Thursday, November 27, 2025

 

Smart Telescopes

&

Astrophotography

A smart telescope is an all-in-one automated imaging system, while a conventional telescope is an optical instrument that puts you in direct control of the observing experience.




This is the story of how revolutionary advances in electronic imaging technology have made the wonders of the deep sky both accessible and affordable even to raw beginners in observational astronomy through the invention of the smart telescope, replacing the human eye with a smart phone screen.

[This article is being posted on my blog today to coincide with the Brahmanda 2025 event organized by Rotary Midtown Mysore, dedicated to space sciences and astronomy, in which both Krishnamurthy and I are slated to speak on smart telescopes, astrophotography and astronomy apps.]

 

Telescopes – then and now

A decade ago, telescopes used to be something requiring an adequate knowledge of the night sky akin to reading a map, as well as considerable manual skills to zero in on the object of interest. Though less complicated telescopes of the “Go-To” variety had come into common use, these were not quite as easy to use as the term implied. All this has now changed with the advent of the smart telescope, though at a considerable disadvantage of not being able to see the image directly through an eyepiece.

The earliest commercially available "smart" telescopes such as the Vaonis Stellina emerged only in recent years, with their development starting around the mid-to-late 2010s. These devices are a modern category of electronically assisted computer-controlled telescopes designed for ease of use in amateur astronomy and astrophotography. 

[The Vaonis Vespera (see picture below) made its entry in Mysore skies two years ago when a visiting astrophotographer from the USA, Dr Manju Nath, captured the Orion Nebula in glorious detail from my home before a group of admiring enthusiasts. This provided me the motivation to go for my own smart telescope in the form of ZWO Seestar S50 a few weeks ago and place it in the hands of my long-time associates, particularly Krishnamurthy and Chiranjeevi, to put it to best use as evident later in this article.]

The show-stopper

The Unistellar eVscope, an early version of the smart telescope (pictured above), was first presented at the CES (Consumer Electronics Show) in 2017 and later won the Innovation Award in the ‘Tech for a Better World’ product category in the CES 2018. It caused quite a sensation, being able to acquire, track and photograph deep sky objects from even within a brightly lit Las Vegas city environment. The urban limitations for observational astronomy had been breached dramatically.

During the summer of 2017, the Unistellar team demonstrated the telescope capabilities to thousands of people in Europe and in the United States.  They had worked for two years to perfect their idea, building and testing several prototypes to finally create a compact, intelligent and powerful portable telescope that was easy to use.

Using its enhanced vision technology, the eVscope accumulates light, and can reach the light gathering power of telescopes ten times larger in diameter, so one can finally see colorful nebulae, galaxies millions of light years away, and faraway planets, objects that are too faint to be clearly seen through even large conventional telescopes. Thanks to its sensors, GPS and its internal map of millions of stars, this smart telescope could pinpoint and identify almost any object in the night sky, making deep sky astronomy easier and more informative than ever before.

Nebulae, star clusters, galaxies, extra-galactic supernovae, comets, fast near-Earth asteroids, and much more —they are out there every night, just above you in the sky, and they are inviting you to have a look.


Section A - Smart Telescopes

An overview

Smart telescopes combine optical hardware, motorized mechanics, and an integrated stack of electronics, sensors, and software to simplify and often automate the process of finding, tracking, and imaging celestial objects. They’re designed to let users—from beginners to experienced amateurs—capture useful astronomical images with less manual setup, less learning curve, and more repeatable results than traditional telescope + DSLR/CCD + third-party software workflows.

Historical background

The idea of an automated, user-friendly telescope has roots in several historical threads:

  • Mechanized mounts and clock drives (19th–20th centuries) first enabled tracking for long exposures.
  • CCD detectors and digital imaging (late 20th century) replaced photographic film, enabling electronic capture and computer processing.
  • Computer control of mounts and motorized focusers (late 20th — early 21st century) made remote and automated observing practical.
  • Consumer electronics (smartphone sensors, low-cost CMOS, embedded processors) and advances in software (plate solving*, autoguiding algorithms, image stacking) converged in the 2010s–2020s to enable the product class we call “smart telescopes.”

