Founder Optics 2” Field Flattener for f/5 - f/7 Refractor Telescopes (with M42 T/T2 Thread and M48 Adapter)
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- Founder Optics 2” field flattener for refractors of focal ratio f/5 to f/7
- Flattens image field for cameras with APS-C or smaller sensors
- 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
- Requires 55mm back focus
The Founder Optics 1.0x field flattener # FLAT1.0 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.
This flattener includes interchangeable M42x0.75 male and M48x0.75 male thread adapters to interface with your camera T-ring (not included). This 2” flattener delivers an image circle of 44mm, large enough for use with full-frame cameras when used with the M48 adapter. If used with the M42 adapter, note that your image circle will be reduced to 38mm so this should only be used with APS-C and smaller sensor cameras.
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.
The Founder Optics 2” field flattener requires a standard back focus of 55mm. This makes it ideal for DSLR cameras with a standard M42 or M48 T-ring (sold separately). It also works with most other astronomy cameras when matched with suitable extension rings (sold separately).
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 Founder Optics 1.0x field flattener # FLAT1.0 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.
This flattener includes interchangeable M42x0.75 male and M48x0.75 male thread adapters to interface with your camera T-ring (not included). This 2” flattener delivers an image circle of 44mm, large enough for use with full-frame cameras when used with the M48 adapter. If used with the M42 adapter, note that your image circle will be reduced to 38mm so this should only be used with APS-C and smaller sensor cameras.
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.
The Founder Optics 2” field flattener requires a standard back focus of 55mm. This makes it ideal for DSLR cameras with a standard M42 or M48 T-ring (sold separately). It also works with most other astronomy cameras when matched with suitable extension rings (sold separately).
The flattener features fully multi-coated optics in an anodized CNC-machined aluminum body with a polished gloss black finish.
- Founder Optics 2” field flattener for refractors of focal ratio f/5 to f/7
- Flattens image field for cameras with APS-C or smaller sensors
- 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
- Requires 55mm back focus
The Founder Optics 1.0x field flattener # FLAT1.0 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.
This flattener includes interchangeable M42x0.75 male and M48x0.75 male thread adapters to interface with your camera T-ring (not included). This 2” flattener delivers an image circle of 44mm, large enough for use with full-frame cameras when used with the M48 adapter. If used with the M42 adapter, note that your image circle will be reduced to 38mm so this should only be used with APS-C and smaller sensor cameras.
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.
The Founder Optics 2” field flattener requires a standard back focus of 55mm. This makes it ideal for DSLR cameras with a standard M42 or M48 T-ring (sold separately). It also works with most other astronomy cameras when matched with suitable extension rings (sold separately).
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
Founder Optics 2” Field Flattener for f/5 - f/7 Refractor Telescopes (with M42 T/T2 Thread and M48 Adapter)