Product Description
This Astro-Tech AT102ED refractor has:
• 102mm f/7 fully multicoated doublet optics using FK-61 ED glass
• dual-speed 2" Rack and Pinion focuser with built in rotator
• 2" and 1.25" brass compression ring eyepiece holders
• split tube rings with detachable Vixen-style dovetail for installation on virtually any mount
The AT102ED is bringing ED optics to you at a fantastic price. When this scope was available in 2008 the retail price was $995. The reintroduction not only has a much lower price, but it has better mechanics as well as advancements in the optical assembly and polish. You get a 2" Rack and Pinion focuser with a microfine 11:1 fine-focusing ratio finished in our Aston Martin Grey body. You get dual split mounting rings with a detachable 8" Vixen-style dovetail plate that lets you mount your AT102ED on virtually any altazimuth or German equatorial mount. The finely-machined Astro-Tech AT102ED comes with both 2" and 1.25" eyepiece holders using non-marring brass compression rings that won’t scratch your star diagonal or eyepiece barrels.
2019 the 102ED has an improvement that has been asked for many, many times over. The scope now comes with a retractable dew shield and a Vixen Finder shoe.
2023 more improvements for the 102ED. The focuser can now rotate and the scope comes standard in a cordura nylon case that has room for accessories as well as your scope.
As with all Astro-Tech scopes, the AT102ED gives you fully-multicoated ED optics that are essentially free of the annoying halo of unfocused violet light (chromatic aberration) that mars the bright-object images of lesser scopes, despite the fast focal ratio, and even at very high magnifications.
Features of this Telescope . . .
• ED doublet refractor optics: 102mm (4") aperture, 714mm focal length, f/7 focal ratio doublet optical system using an FK-61 ED (Extra-low Dispersion glass) element to reduce spurious color halos and fringing to vanishingly low levels.
• Fully multicoated optics: The AT102ED objective lens has the latest state-of-the-art antireflection multicoatings on all air-to-glass surfaces for high light transmission and excellent contrast. This can easily be seen by looking into the objective lens of the scope. Virtually no reflection of your face will be seen. It’s a sure sign that the high transmission coatings are doing their job, by letting virtually all the light enter the scope, rather than reflecting some light back to your eye.
• Internal light baffles: Three contrast-enhancing knife-edge internal light baffles and a specially darkened tube interior provide truly dark sky backgrounds and high terrestrial contrast. The edges of the lenses are blackened to reduce internal reflections and further improve image contrast.
• Dew shield: A retractable dew shield slows the formation of dew on the lens in cold weather to extend your undisturbed observing time. It also improves the contrast, similar the lens shade on a camera lens, when observing during the day or when there is excessive ambient light at night, such as a neighbor’s backyard security light. The tube measures 24” long with the dewshield retracted and 30" long with it extended.. A slip-on metal dust cap for the dew shield is standard.
• 2" Rack and Pinion rotating dual-speed focuser: The precision-made no-backlash dual speed 2" rack and pinion focuser is based off our EDT line of telescopes. Very smooth, and very robust. There are two coarse focusing knobs. The right knob also has a smaller concentric knob with an 11:1 reduction gear microfine focusing ratio. This provides exceptionally precise image control during high magnification visual observing and critical 35mm or CCD imaging. The focus knobs have ribbed gripping surfaces so they are easy to operate, even while wearing gloves or mittens in cold weather.
• Long focuser travel: The long 85mm (3.35") travel of the focuser drawtube helps keep the overall scope length reasonable for convenient travel and storage. The long drawtube length also permits switching between visual or photographic use with no add-on extension tubes needed. The drawtube has a scale marked in 1mm increments so you can note individual focuser positions for easy return to the correct focus when switching between visual use and photography. A drawtube lock knob underneath the focuser lets you lock in your photographic focus.
• Compression ring eyepiece holders: The focuser’s drawtube terminates in a 2" eyepiece holder that uses a non-marring soft brass compression ring to hold a 2" star diagonal and/or accessories in place. The compression ring won’t scratch the barrel of your star diagonal and accessories as an ordinary thumbscrew can.
A supplied 1.25" accessory adapter slips into the 2" eyepiece holder to let you use a 1.25" star diagonal, image erecting diagonal, or photographic accessories. Like the 2" eyepiece holder, the 1.25" adapter also uses a non-marring soft brass compression ring to hold 1.25" star diagonals and accessories in place. If you are partial to 1.25" eyepieces and need an outstanding diagonal for this scope, consider the 99% reflectivity Astro-Tech 1.25" dielectric diagonal #AT1D. It's a Sky & Telescope Hot Product for 2007. An Astro-Tech 2" dielectric star diagonal #AT2D will give you the same 99% reflectivity performance with 2" eyepieces.
