As a high-powered stargazing tool, this 0.77 Reducer / Flattener from Sky-Watcher is a must-have for astrophotographers utilising the Esprit-150ED Professional Super APO Triplet Refractor OTA. In short, the field flattener accurately corrects the inherent spherical aberration of curved lenses. Without such a tool, image quality is lessened as the frame appears distorted at the edges of the field of view. When used as a focal reducer, you are afforded a key reduction in the focal ratio of the scope. By doing so, you are left with a wider field of view with shortened exposure time, allowing for more images to be captured in a shorter amount of time without affecting their overall quality.
Sky-Watcher 0.77 Reducer / Flattener for Esprit-150ED Key Features:
- Solely compatible with the Esprit-150ED Professional Super APO Triplet Refractor OTA
- Specifically suited to astrophotographers and astroimaging
- Promises to essentially eliminate spherical aberrations
- Actively shortens the focal ratio from f7 to f5.4
- 68% reduction in exposure time
- Compatible with APS-C and full frame cameras
- Full frame camera produces 2.54 x 1.7° field of view
- APS-C crop sensor produces 1.66 x 1.11° field of view
- Consists of a sizeable 36mm imaging circle
- Produces a fully illuminated
- 90mm or 55mm back-focus (with back focus spacer and M48 ring)
- Implements a 2” filter thread
- Suited to a vast array of filters such as moon, polarizing, and light pollution
What’s in the box?
- 1 x Sky-Watcher 0.77 Reducer / Flattener for Esprit-150ED
- 1 x Back Focus Spacer
- 1 x M48 Thread Adapter
- 2 x Threaded Cap
- Limited 2-Year Warranty
Does the Sky-Watcher 0.77 Reducer / Flattener come equipped with end caps?
This astrophotography tool does come equipped with green anodised aluminium screw-on end caps.
How many optical elements are implemented within the design?
The 0.77 Reducer / Flattener utilises three key optical elements within its internal design.
How heavy is this device?
The Sky-Watcher 0.77 Reducer / Flattener weighs 910g with threaded caps attached.
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||Focal Reducer/Field Flattener