Telescope Reviews: First Light - C11SGT on CG-5 mount

Hi all,

Well as promised here's my report on the Celestron C11SGT Advanced Series telescope on the much debated CG-5A mount.

DISCLAIMER: First things first; I'm a newbie. While I've been into astronomy for years and have used several telescopes in the past, my experience is somewhat limited and I have not been active in star-gazing for several years. I'm a bit rusty and am prone to mistakes that a typical newbie would make.

BACKGROUND: With my rekindling of interest in astronomy, I realized that my 4" Astroscan was not going to cut it. I really wanted more aperature and a scope with at least basic tracking capabilities. The GOTO scopes sounded nice and GPS seemed rather "cool" too but, not necessary.
I orginally, focused on 12" or so dobsonians like the Orion XT-12.5 or Discoveries. The price for the amount of aperature was very tempting. But, I kept coming back to having some kind of tracking. I realize it's not hard to keep objects in view but, I really feel this is feature that greatly enhances viewing especially with moderate or high magnification. I discovered that they made tracking mounts for Dobsonians. Great I thought! However, unless you build one yourself, it appears that the purchase of one bumps your "most aperature for the buck" dobsonian into SCT territory.

Serendipity struck when I saw the ads for the new Celestron C11SGT Advanced Series telescopes. This scope seemed a bargain for the aperature and had all the features I wanted plus more. What was the catch? A little more research suggested that the mount might not be adequate for the heft of the C11 OTA. Some people suggested that it would be terrible for casual viewing and unthinkable for astrophotography. Others felt that Celestron wouldn't dare put out a scope with a sub-par mount (even at this price point) and that the scope should be fine for visual viewing and maybe descent for astrophotography.
A call to Celestron revealed their spin (o.k., the technician's opinion I spoke with.). Celestron's view is that the mount is more than sufficient for the C11 OTA for visual viewing. The OTA weighs 27.5 lbs. and the CG-5A is rated for 35 lbs. With regards to astrophotography, the technician went onto say that as long as you didn't exceed the mounts limits (or marginally so...), you "should" be satisfied with the results.

I've no immediate plans for astrophotography. Would it be nice to have the capabilities? Sure! But, as the cliche goes, "There's no free lunch." It seems that a sturdier mount would dictate a heavier mount. The C11 is already in the minds of many, getting border-line at portability. Celestron's CGE mounted C11 appears robust enough for astrophotography but it weighs abit more and cost significant more then it's Advanced Series sibling.

It's very tempting to buy more scope than you need. However, Astromart, E-bay, and other markets are littered with scopes that were under utilized by over zealoust buyers (especially newbies with "hubble-like asperations".). Numerous telescope buyer-guides caution against this "candy store malady" for the newbie, especially with regards to photography and the first scope. I decided to follow their recommendations and not necessarily make my next scope purchase contigent on it's ability for astrophotography since it was not an immediate goal.

Whew!! O.k., enough already of the back ground let's get onto the scope review.

EQUIPMENT: C11SGT with Starbright coating (XLT) on CG-5A mount, of course. Eyepieces: 40mm Celestron E-Lux (included with scope), Edmund Scientifica RKE 28mm (came with trusty AstroScan, my first telescope.),Meade Series 4000 9.7mm Super Plossl, and a Meade 2X Barlow. Powersupply: Celestron PowerTank 17.

CONDITIONS: Located at Woodward Resevoir. A resevoir in CA outside of Oakdale CA. Seeing conditions were terrible with the full (or nearly full) moon out. The milky way was not visible and naked-eye visible DSOs (M31-Andromeda Galaxy, M31 globular cluster,etc.) were invisible to the naked-eye. Light pollution from near-by cities (Oakdale, Escalon, and Modesto) were mostly confined to the horizon but, it wouldn't have mattered as the full moon was easily casting shadows on the ground. Atmosphere was however, stable.

SETTING UP: I've set this scope up now about 5 times. To me, it's a very fine balance of reasonably large aperature and portability. I'm 5'10" and 185 lbs. While I won't be putting CA's Gov. Arnold to shame anytime soon, I'm in good shape and fairly active. I found myself setting this scope up in about 15 minutes. The C11 OTA comes with a handle on the base that makes for easy grasping. My basic setup routine includes pulling out the CG-5A tripod out of the car, and placing it in the spot I've chosen. Installing the leg reinforcement brace. Retrieving the weight bar and 3 11lbs. weights and installing them to the mount. Grab the C11 OTA by the handle and installing it on the mount. All of these components are easily transported by myself. I wouldn't want to have to travel more than about 50 yards or so with any one component from the car, however.
Assembling all the above mentioned parts is straight forward. The most awkward part being the mounting of the OTA onto the CG-5A mount. I accomplish this by lifting the OTA by the handle and the front of the tube with my other hand. After I've guided the dove tail into the bracket on the mount, I can hold the OTA stable enough by the handle with one hand and use the other to tighten the setting screw. I'm always cautious to assure the OTA is properly mounted before balancing the OTA with the included weights. Most times, I've one hand ready while rotating the assembly along one axis or the other during the balance routine. So far, the scope has alway solidly mounted with no slippage.
BTW, I've found that I use all 3 11lbs. weights for balancing. One weight is near the top of the support bar, on at the bottom, and the third is located roughly an inch above the bottom weight. I've found this spacing balances my scope nicely, with just a hint of bias towards the weights as Celestron recommends.

