Celestron Omni XLT 127 Schmidt-Cassegrain Telescope

The Pleiades

The Pleiades

Celestron Omni XLT 127mm Schmidt-Cassegrain Telescope

One of my new outdoor hobbies is stargazing, and I recently bought a telescope: a Celestron Omni XLT 127mm Schmidt-Cassegrain.

I’ve always enjoyed stargazing, ever since I was a kid, but I’ve only recently taken the time and made the effort to be more serious about it.

I determined last year to get away from things that stress me out (like the constant barrage of bad news) and to focus instead on things that are natural, outdoors, fun, and healthy. Mountain biking, hiking, and stargazing were the first three things that came to mind, as well as quitting smoking, which I did one year ago this month. My mental and physical health has improved a lot!

I did a lot of research before buying my telescope and, like anything else, trade-offs were made. I decided to get the Schmidt-Cassegrain type because it seems like the best overall type of telescope for backyard astronomy.

I wanted something for a beginner or intermediate user… not something I wasn’t yet ready for and couldn’t fully use the potential of… and I wanted something that was easily portable. Plus, I didn’t want a computer controlled scope and mount, because I wanted to find objects on my own, using an equatorial mount.

It’s hard to find a telescope these days that isn’t computer controlled and when I found the Omni series by Celestron I knew I had found what I wanted: A high quality, affordable telescope, with a sturdy equatorial mount, that wasn’t computer controlled.

As I said, trade-offs had to be made. I wanted something that was easily portable, so I was happy with the Celestron Omni XLT 127 (=5 inches). An 8 inch scope would have been nicer, but it also would have been more expensive and heavier, and since the Omni series only has a 5 inch Schmidt-Cassegrain telescope (SCT) a 5 inch SCT is what I got.

The 5 inch SCT will allow me to see how much stargazing I do over the next year, and, if I stick with it, I can think about buying a more expensive 8 inch telescope next year.

The optics of my Omni XLT 127 are really great and I’ve been very happy with my purchase. It’s a quality telescope and mount that’s easily portable and I’m enjoying it very much every chance I get! 😀

I’m planning on taking it to a nearby dark sky location this spring and summer: Cherry Springs Dark Sky Park.

Below are some of the links I found during my research. There’s not a lot of information out there about this telescope, but there is some. There’s also a link below for the binoculars I bought, too:

Celestron Omni XLT 127 Schmidt-Cassegrain Telescope

Celestron Omni XLT 127 Schmidt-Cassegrain Telescope

Celestron Omni XLT 127mm Schmidt-Cassegrain Telescope

High-quality optics meet elegant design in the Omni XLT series. With three optical tube styles, the Omni XLT series has a setup to suit the needs of every amateur astronomer.

Our proprietary StarBright XLT optical coatings maximize light transmission and reduce internal reflections for the brightest possible images. The CG-4 German equatorial mount helps you navigate the night sky quickly and track objects smoothly.

High quality optics start with each lens and(or) mirror being hand selected so only the finest grade of optical glass is used

StarBright XLT coatings provide maximized light transmission

25 mm multi-coated eyepiece – 20 mm eye relief, 50° FOV

1.25″ star diagonal

CG-4 German Equatorial mount with setting circles and slow motion controls – to accurately locate and track sky objects

Ball bearings in both axis of the mount for smooth performance

Heavy-duty pre-assembled stainless steel tripod featuring 1.75″ legs, accessory tray and bubble level

Easy no-tool setup

Celestron Omni XLT 127 Focal Length, Ratio, and Magnification

Magnification Formula: Focal Length Divided By Eyepiece Focal Length 

Celestron Omni XLT 127 Focal Length = 1250mm

Focal Ratio: Focal Length Divided by Aperture

Celestron Omni XLT 127 = 1250 divided by 127 = 9.8 

Celestron Omni XLT 127 Lowest Magnification = 18x

Celestron Omni XLT 127 Highest Magnification = 300 x

Celestron Omni XLT 127 Schmidt-Cassegrain Telescope

Omni XLT 127 Telescope (#11084) ($729.94) – http://www.celestron.com/browse-shop/astronomy/telescopes/omni-xlt-127-telescope

