William Optics RedCat 51 WIFD

Name: William Optics RedCat 51 WIFD
Brand: William Optics

Recommended

William Optics

William Optics RedCat 51 WIFD is a 51 mm Petzval APO refractor for wide-field nebulae, large targets, and travel-friendly imaging.

telescope $$$ Deep sky Travel kit Wide-field nebulae

Best Current Offer

Agena AstroProducts

In stock

$888.00

Other retailers

Cloud Break Optics (In stock)
$888.00
High Point Scientific (In stock)
$888.00
Mile High Astronomy (In stock)
$888.00

Specifications

Optics

Optical design: Petzval APO refractor
Aperture: 51 mm
Focal length: 250 mm
Focal ratio: f/4.9
Dawes limit: 2.27"
Glass / elements: 4-element Petzval

Imaging

Image circle: 48 mm
Camera format: Full frame / APS-C / Micro 4/3
Full-frame coverage: Yes
Back focus: No flattener required
Corrected field: Flat full-frame field

Mechanical

Focuser: WIFD rack-and-pinion internal focuser
Weight: 1.77 kg / 3.9 lb
Tube length: 298 mm
Dovetail: Vixen / Arca-Swiss dual plate

Astrophotography Fit

Best for wide-field nebulae, large targets, and travel-friendly imaging when the mount, camera format, and correction hardware are chosen as one system.

William Optics RedCat 51 WIFD sits in the telescope slot for wide-field nebulae, large targets, and travel-friendly imaging. The useful headline specs are aperture 51 mm, focal length 250 mm, f/4.9.

Camera coverage: Full frame / APS-C / Micro 4/3. Image circle: 48 mm. Back focus: No flattener required.

Fast astrographs collect signal quickly, but they are unforgiving: collimation, tilt, filter behavior, and back-focus spacing show up immediately in star shapes.

Weight matters here: 1.77 kg / 3.9 lb. Leave payload headroom for the camera, guider, focuser, dew control, and cables instead of judging the mount by bare tube weight alone.

Best paired with

Rigid focuser, tilt adjuster, and exact corrector spacing
Cooled cameras with a sensor inside the corrected image circle
High-throughput filters that behave well at fast focal ratios

Not recommended for

Users who do not want to tune collimation, tilt, and spacing
Thick or narrow filters that show strong bandpass shift at fast focal ratios
Loose camera adapters or focusers that cannot hold the imaging train square

Where To Buy

Some links on this page are affiliate links. Prices and availability are pulled automatically from each retailer and updated daily.

Retailer	Price	Availability	View Offer
Agena AstroProducts Agena AstroProducts	$888.00	In stock Updated 8/4/2026	View Offer - $888.00
Cloud Break Optics Cloud Break Optics	$888.00	In stock Updated 8/4/2026	View Offer - $888.00
High Point Scientific High Point Scientific	$888.00	In stock Updated 8/4/2026	View Offer - $888.00
Mile High Astronomy Mile High Astronomy	$888.00	In stock Updated 8/5/2026	View Offer - $888.00

Price History

Chronological retailer pricing with out-of-stock points shown at reduced opacity.

Agena AstroProducts Cloud Break Optics High Point Scientific Mile High Astronomy