Video summary
The new ZWO Seestar S50 Pro represents a significant evolution in smart telescope technology, combining the advanced features of the S30 Pro line with enhanced optical performance and a larger sensor. Physically, it is the largest and heaviest model released so far, weighing about a pound more than the original S50 due to its upgraded 10 amp-hour battery, which extends runtime to eight to nine hours compared to the four to six hours of previous models. While this increased size makes it slightly less portable than the compact S30 series, it still fits under airline seats and offers ample internal storage with 128 GB of space. A standout improvement is its whisper-quiet operation during tracking, which has been refined to allow for longer 60-second exposures without the high frame rejection rates that plagued earlier models, thereby maximizing data collection throughout a night's observing session.
Optically, the S50 Pro delivers noticeably sharper images than its predecessor, thanks to improved lens elements and better tracking stability. Although the larger sensor results in a wider field of view where celestial objects appear smaller on the screen, cropping into the image reveals that the resolution is effectively identical to the original S50 when viewed at 100% zoom. The video highlights distinct differences in color correction between the two models, with the Pro version exhibiting a slight magenta tint compared to the greenish cast of the older unit, though both are easily manageable in post-processing. For deep sky enthusiasts, the S50 Pro excels in "Stargazing Mode," successfully capturing rich detail on challenging targets like the Iris Nebula and the faint emission lines of Sharpless 132, demonstrating its capability to handle dim objects with impressive sensitivity even over long integration periods.
Beyond optical performance, the Seestar ecosystem is bolstered by partnerships for power solutions, specifically featuring the Blue Edge Elite 100 V2 portable power station for camping trips at dark sky sites. This power station can recharge the S50 Pro up to 20 times and offers versatile output options including AC outlets and DC barrel connectors suitable for other astronomy gear. The review also explores the "Milky Way Mode," which is exclusive to the Pro models, allowing users to freeze foreground elements while blending them seamlessly into wide-angle shots of the galactic core. Additionally, the device supports panoramic stitching for 8K resolution images, although results can vary with atmospheric conditions like moving clouds.
In terms of value and market positioning, the S50 Pro is priced at $899 during pre-order, rising to $999 at retail, placing it between the more portable S30 Pro and discontinued original S50 models. The reviewer concludes that while the S30 Pro remains the superior choice for those prioritizing portability, the S50 Pro stands as the best smart telescope ZWO has produced to date due to its superior tracking, larger sensor, and enhanced optical sharpness. It effectively bridges the gap between consumer-friendly smart scopes and traditional entry-level astrophotography rigs, offering a powerful tool for capturing detailed images of small galaxies and nebulae without requiring extensive manual setup or complex equipment.
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This is the new ZWO Sea Star S50 Pro
smart telescope. And I know from the
comments on my previous videos that many
of you have been [music] eagerly waiting
for the release of this scope because on
paper it seems like the perfect smart
telescope. The reach of the original S50
with all the bells and whistles of the
S30 Pro, including a larger, more
sensitive [music] sensor and improved
optics. But on paper specs are one
thing. In-person testing reveals a lot
more. So, join me as I put this new S50
Pro through its paces and compare it to
the original S50 and the other Sea Star
models in a comprehensive review. My
name is Nico and this is Nebula Photos.
I've had the Sea Star S50 Pro for the
past 2 months, which has given me time
to really get to know it for this
review. ZWO provided me with this
pre-release unit, but they have no say
in what I share in this video. So, let's
jump in. The S50 Pro is the largest and
heaviest Sea Star release so far. It's a
full pound heavier than the original S50
and a bit thicker as well. If you're
thinking about airport travel, the S50
Pro case should work as your under the
seat carry-on. But of course with the
S30 or S30 Pro, I can actually slip the
whole thing in its padded case into my
under the seat bag where I could also
fit in my laptop and other stuff. So the
S30 line is still more portable. In
terms of storage, the S50 Pro matches
the S30 Pro with 128 GB of internal
storage, while the nonpro Stars have
only 64 GB. Something you'll definitely
notice with the S50 Pro if you've used
the previous Sea Stars is that it is the
quietest yet when sloowing and tracking.