[*Plate solving is an astronomical technique that compares an image of the night sky to a star catalog to precisely determine the telescope’s location and orientation]

The modern commercial smart telescope packages emerged when manufacturers integrated precision optics, low-light cameras, Wi-Fi or app connectivity, and on-device processors to manage alignment, object catalogues, automated framing, autofocus, and image stacking without requiring separate PCs or extensive astrophotography expertise.

Early beginnings and evolution

Early attempts at simplifying astronomy included go-to mounts and simple “push-to” electronic setting circles. As digital sensors matured and became smaller/cheaper, small telescopes could be shipped with integrated CMOS cameras and onboard electronics. Two important evolutionary steps were:

1.      Go-to + autoguider integration — allowed the telescope to locate and track objects reliably for long exposures.

2.     Onboard image processing + apps — enabled users to control a telescope through a tablet/phone and to preview, align, and stack images in real time.

The combination of compact, sensitive CMOS sensors, fast processors, and smartphone user interfaces turned smart telescopes into consumer products: plug in, connect wirelessly, select an object from an app, and the device automatically finds, tracks, focuses, and produces stacked images, often with minimal user intervention.

Stacking

Stacking is one of the most important image-improvement techniques in astrophotography. Smart telescopes take many short exposures and combine them to raise the signal-to-noise ratio (SNR) and reveal faint detail while minimizing star trailing and tracking errors.

Why stacking works

  • Signal (from the sky object) adds linearly with each exposure.
  • Random noise (including thermal noise) grows at a lower rate. By stacking N frames, signal grows ~N, while random noise grows ~√N, improving SNR roughly by √N. So, in theory, it is possible to obtain a tenfold increase in SNR by stacking one hundred frames.

The broad picture

Smart telescopes have transformed amateur astronomy by lowering the technical barriers and providing immediate, gratifying results. They are ideal for beginners, educators, and those who want a portable, quick-to-use device for imaging bright deep-sky objects, the Moon, and the planets. For enthusiasts who want maximum control, depth, and detail, conventional modular astrophotography still offers more flexibility and performance.

However, the gap is closing: improvements in sensors, AI-based processing, and cloud/offboard computing are raising what smart telescopes can produce. Over the next few years one can expect smarter, more capable, and more modular designs that bring deeper performance while keeping the simplicity that made the first generation so popular.


Section B - The Seestar S50

The Seestar S50 (see picture above) is a low cost (US$ 500), high performance, addition to the world of smart telescopes, just the right piece of equipment to make the transformation from conventional telescopy to the current state-of-the-art variety.

What it is at a glance

  • The Seestar S50 is an all-in-one “smart telescope” from the Chinese ZWO company – optics + sensor + tracking mount + electronics integrated in a compact unit.
  • Key specs: 50 mm aperture, focal length 250 mm (f/5) with a triplet apochromatic refractor design (see illustration below).
  • Sensor: Sony IMX462 (colour); resolution ≈2 MP
  • Connectivity/app control: WiFi (2.4G & 5G) + Bluetooth; controlled via smartphone/tablet app.
  • Mount/tracking: Alt-azimuth style mount built in; uses plate solving and GoTo automation to locate celestial objects.
  • Portability: Weighs around 2.5 kg and comes with a compact case.
  • Battery life: Up to ~6 hours on a full charge (via internal battery).

What it’s good for

  • Aimed at beginner to intermediate astronomy hobbyists who want a quick-setup, relatively plug-and-play experience - “great for exploring, outreach, and enjoying astronomy with your friends and family.”
  • Suitable for capturing the Moon, the Sun (with appropriate solar filter), brighter deep-sky objects (DSOs) like nebulae, star clusters, galaxies (within its limitations) from relatively light-polluted locations.

Where it is less suited

  • Because of the short focal length (250 mm) and small sensor, it’s not ideal for high-resolution planetary imaging (Jupiter, Saturn close-ups) or very faint deep-sky imaging over long exposure times.
  • The field of view is relatively narrow given the sensor size; some targets may appear truncated or smaller than expected.

