Explore Scientific Twilight 1 altazimuth mount


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Standard shipping: $17.95
The solid and stable Explore Scientific Twilight I light-to-medium-duty altazimuth mount and tripod has geared slow motion controls.  It weighs only 17.6 pounds, yet has a payload capacity of 18 pounds. 
Our Product #: TWI-ONE
Explore Scientific Product #: MAZ01-00

Product Description

The Explore Scientific Twilight I is a solid and low-vibration light-to-medium-duty altazimuth mount and tripod designed to quickly and easily accept small to medium sized refractors in the 80mm to 127mm range. With a payload capacity of 18 pounds (8.2 kg), even light weight, fast focal ratio Newtonians will match up nicely with the Explore Scientific Twilight I mount. For payloads greater than 18 pounds, consider the bigger Explore Scientific Twilight II mount.

The Twilight I alt-azimuth mount head is made of powder-coated aluminum. There are worm gear slow motion controls on both axes to let you smoothly follow the motion of the Moon, planets, and deep space objects across the heavens. The adjustable angle head can tilt forward or back at a 45° angle, as well as point straight up, depending on the length of your optical tube and your observing preferences. The slow motion control cables on the vertical and horizontal axes are easy to turn smoothly, even with gloves on in cold weather, due to their over-sized knurled control knobs. 

A small wrench is included with this package If you need to make quick adjustments to your mount in the field. It is stored in the fork arm and held in place with a magnet, so it is a snap to access the wrench and then store it safely away when done. It is a small thing, but an adjustment wrench is one less tool you will need to remember to bring with you on observing sessions.

The chrome-plated steel tripod of the Explore Scientific Twilight I mount has adjustable height legs. It has a wide foot print of 42 inches with the legs fully extended, which makes the tripod very stable. A spreader bar locks against the inside of the legs for maximum rigidity to keep vibrations to a minimum. With the legs fully retracted, the tripod is 38.5" high at highest point, and 36" to the center of the mounting bracket. With the legs fully extended, the tripod is 55.5" high at highest point, and 53" to the center of the mounting bracket.

The Explore Scientific Twilight 1 tripod weighs 11 pounds (5 kg), the head weighs 6.6 pounds (3 kg), for a total weight of 17.6 pounds (8 kg).

Tech Details

Weight 17.6 lbs.
Warranty 1 year, extendable to lifetime


Review by:
I received mine and assembled it per the instructions and it wasn't adjusted right as the whole head rocked back and forth. There is a couple of YouTube videos that show you how to take it apart and fix the offending lock nut. Shouldn't have to do that just to get it to work. Also the arm's lightening hole is to big and it loses stiffness because of it. I put an 1/8th " thick piece of aluminum on it bolted in six places took a lot of high power shaking out with my 127 Maksutov at 200x. I've seen others use plywood to stiffen it up. You have to use the 135 degree positions as the zenith position is too short except for the smallest scopes or have your scope front heavy so the diagonal fits, but it won't be steady. The hand controls are alright, but one is really too long. I bought a short one to replace it. After fixing and modifying it is pretty decent, can put an f/7 102mm on it with 2" diagonal and it was fine up to 150x and the higher towards zenith you aim it the steadier it becomes, so if you plan your session right you can go to 200x easy. Without the modifications it is a lightweight mount that weighs too much, but the price is good. (Posted on 2/7/2024)
Review by:
I found the mount to be fairly steady with a 10 lb refractor. However, it is not possible to pivot to near the zenith in any of the three mounting positions of the arm. There are two reasons. First, the mount does not have a pillar, and a slow motion cable usually bumps into the legs. Second, the optical tube is placed over the vertical axis, which limits clearance under the focuser. In contrast, mounts such as the Twilight II place the load off to the side. Not very impressed with the saddle, which uses two set screws that mar the dovetail on each use. I switched to a Stellarvue saddle with handle and found this setup much easier to use (esp not grabbing the diagonal to move the scope). (Posted on 10/31/2019)
Review by:
This is a decent medium/light duty mount. The legs are sturdy 1.5” tubular steel and the controls are smooth. This finish and function are nice and the angle of the head is adjustable. Originally, I planned to use this with a 10 pound 4” f/6.5 refractor, but I find it works better with smaller scopes, like 80mm f/5. For supporting a ‘reasonable’ weighted scope in an orientation capable of reaching zenith, I give this mount 3 stars. It gets 5 stars for handling smaller scopes, for an average of 4 stars. The mount is a good grab-and-go option and a decent valve for the money. There are a few pleasant surprises like the spring-loaded clutch locks and metal spreader bar. I’ve enjoyed the mount for 3 years now and have experienced very good customer service from Explore Scientific with their products. (Posted on 10/31/2019)
Review by:
I have used this mount with my Celestron Nexstar 5SE SCT. Easy to setup with dovetail. Very sturdy and dampens down very quickly. The slow motion controls are very smooth for tracking. I plan to purchase other telescopes to use with the mount in the near future. If I can get my kids interested, I might have to purchase a second TW1 AZ mount to have two scopes running at once. (Posted on 8/15/2019)
Review by:
I purchased this mount with the AT102Ed and have been very satisfied. It is steady at low and medium power and it dampens quickly at 158x.

