The Sky Rover 72 GPA is the sweet spot for portable imaging — 432mm at f/6, Super ED glass, and a tube light enough to balance on a star tracker. Point it at a wide star field or a large nebula and the view at the eyepiece is gorgeous. But attach a camera, and the doublet's inherent field curvature becomes visible: stars in the center are tight and round, while stars at the edges of the sensor start to elongate. That's the physics of a fast doublet, not a flaw — and it's exactly what the SR72GPAFF 1× field flattener is designed to correct.
The flattener maintains the 72 GPA's native 432mm focal length and f/6 ratio. It changes nothing about the focal length or speed — it simply flattens the curved focal plane into a flat one that matches your camera sensor. The result is sharp, round stars from center to corners. For a scope this size and weight, adding a matched flattener transforms it from a capable visual instrument into a complete deep-sky imaging platform.
Flattener, Not Reducer
This is a 1× flattener — it preserves the native focal length and focal ratio of the 72 GPA. If you want the full 432mm f/6 with a corrected field, this is the accessory. The field of view, the star size, and the exposure times all remain the same as the uncorrected scope — you just get flat, well-corrected stars across the sensor instead of curved, elongated ones at the edges.
Camera Connection
The camera side of the flattener connects to your imaging equipment via standard threads. DSLR and mirrorless cameras connect via a T-ring for your specific camera mount (sold separately). Dedicated CMOS and CCD astronomy cameras typically have 48mm T-threads built in and connect directly without a T-ring.
What's Included
- Sky Rover SR72GPAFF 1× field flattener for 72 GPA
Features
-
1× field flattener — no focal reduction. Maintains the 72 GPA's native 432mm f/6. Corrects field curvature for flat, sharp stars across the sensor without changing the imaging characteristics.
-
Dedicated design for the Sky Rover 72 GPA. Matched to the 72 GPA's optical prescription. Not a generic universal flattener — purpose-designed for this scope's specific field curvature profile.
-
Transforms the 72 GPA into a complete imaging platform. The 72 GPA's compact size and light weight make it ideal for travel and star trackers. Adding the matched flattener gives you a flat-field imaging system at 432mm f/6 that fits in a camera bag and balances on a tracker.
-
Standard camera-side threading. DSLR and mirrorless bodies connect via a T-ring (sold separately); dedicated CMOS/CCD astronomy cameras attach directly — 48mm T-threads are standard on most.
Frequently Asked Questions
Do I need this flattener for visual observing?
No. Field curvature only affects imaging — your eye naturally accommodates the curved focal plane during visual observation. The flattener is specifically for camera work.
Will this fit any other Sky Rover scope?
No. The SR72GPAFF is designed specifically for the 72 GPA's optical prescription and mechanical connection. Using it on a different scope will not produce correct results. Each Sky Rover scope has its own matched flattener.
What cameras does this work with?
DSLR and mirrorless cameras connect via a T-ring for your specific camera mount (sold separately). Dedicated CMOS and CCD astronomy cameras typically have 48mm T-threads built in and connect directly without a T-ring.
Is there a reducer available for the 72 GPA instead?
Sky Rover does not currently list a reducer for the 72 GPA on the accessory sheet. The 1× flattener is the dedicated corrector for this scope. If a faster system is your priority, consider the 72 GPA at its native f/6 — it's already quite fast for a doublet refractor.
Final Thoughts
If you own the 72 GPA and you're imaging — or plan to image — the SR72GPAFF is the accessory that makes it work. The scope is already one of the lightest, most portable Super ED doublets available. Adding the matched flattener gives you flat, corrected stars at the native 432mm f/6 without adding meaningful weight or complexity. It turns a great grab-and-go visual scope into a great grab-and-go imaging scope. That's all it needs to do, and it does it.
