Sky-Watcher EvoGuide 50ED Flattener

Sky-Watcher Field Flattener for EvoGuide 50DX – Bring Sharpness to the Corners

If you're using the Sky-Watcher EvoGuide 50DX as a wide-field astrograph, the dedicated Field Flattener is a must-have accessory. This simple yet essential optical corrector transforms your compact ED refractor into a fully capable imaging telescope, delivering pinpoint stars from edge to edge—even on larger camera sensors.

Why You Need a Field Flattener

Refractors—especially fast, short focal length models like the EvoGuide 50DX—are known for producing a curved field. While the center of your image may be razor-sharp, the edges can appear soft or stretched when paired with modern DSLR, mirrorless, or cooled CMOS cameras. This is especially noticeable with APS-C and full-frame sensors.

That’s where the field flattener comes in. It’s designed specifically for the EvoGuide 50DX’s optical system to correct this curvature and expand the usable field of view. With the flattener in place, you get a flat, distortion-free field that maintains stellar sharpness across the entire frame—no cropping required.

Optimized for Astrophotography

This field flattener provides a 1.0x magnification, meaning it won’t alter the focal length of the EvoGuide 50DX. You'll still enjoy the same fast f/4.8 imaging speed and wide field, but now with improved performance across the sensor.

It’s engineered to deliver optimal correction at the standard 55mm backfocus, making it a seamless match for most DSLR and mirrorless camera setups using a T-ring. For dedicated astro cameras, the backfocus spacing remains just as easy to manage with standard spacers or adapters.

Threaded for Easy Integration

Sky-Watcher designed the flattener with versatility in mind. The rear threads are standard M48, allowing for wide T-ring connections that reduce vignetting—particularly important if you’re using a full-frame sensor. The front threads attach directly to the EvoGuide 50DX focuser, providing a secure, threaded connection that keeps your optical train aligned and stable throughout long exposures.

No wobble, no sag—just a tight, solid fit for better imaging consistency.

Compact, Lightweight, and Purpose-Built

Just like the EvoGuide itself, the flattener is compact and lightweight, so it won’t upset your mount’s balance or overtax a portable tracking rig. It’s designed exclusively for the EvoGuide 50DX, ensuring the optical spacing and correction are precisely dialed in—something you won’t get from a generic flattener.

If you’re using the EvoGuide 50DX for imaging and haven’t added the field flattener yet, you’re leaving performance on the table. Whether you’re shooting large nebulae or rich star fields, this accessory helps you get the most out of your scope and your camera.

Highlights:

• Flattens the field of the EvoGuide 50DX for sharp stars across the frame

• 1.0x design preserves original focal length and fast f/4.8 speed

• Ideal for APS-C and full-frame sensors

• M48 threads for wide, secure camera connections

• 55mm backfocus spacing for easy DSLR and astro cam compatibility

• Purpose-built for the EvoGuide 50DX—perfect fit and optical match

This isn't just an upgrade—it's the final piece that turns your EvoGuide 50DX into a true wide-field astrograph. Whether you're a beginner wanting better stars or an advanced imager fine-tuning your setup, the Sky-Watcher Field Flattener makes a visible difference where it counts.