Today I’ll be reviewing the Phone Skope smartphone adapter for astrophotography using an iPhone XS Max and a Celestron NexStar 8SE telescope. But before we get to the review, I’ll give you a bit of history and colour commentary for my limited background in astrophotography to help inform your understanding of my review.

Getting started with astronomy and dipping my toe in astrophotography waters

I bought my 8SE scope just over five years ago, and my primary interest is and always will be visual observing. I have a small interest in astrophotography, and early on I played with a NexImage 5 webcam just to see if it was something I would cotton to quickly and fall in love. I didn’t. One of the reasons I had chosen the 8SE in the first place with its alt-az mount and goto capabilities was that I hate setup time, I don’t have the patience for an equatorial mount (at least not in my current configuration where I need portability for viewing), and adding in cables, a laptop, etc., to use the Nex5MP was going in the wrong direction. I still have the equipment but haven’t touched it in several years.

I did pick up the T-ring adapter to try attaching my Canon T5i Rebel to the scope, got a few pics, but the mount isn’t really designed for it, and the learning curve is steep. Plus it works best with the laptop and cables attached. Plus a table, chair, shroud for light, dark skies, etc. etc. etc. I tried going the opposite way with an adapter that lets you attach point-and-shoot cameras to the scope, but I found it finicky with the settings and the telescoping lens (if you want to panic, watch the camera start up and start zooming out to find initial focus with the lens getting VERY close to your eyepiece that is mounted just in front of it!). I downloaded Magic Lantern, tried some settings, it all seemed promising, but it wasn’t a “must-have” attachment and activity. I still have lots to learn about observing, so I moved away from it.

Enter the smartphone adapters

I had heard vaguely a few years ago that there was some sort of adapter you could buy that would let you attach your smartphone above your eyepiece, similar to the design for the point-and-shoot camera adapters. Then while attending the Royal Astronomical Society of Canada (RASC) General Assembly here in Ottawa in 2017, the local telescope store had a small table set up with some accessories. And BAM! There was a Meade adapter for the smartphone available for about $30 Cdn and it was an impulse buy. Why not give it a try? After all, I like gadgets.

There are many adapters on the market right now, ranging from $10 no-name models up to $100+ versions. And they all have the same three elements in common:

1. A universal “hold/grip” for the smartphone (aka the platform);
2. A tool to “hold/grip” an eyepiece (aka the clamp); and,
3. Sliding mechanisms to move the smartphone’s camera over the eyepiece (aka alignment tools).

Once all the pieces are assembled, you put your eyepiece in the telescope normally, except it now has a smartphone and adapter attached above it.

The Meade adapter worked “okay” for me, not great, although some of that performance was the poor technique by me and the limitations of my then-current phone. The platform was straightforward enough, open it up left and right, insert phone, close sides to “pinch” it. Easy peasy. The clamp was a round circle with three mounting screws spread evenly around it; you inserted the eyepiece and tightened the three screws by hand to hold it in place. Pretty much the same as you do with a telescope mount for your EP, except three screws instead of one. One limitation, however, is that the clamp was only big enough to hold 1.25″ plossls. Then came the “technique” problem with the centring part. Every smartphone puts the camera in a slightly different place, and so the alignment tools have to let you adjust the location of the platform over the clamp/eyepiece so the camera is aligned with the centre of the EP. Sounds easy, and you can use your smartphone camera in view mode to see when it is centred. The challenge is that on the Meade adapter there were two little sliders – one horizontal and one vertical – that would let you move the camera left and right or forward and back (not height, which is controlled by how deep you place the EP in the clamp). When you got it “right”, you tightened a set screw that would tighten the two directional sliders together like a “T”. All while holding them in the exact centred position below your smartphone and not letting them adjust even a little.

Before you ever take a picture, that combination of elements (platform, clamp, and adjustment tools) can be a bit finicky to accomplish well each time. It takes practice and improvements in your technique over time. Changing smartphones requires completely new adjustments; changing eyepieces in the Meade adapter was relatively fine as the plossls are almost all the same size (they have to be in order to fit!). But the finicky side of alignment was giving me less than stellar outcomes.