It's whisper quiet. I did a little sound
test so you can hear for yourself.
I've not taken apart any of the sea
stars, but I would guess based on it
being quieter that the drive system for
tracking the sky has been improved in
this model. That would also line up with
what I observed in terms of tracking
ability. With every previous Sea Star
model, I was typically okay with 30-se
secondond exposures in EQ mode, but had
issues when I raised that to 60-second
exposures. Not that 60-second exposures
wouldn't work entirely, but just that
the app would reject a lot more frames
due to poor tracking. So, then I usually
just ended up at 30 seconds to get more
data through the night. The S50 Pro's
reject rate with the 60-second exposures
is now very low, at least with the
sample that I've been testing. Here's
some data I collected on that, comparing
it to the original S50.
Another first for the S50 Pro is a
bigger battery. I believe this is the
main reason the Pro is heavier and
thicker than the original S50. All three
previous sears have 6 amp hour
batteries, while the S50 Pro has a 10
amp hour battery. In real world testing,
this means the original sea stars get
you around four to six hours of run
time, while the new S50 Pro will go for
eight to nine hours on one charge. So,
with a battery that lasts that long, I
never had to plug in the S50 Pro during
use when testing it. Um, because we have
short summer nights right now, so it it
always lasted through the whole night.
However, in the middle of the winter
when the nights are longer and the cold
can also shorten uh battery lifespan, it
would probably be a different story. The
other thing to note is at home, it's of
course easy to recharge in between
sessions with the provided USB cable.
But what about when you're out on a
camping trip visiting a dark sky site?
How are you supposed to recharge your
sea star then? Well, that's where Blue
Ediy comes in. Blue Edi is sponsoring
this video and they make a variety of
portable power stations at different
sizes and price points. The one that
they sent out here is the Elite 100 V2
and I've been testing it and it has a
very high capacity. Um, it could
actually recharge this S50 Pro 20 times
over. So, plenty of power even for the
most epic of camping trips. In terms of
power ports for the Sea Star, you're
going to use one of the USB power
outputs. It has two USBA and two USBC.
But the Elite 100 V2 also has four AC
power outputs and two 12volt DC center
pin uh barrel outputs like we often use
with astronomy gear. So plenty of
options and enough power that I can
power plenty of things on my camping
trip. For example, I like freshly ground
coffee when camping. I know that's a
little bougie, but there's nothing
better than really good coffee while out
camping in the middle of nowhere. So, I
think the combination of the Sea Star
and a Blue Eddie portable power station
would be perfect for your next dark sky
trip. And when you do get all set up on
that trip, the first object I'm guessing
many people will observe with their new
S50 Pro is the moon if it's out. It's an
easy thing to do with the Sea Star. And
if we compare the 1x view of the S50 Pro
versus the original S50, it looks like
the original is more magnified. It's
more zoomed in. But that's not actually
an accurate way to put it. The moon is
taking up the same number of pixels
here. It's just that the sensor size on
the S50 Pro is four times larger than
the original S50. We're going from an HD
1080p sensor on the S50 to a 4K sensor
on the S50 Pro. So, that just means
there's more space around the moon and
the moon appears smaller on screen on
the S50 Pro, but you're actually not
losing any actual resolution. If we zoom
both into 100%, you can see the same
amount of detail. Um, it's it's they're
basically identical. And the same thing
plays out for all the solar system
objects. Basically identical resolution.
So here's a comparison on the sun and
now here is Saturn.
So at least in solar system mode,
there's not much of a difference between
what the S50 and the S50 Pro can see.
Milky Way mode, however, is only
available on the Sea Star Pro models.