My scope slo mo controls rubs against the focus control of the scope at steep angles. Need to adjust somehow. This is used as grab n go with the scope. It is a bit heavy but manageable.

Ed (Posted on 8/7/2019)
Review by:
I got the Twilight I mount in a package deal with my ES 152MM Mak-Cas. While the 17 pound 152 Mak with 2" eyepiece, Reflectix insulation, and a Celestron C6/C8 dew shield is at the maximum capacity of 18 pounds; the Twilight I mount supports it well.
The slow motion controls are smooth with no binding or play in the gears, the locking clutches operate smoothly and lock securely, the mount arm is beefy, and the tripod is stout. (Posted on 7/24/2019)
Review by:
I use with an ES 102 Essential refractor, a 80 mm refractor and a 60 mm refractor, and sometimes with the 60 mm piggybacked on the 102. interchange is quick and easy. Stability is quite good even with the two scopes mentioned mounted at once. Like the versatility and the quick and easy setup. (Posted on 7/23/2019)
Review by:
I've used this mount for a few years with my 60mm solar Ha telescope. It's very solid with a smooth geared action. It's also light enough in weight to be easily set up; I leave the solar scope on this mount and tote the whole setup outside. Highly recommended. (Posted on 7/22/2019)
Review by:
I have had this mount for over a year. I use it back and forth between my maksutov and my AT72 and it is a gem for the money spent. There is some shake to it I find, if you loosen the clutches a bit too much and free swing the mount in alt/az. If you only slightly snug them until you have some "stiction" you'll be much happier. Tighten everything down and the slow motion controls are absolutely fantastic. The mounts base (legs) are very sturdy and solid. Only thing that I wish that it had were degree marks in alt and az so that one could use this mount in conjunction with todays apps for directly finding objects from celestial coordinates. (Posted on 11/25/2018)
Review by:
I currently am using this mount in conjunction with my 127mm Orion maksutov. Holds it very well with almost no movement even during moderate wind gusts. The mount has very smooth axis' and the addition of the slow motion controls only makes that smoothness more apparent.
I really only have two main issues with this mount. First, it is a little bit too short for me as I am a relatively tall person at 6ft. I do unfortunately have to bend a bit when using this though it's not too bad unless after very extended lengths of time. My other issue with the mount is just the size of the mount. It is enormous, and quite heavy too. I know that adds to the stability but it makes getting outside a pain and keeps it from being a grab and go mount. For that reason, it's my second favorite mount behind the Orion Versago II. (Posted on 11/24/2018)
Review by:
I say sturdy because it is made of steel that is quite solid. I have a hard time tightening the legs as they sometime slip. May be my hand dexterity. I have removed the head and put on alternate heads as it removes easily with 4 screws. Mine had a complete set of instructions with tools to tighten and disassemble it if needed. I uses it with my Celestron C6A and 80mm 80ED CF scopes. It holds both with ease. I bought a strap to carry it on my shoulder. Slightly heavy to carry but very well balanced weight. Great tripod. (Posted on 11/14/2018)
Review by:
This is very light, compact, quick to set up and easy to use. I find it works well at very low powers with a 120mm F/5 refractor, and at medium powers with a C6. Over 150x it will wobble with a C6 (2+ seconds dampening) but is still adequate. For travel or grab&go they make a great combo. I have tried a 4" F/10 refractor on it but did not find the mount adequate for anything but sky sweeping at lowest powers. (Posted on 10/26/2018)
Review by:
Great for up to f/9 4" refractors and at least a Celestron C5, this mount is the best Alt-Az I've ever used. Smooth slewing allows easy target acquisition and the ability to fall right into slow-motion guiding and back to slewing without locking and unlocking clutches makes this mount an effortless please to use. The design accommodates different scope designs well and is easy to configure. Sturdy, it is surprisingly light weight, my wife has little trouble carrying this mount and the refractor out to use. If I could change anything about this mount it would be for ES to offer a purpose-built extended pier for it, so a tall guy like me could use it while standing. (Posted on 10/24/2018)
Review by:
I have owned the Twilight I mount for about a month and a half. I use this mount with a Sky-Watcher ProED 100 OTA that weighs about 12 pounds including the 50 mm finder and 2" diagonal that came with the OTA plus an eyepiece. It is very stable with this load and tube length, although it does shake somewhat when I focus. It replaces a Vixen Porta II alt-az mount that came with a Vixen 80 mm OTA that weighs about two pounds less than the ProED 100. Even though the Porta II is rated at 20 pounds, two pounds more than the Twilight I, the latter is much more stable than the Porta II when used with the ProED 100 OTA. The slow motion controls are very smooth on both axes. The tripod legs are also quite good. My mount did NOT come with a manual, just a one page "Quick Start Guide" which has the tersest of assembly instructions, which are inadequate. However, after I was able to get the mount together, it is definitely a keeper. If I downgraded the rating for the lack of a manual, I would give it 4 stars. (Posted on 8/4/2017)
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