It was almost enough to make me want to give up. But by this time I had found Andrew Symes online (@FailedProtostar on Twitter and Canadian Astronomy on WordPress). I have never met him, but Andrew also lives in Ottawa as I do, albeit in a slightly darker suburb than me. And he has the EXACT same scope with stock alt-az mount with which he was producing AMAZING results with a simple adapter and an iPhone. I wondered if it was my alignment challenge that was the limiting factor (it wasn’t, but I didn’t know that at the time).

Upgrading my adapter

The Northeast Astronomy Forum held in 2018 was abuzz with news that Celestron had a brand new adapter called the NexYZ that looked like the Cadillac of adapters. Still designed as a universal adapter for any smartphone, it had made what seemed like significant improvements on all three elements:

1. The platform was larger and would take all the big smartphones;
2. The clamp was now a pincer that could enlarge to even take 2″ eyepieces as well as larger body 1.25″ eyepieces; and,
3. The alignment tools were replaced by three knobs that would allow separate and granular adjustment left and right with one knob, forward and back with another, and up and down with a third.

It looked like a game-changer to me, and despite the $80 Cdn pricetag, I had to have it. I wasn’t looking to create Astronomy Photo of the Day (APOD) outcomes, more just souvenirs of my own viewing. Essentially simple photos for my Astronomy Log to avoid doing sketches (I hate sketching). And since I thought my problem was alignment, the modifications all sounded like huge improvements.

The adapter arrived in early June, and I hoped for immediate success. It didn’t happen. My technique and physical setup had improved, but unfortunately, I was also bumping up against a technological limit I hadn’t realized. I was using a Samsung Note 3 phone, and when I tried to image anything other than the moon, the sensor didn’t seem to want to pull ANY photons in. If I tried a starfield, the camera wouldn’t even snap the photo. It would just stop and say there was nothing to image in the field of view. Sigh.

As I searched around online for others having success, I discovered the truth — my camera API was old, and wouldn’t do more than the basics. But I also noticed something else. Almost everyone who was producing really good results (like Andrew) was using an iOS device (different models) and the software Night Cap. It’s only available as an iOS app, but it works really well. I started wondering if I would upgrade my phone next time to an Apple device. My wife wanted to upgrade at New Year’s and I thought, “Why not?”. So my son inherited my Samsung as a wifi device, and I got the new XS Max.

Night Cap installed? Check. Phone mounted in the adapter? Check. Adjustments made over the eyepieces? Check. Bam! Moon photos, no problem. Adjusted settings, tried to replicate the results of a guy online named Loren Ball who produces images of asteroids with pinpoint starfields. My results were not great, as I still struggled a bit with the alignment over the EP.

Depending on the eyepiece, I was finding it finicky to get the right setup left/right, up/down, and forward/back. Close, but sometimes the EP would also be angled instead of 90 degrees to the phone. Not bad, all within the realm of beginner success, but I tried for some planets and failed spectacularly. Except I knew Andrew Symes had used the SAME setup with a cheaper adapter and had GREAT shots. I wasn’t trying to get his quality, but I was disappointed with some of my results. I doubled-down on testing different components and trying to improve my technique and read voraciously online to see how other people were getting their results.

Have you heard of the Phone Skope adapter?

I was reading one of the few threads on the Cloudy Nights website dealing with smartphone astrophotography and found a post by a new member that mentioned a new type of adapter called the Phone Skope. I’d never heard of it, but I followed the link anyway just to see what was “different”. I confess I didn’t find the initial website photos and videos particularly convincing — there were almost no pics with it attached to an astronomy telescope, just spotting scopes, binoculars and hunting sights on rifles. The gallery had some impressive nature shots, but they could have been taken with a DSLR for all I knew. I couldn’t get the videos to play (in Firefox, the centre button on the video screen wouldn’t play the videos, you have to click in the bottom left-hand corner to start the players!), and even the “buy” site didn’t give me any more info. I was about to ignore it when I noticed that one of the videos was from Youtube, so I clicked over to search for it there, found it, and pressed play.

And my smartphone astrophotography world changed.

