I recently received my eVscope from Unistellar and after just a few sessions with it, I thought I would share my thoughts and experiences with it so far – particularly since there wasn’t a lot of info available when I ordered it in back in July of 2019.
The Unistellar eVscope is quite different from a traditional optical telescope. It’s a highly integrated and automated digital imaging telescope that enables you to easily find and view deep sky objects in color and detail that would not normally be perceptible to your eye looking through a normal optical telescope. In addition, the eVscope is designed to let you easily participate in and contribute data to crowd-sourced “citizen science” projects.
The eVscope is a 4.5-inch Newtonian reflector that captures light on a highly sensitive, low noise Sony IMX224 color sensor while using a motorized alt-az tracking mount and autonomous field detection to automatically identify, align and continually track its view of the sky. Integrated image-processing software takes and combines an on-going series of short exposures to generate an image in almost real time that brings out much of the very low light, color and detail that’s not visible to the human eye even when looking through a normal telescope. This view accumulates over just seconds and minutes and is displayed both in the telescope’s eyepiece (on an OLED display) as well as on a WiFi-connected smartphone. The whole thing is self-powered via an integrated 9-10 hour rechargeable battery, fits into a large backpack and weighs just under 20 lbs. including the provided tripod.
In other words, it’s quite an impressive level of integration! While you can of course outfit a normal telescope and tracking mount of your choosing with the necessary cameras, computer, tracking and image stacking software, WiFi connectivity, battery power, etc., you then also have to develop the expertise to use and troubleshoot this software – and it’s not trivial. To be clear, the eVscope is not really designed to be a sophisticated imaging tool or to compete with the results you can eventually get with lots of practice and expertise and many hours of capturing and processing images. Instead, the eVscope is intended to let you easily see and enjoy much more detail than you can with a normal, unaided telescope and it provides quick setup, ease of control from your smartphone, and a fun, real time viewing experience all wrapped up in a lovely, convenient little package.
It is however not cheap to integrate all these components into such a convenient package. As such, I wouldn’t recommend it for someone wanting to dip their toe into astronomy on a small budget. It’s pretty clear though that this makes for a wonderful tool for astronomy outreach programs anywhere and I’m really looking forward to sharing the experience with friends and their families.
As I mentioned above, the eVscope is also designed to participate in crowd-sourced “citizen science”, in partnership with the SETI Institute. As per their web site, the eVscope “allows users around the world to participate in observing campaigns to image and collect data on objects of special interest to researchers. In Campaign Mode, image data is automatically sent to a data repository at the SETI Institute’s headquarters in Silicon Valley. The international scientific community can then access unprecedented volumes of image data for specific objects, from thousands of telescopes around the world, at different dates and times. This in turn, can enable new discoveries and enhance our understanding of the universe around us.”
Just in the past week, I had the opportunity to participate in one of these observing sessions. I received an email providing instructions for a particular target and observing time to collect data on an exo-planet transit of “WASP-43b”. The procedure involved setting up beforehand, selecting and confirming the target and then starting the Enhanced Vision capture process and letting it run autonomously for several hours as it tracked the target. Afterwards there was the capturing of 30 seconds of “dark frames” and then initiating the download of data from the telescope followed by the upload to their servers. While I encountered a few issues along the way (included in my bug list below), it was fun to get to participate in a data gathering session like this.
Setup and Use
I recorded a video to demonstrate the ease of setting up and using the eVscope:
I forgot to record using the focus ring on the base of the scope, so perhaps I’ll add that later, but Unistellar provides a nice page detailing how to use it with the provided Bahtinov mask: How to use the Bahtinov mask? (It’s great how the mask is integrated into the cap!)
While I have encountered a lot of bugs (version 0.9), including fairly frequent random crashes (the app quits unexpectedly), the eVscope already provides a fun and amazing experience to share with people. (Presumably they’ll be updating and improving the software over time.) The ease of setup and the speed with which you can get to viewing objects is great. I really like the convenient size of the thing, including the integrated power supply and the optional padded backpack to carry and protect it.
The initial star alignment process is super fast (around 30 seconds) and it’s autonomous field detection system seems to do a great job of tracking the sky and dealing with field rotation over several hours. I do find the views appear slightly soft (presumably from the effort to track, align and integrate frames over many minutes) but still quite enjoyable, and perhaps this will improve with future updates. You can see some sample images below. I should note that I haven’t tried collimating the scope yet, so I’ll update here when I get the chance.