And it's basically identical between the
S30 Pro and S50 Pro. In both cases, they
use a 4K sensor behind a very wide-angle
lens that allows for a 63° field of
view. You can use it in any part of the
sky. For example, here is the Signis
constellation captured in Milky Way
mode. But something pretty cool it can
do if you're capturing the the core of
the Milky Way is freeze the foreground
and blend it back in seamlessly. I've
noticed this feature has been improving
with each app release, and so it now
lets you spend several minutes on the
foreground, which is nice to reduce
noise. I also tested the Milky Way arch
panorama mode, which can do an 8K
resolution uh by expanding the field of
view, creating a pano image
automatically. It did work here, but it
looks a little bit funky because I was
dealing with moving clouds, but it did
all stitch correctly. I will have a more
detailed look at Sea Star's Milky Way
mode in a video coming out soon, but the
main point I want to make here is that
the Milky Way features on the S50 Pro
are completely identical to the S30 Pro,
and they work quite well. Now, let's
turn to my favorite, deep sky. Um, and
this is what Sea Star calls the
stargazing mode. This is, I think, the
main event of, uh, Sea Star, and the S50
Pro is very impressive. Let's start by
looking at field of view with all four
sea stars on some popular targets. As
you can see here, the S30 Pro has by far
the biggest field of view. The S50 Pro
is next biggest, and it's just a little
bit bigger than the standard S30. And
then the original S50 has the smallest
field of view. I'm using a telescope
simulator here. So, this is uh survey
imagery, not images I took with the sea
star. I just want to show how various
objects fit with each sea star. And the
S30 Pro is still going to be your best
bet for really big objects. Um, of
course, you can use mosaic mode to
expand the smaller FOVs of the sea
stars. It just takes longer. I do think
the S50 Pro uh at just a little bit
bigger than the S30 is a nice middle
ground for field of view for many
different deep sky objects. So, let's
take a look at those. Okay, I want to
start with a little bit of a technical
analysis. So, we're going to be looking
at basically unprocessed data just
stacked. And I have the S50 here on the
left and the S50 Pro on the right. And
this was taken in alt as mode, 500 subs
each. So, uh, equal amounts of
integration. And with this first
comparison, I just wanted to show you
again how the field of view changes
between the S50 and the S50 Pro.
Everything here in black on the S50 is
what we're gaining with the larger
sensor of the S50 Pro. Of course, you
can always crop in on the S50 Pro image
and get just as much detail, if not
more, than you get with the S50.
So, that's the first thing. in terms of
uh signal to noise ratio and and just
you know that kind of thing. I think
maybe we're just getting a little bit
more signal with the improved sensor of
the S50 Pro, but it's not a huge
difference, of course. Okay, now I've
cropped the S50 Pro image into the same
size as the S50 because I just want to
look at image sharpness.
And we'll zoom well in here to really
look at that.
And I think that it's it's clear that
the improved optics, they added an extra
element and I guess improved the optics
just generally with the S50 Pro um has
improved image sharpness and we can see
that through uh the stars, right?
There's a lot of smaller stars here that
are showing in the S50 Pro image that
are sort of blurred out in the S50
image. For instance, this one, this one,
this one. We can just barely see one of
those three in the S50 image, while all
three are quite clear in the S50 Pro
image. And that continues across the
field. Even with larger stars, hopefully
you can see they're a little bit tighter
on the S50 Pro image. But the main thing
that you're going to see is just that
very, very small stars suddenly appear
because it's a sharper telescope. Now,
it could be the optics. It could be the
better tracking on the S50 Pro or it
could be probably a combination of both
the better tracking and the better
optics um that's giving us this sharper
result with the S50 Pro. But I saw this
um throughout my testing. This is of
course in alt as mode with 10-second
exposures, but it was just as pronounced
in EQ mode with 60-second exposures how
much sharper the S50 Pro was uh compared
to the S50. So that's the sharpness
comparison. Okay. Now this is the color
correction comparison. These are both
highly saturated images to show you the
color correction. Basically what I'm
seeing here is that uh the original S50
which is a triplet design is going more
to the green and how it's uh not
perfectly color corrected and the S50
Pro is going more towards the magenta
side. Now both of these it's not a big
issue in processing. You can definitely
deal with this. But this is what we call
chromatic aberration. And the S50, it's
on the green side. On the S50 Pro, it's
on the magenta side. Okay, that's all
I'm going to show in terms of
comparisons between the S50 and the S50
Pro for deep sky objects. Now, I'm just
going to show you my processed results
that I got with the S50 Pro and talk
about these just a little bit. So, this
I think is my favorite image I've ever
taken with a smart scope. Um, it's just
about 6 hours of various exposure
lengths, some 10 seconds, some 30
seconds, some 60 seconds, all combined
together and cropped in on the Iris. And
I don't know, I just think it really
turned out to my liking really well. Um,
there's really nice detail in here on
the center on the the reflection nebula
on Iris. But then as a whole, I just
really like how I was able to bring out
the colorful starfield and this rich
chocolaty uh dark dust all around the
iris. Um, so I just think it turned out
really well and uh the S50 Pro
definitely impressed me with uh what it
could do on a sort of difficult target
like this, the Iris Nebula. Now here's a
less difficult target. This is often,
you know, one of the first of three
targets that people go after along with
Orion and the Pletes. This is, of
course, the Andromeda Galaxy Messier 31,
and I only spent 30 minutes on it. Uh,
which I think for 30 minutes, this is
very impressive. If I tried 30 minutes
with just like a a DSLR unttracked, I
could not reach this kind of result.