Advanced attachments & options

When we talk “advanced attachments and options” for the Seestar S50, these are the accessories and expansion possibilities one should know about:

Included items / standard attachments

  • A small carbon-fibre (or lightweight) tripod (table-top style) is included.
  • Solar filter included (for safe solar observation) in many bundles.
  • Built-in dew heater, dual-band light pollution filter (for O III / Hα emission) inside the unit.

Upgrades / optional attachments to consider

  • Larger/height adjustable tripod: The included tripod is very compact, which means low height. If you prefer comfortable viewing or live stacking while standing or sitting, a taller, stable tripod will help. This will also ensure that the tripod doesn’t trip over due to the weight of the attached devices.
  • Adapter for standard tripod threads: The unit uses a 3/8″-20 mounting thread, so if your existing tripod has ¼″-20, you’ll need an adapter.
  • Power bank or external power: Although it has internal battery, you might choose to run it from a USB-C power bank for extended sessions (especially if you are imaging from remote sites).
  • Optional filters or external accessories: While the device has built-in filters (dual-band L-pollution filter, solar ND filter), for more serious imaging you might consider external filter wheel, narrowband filters, although the unit’s design may limit upgrade potential compared to modular gear.
  • Mount upgrade / wedge: True equatorial tracking needed to avoid field rotation during longer exposures — the Seestar’s built-in altazimuth mount limits very long integration times. This can be overcome with add-on wedges or external mounts like the one pictured below.

[The Seestar TH10 Fluid Head from ZWO allows the Seestar smart telescope to operate in equatorial mode, correcting for the earth's rotation while tracking stars during photography exposures. It is also a smooth-operating mount for cameras and optics.]

Software & firmware options

  • The Seestar app receives regular firmware updates; for example, a free update unlocked “mosaic/framing mode” to capture larger sky areas.
  • Live-stacking is built into the unit: you can view incremental improvements as exposures add up.

Key performance and specifications

Specs summary

  • Aperture: 50 mm
  • Focal length: 250 mm (f/5)
  • Sensor: Colour CMOS (IMX462) ~2 MP resolution
  • Internal storage: 64 GB (so you don’t necessarily need external memory) in many models.
  • Connectivity: WiFi (2.4/5 GHz) + Bluetooth + USB-C.
  • Weight: ~2.5 kg— portable.
  • Modes: Solar mode, Lunar mode, Scenery mode, Stargazing mode.

Practical considerations

  • Light pollution: If you are within or near the city, light pollution will impact deep-sky imaging. The built-in dual-band filter (for OIII/Hα) helps with emission nebulae, but galaxies and broad-spectrum objects will still be affected.
  • Target selection: With its wide field and short focal length, the S50 is best for large, bright nebulae (e.g., Orion Nebula), star clusters, and wide-field galaxy views. For very small, faint galaxies or detail-rich planetary work you might find limitations.
  • Setup convenience: The portability and integrated nature are huge plus points. You can set up on your balcony or backyard without needing complex alignment. Easy smartphone connectivity and app control are notable features.
  • Tripod height & stability: Because the included tripod is very low (~27 cm max extended) users may need to place the unit on a table or use one’s own tripod for ergonomic height.
  • Power & battery: In a warm climate, battery life should be near the rated 6 h. One can use external USB-C power bank for longer sessions.
  • Weather & dew: Even in tropical/sub-tropical regions, dew can be a factor. The built-in dew heater is very helpful.

Imaging capabilities: stacking, techniques & limitations

Live stacking & workflow

  • The Seestar S50 supports live stacking: each new sub-frame adds to the stack and you gradually see improved image quality on your phone/tablet.
  • Typical workflow: level the unit → connect app → select target from catalog → auto-slew/go-to → start capture with stacking → let it run for X minutes → review/export images. Reviewers highlight how quick this is.
  • Because it uses alt-az mount, be aware of field rotation if you stack long exposures (over tens of minutes) without de-rotation: some users report corner stretching over longer time.