The Phone Skope takes a completely different approach to the adapter approach than almost all of the other adapters out there for all three elements:

1. The platform to hold your phone is not a universal mount for all smartphones with pincers to hold your phone, it is a customized mold for YOUR phone. It is sold separately from the eyepiece parts so you can change or upgrade your phone and just replace your phone case. While this also increases your cost (you’re buying a phone case in effect), the benefit is almost hidden. The custom case? It knows EXACTLY where your phone lens is. And the parts join up so that the other parts are PERFECTLY above where YOUR lens is going to be in the case. Game changer!
2. The clamp is what sold me. Instead of a pincer (like the Celestron NexYZ) or a round setting circle with three individual screws to manually adjust (like the Meade), the Phone Skope clamp uses proven technology to ensure your round eyepiece is centred perfectly every time — it uses the same rotating three-point chuck that drills use to hold drill bits. Drills have to have their bits perfectly centred with no margin for vibration, and so they use a three-point chuck where all three pieces come in at the same time when you turn the drill chuck key. The Skope clamp works almost the same way, although the “key” is a small plastic handle that sits overtop the clamp and allows you to rotate it clockwise.
3. The adjustment tools? Completely unneeded. With the phone set in the case + the hole for the camera lens exactly mounted over the clamp + the clamp holding the eyepiece exactly centred, you are guaranteed 100% alignment over the EP every time.

I was in awe. It looked like the perfect adapter. Everything I hated with the other two were “resolved”. The only caveat was that you wouldn’t be able to just take your phone out and let someone else use the adapter with their phone — it is limited to YOUR phone size and shape.

But I don’t share my adapters when I’m imaging, it’s just me. I wanted to buy one immediately. Except I just dumped a whack of cash to replace a bunch of stolen EPs, as well as buying my son a scope. Sigh. And I already own TWO adapters, the Meade and the NexYZ. Double sigh. Oh well, it was a nice fantasy.

But I really wanted to try one

I got to thinking. The smartphone case was $60US; the eyepiece holder was $40US. A little out of my league for a “test” purchase. How could I try one out? How about the same way I try books that I’m not sure if I want to purchase? I’ve been reviewing books for years, and people have sent me copies in exchange for an honest review. Would the company let me borrow one?

Well, I *am* an experienced reviewer and a decent-enough writer that people read my stuff. I have a couple of posts on my site about NexStar alignment issues, and I get a LOT OF hits from astronomy people to those pages each day. Plus I’m active on Facebook forums and Cloudy Nights in the area of smartphone astrophotography while still a newbie, and I have some astro credentials (star party coordinator for the local club plus sit on a board for an astropark). Would that be enough to borrow an adapter?

Apparently it was. I emailed the company, explained my desire to try it even though I already had two other phone adapters, and asked if I could borrow one for an XS Max in exchange for an honest review. They said yes, and I did a little jump for joy. I *really* wanted to try it. Except they’re in Utah and I’m in Ontario, and that meant I had to wait for delivery. Astronomers are NOT good at waiting for astro deliveries, I think it is genetic.

It arrived last week and I immediately had clouds roll in that night. That’s also endemic to the hobby…all astronomy goods are cloud magnets when packed in shipping boxes. But the next night was clear enough to attempt a first light trial.

Getting started – wait, there’s software?

Everyone sells adapters, none of them come with software. I mean, why not use the software on your phone already? Except Phone Skope has a matching iOS and Android app. While it has some basic features, the main reason to use their software is that it allows you to manually switch between camera lenses on your phone if you have more than one (something not all apps do easily). On my XS Max, the cameras are physically located one above the other in the top left hand corner on the back, and the Phone Skope clamp can be slid down or up if desired (for regular or zoom lens). I left it in the up position, so I didn’t need that feature, but the rest of the software was surprisingly decent. The opening setup asks you what you’re pairing it with:

I set it for my phone, and tested the unencumbered phone with it:

The main screen has options for flash, which lens I wanted to use, back or front lens, previous photos, brightness, switching to video, taking the photo, and more detailed settings. There are also sliders to adjust focus, zoom, and brightness. The switching option for video also lets you choose SLO-MO, Time Lapse, 4K Video, and Video Quality, while the general settings had options for Stabilization, Filters, Timer, Watermark, GeoTagging, SAVE AS (format), Photo Quality, and a Features List. I was impressed with the level of detail, but I confess I have little use for the app — I’ll be using Night Cap as it is hands-down the best app on iOS for astrophotography.

