ZWO 30F5 30mm f/5 ED APO Mini Guide Scope

A small ED APO guide scope that locks its focus and stays put

The ZWO 30F5 Mini Guide Scope is a 30mm f/5 ED apochromatic guide scope with a 150mm focal length. It carries a guide camera on top of your imaging telescope so your mount can correct its tracking during long exposures. It replaces ZWO's earlier 30F4, adding a third lens element with ED glass, a longer focal length for finer guiding, and a lockable non-rotating helical focuser in place of the old threaded front focuser.

Key specs: 30mm aperture · 150mm focal length, f/5 · 3-element APO with ED glass · 20mm focus travel with locking screws · 1.25" (31.8mm) camera holder and M42 x 0.75 thread · Synta/Vixen-style finder foot · 155mm long · 348g

What it does for your images

• Round stars in long exposures: paired with a guide camera and the ASIAIR or PHD2, it lets you expose for minutes instead of seconds.
• Dithering and polar alignment: the guide camera in the 30F5 also handles dithering between frames and the ASIAIR's polar alignment routine.
• Finer guiding than a 120mm scope: at 150mm it gives a smaller image scale than most short guide scopes, so the guider sees smaller tracking errors.
• More than guiding: ZWO also shows it with a planetary camera threaded onto the M42 rear for wide-field snapshots, and with a 1.25" eyepiece as a straight-through finder (a 25mm eyepiece gives 6x).

How to set it up

Slide the 30F5's foot into a finder shoe on your telescope or camera rig and tighten the shoe's screw. Slide a ZWO Mini guide camera into the rear 1.25" holder until the red-black edge on the camera lines up with the end of the holder, then loosen the locking screws, turn the red focuser ring until stars are sharp, and lock it again. The focuser doesn't rotate the camera as you turn it, so your framing stays put. ZWO's focus example shows the focuser position for a ZWO Mini camera and for cameras with 12.5mm and 17.5mm back focus, with a focus tolerance of ±1.5mm.

No finder shoe on your rig? The ZWO Finder Base FS-II screws onto an ASIAIR Plus or a ZWO camera holder ring and gives the 30F5 a place to sit.

Which guide camera to use

Here's what each ZWO Mini guide camera sees through the 30F5's 150mm 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 ASI2600MC Pro (3.76µm pixels), that's about 3.1"/px on a 250mm RedCat 51 and about 1.6"/px on a 490mm ZWO FF70, both comfortable matches for the 30F5 with an ASI220MM Mini.

What to add for the best results

• ZWO ASI220MM Mini (or another 1.25" guide camera, required): the guide scope needs a camera to see through.
• ZWO ASIAIR Plus 256GB: runs guiding, your main camera and the mount from your phone.
• ZWO Finder Base FS-II: a finder shoe for mounting the 30F5 on an ASIAIR Plus or a ZWO holder ring.
• ZWO Large OAG: the better choice than any guide scope for SCTs and telescopes over about 750mm.

30F5 vs. other guide scopes

See all autoguiding gear and ZWO accessories.

What's in the box

• ZWO 30F5 guide scope with built-in finder-shoe foot
• Two M4 x 8mm thumbscrews
• One M3 x 6mm brass screw

The guide camera and finder shoe are sold separately.

ZWO 30F5 Mini Guide Scope FAQ

Is it good for beginners?

Yes. It's one of the simplest guide scopes to set up: slide in the camera, focus once, lock it, and you're done. Paired with an ASIAIR, guiding is a few taps.

Which guide camera should I pair with it?

The ASI220MM Mini is the one we suggest most. The ASI120MM Mini works well on a budget, and the ASI174MM Mini fits too, though it really shines in an off-axis guider.

30F5 or 30F4?

The 30F4 is discontinued and the 30F5 replaces it. The 30F5 adds an ED apochromatic third element, a longer 150mm focal length for finer guiding (good for main scopes up to about 750mm instead of 600mm), and a non-rotating helical focuser with locking screws.

Will it fit my telescope?

Its foot fits a standard Synta/Vixen-style finder shoe, found on most refractors. If your rig doesn't have one, the ZWO Finder Base FS-II mounts on an ASIAIR Plus or a ZWO holder ring.

Can I use it with an SCT?

For a long SCT, we recommend an off-axis guider instead, such as the ZWO Large OAG with an ASI174MM Mini. A 150mm guide scope is too coarse and can flex relative to a 1500mm to 2000mm main telescope.

Can I use it as a finderscope?

Yes. With a 1.25" eyepiece in the rear holder it works as a straight-through finder: a 25mm eyepiece gives 6x.

Specifications