William Optics AP 108/518 Apochromatic Refractor UltraCat WIFD

Clear, flat and razor sharp - in one shot
The William Optics AP 108/518 UltraCat is made for those who want to take their astrophotos to the next level.
You get a clear image across the entire frame, with no distortion at the edges. Thanks to the Petzval design, you don't need a separate flattener. So you shoot beautiful photos faster, easier and more consistently.

Large aperture for sharp deep-sky images
With its 108 mm aperture, this refractor captures a lot of light. That means short exposure times and sharp details even in faint nebulae or star fields. The f/4.8 brightness makes the telescope ideal for wide sky shots and large deep-sky objects.

Stable focusing, even with heavy cameras
The internal WIFD focuser sits completely inside the tube. So your camera always stays nice and straight, without tilting or sagging. You fine tune, your stars stay round, and your framing stays just the way you want it.
The focuser is compatible with electronic focus motors, allowing you to focus automatically and super-precise.

Cleverly designed for real photographers
You get a built-in rotator for perfect framing. Rotate your camera without disturbing the entire setup.
The tilt lens helps prevent sensor tilt, keeping your stars nice and sharp at every angle.
Even the Bahtinov mask is incorporated into the dew cap. You snap it off, focus, and you're good to go.

Built to stay reliable
The lens cells are temperature-stable, so your optics will stay sharp in colder or warmer weather. The aluminum tube feels sturdy and remains low-vibration.
With the included handle, mount accessories safely and stably - ideal for a guidescope.

Specifications

Optics

Focuser

Mount

Included accessories

General