• Tube finish: The optical tube and lens shade are finished in a white powder coat while the focuser and trim are Aston Martin Grey anodized. The scope weighs 9.1 lbs with mounting rings attached.
• Tube rings and dovetail mounting plate: The 105mm o. d. body of the AT102ED comes with a pair of hinged split mounting rings and a detachable 8" long dovetail mounting plate. The dovetail plate fits directly into the head of many equatorial and altazimuth mounts. It will fit, without modification, Celestron Advanced Series and Meade LXD-75 go-to mounts; the Vixen Porta altazimuth mount; and Vixen Great Polaris and Sphinx mounts, among others. The longer length of the dovetail plate lets you balance the AT102ED more easily fore and aft in a mount’s dovetail slot. This lets you quickly accommodate changing balance conditions as you exchange an eyepiece for a camera, a 1.25" diagonal for a 2" diagonal, etc.
In addition, the dovetail plate can be unbolted from the split rings to allow you to mount the rings directly on other equatorial mounts – for example on the D-plate used on Losmandy mounts – something that is difficult to do with the short mounting foot on competitive clamshell rings. The dovetail plate also has a 1/4"-20 thread mounting hole that allows it to be installed on any suitable heavy-duty camera tripod that has a standard 1/4"-20 thread mounting bolt.
The included 27" x 12" x 8" cordura nylon case has room for some accessoires and provides great protection for your telescope.
Tech Details
Aperture | 102mm |
---|---|
Focal Length | 714mm |
Focal Ratio | f/7 |
Heaviest Single Component | 9 lbs. |
Weight | 8 |
Optical Coatings | Multi-coated |
Supplied Eyepiece | None |
Telescope Type | Refractor |
View Finder | None |
Warranty | 1 year |
Reviews
I'm floored. The short of it? Yes, this is a REAL ED DOUBLET. No lie here. I mean sure, it's there at higher mags but what a GREAT reduction of blue fringe compared the the 70mm Ranger.
But what about the sharpness? Can it REALLY hold up at 100x per inch like the Ranger did? Seeing a crows beak years ago on a crow 100 feet away up a tree I was astonished at the sharp detail. The texture around the baked nostrils, wear and tear. Hardly a practical working power with this scope but what a feat. I never forgot it. I picked pine needles atop a fir also, 100 feet away. Sure, I did the 200x which is its 50x per inch mag but hell, I wanted to floor it. I put in a 3.2mm ocular with a 2.5 TV Barlow for 557x and its view was nothing short of astonishing for a retailing OTA of $598.00 !!!! This is less than the Ranger cost in 1997!!!! The workmanship is all that. So good for the price point I really feared they HAD to cheap out on the glass. It's gotta be a little rough somewhere right? Absolutely wrong. Again, nothing practical about nearly 600x from a 4" refractor but it was done to see if it was ☆feat worthy☆. I'm amazed. No, it's not a Petzval or a Christen design (and execution. What it IS really, is a economically priced refractor punching way way above its weight.
Etched sharpness. A little CA. Get over it. (Posted on 11/9/2022)
The focuser was flawless and it was a joy to have fine focus capabilities. The overall construction of this scope is that of one costing many times more. It is built like a tank and one that I'm sure will be with me for many years. (Posted on 2/13/2022)
Saturn and Jupiter were very satisfying with nice detail. Epsilon Lyrae, the famous "double double", was wonderful. The splits were precise and quite beautiful. The star test was excellent and the star images through this telescope are excellent too.
I must mention the mechanical construction...very impressive. The two-speed focuser, while somewhat tight, is very smooth and positive. I just don't see any 4 inch refractor that can come close to this telescope at $600. It would be a great deal at $800, or more. Great job Astronomics! (Posted on 11/3/2021)
Build quality is, of course, beyond reproach. Everything exudes quality on this scope. The dew shield feels solid and doesn't budge after you set it where you want. The focuser is excellent at this price point and includes a tension adjuster.
I use mine at least 50% of time for terrestrial viewing and it excels at that too. My neighbor (1 acre lots) across the street has 100 foot Sycamores in his yard. I was watching a crow at the top of one of them when I noticed an ant crawling up the crows foot. Yep, it's that good.
I also have an 8" EdgeHD and have developed an interest in double star observation. The AT102ED is the perfect companion for my interests. Stars resolve to pinpoints with no false color except on the brightest targets. I can't wait to get this baby up to my parents place in Colorado.
Last and certainly not least, it's an amazing grab and go telescope. The SkyWatcher AZ-GTi has no problem handling the AT102ED.
(Posted on 4/21/2020)
Y'all could add one of those standard aluminum foam-lined cases, up the price to $799 or even $899, and they'd still sell. My AT102 confirms a lot of the buzz about this ED. If you're in the market for a "fast" 100mm APO, give this one some serious consideration. This doublet packs a lot of punch -- at a very reasonable price.
