I had the little beastie out last night at the (semi) dark sky site of Madison Astronomical
Society, Yanna Research Station. FOR ONCE we had clear skies, and quite decent seeing.
I was able to really get into playing with the scope. And thanks to my newly obtained
Thermacell, the bugs were kept at bay very nicely!
The mount was my Celestron CG4. BTW, I'd highly recommend the mount as a great choice
for the AR102; it's like they were made for each other. QUITE stable.
Jupiter, Mars and Saturn were out in their full glory; they were the targets for the evening.
There was also a 12" Dob set up on site.
Jupiter with a 15mm Panoptic (42 power) was pretty decent looking; three moons showing,
and quite perceptible surface detail. Time to start cranking on the power... drag out the
Pretty soon, after some tinkering, the Panoptic was sitting on top of a 3X Barlow
(126 power). BEAUTIFUL views; we had really good seeing. Let's see just how much
we can get away with.
Replace the Panoptic with an 11mm Televue Plossl (172 power). STILL looking VERY
good... let's go for broke; replace the 11mm with an 8mm Televue Plossl (237 power).
We're now well into the realm that's beyond the old Rule of Thumb that says "50 power
per inch of aperture".
The 12" Dob is showing excellent surface detail (VERY good seeing), but we've hit the
limits of the ES; focus is sort of soft now, so we're approaching the point of image
breakup. What we're seeing here is an excellent demonstration of the ancient truth,
Bad point... Jupiter is a VERY bright target, and contrast suffered as a result. A neutral
density filter probably would have brought out more surface detail, but without it
Jupiter's view was STILL quite respectable.
One thing I found impressive... the LACK of chromatic aberration, even with something
I suppose that purists would have found fault here, but by my inexperienced standards,
there was no complaint; quite surprising for a short tube with an air spaced achromat objective.
That assessment could very well be different on a target like the moon, but I don't know
for sure; I packed it in for the night before the moon rose because dewing up was
beginning to become a problem, especially on the Dob.
Shift to Mars next. The Dob was picking out a lot of surface detail; the polar cap was
At lower powers the AR102 showed a cleanly defined ball, with faint surface detail
showing. Jacking up the power to the 200 power range and higher, the detail became
diffuse as image breakdown set in. With color filters it was STILL possible to obtain
halfway decent detail.
Shifting to Saturn... it was Same Song, Different Verse. Not as intensely bright as the
other two, a good image was easily obtainable.
The 12" Dob was seeing quite good cloud detail, and the ring shadow was clearly visible.
The Cassini Division was clearly perceptible, but we were beginning to hit the limit of
The AR102 got a good view, but the ring shadow and Cassini weren't there. Cloud cover
detail was there, but obviously not as good as the Dob was seeing. While not as bright
as Mars and Jupiter, I get the sense that a neutral density filter would have helped on
Overall, my assessment of the ES is still quite positive, but with reservations. It's STILL
an excellent Grab & Go scope, really top notch for the job.
As a planetary scope... it's quite usable, but it's not great, mainly because it won't
gracefully take the power needed for that job.
One characteristic I like... you can get the best out of this telescope with relatively
cheap eyepieces; fancy, high ticket glass won't coax that much more performance out
of it. Give this critter decent Plossls or orthoscopics and it's a happy camper.
Based on last night I made a change to my Grab & Go kit; I've added my Meade
8 - 24mm zoom and a 2X Barlow to the kit. It performs as well as you can expect from
this scope, tho good Plossls would have a slight edge.
In summary... small, pretty light, easy to use, reasonably rugged. Main limitation is that
above 200X you're hitting the limits of performance.
If a fellow Newbie were to ask me what scope to buy, I'd tell him without reservation
that the AR102 is the way to go; it's a scope that you're not going to outgrow quickly,
it's well engineered and built, and the price is outstanding.
IMHO, we have a definite Keeper here.
Edited by Mister T., 03 June 2016 - 03:51 PM.