Checking out the parts

The guys at Phone Skope sent me the case for my phone (the platform), two different eyepiece holders (the clamp), and a bridge (kind of an adjustment tool of sorts), plus a chuck key, cleaning cloth, and a USB remote (not shown). Here is the set below:

For the case (i.e. the platform), there are five holes — four for slots for the bridge, and one for the camera holes which are perfectly aligned over the camera location on my phone since it is the customized case for the XS Max. Note that you have to remove any phone case you already have in order to use it, and it is designed ONLY for astronomy use (i.e. they don’t recommend leaving it on your phone all the time). For those who have OTTER DEFENDER cases, you can get a custom one that will go over your Otter case. I have Otter, but not the Defender model, so I went with a standard XS Max design.

The back comes with a Phone Skope logo too.

To marry the case to the eyepiece chuck, there is a bridge / joiner. It has four little nubs that fit in the slots and can either be in the top position (centreing over the upper camera) or the down position (centreing over the lower camera). It also has a groove for the chuck to be “turned” / “screwed” into it for stability. Front and back shown below:

The two eyepiece chucks (i.e. the “clamps”) are slightly different sizes to correspond to different sizes of eyepieces, and you can see the three prongs that come out to tighten evenly on the eyepiece and ensure it is centred in the chuck.

The top has two elements — one for the “chuck key” (i.e. a turning handle to slip on) and one for turning “into” the bridge to hold the chuck to the platform.

The plastic handle that turns the above gears is below. I don’t know what to call it — it basically acts like the equivalent of a chuck key, or just a larger “gripper” so you don’t have to turn the chuck by hand.

When you take the bridge and attach it to the case (aka to the platform), you get the following receptacle ready for the chuck and eyepiece to be turned in:

When all is combined (platform, joiner, chuck, and eyepiece), it looks like below. Notice the weight differential — there is almost no weight to the adapter for holding the phone because it is a simple plastic mold to fit the phone. By contrast, the Celestron NexYZ and the Meade adapter both have significant additional metal and plastic that adds weight to the scope when imaging.

Starting the first full test

I connected the first full eyepiece for the test, and decided to start with my lowest power lens, a Celestron 40mm Omni Plossl. I found it simplest to turn the chuck upside down and set the eyepiece down in it vertically before starting to turn (I got it close to start, and then inverted it).

I then married it to the phone case, leaving the phone out of the case for now.

Here is a shot with the chuck and eyepiece mounted on the back and the view through the case’s hole for the camera lens. Perfectly centred, you wouldn’t even know there was anything back there!

With the actual phone in the case, and everything “together”, this was the initial view with the phone.

With the Phone Skope software, it looked like this, just over my tabletop:

But nobody came to see shots of my table, they want shots of exciting things like Jupiter and its moons.

Note that the problem for focus and the circle is not the adapter’s fault. No matter the lighter weight of the case and attachments, I’m still attaching a honking big phone plus an eyepiece. And on my mount, that can cause a bit of tilt/slippage in the image. There are some techniques to fix that, but I didn’t worry about that on first light. With ISO adjusted, and digital zoom, I could tell better it was Jupiter.

Zoomed out, well, still Jupiter but my eye power was a bit low.

So I stepped up the power to a Hyperion 36mm lens.

Notice the gap at the top, i.e. there’s an obvious “hole”…the top of the Hyperion has a bit of a lip on it and the chuck prongs have to either go below it or above it. So it limits how close I can put the lens to the top of the chuck.

Nevertheless, with a bit of digital zoom, you can see Jupiter up close and personal. Until it goes off-screen and I have to zoom back out, recentre, etc. I probably should have aligned the scope. 🙂 The shake is mainly as I was also doing it from my deck that jumps and jiggles if anyone breathes. Like me. Or the neighbour four blocks over.