After the assembly, I hook up my power source. You can use the included cigarette lighter adaptor with it's cable spanning some 25' or so and plug into an accesary port in your vehicle or use a portable power supply. I just purchased the Celestron PowerTank17 and used it for this report. BTW, the PowerTank17 works great and is not as heavy as it appears. It includes an extremely powerfull white light and a removable red light anchored to the unit via a manually retractable cable. The power supply includes various power-output ports including two cigarette-lighter/accesary ports. Running the scope for 4 hours (slewing this way and that, merrily) with the red-light on constantly barely put a dent in this monsters capacity.

IN SEARCH OF ALIGNMENT: The next step is to align the scope. I've very limited experience with aligning scopes as my AstroScan was self aligning

. Additionally, I've nevered used a GOTO scope before. So, for the most part this is all new to me. I knew this process might be daunting for the unintiated so I prepared myself for the unthinkable and actually read the manual. My first several attempts at aligning the scope were abismal. I realized my methodology might be lacking when derectives to the computer to find the moon were off by about 30 degrees. Not good for finding DSOs

Much of the problem was that where I originally tested this feature out was in front of my house. Located here, much of the sky is blocked. O.k. it didn't help that I mis-identified Polaris

Fast forward to last night. By this time I'd finally gotten reasonble alignments after coming across a helpful hint on the web (BTW, it is documented in the manaul). That hint is to alway finish the centering of your alignment star with the "UP" and "Right" arrows on the hand-controller. It seems this process will greatly eliminate any slack/backlash in the gear assembly of the motor. I tried this process last night and was very pleased with the results (more on that later.).
The computerized component of the alignment process gives you three choices; Auto, Three Star Align, and Quick Align. With "Auto", after you put in your specific location cordinates, date and time, the computer will pick three stars for you to align on. You can skip a selected star and force the computer to supply an alternate. You might want to do this because the computer selected star is obstructed by a tree, building or whatever. The "Three Star" align requires you to tell which three stars to align on and finally the "Quick Align" is really just telling the computer you've manually done a polar alignment and want no intervention from the computer (note: the GOTO function will not work with the "Quick-Align" method.)

I personally found the easiest and most reliable method to be the "Auto-Align" method. Maybe with experience this will change but, for now I've had my most success with it.

Besides identifing stars properly

the most difficult part of the alignment process is actually centering the star in the field of view especially in the 9X50 finder scope. The finder is attached via a bracket and the finder itself can be aligned via three set screws. Getting the finder and the scope centered on the same object can be bit tricky as those three screws are awkward to master and the finder scope's eye piece is rather small in my opinion. I found myself all to often scrunched up against the back of the scope with face contorted trying to get a good view in the finder. It's all doable mind you, it just takes patience and bit of fiddling with, at least in my unexperienced hands. Once the star is viewable in the scope's eye-piece things get much better. Fine adjustments with the hand controller are very easy. Slewing speed can be controlled "on-the-fly". Pushing the desired directional arrow button sets you off in that direction. However, if while holding the button down you depress the opposite arrow, the speed picks up in the direction you've selected. It's kind of like a "turbo" button. Maybe this is a common feature but, it's new to me and I found it very useful.

I would strongly recommend following the "finish with the UP and RIGHT arrow" concept. I don't know if I've just gotton better with aligments. What I do know is that the first time I employed this method my resultent GOTO's were always within the FOV of my 40mm eyepiece.

THE VIEWS, FINALLY: All right down to the meat. No more disclaimers, no more rationalizations. I was extremely impressed with the views this scope supplied. The seeing conditions were lousy, my EP's are average at best and yet I saw more things last night than in all the my active days of star-gazing combined. True, many of the objects I viewed last night that I've seen before did not "knock me out". They didn't impress me necessarily because of how they presented themselves but, because I could see them at all or the amount of detail visible despite the conditions. This coupled with the number of new objects I saw last night had me grinning and muttering under my breath.

