C6-SGT: REVIEW:
The insatiable appetite for astronomy never ends. Having started my journey with an 8” Dobsonian, a journey which both my family and I enjoy endlessly and will continue to do so for the rest of our lives, the need to bring in something different and try to further enhance this wonderful hobby never escaped me. This idea bore fruit after three months of waiting and saving, to finally set my eyes on a brand new C6-SGT from Celestron.
PACKAGE CONTENTS: ( Three boxes ).
1. Tripod.
2. Mount head.
3. Spreader tray.
4. Nexstar Remote.
5. E-Lux 25mm Celestron.
6. C6 OTA with Starbright XLT coatings.
7. Diagonal – 1.25”.
8. Two instruction manuals.
9. The Sky Planetarium CD.
10. DC Car Adapter.
11. Finderscope. ( note: Bracket for the finderscope comes attached ).
12. Caps for all, i.e., eyepiece / diagonal / OTA.
13. Weights – 11 lbs.
CG-5: THE MOUNT:
My first introduction to a German Equatorial Mount. There were moments of dread, fearing the worst on the trails of a complicated EQ mount. However, once my family and I set eyes on the Mount itself, all was forgotten. My two children quickly made a check list while my wife and I started to assemble the Tripod. With directions from my children, the assembling of the CG-5 was done clinically and efficiently. It took us under 30 minutes.
Initially, I extended the legs fully and to my surprise, the mount was a good 6’. The legs are a beefy 2” stainless steel and once the legs were collapsed, the CG-5 looked quite solid. I would daresay, this mount would easily hold an 8” Reflector or a 6” Refractor. In our case however, the mount was more than adequate for the C6 OTA. At the back of my mind, I had already begun calculating the accumulated weights of a DSLR at Prime Focus or heavy Eyepieces like the Baader Hyperion 8mm or an Explore Scientific 11mm coupled with a Televue Barlow. Newcomers like me, interested in casual astrophotography, would do well to keep this at the back of their mind, i.e., accumulated weight.
In my estimate, the mount with Tripod and weights should be near to 19 kgs. If one needs to carry this singly, the head could be separated and the Tripod legs closed for easy transport.
First timers who need to deal with an EQ mount should not feel overwhelmed, but at the same time, read the “Manual” provided thoroughly and practice both alignment as well as get acclimatized by knowing exactly where ‘on the field must use’ items like Clutches / Declination axis etc., are positioned so that your session goes smoothly.
One important point to note here is, the CG-5 is designed with a 30-60 degree Latitude. What this basically means is that astronomers using this in the Southern Hemisphere or right on or near to the North Pole would have some limitations for accurate Polar Aligning. There are workarounds though in locations which are somewhere less than 30 degree Latitude. In this regard, I wish to thank both TEL and ARTIC EDDIE of Cloudy Nights for their valuable inputs at the Celestron forums.
The mount comes factory assembled with the “Alignment Peg” between the Tripod legs. NOT on the North Leg as one would think. In my case, this worked perfectly as I didn’t require to relocate the Alignment Peg. All I did was to loosen two bolts and remove the bracket from the front along with the screw. This enabled me to lower the mount scale by another 13 degrees, thus giving me a 17 degree latitude. My Latitude is N 13, therefore I would require to slightly adjust the South Leg by extending it and attaching a weight to avoid tipping over. ( Hope Celestron realize their clientele is not limited to just areas between Latitude 30-60 degrees, but worldwide ).
For our friends in the Southern Hemisphere, the star Octantis can be used for alignment though there are many who are adept in finding solutions with wedges and custom machined parts. I am not one of them though.
NEXSTAR REMOTE:
Initially worked well during mock alignment, when suddenly I had a scare when the message “Transmit Data” appeared. A few posts later and thanks to members at Cloudy Nights again, I was able to overcome this. It was a simple matter of obtaining an RS 232 cable with an Adapter to suit your OS and by finding the requisite ‘Port’, connect to Celestron’s website and download the latest firmware. It worked and so far the Remote is doing fine. I also upgraded the Firmware for Motor Control so that both the Remote as well as the motors are in tune with each other.
Slewing to an object while doing a mock alignment seemed quite smooth with a bit of whining noise which is to be expected and not something which should wake up your neighbours. Later on I reduced the speed to 2 degree which helped lower the noise.
The LCD is clear and the buttons are well spaced out. The red illuminated remote does not spoil your night adaptation. Again I would suggest you thoroughly read the manual to get familiar with the various button controls, even though each one has got markings for their intended purpose.
OTA / ACCESSORIES:
The C6 looks quite modest, actually bigger than the pictures you see on the website and or in this review, but quite manageable. Celestron is clearly marked with a sticker on top stating “Starbright XLT”.