I also really need to work on focus.

But Jupiter is there.

I don’t have the camera settings perfect, but it’s there.

Really tiny without digital zoom though.

So let’s add more power — up to the Televue Panoptic 27mm.

Again, there’s a gap below the edge, but manageable.

With an itty bitty Jupiter.

More power is just a nudge to a 25mm Plossl which fits in the chuck perfectly. All the Plossls do.

But I got a bit too much gap between the camera lens and the eyepiece, and so I saw this on the screen when trying to focus, etc.

I settled it down, and managed a bit more detail, albeit still with the zoom.

My next power boost is to the 17.3mm Televue Delos. This is my favorite eyepiece for visual, generally, with a huge Field of View and a 117x magnification factor on my scope.

The Delos is a beautiful eyepiece, but notice the slightly tapered body leading up to the lens? That tapering is not a good combination with a three-prong chuck that likes to grab near the top of the EP. I made it work, but it wasn’t the best combo.

Still, I got a bright image.

Again, another small bump in power to 15mm, with another Plossl. They sit in the chucks REALLY well, with lots of shaft left over to go in the eyepiece holder on the scope.

I didn’t do awesome on the settings but that is the technique, not the adapter.

So I boosted again to the 14mm Televue Delos, also with tapering near the top. However, the Delos style DOES have adjustable eye relief, and it will take a bit of practice to get the right combo for it.

One of the moons was trying to photobomb Jupiter, but again, more work needed on stabilizing the mount (not the adapter) and improving my focus and settings.

And finally, it was time for the big gun. Or more like the little gun with all the power. A 9mm plossl.

The setup on the phone showed this as my viewer:

With digital zoom, I could easily find Jupiter.

And Jupiter is great, but everyone wants to see Saturn, right?

And while I’m playing and finishing off, I thought I might as well try for a double star, namely Albireo.

Of course, if I didn’t know and tell you it was Albireo, we wouldn’t know, but it is, trust me. Still need to improve technique. In the meantime, let’s go back to Saturn.

FYI, as an aside, the Phone Skope people also included a USB shutter remote with the package, and it is USB powered as well. I charged it up beforehand, and it worked flawlessly for me. A nice change from a couple of other remotes I have had that die regularly or just kill the battery. Rechargeable is sweet.

Conclusion

The Phone Skope adapter takes a completely different approach to attach smartphones to telescopes with a custom phone case, eyepiece holder, and a bridge to marry the two. Together, the three pieces completely eliminate the guesswork from ensuring the camera lens is exactly centred over your eyepiece. The phone case and attachments are much lighter than conventional adapters, reducing the overall load on your scope, with less impact on stability and alignment. I had some success with every eyepiece combo I tried with it, but more practice may be needed to improve the fit and height setups to fine-tune it a bit more with larger eyepieces. Even the free phone app works well, as does the remote shutter.

On the downside, the custom phone cases mean that the adapter is no longer “universal” for anyone else looking through your scope, but that is an intentional trade-off between universality and guaranteed alignment. I would have liked a small option on one of the chucks to move the prongs up or down to better grasp certain eyepieces (like the Delos) that were tapered, but it wasn’t a significant challenge. I think the only real challenge for most people will be the price. While the reusable chucks/eyepiece holders are on par with medium-range adapters (~$40), the extra separate cost of a customized phone case (~$60) will likely put it above the range of most casual photographers. While I used the larger diameter chuck for a couple of the larger eyepieces to try them, they all worked in the smaller chuck, so you wouldn’t need to buy both unless you were using mostly 2″ eyepieces.

For me, I’ll be sad to return the demo unit when my test is done (I still want to test it with different objects such as the moon and star fields, mostly to see if there are any hidden issues, as well as try improving my technique with the larger EPs). I found the Phone Skope to be a gamechanger for ensuring fast, accurate alignment of the camera lens over the eyepiece, leaving me to focus on finding objects to image and working the camera in my smartphone, rather than fighting the adapter. Even though I already own two other adapters, I might just have to save my nickels and dimes to buy one of these.