Omni XLT 127 Telescope (#11084) ($569.95) (Free Shipping & No Tax) – http://www.amazon.com/Celestron-11084-Omni-XLT-127/dp/B000NIKQ4E

Dual axis motor drive and polar finder scope are available but not included

Celestron 93522 Dual Axis Motor Drive (CG4) ($107.80) – http://www.amazon.com/Celestron-93522-Motor-Drive-Advanced/dp/B0000C3WBB

Celestron Polar Finder Scope for CG-4 (Omni) 94223 ($40.56) – http://www.amazon.com/Celestron-Polar-Finder-CG-4-94223/dp/B001TIE1D4


Hard copies of the manual are included with the telescope and mount

Celestron Omni XLT manual (.pdf) – https://www.astronomics.com/documents/celestron/celestron%20omni%20xlt%20manual.pdf


Review: Celestron Omni XLT 127 – http://www.skyatnightmagazine.com/review/telescopes/celestron-omni-xlt-127

Review: Celestron Omni 127 – http://www.cloudynights.com/page/articles/cat/user-reviews/telescopes/schmidt-cassegrains-scts/celestron-omni-127-r1868 

Astronomy Magazine Equipment Review: Celestron revives a classic scope: With the Omni XLT 127, Celestron has made its signature 5-inch scope even better (.pdf) – http://www.astronomy.com/~/media/import/files/pdf/9/b/5/1209_celestron_omni_xlt_127.pdf


One 25mm eyepiece is included. Additional are available from Celestron.

Celestron 1.25″ Telescope Eyepiece and Filter Accessory Kit – http://www.telescope.com/Accessories/Telescope-Eyepieces/Celestron-125-Telescope-Eyepiece-and-Filter-Accessory-Kit/pc/-1/c/3/sc/47/p/5631.uts

Dew Shield

AstroZap Flexible Telescope Dew Shields, Celestron 5 in. SE – http://www.amazon.com/gp/product/B006RJPXYG/


How to Start Right in Backyard Astronomy | Sky & Telescope – http://shar.es/1bTTU5

Celestron Omni XLT 127 Schmidt-Cassegrain Telescope

Celestron Omni XLT 127 Schmidt-Cassegrain Telescope


Dr. Jason Lisle | Astronomy Reveals Creation: http://youtu.be/hzzARVIYiwY

Top 20 Astronomy Tips: http://youtu.be/UPoh76f60kA

Black Forest Star Party–Dark Skies: http://youtu.be/q3uVUZloXrw

EQ Mount Alignment, Polar Scopes & More: http://youtu.be/XwJ9O0lFnQs

Setting Up a German Equatorial Mount: http://youtu.be/TdkB5NCnFps

How to Align an Equatorial Mount: http://youtu.be/plx6XXDgf2E

How to use an equatorial mount for amateur telescopes: http://youtu.be/F7HVDKAZ6eM

CG-4 EQ Mount & Celestial Coordinates

My Location: Mont Alto, Pennsylvania – 39° 50′ 39″ N / 77° 33′ 30″ W


How do I use the RA Vernier scales on my Omni XLT (CG-4) mount’s setting circles?


The RA setting circle on your CG-4 mount is only marked to intervals of ten minutes. To increase the accuracy of the circle, there is a Vernier scale that allows you to get more precise readings (down to one minute of right ascension).

To use the RA Vernier, note that the zero (0) mark on the right-hand side is the same as the RA indicator. Numbers on the scale increase to the left.

If the RA indicator is right on one of the marks of the RA setting circle, that is the RA coordinate where the telescope is pointing. What if the indicator is between two of the marks on the RA setting circle? In this case, one of the marks on the Vernier will line up with one of the marks on the setting circle. This mark on the Vernier is the number of minutes that should be added to the RA reading of the indicator. Since the indicator is between two RA marks, add the minutes to the lower value that the RA indicator falls between.

For example, if the RA indicator is just left of the 5h 40m mark, then the RA value is between 5h 40m and 5h 50m. If you look down the Vernier scale, you will see only one mark is in line with a division mark on the RA setting circle. Let’s say that the “4” is the only mark to line up with any of the marks on the RA setting circle. This means that you are 4 minutes to the left of the 5h 40m mark or more simply at 5h 44m.

