CMOS and DSLR cameras without the need for separate spacer or extension rings. Once the back focus is set, a rigid locking mechanism ensures zero flexure without slippage for stable imaging performance.
The flattener features fully multi-coated optics in an anodized CNC-machined aluminum body with a polished gloss black finish.
- Long Perng 2” adjustable field flattener for refractors of focal ratio f/5 to f/7
- Ohara glass elements deliver flatter, bright images across the field for cameras with up to full-frame sensors
- Adjustable back focus from 55mm to 80mm
- Integrated T/T2 M42 thread for camera attachment (an M48 version of this reducer is also available separately)
- CNC machined body with hard, gloss, black anodized finish
- Features 2" nosepiece with safety groove
The Long-Perng adjustable field flattener # K1.0Z-AU minimizes field curvature caused by the objective lenses of fast refractors and provides a sharper image across the camera sensor.
As a 1.0x flattener, it does not change the effective focal length of the telescope. The optical design of this flattener makes it optimal for use with refractors with a focal ratio of approximately f/5 to f/7 when used with an APS-C sensor. With smaller sensor 1” and 4/3” cameras, it can work well with refractors slightly outside this range of focal ratio.
With standard male M42x0.75 T/T2 threads to interface with the camera, this 2” reducer/flattener provides a clear aperture of 38mm which is suitable for use with cameras with APS-C sensors and smaller. An M48-threaded version of this item with a larger clear aperture is also sold separately.
The flattener’s nosepiece slides into any standard 2” telescope focuser. Note: The nosepiece has a female M48x0.6 thread on the telescope side and will only accept Orion 2” filters - it will NOT accept most other 2” filters on the market which use the more common M48x0.75 threads.
By twisting the housing of this flattener, the lens-to-camera sensor spacing can be adjusted from 55-80mm to accommodate a wide range of CCD, CMOS and DSLR cameras without the need for separate spacer or extension rings. Once the back focus is set, a rigid locking mechanism ensures zero flexure without slippage for stable imaging performance.
The flattener features fully multi-coated optics in an anodized CNC-machined aluminum body with a polished gloss black finish.
Other Information
- Country of Manufacture: Taiwan
Long Perng 2” Adjustable Field Flattener for f/5 - f/7 Refractor Telescopes (with 55-80mm Back Focus & M42 T/T2 Thread)