~ Bomber Bob (Posted on 12/4/2019)
All this said, my SCT still does better at the faint fuzzies simply because of the greater aperture. The one exception to that is M31, which I can now see in (almost) it's entirety. That is a stunning view!
The fit-and-finish show this is very much a quality scope; nothing was done 'on the cheap'. While this may not be my only refractor over the years, this is certainly no 'introductory' instrument. This will serve a serious observer very well for many years.
I'd say this scope is at a sweet spot for cost vs performance/quality and well worth the price. (Posted on 10/4/2019)
(Posted on 9/8/2019)
My primary passion are double stars. I was concerned about the "only 710" mm focal length but that has not been an issue. I have been able to routinely power up to 158x (9mm with 2x barlow) to split doubles. I am routinely in the 2.3" separation splitting zone.
I can see colors much better with this scope. The red of the Garnet Star exploded with color. Alberio is a pure joy.
The slo-mo controls are great to use and the Twilight 1 has provided a steady mount.
I use inexpensive Plossl eyepieces (Meade and the Astronomics) and am rewarded with wide FOV and sharp images.
Great scope at a wonderful price. Excellent value.
Ed (Posted on 8/7/2019)
Jupiter showed a tiny bit but it didn't affect the view.
Antares was perfect.
Vega was real close.
The moon was fine except as you suspect the rim has a really tiny purple line. No big deal.
Unlike other achromats the view isn't affected just that little thin color fringe. IF you really focus well it goes away. Hey built in focus finder! What made me title this is the view. The contrast and detail in the view are outrageous for the price. It's one hell of a scope. Ok people complained about the focuser. Fixed. The new one has to be made by starlight as it is the exact replacement one I bought for my C8. That was 300.00 by itself. Only wish would be it came with a case. Any case at all really. Buy it Now stop reading reviews.
Eyepiece makes a difference....just saying don't always blame the scope. (Posted on 7/2/2019)
The the overall build and focuser are solid and the views are excellent. I plan to use this as an entry level imaging scope as well as a grab and go.
Yet another great Astro-Tech product! (Posted on 1/14/2019)
I have had my at102 side-by-side with several other 100 mm Apo doublets, all of which retail for much more, and the Astro Tech is equal to or better than the majority. False color is minimal even at high power on the moon. I'm not sure what magical coatings are used on the objective but looking at the reflection of a lamp in the optic produces almost no reflection whatsoever. This seems to give the Astro Tech an edge over some of my other 4" refractors in image brightness by allowing nearly all the Starlight to reach the eyepiece. My advice........get em while they last! (Posted on 1/10/2019)
The optical quality is good.
False color is barely noticeable in focus. Out of focus it quickly shows up.
The focuser is very good for a telescope in this price range. The other hardware is very nice, too.
Through the summer Mars always showed a polar cap and surface albedo features were visible through the dust storm. I preferred this to my C6 and C8 for observing Mars.
Cooldown is very quick. I have this on an alt-az mount in my front room able to be taken outside in one hand at a moment's notice.
I've used it for some astrophotography with a DSLR on an AVX and there is some bloat on stars but it isn't terribly objectionable.
It is a great value of a telescope. (Posted on 12/26/2018)
Fit and finish are impressive. OTA feels solid, and 102mm is the ideal combination of portability and performance.
Do I recommend this OTA? Of course! hands down, one of the best telescopes you can have in your arsenal. (Posted on 12/11/2018)
This is my second refractor, and my first ED scope. I bought this as an upgrade from my four inch Celestron achromat, and I’m sure glad I did! The AT102ED is an amazing scope! At first sight I could tell the mechanical quality is much better, the paint job looks great and the focuser is strong and smooth. The color correction is Miles ahead of the achromat, and it was obvious viewing Jupiter that the color error is very small compared to the achro. I think to get a better mechanical/ color corrected scope you're looking at $2000 and up, and that makes the AT102ED a veritable bargain. (Posted on 11/4/2018)
This is scope has given me the best return on investment of any astro-equipment I've ever purchased. For $599 I have a light weight, well constructed 4" refractor with ED glass and focuser that doesn't have to take back seat to any scope costing twice as much - or more. Coupled with a Voyager II alt-az mount, it is easily picked up (28 pounds) and carried outside on a moment's notice. A couple older TeleVue eyepieces and barlow lens live in the tripod spreader, so everything is right there in just a single trip. (A second trip brings the equally important observing chair and adult beverage.)
From richest-field capability (nearly 3 1/2 degree true field of view), to high powered viewing at 200x and everything in between - this is without a doubt, the most versatile telescope you can buy for the money. (Posted on 10/16/2018)
Highly recommended! (Posted on 10/6/2018)
All hardware is beautifully finished and performs well. Focuser is smooth for both fast and fine adjustment.
All and all a great scope that outperforms it's price.
(Posted on 10/6/2018)