Here’s how to use your Vernier when observing:

Look up the coordinates of the object you want to observe. If you want to see the Orion Nebula (M42), then it’s at 5h 35m right ascension (RA) and -05 degrees 27 minutes declination (Dec).

Release the RA clamp and rotate the telescope until the RA indicator is between the 5h 30m mark and the 5h 40m mark on the RA setting circle. Lock the RA clamp to hold the telescope in place. Move the telescope in RA until the five on the Vernier scale lines up with one of the marks on the RA setting circle. Remember, the RA indicator must stay between the 5h 30m mark and the 5h 40m mark on the RA setting circle!

Set the declination directly by estimating between the marks at every two degrees on the Dec circles.

Look through the telescope and the Orion Nebula should be within the field of view if you are using a low-power eyepiece. 

Source: How do I use the RA Vernier scales on my Omni XLT (CG-4) mount’s setting circles? – http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=2248

Astronomy Basics (.pdf) – http://www.celestron.com/c3/images/files/downloads/1297798410_astronomybasics.pdf

Celestial Observing (.pdf) – http://www.celestron.com/c3/images/files/downloads/1297801590_celestialobserv.pdf

Telescope Basics (.pdf) – http://www.celestron.com/c3/images/files/downloads/1297801757_telescopebasics.pdf

Telescope Maintenance (.pdf) – http://www.celestron.com/c3/images/files/downloads/1297801919_telescopemainte.pdf

Celestial Coordinates – http://www.telescope.com/Getting-Started/Stargazing-Basics/Celestial-Coordinates/pc/-1/c/460/sc/461/p/99817.uts


Stellarium: http://stellarium.org/  Stellarium is the best and it’s free! 😀

Stellarium User Guide: http://stellarium.org/wiki/index.php/Stellarium_User_Guide


SCT Scopes – http://sctscopes.net/

Celestron: http://www.celestron.com/

Orion: http://www.telescope.com/  Orion $10 Off $100 or more purchase code: PS0214


EarthSky – http://earthsky.org/ (subscribe for daily emails!)

Sky & Telescope: http://www.skyandtelescope.com/

Free Star Charts: http://freestarcharts.com/

My friend George Varros’ website – http://www.gvarros.com/index.html (George is so smart!)

TriState Astronomers

We began in 1985 and we enjoy sharing the ageless wonders of the night sky. If you have ever watched the stars at night and wondered about them, then you might like to join us. We meet on the third Wednesday of the month, September to May, at the William M. Brish Planetarium in Hagerstown, MD. at 7:30 p.m. EST. Guests are always welcome! We have a monthly newsletter called The Observer. We have star parties on the weekends nearest the new moon when the sky is dark.

TriState Astronomers: http://www.tristateastronomers.org/

Deep Astronomy: http://www.deepastronomy.com/

Eyes on the Sky: http://eyesonthesky.com/

7 of the best places to see the Milky Way – GrindTV.com: http://www.grindtv.com/lifestyle/pro-active/post/places-to-see-the-milky-way/#.VNWfwqSXDwQ.twitter


Sky & Telescope’s Pocket Sky Atlas ($16.04) – http://www.amazon.com/gp/product/1931559317 

Sky & Telescope’s Binocular Highlights ($21.95) – http://www.shopatsky.com/binocular-highlights

The Stargazer’s Guide to the Night Sky ($25.82) – http://www.amazon.com/gp/product/0890516413  (I love this book!)

NightWatch: A Practical Guide to Viewing the Universe ($31.50) – http://www.amazon.com/NightWatch-Practical-Guide-Viewing-Universe/dp/155407147X

Check out The 13 Most Beautiful Stargazing Spots in America

#2 is Cherry Springs State Park (Pennsylvania)

“Oh, Cherry Springs State Park, your views never cease to amaze. The Milky Way glows brighter than ever from the darkest regions of this park, which is arguably the most impressive of all the dark sky regions within the country. While there, you can see more stars and other celestial bodies than almost anywhere else in the country with the naked eye.”

