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Actual Q&A from Astro-tom users...
What can I see with a Meade ETX-125?
11/12/2008
Q:
Tom,
Hope you are doing well. I read your article on Meade ETX-125 at http://www.weasner.com/etx/observations/2006/etx-125_obs8.html.
I have had a Meade 125 AT for about 6 months now. I am amazed at
the list of objects that you have been able to view. So far, I have
viewed moon and few planets. I have the eyepiece set (series 4000),
along with Barlow lens. However, the size of the images are very small
even with Barlow. Except for the moon, and Jupiter (could see the red spot and
few Jupiter moons), the size of the other planets (Venus and mars) are very
small. I have tried the high power eyepieces along with Barlow, but the
size is still the same as with 26mm. Am I doing something wrong.
Do you have any advice? Any specific "Barlow + eyepiece"
recommendation for different objects (mars, Venus, satellites and other deep
sky objects). Appreciate any inputs. Thanks Ananth
I am located in Bangalore, India. My neighborhood is dimly
lit. I can easily watch the objects that I aim at. It is a
challenge to watch objects below about 45 degrees from horizon because of the
compound wall and neighborhood lights. Otherwise i am fine.
Altitude/lat/long: 3000 ft. above sea level, Latitudinal Parallels: 12 degree
8' N Longitudinal Meridians: 77 degree 37' E. Obeserver level: I am a
beginner to intermdeidate. I keep a watch of the skymap to discover the
viewable objects. Yes, ETX 125 is the first and the only
telescope. I went for this model because of portability and decent
aperture size Eyepieces: I have the series 4000 Plossl Eyepiece &
Filter Set. It contains the following 6.4mm Super Plossl - 1.25in. 9.7mm
Super Plossl - 1.25in. 12.4mm Super Plossl - 1.25in. 15mm Super Plossl -
1.25in. 32mm Super Plossl - 1.25in. 40mm Super Plossl - 1.25in. #126 2X Barlow
Lens - 1.25in. Color Filter Set #1: #12 Yellow #23A Light Red #58 Green #80A
Blue Moon Filter -1.25in. Hope I can make the best of my telescope with your
inputs.
11/18/2008
A:
Hi
Ananth,
Thanks for the information, it was very helpful. With your setup, you
should be able to see *most* of the Messier Objects pretty well. You
have a good selection of eyepieces, and for the focal length of the ETX-125,
the eyepieces that you will be using the most will be the 32mm, 15 mm and the
9.7mm Plossls. You can view the Double Cluster and M45 the best with the 40
mm. Here are a couple of recommendations.
 | Become good friends with your neighbors and invite them over to look
through your telescope at a few deep sky objects. first because it's a
nice thing to do, and secondly they will quickly see how annoying they're
outdoor lights are to getting a good view and it might make them more
agreeable to turning them off if you ask them later. |
| Get an 1 1/4" O-III filter (Nebula Filter) Get this narrow band
filter from Orion, Meade or Lumicon. It will help on planetary and other
emission nebulae like the Orion Nebula and the Veil Nebula in Cygnus. With
you altitude and seeing conditions, This filter will make a huge
difference to your observing experience. The other filter that I'd
recommend is a variable polarizing Lunar Filter. (about $40 US) but worth
it since you can just dial the polarizing filters in such a way to reduce
the amount of light to a comfortable level. |
| Add an extension onto the end of your scope to block ALL stray light
from coming into the tube. I made mine out of a black closed-cell foam
camping sleeping pad and some velcro. It extends 12 inches out from
the end of my tube when I observe (like a dew shield). Its only 1/8 inch
thick so it's very light. The reduction in stray light has improved my
contrast when observing the dim galaxies of the Coma and Virgo galaxy
clusters. |
| Study the object you are looking for ahead of time in books. After I've
done this, I find that I can see more detail than if I just look through
my eyepiece first. A lot of observational astronomy has to do with
"training" your eyes to see subtle contrast differences. There
were several instances when I was first starting out when I had my
telescope pointed right at an object and couldn't see it because I didn't
really know what I was looking for, and then I'd ask an experienced
observer over to help me locate the object only to hear them chuckle and
tell me that the object was already dead-center in the field of
view. |
| Don't smoke or drink too much coffee on the day of observing. Both
nicotine and caffeine adversely affect your eye's responsiveness. Avoid
looking at the sunset or bright reflections during the period of time
leading up to sunset. Pretend your a pirate and try out the eye patch for
a couple of hours before one observing session and see how much difference
it makes! |
All of these recommendations will definitely improve your view and your
viewing experience. But even with all of these there may be a few of the
Messier objects that you just won't be able to see, for instance M77 and M74
are very difficult. With patience and optimum darkness and seeing conditions
will finally yield results, though just barely. After the Messier list, check
out the Caldwell list and one of the the other "Best Of" autostar
lists fro Dr. Clay Sherrod available online. (Or I can send these to you if
you already have the Meade 505 cable which allows you to update the Autostar
software.) I'm a bit jealous of your Latitude because you get to see some of
the Southern Sky gems that are below my horizon. I had to drag my equipment
down to Australia a few years ago because I wanted to see some of the sky you
get to see! If you ever get to California, please come visit us at our
Club. We have really great people and we'll lend you a scope to use
while you are visiting. Thanks for the question and the later supporting
context... I hope I answered your concerns.
Clear
Skies!
