While from a technical standpoint many of your comments are
accurate, I have to say I disagree with the overall inference that
Tony may have made a poor choice.
Sorry if my post sounded like that, and you should note my comments
at the end. Also number1 i don't wanna get into a ETX flamewar, SAA
have enough of those in the past. Although i do have to say that
ETX is not magic like a lot people make it sound like.
When talking advanced numbers like Strehl ratios, it is unarguable
that the optics you quoted are superior. What is lacking in your
view is a balanced, overall picture of this purchase.
The slightly better optics in those scopes may just make up their
14~10mm less aperature in planetary views compared to a good ETX.
The main advantage I was after are the faster optics and wider
field of view. The wider field of view makes it much suitable for
natural observational use as well. (aka birding)
Because the fact aperature wins the first recommendation for an
astronomical telescope I would gave is actually a 6inch or 8inch
dob, depending on how muncho you are. However if one is unlikely to
learn collimating a newt and/or think a 6inch dob is too big, I
whould then recommend those wide field small refractors (shorttube
80 being the lengendary one in terms of price, but in this case
because Tony want to do photography with CCDs chromatic aberrations
gets mre serious and the fact that newbies LOVE planets, thus the
recommendation of those slightly more upscale one, and yes i could
have suggested a Tak FCL90 or AP)
The scopes you quoted as being superior, yet comparable in price
are really not comparable in price when one considers that 2 out of
the 3 are tube assemblies only.
This brings in the question on how you mount these and ETX. I use
my shortfocal length refractor(70mm) on a regular camera tripod so
i can took it out as fast as it can be. So the mounting for regular
visual use don't cost that much this way.
Now where do you put the ETX while observing??? You can't set it to
the ground unless you are a baby, so people usually put it on a
table/car hood or a tripod. In the case that you use a tripod for
it you end up paying basically for the tube as well, and in each
case you need to find something to hold it.
Now on the case where you do need a good guided mount for deepsky
stuff, here the plastic ETX mount is not good enough for long term
exposures, especially consider the focal length. So given you want
to use the ETX optics you still need that $350~500 for a good mount
and the guiding requirement will be higher than the short focus
stuff. (actually the best bet here are a 300~400 used SP mount
with hopefully wood legs, or if not the CG5 with wooden legs at
about 75 more from telehoon)
Now you think just the 26mm eyepiece is enough for someone??? Even
with an ETX you need more quality eyepieces, and eyepieces under 65
bucks usually performs about the same on F6 or F13.8 as long as you
stay with Pl or Or designs. (now Rini's eyepieces are great values
if you wanna take a chance, although telling him you will be using
it in a fast instrument helps weed out really bad stuff.)
(like ETX the megrez tube have those Pl 25/26mm standard stuff,
also Borgs sales with 2 Pl eyepieces in japan, although i don't
know about how US ones are sold)
So the question here is that given the worst link in an ETX is the
mechanics, did you really save all that much in the long run???
Also I slightly question the fact that ETX comes as ready to go
without the optional tripod.
Also besides Stellaview, the shorttube 80/90/102 are all good deals
but for digicams the trade of chromatic aberration for wide field
may not be worth it, besides they don't take high power that well
for planets.
(for more look at)
http://www.scopereviews.com/page1a.html#8
the F80WA is the same stuff as the shortube 80
The highest quality tube assembly
in the world does a beginner no good if they lack the budget to add
a quality mount and eyepieces.
same with ETX
I'd say one would have to add
another $350 - $500 for a good mount which moves the purchase way
above the range of an ETX. The ETX comes ready to go, with mount
drive and eyepiece and quite good optics for even an advanced
amatuer. As I recall Sky and Telescope reviewed the ETX and
proclaimed it: "The little scope that could". I can't really argue
about the Stellarview - it IS a comparable scope, but, not
necsessarily superior, saying so is a little like saying one should
have bought a Ford instead of a Chevy (or Vice-versa). Comparable,
but different and open to each person's personal tastes.
I'll say Stellarview is VERY different, and personal use and
preference will be the deciding factor on which to pick. And thus
not exactly comparable once a person choose what they want from a
scope. for a person wanna piggyback its stellarvue, but for one
who wants porch planet observing ETX wins hands down.
The fact that it is a long focal length scope isn't necessarily
accurate either. Yes, f/13.8 is long, and yes, f/6 is shorter, but
a 1250mm focal length isn't all that long.
1250mm is pretty long for that mount, and the f ratio is where i
was coming at regarding deepsky photography. Anyway whether
something is long or not is very subjective.