A quick run down of objects:

M13; This famous globular cluster was easily visible with my 40mm EP. Contrast washed out by full moon but individuals stars easily seen resolved to the core. Popping on the 2X Barlow made M13 bigger with even less contrast but not much lost in details.

M31: Easily visible but fuzzy and faded. Not the scopes fault as I've seen more details on M31 with my Astroscan under dark skies.

Ring Nebula: Last night was the first time I've veiwed this object through a telescope. Ring easily decernable in my 40mm EP albeit small. I just stared at it in awe for several minutes. Don't know how difficult this object is to view but, it was my first time and I was enchanted. The 2X barlow enlarged the object with some sacrafice of detail but still decernable as a ring.

Blue Nebule?: At one point last night I allowed the "Touring" feature to slew the scope to "popular" objects in it's database. I'm sure I'm misidentifing the name of this object but, it was something like "Blue Nebule". Anyway, it is a sperical planetary nebule. I've never seen it before. With the 40mm it was small but plainly visisble as disk or sphere with a blue green color. Beating it with the 2X barlow fuzzed it up but, it was still decernable as a distinct sphere. Cool!

M51: Galaxy near Ursa Major. Just decernable with averted vision.

Open clusters, Globular clusters, double Clusters; oh my!:

I can't recall all the clusters I saw. Trust me, it was much more than just M13 in Hercules. All the globs I could see showed details often down to the core. All somewhat faded or washed out. The open clusters faired better in contrast. The Double Cluster near Cassiopeia was easy pickings.

The Moon, so bright I shoulda' worn shades: Very nice details in the 40mm. 2X Barlow buddy made it bigger and better. Strapping on the 28mm RKE Edmonds Scientifica was really impressive. With this combo we're right at 200X magnification. Still very crisp,detailed, and BIG. The Meade 9.7 mm didn't perform as well. Even sans the barlow, this EP didn't seem as detailed as the Astro/Barlow combo. Not bad, just not as good. Adding the barlow definetly reduced brighness and introduced a fair amount of detail lose. Not sure if this EP's is dirty or were reaching the limit of the scope. With the Barlow I think we're around 560X magnification.

GO GO GOTO: There has been much debate on the value of GOTO scopes. Some folks fear that it will make lazy blathering idiots out newbies who will never grow up to be real "star-hoppers". Others, view them for there convenince and aid in eliminating frustration with regards to getting lost in the "celestrial woods".
I align myself with the latter school of thought. I loved it. I was able to see many more objects than I would have without it. I spent much more time viewing and under the enchanting spell of awe as I gazed at DSOs as compared to manually try to find them all the while muttering to myself "where the heck is it!". Too, I did not find myself not wanting to know where the newly found treasure was in sky with the naked eye. All views were preceeded or followed by careful study of a star map and naked eye orientation.

As mentioned earlier. All my GOTO's put the object within the field of view of the 40mm eye-piece. Not neseccesarily dead center, but with the FOV and easy enough to center with the directional buttons. After awhile, I began to trust the GOTO so much so, that if I didn't see a selected object, I assumed it was due to the seeing conditions or it was beyond the limits of my C11 ( many of the objects I selected were unknown to me so I didn't know what equipment would be needed to reasonably see them.).

STA STA STABILITY: Very nice. I had no problems viewing objects and vibrations due to focus adjustments dampered out after a second or two. Even viewing with moderately high magnification was well within my tolerance. I will say that for photography however, you might want to consider a different mount. I think Celestron's claim, mentioned earlier, with regards to this mount is spot on. Great for viewing and marginal for photography.

As the evening wore on, the winds began to pick up. I'm a skydiver and have a pretty good sensce for wind speed and would say they began to gust up to about 8 MPH. Even with these gust the scope viewed fine with only a minimal vibration at lower maginifications. Increasing the magnification amplified the effect. Still visual viewing was still tolerable. Under these conditions, however, I would imagine photography would not be a rewarding experience.

SUMMARY: I am pleased with my purchase of this scope and it has met my needs for visual viewing and more. It's portable enough for the rewards the aperture gives. It's easy enough to set up. The GOTO works as advertised once you pay your dues and learn how to align the scope. The price is very good for what you get. However, for you folks set on astrophotography, I would recommend not setting your expectations too high. You might seriously want to consider a different mount or scope package altogether. Some astrophotography may be doable, however, I'll let someone with more experience than myself judege that.

Well folks, that's about it! (Finally!!!) I do apologize if I rambled on too long, stating the obvious or leaving something out. I really wanted to give a detailed report from a newbiew perspective. So I had to balance brevity with detail - it' pretty obvious which one out. Hope this little diatribe proves useful to somebody.....

Best Regards,

Landmissle C11SGT-XLT