Check out The 13 Most Beautiful Stargazing Spots in America:  http://imp.lc/ty/b/12808

Cherry Springs State Park

“Cherry Springs State Park is nearly as remote and wild today as it was two centuries ago. Its dark skies make it a haven for astronomers. Named for the large stands of black cherry trees in the park, the 82-acre state park is surrounded by the 262,000-acre Susquehannock State Forest. The Susquehannock Trail passes nearby and offers 85 miles of backpacking and hiking.”

Cherry Springs State Park – http://www.dcnr.state.pa.us/stateparks/findapark/cherrysprings/

Short term stargazing at Cherry Springs: http://www.dcnr.state.pa.us/stateparks/findapark/cherrysprings/index.htm

Long term stargazing at Cherry Springs: http://www.dcnr.state.pa.us/stateparks/findapark/cherrysprings/serious-stargazing/index.htm

Cherry Springs Dark Sky Fund: http://www.csspdarkskyfund.org/home/index

The Dark Skies of Cherry Springs State Park

The Dark Skies of Cherry Springs State Park – http://www.dcnr.state.pa.us/stateparks/findapark/cherrysprings/cherrysprings-darkskies/index.htm

Cherry Springs Clear Sky Chart – http://cleardarksky.com/c/ChrSprPkPAkey.html

INTERNATIONAL DARK SKY PARKS – http://www.darksky.org/international-dark-sky-places/about-ids-places/parks

IDA: http://www.darksky.org/about-us

The Cherry Springs Star Party (June 11-14 2015): http://www.astrohbg.org/

Black Forest Star Party at Cherry Springs: http://bfsp.org/

BFSP 2015 will be September 11-13, 2015.  Registration will open in the spring.

Black Forest Star Party–Dark Skies: http://youtu.be/q3uVUZloXrw

PA State Park Online Reservations

If you want to explore Pennsylvania’s great outdoors, you’ve come to the right place. You can find information for planning a one day picnic or hiking trip, a weekend getaway, or a vacation. Pennsylvania State Parks do not charge an entrance fee.

Make online reservations or call toll-free 888-PA-PARKS (888-727-2757), 7 a.m. to 5 p.m. Monday to Saturday, for state park information and reservations, or e-mail us your postal address for an information packet.


Orion has a good selection of quality binoculars. I have the Orion Giant View 15×70 binoculars. They weigh about four pounds and I prefer using these without a tripod. They’re great for scanning the night sky! Most stargazers suggest something with less magnification than 15x because the increased magnification makes it hard to steady the image, which makes things kind of jumpy. My 15x70s are hard to steady for this reason but the images are really great nonetheless. As I said, I use them to scan the sky and locate objects, and the images aren’t all that jumpy while scanning… only while trying to hold the image still. I really like that the Giant View 15x70s have individual eyepiece focusing, and this was one of the reasons I bought them. Once I focused the eyepieces I’ve never needed to focus them again. They stay put. I like that the Giant View 15x70s came with a hard case, too. Makes them great for traveling! The optics of my 15x70s are great, the light gathering power is awesome, and my views of the night sky with them are quite spectacular! My favorite object to view with these is The Pleiades! 😀

Orion Giant View 15×70 Astronomy Binoculars

Orion Giant View 15x70 w/case

Orion Giant View 15×70 w/case

Portable yet powerful, these binoculars feature 70mm objective lenses and 15x power magnification

BAK-4 prisms and fully multi-coated optics ensure great light transmission and contrast

Individual binocular eyepiece focusing for enhanced accuracy

We recommend using a tripod for extended viewing, attachment to tripod requires L-adapter and field tripod or binocular mount (all sold separately)

Includes heavy-duty hard carry case, dust caps, and more

Giant View 15×70 Astronomy Binoculars | Orion Telescopes & Binoculars ($236.89) – http://www.telescope.com/Binoculars/Astronomy-Binoculars/Orion-Giant-View-15×70-Astronomy-Binoculars/c/5/sc/72/p/9327.uts

Orion Giant View 15x70 Specs

Orion Giant View 15×70 Specs

About ajmacdonaldjr

writer, author, blogger
This entry was posted in Astronomy, Hobbies and tagged , , , , , , . Bookmark the permalink.

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