Low power capability is
still quite good with a nearly 1-1/2 degree field of view being
obtainable with inexpensive eyepieces.
which don't hold the M31 well as well as many other star clusters
like M41, Orion's sword, M46+47, M8+M20, etc. Also with that
finderscope, thats not a very big field and another reason why
1250mm is "long". 500mm with 2inch focusers and a $35 Rini 40mm Pl
you get about 3.8 degree of useful field which is actually good
enough for use without a finder + its good for landscape. (even a
regular 32mm 1.25" Pl gets you 3.2 degrees which is very good)
That's the beauty of long
focus scopes, they LOVE just about any eyepiece. And a viewing area
three times the size of a full Moon is nothing to sneeze at. The
real drawback at the lower power end is the lack of a 2" focuser,
but this is a tiny nit not worth picking considering the big
picture.
Long focus scopes also love great mounts, and a good finder. Also
most of the new cheap Pl eyepieces works fine with F6 stuff as
well. The lack of 2" focuser is serious for 35mm photography,
although i throw that out of consideation here. Also for sky
scanning (great way of learning the sky) 9X the moon's field (field
area) is not all that big.
I would also argue against the inference that the ETX's optics are
not up to snuff.
urrr, 80%
85% Strehl is great, consider that any of those 8" SCTs
which gets a 80% would be considered excellent, and 85% or higher a
gem.
All the examples I've looked through gave quite
good images and overall I feel they offer a great package for the
money.
I do agree with these.
Last summer at a large astronomical convention I had just
completed a 2 hour walk of the telescope field doing a "refractor
tour". Most of the refractors on the mountain had been pointed at
Jupiter under excellent seeing conditions. The last scope I looked
through was an 8" AstroPhysics refractor. After ooohing and
ahhhing, I headed back to my scope. On the way back, I noticed
almost hidden between the big scopes, the "tiny" black outline of
an ETX pointing in the direction of Jupiter. I asked the owner for
a look and peered into the eyepiece. There at over 250x was Jupiter
looking good enough for me to exclaim "WOW!" Now remember, I just
walked away from a $20,000+, Strehl-on-steroids 8" AstroPhyics
refractor and was actually MORE blown away by the views in the ETX.
NOT because the ETX showed more - or even as much detail as the big
refractor, but because of what WAS visible in that scope. It was
hard to believe it was a 90mm scope!
Maybe I have looked through too much of those small refractors, but
its image doesn't strikes me as out of the line for a good 90mm
instrument at F13.8.
What it really boils downto is: any scope that tickle's its owner
into further exploration is a great scope.
can't argue with that, and i share the exact same opinion.
and who knows what the
future of astronomy holds for Tony and his daughter. I would
venture to say if he continues, becomes "advanced" and moves on to
a bigger scope, that he should hang onto the ETX for it's
portability, convenience, and "pocket power"
most likely a guiding scope.
which it is great at. I suggested a
short refrac based on those 3 factors as well, and frankly i don't
see ETX as more convenient. (harder to get the view mostly)
I'm coming on kinda strong here in the argument because your
comments ignore Tony's obvious delight with his new scope.
no i didn't, ETX is a wonderful small visual planetary scope, that
is very beautiful. The thing i was pointing out is that for what
he was looking at, it MAY not be the best choice. (also i have seen
ETX being in frustration for newcomers after they get over the
initial planet lust, without the computer control, its not all that
easy to find those dim** fuzzies with an ETX from a starmap
unless you have found those stuff before. [i should know this as i
had to find stuff in a 12" F16 with a 5" F10 finder with only a
1.25 degree of view, and now you should know why i hate those long
focal length stuff, and yeah the planets look awesome in that
finderscope already] Also ETX may not be the best thing for his
photography [newbies should take note that astrophotography isn't
all that easy] wants is my second point.)
Pushing
all numbers and facts aside the only REALLY GOOD scope is the one
that curls its owner's toes!
The only reall good scope is the one that the owner brings out to
take a look everynight, even if it means through cloud openings.
If Tony is being jazzed by the views
his new scope offers, and he thinks it's money well spent, then
none of us should dash that excitement.
completely agree, and i am sorry for that, I was just offering
opinions purely based on optical parameter facts, and instrument's
intended use. I am sorry if they sound negative. Anyways out of the
few quality startscopes out there today ETX have its place for all
the reasons you stated.
Oh... Have you looked off to the right of Jupiter and seen that
ringed planet yet? Simply 3D!
