Explore Scientific Twilight I 18 lb Alt-Azimuth Mount with Tripod

Product Overview

The Twilight I is Explore Scientific's adjustable-angle alt-azimuth mount and tripod, rated for a telescope weight of 18 pounds. The head is powder-coated aluminium, 14″ x 7″ x 4″, running worm gears on both axes with slow-motion control cables and oversized knurled knobs. The legs are stainless steel with a spreader bar, and the tripod opens to a 42″ footprint.

Explore Scientific publishes the head at 6.6 lb (3.0 kg), the tripod base at 11 lb (5.0 kg) and the assembled mount at 16.7 lb (7.6 kg). Height is adjustable across a wide range: with the head fitted and the legs retracted the highest point is 38.5″, with 36″ to the centre of the mounting bracket; with the legs fully extended those figures become 55.5″ and 53″.

The head tilts through an adjustable 45-degree angle. That is the feature that separates it from a plain alt-azimuth head: tipping the azimuth axis lets a straight-through refractor reach the zenith without the eyepiece ending up under the tripod.

Who It's For

• Refractor owners up to 18 pounds: the published telescope capacity covers most short and medium refractors along with their diagonal, finder and a heavy eyepiece.
• Observers who want to be looking through the telescope within a minute of arriving: there is no polar alignment, no power and no initialisation — the mount points where you push it.
• Anyone observing near the zenith with a straight-through tube: this is a good match if you have found yourself lying on the ground to reach the eyepiece on a conventional alt-azimuth head. The 45-degree adjustable tilt exists for exactly that.
• Observers who use gloves: the oversized knurled knobs on the slow-motion cables were sized with cold hands in mind.
• Outreach and travel use, where the 42″ collapsed-with-head length and 16.7 lb total are easier to move than an equatorial head plus counterweights.

Key Features & Design

• 18 pound published telescope capacity, which is the figure to measure your loaded tube against.
• Worm gears on both axes: a worm drive gives fine, backlash-controlled motion that a friction head cannot, and it holds position when you let go.
• Adjustable 45-degree tilt on the head, so a straight-through refractor can reach high altitudes with the eyepiece in a workable place.
• Slow-motion control cables with oversized knurled knobs on both axes.
• Powder-coated aluminium head, 14″ x 7″ x 4″, weighing 6.6 lb (3.0 kg).
• Stainless steel tripod with adjustable legs and a spreader bar, 11 lb (5.0 kg), opening to a 42″ footprint.
• Wide height range: 36″ to the centre of the mounting bracket with the legs in, 53″ with them fully out.
• 16.7 lb (7.6 kg) assembled, and 42″ long when collapsed with the head attached.

Recommended Uses

• Visual observing with short and medium refractors up to the published 18 pound capacity.
• Lightweight Newtonian and Maksutov tubes within the same weight limit.
• Grab-and-go sessions where setup time matters more than tracking.
• Lunar, planetary and double-star work at moderate power, where the slow-motion cables keep the target centred by hand.
• Terrestrial and daytime use, spotting scopes included.
• Public outreach, where a mount that anyone can push to a new target is an advantage.

Compatibility and Accessory Notes

• Telescope weight: the published limit is 18 pounds. A tube close to that figure will feel better on it than one over it, and the diagonal, finder and eyepiece all count toward the total.
• Saddle fitting: Explore Scientific does not publish the dovetail standard the head accepts, so that row is absent below rather than estimated. Send us the dovetail bar on your telescope and we will put the question to our Explore Scientific rep before you order.
• Height: 36″ to 53″ to the centre of the mounting bracket covers seated observing through to standing observing with a long refractor.
• Tracking: this is a manual mount. Motion is by hand and by the slow-motion cables; there is no motor drive and no computerised pointing published for it.
• Transport: 42″ collapsed with the head on, 29.5″ with the head removed, so the head-off figure is the one that matters for a car boot.

Good to Know Before You Order

• It is an alt-azimuth mount, so it moves in altitude and azimuth rather than following the sky on one axis. For visual observing that is simply how you drive it. Long-exposure deep-sky imaging asks for an equatorial or a tracking alt-azimuth head, and we stock both if that is where you are heading.
• 18 pounds is the published telescope capacity, not the total including accessories. Weighing your tube with the diagonal, finder and heaviest eyepiece on it gives the number that actually matters, and we are happy to sanity-check it with you.
• The dovetail standard is not published. Rather than guess, we will confirm it with Explore Scientific for your specific telescope — ask and we will find out.
• The whole assembly is 16.7 lb. That is a comfortable one-trip carry for most people, though the head detaches if you would rather split the load.
• No telescope is included. The mount head and tripod are what ships. If you are pairing it with a tube, we can quote the two together.

Frequently Asked Questions

Is it difficult to set up?

No. The tripod legs extend and lock, the spreader bar sets the spread, the head bolts to the tripod, and the telescope goes on the mounting bracket. There is no polar alignment, no levelling routine and no power. From the boot of a car to observing is a couple of minutes, and the only decision along the way is how far to extend the legs.

What size telescope will it carry?

Explore Scientific publishes an 18 pound telescope capacity. Refractors in the 80mm to 127mm range typically fall well inside that, as do small Maksutovs and short Newtonians. Tell us your tube and we will tell you honestly how it will sit.

Does it track the stars?

Not by itself. It is a manual mount with slow-motion control cables on both axes, so keeping an object centred at high power is done by hand with the knobs.

What is the 45-degree tilt for?

Reaching the zenith. On a flat alt-azimuth head a straight-through refractor puts the eyepiece near ground level when the tube points straight up. Tilting the head moves the eyepiece back to a workable height.

How tall does it stand?

With the head fitted, 38.5″ at its highest point with the legs retracted and 55.5″ with them fully extended. Measured to the centre of the mounting bracket, which is the figure that determines eyepiece height, it is 36″ to 53″.

Can I use it during the day?

Yes. An alt-azimuth head with slow-motion controls suits spotting scopes and terrestrial observing as readily as it suits the night sky.

Bottom Line

In short: an 18 pound capacity alt-azimuth mount with worm gears on both axes, slow-motion cables, an adjustable 45-degree head tilt for zenith work, and a stainless steel tripod that reaches 53″ to the mounting bracket — 16.7 lb assembled and ready in a couple of minutes. If you would like us to check how your telescope sits on it, send us the model and the dovetail it uses and we will work it out with you.