Techniques & tips

  • Dithering: Although internal stacking is automatic, if you export raw frames to desktop for deeper processing you can apply dithering (small shifts between frames) to reduce fixed-pattern noise, but the unit may limit this compared to full rigs.
  • Exposure time: With short focal length you can use shorter exposures (10-30 s) and still capture decent signal. 20–30 s sub-frames are often adequate for nebulae.
  • Stacking many frames: For best results stack many frames (20 minutes up to 1 hr or more) may be needed to improve SNR.
  • Export & post-processing: If you wish to go beyond casual, you can export to FITS or TIFF format and use advanced software (PixInsight, DeepSkyStacker) but raw data is limited by sensor size/resolution.
  • Filtering: The internal dual-band filter helps with emission nebulae under light-pollution. But for broadband objects (galaxies, clusters) you might turn the filter off or consider external filters to improve colour/passbands.
  • Solar & lunar imaging: The S50 includes solar mode (with ND filter) for safe Sun observation and lunar mode for Moon - good for outreach and easy sessions.

Limitations

  • Limited aperture (50 mm) means less light gathering compared to larger telescopes—so faint deep-sky objects will be harder to resolve with high detail.
  • Alt-az mount means field rotation becomes a concern with long integrations.
  • Pixel scale and FoV: Some critics observe that the sensor’s shape (long vertical) and small resolution limit capturing very large objects fully or capturing very fine detail.
  • Upgradability: Because it’s an integrated unit, you have less modular flexibility than a full astrophotography rig (swap in different cameras, larger scopes, equatorial mounts) — so think of this as more of a “smart-scope” than full professional kit.

In summary: The Seestar S50 is a fun, well-engineered smart telescope that gives you a very manageable entry into astrophotography without dealing with the full complexity of traditional rigs.

Pros:

  • Very easy to set up and use — quick start for stargazing and imaging.
  • Portable, integrated unit — less gear to assemble, fewer cables, simpler workflow.
  • Good for wide-field views, shareable images, educational/outreach use.
  • Modern connectivity and app features; updates adding value.

Cons:

  • As you move toward more advanced/high-resolution imaging, it may hit limits (aperture, focal length, mount type).
  • If you want fine detail (planetary close-ups, tiny galaxies) or very long exposures, you’ll outgrow it.
  • Some ergonomic/tripod/height issues to manage.

Final comments: If your primary goal is to “get out there, point it, capture the sky, enjoy astrophotography without massive setup headaches,” then this is a strong candidate. If later your ambition grows, you can consider supplementing or upgrading.

In a nutshell, a smart telescope is a conventional telescope that has been integrated with a computer, a camera, and sophisticated software. Its primary goal is to automate the process of finding and viewing celestial objects, making astronomy accessible to beginners and more convenient for experts.

A conventional telescope is essentially a sophisticated "light bucket." Its job is to gather light and provide optical magnification, but the user is responsible for everything else.




Section C - Our Experience 

Krishnamurthy, Chiranjeevi and I have lost no time playing with our Seestar S50, but we have not been able to invest adequate time largely because of persistently cloudy weather in and around Mysore.  Nevertheless, we have made encouraging progress from the initial baby steps, including the use of the TH10 Fluid Head, a sturdy tripod and other accessories as can be seen in the picture and video clip below:




Our astrophoto album

We take pride in presenting the following selection of our best pictures so far. Thanks to its 'smart' stacking and image processing features, we have been able to 'see through' the urban light polluted skies and get some good pictures, but no amount of smartness could have worked in cloudy skies. Large parts of the sky have still been out of bounds. 

A – Deep Sky Objects (taken in Bortle 7/8 skies)

 


B – Solar System Objects


C – Terrestrial Objects

 

Glossary of Pictures

A – Deep Sky Objects

1)      M42, NGC 1976 Orion Nebula.

2)      Caldwell 49, The Rosette Nebula.

3)      M33, NGC 598, Triangulum Galaxy.

4)      NGC 1499, California Nebula.

5)      NGC 2024, Flame Nebula.

6)      NGC 2174, Monkey Head Nebula.

7)      IC 443, Jellyfish Nebula.

8)      M 31, NGC 224, Andromeda Galaxy.

9)      Comet C2025 A6(Lemmon).

10)   Barnard 33, IC 434, Horse Head Nebula.

11)   M1, NGC 1952, Crab Nebula.

