Askar 32mm f/4 Guide Scope (128mm, Black or Silver)

A 303g guide scope that disappears on top of a small astrograph

The Askar 32mm f/4 Guide Scope is a compact doublet with a 128mm focal length. It rides on top of your imaging telescope and feeds a guide camera, so your mount can correct its tracking during long exposures. It comes in black or silver to match your telescope, and it's the guide scope we pair with Askar's smaller astrographs, from the 50P to the SQA85.

Key specs: 32mm aperture · 128mm focal length, f/4 · doublet objective · integrated helical focuser, 20mm travel · 1.25" adapter and M42 × 0.75 adapter · finder-base foot with X-Y adjustment · 137mm long · 303g

What it does for your images

• Round stars in long exposures: with a guide camera and an ASIAIR or PHD2, you can expose for minutes instead of seconds.
• Dithering: guiding lets your controller shift the frame slightly between exposures, which cleans up noise patterns when you stack.
• Polar alignment help: the ASIAIR can use the guide camera for its polar alignment routine.

How to set it up

Slide the foot into a finder base on your telescope's handle or focuser and tighten the thumbscrew. Put a 1.25" guide camera in the rear adapter, or remove the adapter and thread an M42 camera straight on. Aim at a bright star, turn the focuser until the star is smallest, and use the X-Y adjustment screws to center the same star you see in your main camera. Once it's set, you can usually leave it alone from night to night.

Which guide camera to use

Here's what each ZWO Mini guide camera sees through the 32mm's 128mm 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, that covers telescopes up to about 600mm, such as the SQA85 (408mm) or 91F (609mm), with an ASI220MM Mini.

Fits / works with

• Askar telescopes with a finder base: the 50P (on its handle), FMA180 Pro (on top), SQA60 Pro, SQA70 and SQA85 (beside the focuser), the 60F, 71F and 91F, and the N160.
• SQA55: add the SQA55 quick-release handle bar, which has a finder base on top.
• Any other telescope or rig with a standard finder base. The ZWO Finder Base FS-II adds one to an ASIAIR Plus or ZWO camera holder ring.

What to add for the best results

• A guide camera (required): the ZWO ASI220MM Mini or the budget ASI120MM Mini.
• A controller: the ZWO ASIAIR Plus runs guiding, your main camera and the mount from your phone.
• For longer telescopes: the Askar 52mm Super ED guide scope or a ZWO OAG off-axis guider.

32mm f/4 vs. 52mm Super ED

See all autoguiding gear and Askar telescopes and accessories.

What's in the box

• Askar 32mm f/4 guide scope with finder-base foot, in black or silver
• 1.25" adapter
• M42 × 0.75 threaded adapter

The guide camera and controller are sold separately.

Askar 32mm Guide Scope FAQ

Do I need a guide scope?

Not for short exposures on a star tracker. Once you want exposures longer than a minute or so, or want to dither between frames, guiding makes a clear difference in star shapes.

32mm or 52mm?

The 32mm is lighter and plenty for telescopes up to about 600mm. The 52mm Super ED has twice the focal length for finer guiding on longer telescopes and gathers more light for fainter guide stars.

Will it fit my telescope?

If your telescope has a standard finder base (the dovetail shoe most finders slide into), yes. Most Askar telescopes have one on the handle or beside the focuser.

Can I use a camera with a threaded nose?

Yes. Remove the 1.25" adapter and thread an M42 × 0.75 camera onto the rear.

Specifications