It's definitely a very uh nice result.
For just 30 minutes, I was able to bring
out some of the hot blue stars in the
outer arms. Uh, lots of nice detail here
in the core area and the dust lanes. And
overall, I'd be uh pretty happy with
this. I said there would be no more
comparisons, but I Let me show you one
more comparison here. This is not
between the S50 and S50 Pro, but just
between what the S50 Pro creates if you
do no processing. If you just accept the
default stack of 2 hours on the Signis
wall region in the North America Nebula
versus 2 hours that I've processed with
my processing technique of um sort of
accentuating the 03 signal and and and
making more of a color separation. This
was of course done with the light
pollution filter which is unchanged from
previous sea star models. It's a wide uh
band pass dual narrowand filter. I think
it's like 20 and 30 nanometer band
passes or something like that. So they
call it a light pollution filter. You
could also call it a dual narrow band
filter. Okay. And then the last one to
show you here. This is a challenging
object. I wanted to go after one really
challenging narrowand object with the
S50 Pro to see what it could do on
something quite dim. This is Sharpless
132, sometimes called the Lion Nebula in
Sephius. And it's a really interesting
nebula. It has a lot of HA signal, a lot
of 03 signal, but the 03 signal is is
very dim. So, it does take um some
integration to bring it out. This is 13
hours on the Lion Nebula. And if we look
here in the center, it did a good job on
bringing out this 03 river. This is sort
of an interesting little part of it
right here. It also brought out a lot of
background HA, you know, like this. All
this stuff down here is quite dim. And
it it shows how sensitive this this
sensor is that it it was able to do this
much on such a faint emission nebula.
One thing I haven't talked about yet is
price. And the pre-order price for the
S50 Pro is $899.
After pre-order sales end, it will
retail for $9.99. For context, the S30
Pro is $699 and the normal S30 is $3.99.
The original S50 has been discontinued
for a while now, several months, but its
last price before being discontinued was
5.49. Now, if we just look at the Sea
Stars that will be available going
forward, the S30 is obviously the value
model competing with the Dwarf Mini on
the low end with fewer frills, no
secondary camera. The S30 Pro and S50
Pro are both more feature- packed with
the secondary camera, which can do Milky
Way mode, star trails, and other things.
And but the Pro models also have the
bigger more sensitive sensor and that's
going to make a big difference for
stargazing mode especially on the dimmer
deep sky objects that I like like
Nebula. Between the two Pro models, the
main benefit of the S30 Pro is going to
be portability. It's definitely easier
to take everywhere at about half the
size and half the weight. And for me,
the main benefit of the S50 Pro is the
better tracking. But for others, it
might be the increased resolution for
going after smaller objects like small
galaxies. Many things in the Messier
catalog are actually pretty small. In
any case, with each smart telescope
release, I do see them catching up and
getting closer and closer to the results
that I can get with an entry-level
traditional astrophotography rig. So,
I'm curious to see what we will get next
out of the Sea Star line. But I can
confidently say the S50 Pro is the best
Sea Star that ZWO has made to date. So
that's it for this one. Till next time,
this has been Nico Carver wishing
everyone clear skies.