sxinias

My first DSO was the Sagittarius Star Cloud M24 taken piggyback (Canon 1000D, an old 55mm f/2.2 SLR lens, SkyWatcher AZ GOTO mount, 1600ISO, 20 seconds).

Six months later I captured M1 (total exposure of 17 minutes, C6S with CG5 mount and 6.3 focal reducer, Canon 1000D at 1600 ISO. This was also my first shot using a polar aligned equatorial mount )

One year later M8 (Canon 1000D, 1600 ISO. Total exposure time 30 minutes and 56 seconds, C6S OTA with a f6.3 focal reducer using a SkyWatcher SynScan AZ GOTO mount and tripod).

My favorite M45, Pleiades Rising, piggy back taken 3 months after I started (30 second esposure, 800 ISO; 55 mm f/2.2 lens, Canon EOS 1000D camera, SkyWatcher SynScan AZ GOTO Mount)

Mike,

Make sure that your telescope is balanced. An off-balanced scope can do what you described. I have an over sized and overweight scope on my SkyWatcher mount a C6S and balance is important.

How to balance? Take the scope off the mount. Install a 25 mm eyepiece. put a pencil on a table and place the telescope on top of the pencil at a 90 degree angle with the vixen dovetail resting on top of the pencil. Move the scope until it balances on top of the pencil (actually you can't perfectly balance it but you will see where the balance point is located). Put a mark where the balance spot is on your dovetail. (I used silver fingernail polish to make it easier to see in the dark). When you install the telescope make sure that the mark on the dovetail is centered in the mount's dove tail saddle.

If that does not solve the problem, then before your warranty expires, contact your dealer for warranty service. I had to do that with my mount soon after I received it last year. It has been well over a year since SkyWatcher repaired my mount and it works great. I have used it very much and even have put an 8 inch SCT on it for a while. The cause of my mount's failure was the hand controller mother board. SkyWatcher said that they replaced the mother board but I suspect they just sent a new mount as some scratch marks mysteriously disappeared.

Goto accuracy of the mount is excellent as long as you keep all the nuts and bolts on the tripod tightened. There are some other things to do to reduce the vibration caused by the tripod such as epoxy between the legs and mount's leg sockets, lowering the accessory tray, etc.

Joe

As you may recall, I had the motor speed problem under discussion that morphed into a more serious problem (azimuth drive, hand controller connectivity, etc.) I sent my mount back and heard from my vendor today. SykWatcher's UK distributor has repaired my mount and it is on its way back to me. The repair was to replace the mother board in the hand controller and provide a new hand controller cable. Will let you know how well it works when I get it back.

If this is truely the fix, then the problem is beyond self-repair.

Sxinias

Macavity,

Great photographs. Thanks for taking the time and effort to make and post them.

Maybe my initial hunch that an electrical connection is at fault is worth looking into. Your mount worked fine for a while, then variable altitude motor speed problem. When you opened up the mount and did your first intervention, you could have possibly jiggled a wire or connector and improved the electrical contact. Closed up the mount and it worked for a short time before the loose connection opened up again from vibration, etc.

If you open up the mount again, you may want to take a look at all the electrical connections to make sure that they are firmly in place and making good contact. One culprit is solid wire instead of stranded wire …. Small diameter solid wire can break inside the insulation or at connectors and make an intermittent contact that can be a devil to find. Like I said, I’m just guessing here …….. but ……… back in the early days of personal computers many a repair man made a good living just pulling out boards, polishing the contacts with a pencil eraser and putting the boards back in again.

BTW on the astronomy forum the SynScan goto mount discussion has drilled down to the SynScan hand controllers. Three people who have three different kinds of Skywatcher mounts (azimuth, GEM, and the autoDOB) that use the SynScan Hand controller are experiencing the same failure mode. (In the middle of performing a two-star alignment the controller will simply freeze up. Turn off the power, turn it back on, and the handset says it can't connect with the scope. Turn off the power and push the scope or connectors a little, then turn the power back on, it usually reestablishes a connection. Problem gets so acute that you generally can not complete an alignment, or if you do, the problem occurs soon afterward during a slew.) The only components in common with the three mounts are the hand controller and controller cable.

There is no evidence that the two types of failures are connected but if you make a stretch and assume a common source for the motor speed variation problem and the hand controller lost contact problem you are left with four common items …. the hand controller, the controller cable, the female plug in the hand controller, or the female plug in the mount. Like I said …. an assumption that is a stretch.

Looks like you have the ball on the motor speed variation solution quest now that you’ve opened up your mount. Let us know what you find next. I’m still waiting for the SkyWatcher distribution to come back from vacation

I agree, its begining to look like getting a good mount is like wining the lotto.

Sxinias

Mcavity,

Thanks for the excellent report and so much for my loose connection theory. If not tooooo much trouble, photos would be nice as well as your update.

Question. Were there any issues involved in putting the mount back to gether?

Sxinias

Let us hope these are just random failures and not a big gotcha. It would seem that given the number of NexStar mounts sold, that if problem is systematic that the forums would be full of postings. However, as far as SkyWatcher goes, it is too new on the street to have time to establish a track record.

I don't know for sure, but I believe the motors as well as most of the rest of the SkyWatcher AZ mount components are identical with some of the Celestron NexStar mounts. In the PC computer world back in the 1980s, we would call the SkyWatcher a Celestron clone. True there are some differences but mostly appear to be firmware related.

BTW: The Firmware in the version of the SkyWatcher SynScan AZ mount sold in the USA is completely different from that sold in Europe .... in the USA SkyWatcher makes little attempt hide the mount's NexStar origin. see:Sticky: SkyWatcher SynScan Alt/Az GOTO Mount Variants - Astronomy Forum

Sxinias

I have the synscan Alt/Az goto mount with a Celestron C6S mounted. I also experienced the internment slow down during azimuth slews. The problem was more pronounced during manual slews than during slews commanded by the hand controller. The problem became very acute but like reported, did not appear to impact goto accuracy.

The problem went away as suddenly as it started only to be followed by a far more serious problem .... erratic and uncontrollable azimuth slews. I suspected a loose connection and suggested to my dealer that I open up the mount to see if that were the case. The dealer replied not to do so but to sent it back to them for warrantee service or replacement. The dealer could not repair the mount …. so much for the loose wire theory …. and returned the mount to the UK distributor for repair or replacement. I did not open the mount so I can not comment on its innards.

The mount is new on the street. Let us hope that it does not have any major systematic defects …. the power plug and shaky tripod are enough as it is.

BTW I did solve the power plug issue with my mount by increasing the tripod leg angle from 65 degrees to 70 degrees (used by Meade on their DS2000 tripod). This plus tightening the power plug nut with a pair of needle nose plyiers did the trick. The steeper angle of the legs reduces the power cable’s drag sufficiently to prevent the cord pull-out. I increased the angle by moving the center tray downwards about 10 cm. This also greatly increased the rigidity of the tripod. My tripod is now very stable for its light weight construction and the load I have on it. I improved its stability by tightening all the nuts and bolts, drilling some small holes in the accessory tray and using nuts and bolts to keep it in place, and finially injecting epoxy in the very small cracks between the tripod leg sockets and the legs. This made the tripod steady enough to allow me to extend the tripod legs about 80 percent with out impacting upon goto accuracy. It also reduced the frequency of tripod induced vibration to where it is no longer a major bother when I focus, etc.

Joe

Sxinias

Meade 2045LX3 SCT/DS2000 goto mount

Celestron C6S SCT/SynScan AZ goto mount