Also right after sunset when the sky is still bright, look west and
there is your Venus, with ETX it should show its phase nicely, and
can be photographed easy with your Oly, even handhold to the
eyepiece.
The 4 easiest nightsky object currently are Moon, Venus, Jupiter,
Saturn, with saturn likely being the most exciting. (also the
reason why you wanna something more than that 48X eyepiece, but
becareful with eyerelief, i would say a barlowed eyepiece around
14mm is good)
Now for something out the solar system.
Orion's Sword under its belt will be the easiest IHMO, with
Pleiades close behind.
The Hyades and Perseus Clusters are easy, but they are better in
binocs.
Beehive in Cancer and Double cluster should be very impressive in
ETX as you pan around.
M31 is the brightest and easiest non-milkyway galaxy in the
northern hemisphere, but it most likely will disappoint you.
Do not TRY M33.
M41 below the Sirus, M35, 37, 36, 38 chain, M46, 47 pair, M48, M93,
NGC 2244, M2, M15 are the other relatively easy and impressive
objectes, you should see in the eyepiece when the autoguider send
you there.
Don't try M1.
Then after you get more used to detecting fuzzies in the early
spring, go for the planetary in M46, and M65,66 double [forget
about NGC 3628 there], M81,82 pair, M51, M94, M63, M101 (this one
if you feel lucky).
Personally I would rate M81, M94 as the easiest 2 after M31.
My advice is, be patient and EXPLORE, EXPLORE, EXPLORE! The WHOLE
universe awaits and it will blow your mind if you look carefully.
My second advice on this will be to buy a nice sky chart like
Uranometria, or Sky Catalog 2000.0. (note you want at least 7th mag
stars and if you have good sky, 9th, so you see whats in the
finder) Of course, any of the free sky atlas software will do as
well, although a paper edition helps in the dark.
Just keep in mind that MOST objects out there are faint fuzzies and
take a careful eye to find and view.
LOL, and a heck a lot practice to find/id them.
DON'T expect the view to be
like the pictures in the magazines or books, just know what you are
seeing is LIVE!!! If you are enjoying the views then that's all
that counts.
Clear and exciting skies.
Exciting as in supernovas and earth missing comets, I hope. There
are enough trash up there already, and i can't seem to escape them
for even half an hour.
Sigh.... A bit too late to the party here.
Well in ETC90 you have a small long focal length instrument. Which
pretty much means that you can only photograph planets and
moon/sun. (yeah meade is a big name for consumer type telescope
and thats why a lot people hears their stuff, and the ETC being
their optically best cheap stuff so whats why many people
recommends it)
However in your case I would rather recommend a high quality small
refractor.
In the days when TMB 80/600 was still cheap (80mm dia. 600mm focal
length) that would be my #1 recommendation for you.
http://www.apm-telescopes.com/products/apm/techspec.htm#Tri_80
(as for how good the optic that is?? look at the Strehl ratio, the
TMB is better than 97% from 500nm and up, while from what i saw ETC
is about 85% on better samples and usually around 80% [local sams
club had a bunch at 395, so i tried out a few of them and if i had
found one that star tested perfect i would have kept it] [Strehl
ratio is how much energy is focused on a star image compare to
perfect optics, so 95%+ is really really good])
the other reason for a small fast and optically excellent refractor
is that, in terms of planetary image a 80mm can be as good as the
ETC, but when you use wider field eyepieces you can watch some
wide nebulas and star clusters nicely. They also make good
spotting scopes for birding and are excellent Telelens for your
camera. ETC is a very restrictive instrument IHMO, and you lost
whats present in a lot small scopes, the wide field. (besides
being fast also means you have some chance at brighter nebulas if
you cool your digicam)
here are what i would recommend today at ETC's price
http://www.apm-telescopes.com/products/apm_specials/borg.htm
the 76mm Borg ED
http://63.169.124.3/product_details.asp?pNumber=2469
Mechanically unbeatable; SD lens; also much better for photo use
than ETC because the 360 degree rotate focuser.
http://www.stellarvue.com/cat4.htm
All 3 types of scope there are good, although the F/9 don't have
nearly as wide a field+slower. Also the cheapest.
anyways thats my take on the ETC price point, it used to be a good
buy, but now lots of its price seems to be on a brand names which
isn't exactly know for optical quality in most of their products.
(but for for being large)
Anyways i am glad to see another new amature astronomer.
)) And
yeah with a small scope and digicam you can make stunning planetary
and lunar images.