Another aspect of the very quick and easy setup is that it takes less than a minute to pull out the scope on a whim, stand it up on the open patio outside my bedroom, remove the cap, turn it on and dash back inside out of the cold winter night, and settle in with my phone or iPad and mess around exploring the sky, in warmth and comfort. I definitely cannot set up and align my 8” SCT and german equatorial mount so quickly and easily even with the auto-align accessory, plus there’s setting up cameras, laptop, myriad power and USB cables, etc. Not to forget to mention the disassembly and take down time afterwards again!
That said, I don’t think you should think of the eVscope as astrophotography gear. Everything is integrated to make it easy to observe deep sky objects with color and detail you can’t see without the aid of sensors, but it does not provide the means to capture frames and do your own stacking or more sophisticated and detailed imaging with a non-color sensor and color filters, etc. I would not expect this telescope to compete with custom gear where you have control over everything (and of course have to learn how to do everything). That is not the purpose of its design. Similarly, the cost reflects the benefits of integrating all these pieces (sensor, tracking software, stacking/imaging software, display, power supply, etc) into a small and elegant package without any cables or separate components to manage while also making it dead simple to use. That’s what you’re paying for and that’s the trade-off.
The provided documentation is pretty good in some areas but a little weak in others. (As of February 2020.) For example, I was surprised how long it took me to find a little blurb buried in a list at the back of the printed guide that explained how to tell if the battery was fully charged.
And really, the charge state should also be displayed in some form in the app! As of 0.9.3, there is now a rough charge state shown in the app in the form of a battery icon (no percentage estimate though).
Also, what’s going on with the gain/exposure controls only usable in live view and the contrast/brightness controls only usable in enhanced vision mode? Does changing the gain/exposure before starting enhanced vision affect the results? There’s very little information on how best to make use of these controls or how the automatic settings work – in auto mode with enhanced vision, it seems to randomly try different contrast/brightness settings over many minutes. It seems to go back and forth – it doesn’t seem to be working in a particular direction.
Another example is that there’s no explanation (or instructions for use) of the “download data” and “upload data” buttons. I only learned how to use them after getting the email for the “citizen science” observation that included instructions to use those buttons. Still leaves me wondering though as to what that data consists of and whether or not we should be regularly downloading/uploading this data.
However, it does look like Unistellar has been actively adding explanatory content to their online knowledge base over the past couple of months, so more and more questions are getting answered.
Here’s a couple of real time recordings of the Unistellar app showing the live view from the eVscope of the Orion Nebula (over 3.5 minutes) and Bode’s Galaxy (over 6 minutes):
Here are some images illustrating the views you can generate and enjoy in just minutes with the eVscope. I’ve included both screenshots of the full image displayed on my phone as well as the circular cropped image that it produces for display in the eyepiece and that it allows you to save from your phone. (The eyepiece shows only the circular cropped image, it does not display the descriptive text or circular outline.) I have not done any further processing on these images – these are just as they were originally generated by the eVscope app or screenshot-captured off my phone.
I’ll mention right now that I think it’s very annoying that the app does not currently provide an option to save the full, uncropped, undistorted image. The images saved from the app also unfortunately have an “eyepiece lens” effect applied to them. I should not have to go to the trouble of capturing a screenshot of my phone and then manually cropping it to get the full, undistorted image saved as I’ve done for these samples.
Click on any image below to see the full size version and to browse the gallery:
As of February 2020, version 0.9 of the Unistellar app, running on iOS 13:
Currently you see a small constrained view far down the end of a tube. You should really try to shoot for a big gorgeous panoramic view, a “spacewalk vista”, like what you get with TeleVue’s fantastic, wide apparent field eyepieces. Could you simply make use of the same kind of optics and/or display technology inside the electronic viewfinders that Sony and other camera manufacturers use in their digital SLR cameras? These digital display viewfinders do a fantastic job of enlarging the apparent view on these tiny little displays. They’re a joy to use and provide a much larger, clearer, detailed view than you get from the displays mounted on the backs of these same cameras. I realize this would require a hardware change but oh, what a view that would be!
Along these same lines, could there be a way to make use of the full uncropped image in the eyepiece? With relatively large targets, the uncropped view on the phone’s display is much more expansive and enjoyable than the much constrained circular cropped view. Could there be a way to present the full uncropped rectangular view and allow it to be rotated in the eyepiece to deal with changes in the telescope’s orientation?
Issues / Bugs
As of February 2020, these are the issues I’ve been seeing with my current version of the Unistellar app (version 0.9) for iOS 13 (iPhone XS, iPad Pro). I’ve already heard back from Unistellar that many of these issues will be addressed in their upcoming 1.0 release of their software. I’ll strike these out as I find they get addressed: