Askar 52mm Super ED Guide Scope (249.6mm f/4.8, Black or Silver)

Finer guiding for longer telescopes, and a sharp little finder too

The Askar 52mm Super ED Guide Scope is a 52mm f/4.8 doublet with one SD element and a 249.6mm focal length. It rides on a finder base on your imaging telescope and feeds a guide camera, so your mount can correct its tracking during long exposures. An integrated helical focuser with 25mm of travel, X-Y alignment adjustment, and a set of removable adapters and extension tubes let you set it up for a guide camera, a planetary camera or an eyepiece. It's CNC-machined and anodized, in black or silver to match your telescope.

Key specs: 52mm aperture · 249.6mm focal length, f/4.8 · doublet with 1 SD element · integrated helical focuser, 25mm travel · 1.25" adapter, M42 × 0.75 adapter and two 40mm extension tubes · finder-base foot with 1/4-20 and M4 holes, X-Y adjustment · 255mm long · 740g

What you can do with it

• Guide a longer refractor: round stars in multi-minute exposures on telescopes in the 500mm to 1,000mm range, plus dithering between frames and the ASIAIR's polar alignment routine.
• Use it as a finder: with a 1.25" diagonal and a 25mm eyepiece it shows 10x and about a 6° field, and a 9mm eyepiece gives about 28x for a quick look at the Moon or a bright cluster.
• Grab wide snapshots: thread a small planetary camera onto the M42 adapter for quick wide-field shots; an ASI585MC frames about 2.6° × 1.4°, enough for the Pleiades or the Double Cluster.

How to set it up

Guiding: slide the foot into a finder base and tighten it, or bolt it on with the 1/4-20 or M4 hole. Put a 1.25" guide camera in the rear 1.25" adapter with the extension tubes in place, focus with the helical focuser, then use the X-Y screws to line it up with your main telescope.

Threaded cameras: for a planetary or deep-sky camera, swap the 1.25" adapter for the M42 × 0.75 adapter. Different cameras put the sensor at different distances, so add or remove the 40mm extension tubes until you reach focus.

Visual: remove the extension tubes and attach the 1.25" adapter, then add a 1.25" diagonal and eyepiece.

Which guide camera to use

Here's what each ZWO Mini guide camera sees through the 52mm's 249.6mm focal length:

As a rule of thumb, guiding stays accurate when the guide camera's image scale is within about five times your imaging scale. With an APS-C camera such as the ASI2600MC Pro, the 52mm with an ASI220MM Mini covers telescopes up to about 1,000mm, including the SQA130 (624mm), 111F (766mm) and 131F (983mm).

Fits / works with

• Askar refractors with finder bases: the SQA106 and SQA130 (on the handle or beside the focuser), the 91F, 111F and 131F.
• Any other telescope with a standard finder base, or a rail with a 1/4-20 or M4 screw.

What to add for the best results

• A guide camera (required for guiding): the ZWO ASI220MM Mini, ASI120MM Mini or ASI174MM Mini.
• A controller: the ZWO ASIAIR Plus runs guiding, your main camera and the mount from your phone.
• For visual use: a Celestron 1.25" star diagonal and a 25mm X-Cel LX eyepiece (10x).
• For small astrographs: the lighter Askar 32mm f/4 guide scope.

52mm Super ED vs. 32mm f/4

See all autoguiding gear and Askar telescopes and accessories.

What's in the box

• Askar 52mm Super ED guide scope with finder-base foot, in black or silver
• 1.25" adapter
• M42 × 0.75 threaded adapter
• Two 40mm extension tubes
• Manual

The guide camera, diagonal and eyepieces are sold separately.

Askar 52mm Super ED FAQ

Is 52mm too big for a guide scope?

Not on a telescope of 500mm or more, where its longer focal length pays off. On a small astrograph under about 500mm, the lighter 32mm f/4 guides just as well.

Guide scope or off-axis guider?

A guide scope is simpler to set up and finds guide stars easily. An off-axis guider such as the ZWO OAG-L avoids any flexure between two telescopes, which matters most on long focal lengths and SCTs.

Can I use it as a finder scope?

Yes. Remove the extension tubes, attach the 1.25" adapter and add a diagonal and eyepiece. A 25mm eyepiece gives 10x.

Will it fit my telescope?

If your telescope has a standard finder base, yes. The foot also has 1/4-20 and M4 threaded holes for bolting it to a rail or bracket.

Specifications