12)   NGC 7293, Helix Nebula.

13)   M15, NGC 7078, Great Pegasus Cluster (Globular Cluster).

14)   C14, (NGC 869 and NGC 884) Double Cluster.

15)   NGC891, Silver Sliver Galaxy.

B – Solar System Objects

16)   The Sun with its spots.

17)   Sun spots magnified 4×.

18)   Waning Gibbous Moon.

19)   Waning Crescent Moon.

20)   A crescent horn of the Moon magnified 4×.

21)   Tycho, Lunar impact crater.

C – Terrestrial Objects (Both from a distance of about 20 km)

22)   Lalith Mahal Palace Hotel, Mysore

23)   Temple on Chamundi Hill, Mysore

 

Appendix A

 A Comparison between the smart and the conventional

Feature

Smart telescope

Conventional telescope

Primary Interface

Smart phone/App

Eyepiece/Direct viewing

Finding objects

Fully automated

(Tap on object in App)

Manual (Use of charts and star-hopping or basic ‘go-to’)

Setup & Alignment Automated

Uses GPS and plate-solving to align itself

Manual - Requires you to polar align (for equatorial mounts) and calibrate on known stars

Viewing Experience

Digital screen. live-stacked, processed images. Can see color in faint objects

Direct optical view. You see with your own eye. Views of galaxies/nebulae are often faint and gray

Skill Level

Beginner-friendly. Almost no prior knowledge needed

Steeper learning curve. Requires learning the sky and telescope operation

Ease of Use

High. Portable, quick to set up, and simple to operate

Varies. Can be bulky, complex, and time-consuming to set up

Astrophotography

Built-in and simplified. The primary function. Great for deep-sky objects

Complex and expensive. Requires additional cameras, guide scopes, and software

Social Sharing

Easy. You are already looking at a digital image; screenshot and share

Difficult. Requires attaching a phone holder to the eyepiece for basic photos. The "Go-To" Telescope: A Middle Ground 

[It's important to mention the "Go-To" telescope, which sits between these two categories. A Go-To scope has a computerized mount and a hand controller with a database. It can automatically point to objects, much like a smart telescope. However, you still look through an eyepiece for a direct optical view, and it often requires a more involved manual alignment process. It's "smart" in pointing, but not in image capture and processing.]

 

Appendix B

How a Smart Telescope Works (The "Smart" Part)

Think of a smart telescope as a robot that knows the sky.

1. It Has a Brain: Inside the telescope is a small computer running on an internal battery.

2. It Has an Eye: A built-in digital camera captures what the telescope is pointing at.

3. It Knows Where It Is: Using built-in GPS, sensors, and the time, it calculates its exact position on Earth and how the sky is oriented above it.

4. You Control It with an App: You use a smartphone or tablet app to select an object from a vast database (e.g., the Andromeda Galaxy, the Ring Nebula, Jupiter).

5. It Finds Itself Automatically: The telescope's motors then automatically slew (move) to point precisely at that object. It uses plate-solving technology—taking a picture, analyzing the star patterns, and comparing them to its internal star chart to ensure it's perfectly centered.

6. You View on Your Screen: You don't look through an eyepiece. Instead, you see a live, processed view of the object on your phone or tablet screen. Many smart telescopes can even stack images in real-time to reduce noise and bring out more detail.

A conventional telescope relies entirely on the user's skill and knowledge.

1. It's a Manual Tool: It consists of an optical tube (using lenses for refractors or mirrors for reflectors) and a mount.

2. You Find Everything: You must learn the night sky. To find an object, you often start by "star-hopping"—using known stars and constellations as stepping stones to locate faint fuzzies.

3. You Look Through an Eyepiece: Observation is done by placing your eye directly at an eyepiece, which provides the magnification. This is a direct, optical view.

4. It Requires Skill and Patience: Setting up the mount, aligning it (especially for equatorial mounts), and finding objects takes practice and a good understanding of celestial mechanics.


                                                                     Appendix C

A mosaic of deep sky pictures taken with Seestar S50 as presented in the product promotional website (see here).

Bottomline

Perhaps inevitably, here is the latest in smart telescopes - the DWARF Mini!