The bracket for the Finderscope comes installed from the factory and all you need to do is insert the Finderscope and use the three screws provided to tighten and align. Though aligning is easy, craning of the neck to view is not. Therefore, if one wishes to upgrade, a nice little RACI would be a welcome addition.
The backside of the OTA has a protruded grey knob which is the “Focusing knob” and works well. The diagonal however is something you would want to keep aside and upgrade almost instantly. My Baader Hyperion eyepiece could not be inserted completely and I had to leave the left side screw loose to accommodate it. Not good.
Any good SCT 2” diagonal with 1.25” adapter or an Astrotech’s award winning 1.25” diagonal would be the immediate thing to do. I am hopefully waiting for this to arrive soon.
The Celestron E-Lux 25mm eyepiece however fits well on this stock adapter and the eyepiece itself looks quite good with adequate eye relief and wide field of view.
The knurled ring at the back of the OTA provides for tightening or holding a focuser or camera at Prime focus.
ALIGNMENT:
Mock alignment is one thing. Going out to the field and see a sparsely star lit sky from a light polluted city dome is another. Monsoon season coupled with a bright Moon do not help matters either. Patience wears out quickly and here’s where one must exercise diligence and determination.
A couple of nights with no rain though still partially cloudy, we took the C6-SGT for our first outing. Our Latitude and Longitude was entered, alongwith time, date, standard time, zone 5 ( in my case ) and a two star align started. Though the scope itself seems to point at the requisite Star, both the Finderscope and the eyepiece failed to spot it. Fine tuning with the arrow keys to center the Star/s in the Finderscope first and then the Eyepiece, yielded results somewhat okay though not perfect.
Tracking did not seem to hold up after a minute with the object slowly drifting out of view. Once again, with the help of feedback from seasoned members and their input on trying a ‘Calibration routine”, decided to wait for a night when the cloud cover would be less or non-existent with no rain.
Yesterday was such a night. Faith seemed to aid me as well as Polaris was visible, just above the horizon. I quickly lined up the Tripod with the Alignment Peg pointed straight at Polaris. Opened up the Polar finder caps and eyeballed Polaris. Used the Azimuth / Altitude screws to bring it in center and then fired up the motor.
I decided a two star align followed by four star Calibration routine. As the hand controller gives you choices in case you have trees / buildings blocking your view, I did not worry about this. Everything went smoothly and by the time I got to the third calibration star, both the Finderscope as well as the Eyepiece had the object in view. By the fourth calibration star, things were beginning to look spot on.
FIRST LIGHT:
Hit ‘M’ on the Nexstar and entered ‘042’. Lo and behold, M 42 was dead-on. The stars in the trapezium looked like jewels and the nebula itself appeared quite clear. I was fearing the views between my 8” compared to this 6” would be somewhat anti-climactic. They were not and while still cannot compare to an 8”, not exactly a let- down either. I was using a 14mm Meade 5000 super Plossl with 60 degree FoV.
Next we entered M 31 and the scope slewed right there for the great galaxy to be visible in the eyepiece. With a full Moon quite close to the vicinity, we could still see M 31, probably due to its magnitude of less than 4.00.
We then slewed back to M 42 and I decided to give Prime Focus a go. Inserted a T2i at Prime Focus and through the viewfinder, focused on Orion’s great Nebula and started testing.
Thirty seconds showed some trailing. Twenty seconds did not show much trailing, I therefore, settled on twenty five seconds. Ten light frames later, we were astonished to see the Great Nebula’s color and profile light up the camera’s preview window. It was exhilarating and perhaps the highlight of this basic astrograph equipment. We then slewed to a few open clusters like M 36 / M 37 and they were all bang in the center. Clouds were rolling in and we had to wrap up the session.
To add, views of Jupiter were crisp with the Barge clearly seen. Moon was glittering to say the least with all the craters showing up with clarity. The XLT coatings do seem to live up to its name.
For all the trials and tribulations, mainly due to my location, overcoming these kind of hurdles, adds to the excitement, especially when you pull out something which you always dreamed off. Nothing spectacular but at the same time, something to show and talk about. As long as newcomers to astrophotography learn to understand the limitations of this basic set-up and are prepared to undertake this journey, the adventure would be both exciting and rewarding.
For more serious astrophotography, there are many add-on’s to this mount like a Radial Glider, Polar Finder scope, Auto-guiders etc.,
Clear Skies!
Disclaimer: I am not affiliated / associated with any brand names or vendors mentioned here in this review.
Haseeb Modi.
P.S: I wish to thank all those who guided me in this process of alignment, figuring out on how to overcome my latitude scale and giving some extremely helpful tips on Polar alignment.
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