Astro-Tom.com
Update: 11/26/2008
(To Astro-Tom users: If you have not already discovered Michael
Weasner's excellent website that concentrates on the Meade ETX telescope, I'd
like to give you the address: )
http://www.weasner.com/etx/menu.html
Please take a look at Mike's presentation created in July, 2008 about what you
can actually see with the different models of the ETX telescopes.
His eyepiece views in his presentations are fairly close, but I have gotten a
bit higher magnification views with my ETX-125 than he shows. The Moon
is spectacular with the ETX-125 and when I use my 7mm plossl I get sharp,
detailed, Lunar crater views :-)
Please let me know what you think and how your ETX is working out for you.
Clear
Skies!
Astro-Tom.com
What is the Best Telescope for $200
Q:
“I’m
49 and I have less than $200 to spend on amateur astronomy and
I’d like to get the best possible observing experience for my kids and
me. Ideally, I’d like
whatever I get to be portable so I can take it up in the mountains to
look at the stars when we go camping.
Also, it gets really cold in the winter here.
What do you suggest?”
A: Hi,
Knowledge about
where, when and how you plan on using your astronomy equipment helps to
focus in on the right advice for you as an individual observer.
With Winter weather coming, you're going to want something EASY
to bring in and out of the house when the temperatures drop! In my
experience, this requirement should steer you to (1) large binoculars
mounted on a tripod, (2) a Dobsonian telescope of 6 inches to 10 inches
of aperture, (3) a 60-80mm short tube refractor telescope that
you can leave set up on its mount and just carry out, or (4) for about
$200 it is possible to get a good, used, small Schmidt-Cassegrain
electronic telescope like an ETX-90EC. Any of these would be
quality instruments (see brand recommendations below) and will
produce good views of the night sky but with varying amounts of
resolution and light gathering ability. You'll have to hunt for
deals, but I have, at one time or another, owned each one of these
scopes and paid less than $175 for each!
For simplicity, you
may enjoy 10 X 50 binoculars (5mm exit pupil). There are many
options in this range of binoculars.
Check Meade, Celestron, Vixen, Nikon, Canon, and others.
Younger observers have pupils that open up further than 5 mm and
may want the light gathering ability and 6.5 mm exit pupil of a pair of
12 X 80 binoculars. Binoculars
have a fixed amount of magnification.
The first number of "10 X 50" means that they magnify
ten times. The second number means that the big lens on the front
is 50mm across. The bigger
the front lens, the more light they gather and the more $$ you have to
spend to buy them. Another
consideration is that heavy binoculars are hard for kids to hold steady
for any length of time so you may need a tripod.
A telescope has the
benefit of variable its magnification by utilizing different
eyepieces. If a telescope has a focal length of 1000 mm, a 25 mm
eyepiece (standard) will produce a magnification of 1000 divided by 25 =
40 times (40X). Most planetary observation is done at about 90X,
and galaxies/nebulae/star cluster are best seen at 40-50X.
Telescopes produce spectacular narrower-field, higher magnification
views and you can use them for astrophotography, but they aren't as
portable as binoculars. Personally, I own and regularly use both
because they are complimentary. I purchased binoculars first and
learned my way around the constellations and then tackled stellar
details with a telescope, but you can learn the sky either way.
A Dobsonian
telescope is really easy to set up and to use. You just point it
like you would point a cannon, moving it with your hands and look
through the eyepiece. Very simple and straightforward to leave set
up then simply carry the entire setup outside if your back is OK.
Most importantly, “Dob” telescopes will give you the biggest mirror
aperture for the dollar and you'll be able to see the most detail on the
Moon, rings of Saturn, galaxies, nebulae and star clusters.
Remember: “Aperture Rules the
Night” …The more light collected and fed into your eye, the more
you will be able to see. A 10" mirror collecting light is
better than an 8" which is better than a 6" mirror. Good
used brands include Meade, Celestron, Orion, Discovery, and
others. You can even make your own. Ourl astronomy clubs may
sell very good Dobs with a finder scope occasionally at their annual
Picnic.
If you want to take
the scope and head up in the mountains, I’d recommend a used Meade
ETX-80 Backpack Observatory ($299 retail) for maximum portability.
This is a 80mm "Go To" refractor that comes with 9mm and 26 mm
eyepieces, a tripod and a backpack to carry it all in.
The electronic handbox controller allows you to scroll through an
menu of objects, push a button and then the telescope moves itself to
the object automatically. Another option is a Meade ETX-90EC,
which is a 90mm Schmidt-Cassegrain telescope that has more aperture and
much longer focal length for more power to see details. I have
several telescopes, but I frequently use the ETX-125EC which is similar
to the ETX-90EC, but with a larger aperture.
I find that it is very portable and fun to look through.
When there are big events like RTMC, PATS and other
gatherings of amateur astronomers you should go to them and ask around
for a good deal. I'd suggest that you pass out a flyer to people
saying that you're new in astronomy interested in buying one of these
scopes (above) for less than $200 and list your phone number.
Often times with the info that you are brand new in the hobby and have a
great interest in astronomy, one of the old-time amateur astronomers may
have just what you're looking for sitting in a corner and might be
willing to sell it to you at your price.... you never know. I've
gotten a couple of my best scopes just by putting out the word that I
was interested in a certain type of scope and have gotten calls.
Clear
Skies!
Astro-Tom.com
11/2011
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