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I’ve always liked star gazing and attended the Introduction to Astronomy course at Norman Lockyer Observatory a few years ago (which I’d recommend). Since a holiday has been off the agenda for the last 18 months, we decided to spend the money instead on a telescope and take a proper look at the night sky. Here is what I’ve learned from the first couple of sessions …
I chose the Sky-Watcher Skymax 127 SynScan AZ GOTO because:
I wanted a descent scope with a good aperture, but also something compact (both the OTA and the mount) as it will get lugged about and stored in the back bedroom. I can find a few stars but don’t know the night sky, so I wanted a mount that would point me in the right direction. I could probably align an EQ mount with Polaris, but two star alignment seemed easier and quicker, meaning more observing and less faffing. Before the scope even arrived I had bought a Celestron 6.1Ah Lithium Powertank.
The Skymax 127 comes with a VERY basic battery pack that takes eight AA cells. The mount consumes up to 12W so will flatten AA batteries quickly, and rechargeable AA batteries only have a terminal voltage of 1.2V so cannot provide the 12V needed by the mount to operate properly. The scope really needs to be powered from a Powertank or a mains power supply I think.
I chose the Powertank because it’s portable, avoids the trip hazard of mains cabling, and is regulated to maintain the 12V needed by the mount as it discharges. So far a full charge seems to be good for several hours of observing. Surprisingly, there is no power switch on the mount, but I can use the power switch on the Powertank to switch system power rather than just pulling out the power cord!
The first night of observing was frustrating! The second time, after properly reading the manual and doing some online research, went much better. Here’s what I learned …
Make sure there is enough play in the power cord for the mount to turn through 360° in either direction. Movement of the mount can pull out the power cord if it is tight which then loses all of the setup and alignment data!
UPDATE: To really see an object you need to look at it over several minutes so that you become accustomed to the image and your brain begins to pick out the details. In order to do this comfortably, set the tripod height so that you can observe while sitting in a chair. Set the height so that at high elevations, above 70°, you can lean forward in the chair and still comfortably look into the eyepiece. At low elevations, below 30°, I cant over the diagonal so that the eyepiece is near horizontal then observe from the side of the scope.
Make sure the mount is exactly horizontal so that movement of the OTA in azimuth through a rotation stays exactly flat. I used a spirit level during daylight to level the tripod top with the mount removed then marked the leg positions on the patio.
Power up the mount with it set horizontal (using a spirit level) and pointing true north (using a compass) so that it is approximately aligned from the start. At power up the mount assumes it is orientated at 0° altitude and 360° azimuth. This makes it easier to find alignment objects and it stops the mount from slewing in strange ways (ways that cause the power cord to disconnect!).
When finished, Park the mount to its Home Position so that it returns to horizontal and pointing true north for next time. After parking, you can resume next time using the previous alignment data but if the scope has been moved it’s probably best to start again from scratch.
The mount has no real time clock (!) so the date (in month / day / year format) and the time must be entered every time it’s powers up. The mount does remember its location so this just needs to be confirmed at power up unless it has changed.
I align the mount using the 2-Star Alignment method, choosing two stars that are in the same area of sky where I plan to observe. Only certain stars can be used for alignment, there are around 90 to choose from, and it’s worth deciding which to use before you start observing. I’ve set the Sort order for Alignment Stars to Alphabetic (this is remembered by the mount) rather than by magnitude, as it makes the selected stars easier to find.
There are course and fine stages when aligning to each of the two stars. During the course stage the slew rate is automatically set to fast. For the first star slewing has to be done manually, but for the second star the mount will slew automatically to the approximate position of the star (since the mount now has some alignment data).
During the fine stage the slew rate is automatically set to slow. You must finalise the alignment of the chosen stars in the centre of the field of view using the Up and Right arrow keys as this compensates for backlash in the mount (when automatically slewing to objects, the mount first slews fast to just left and underneath the chosen object and then approaches the object slewing slowly to the right and upwards).
Make sure Tracking is switched on and set to Sidereal for stars and planets and to Lunar for the moon (when using the Object List location function the appropriate tracking mode is set automatically). If an object’s position within the field of view isn’t quite central, it can be tweaked by manually slewing (at a slow slew rate), then the tracking function will keep the object centred.
If you think you might return to an object later, it’s worth using Pointing Accuracy Enhancement (PAE) to store tweaks to object positions. PAEs are applied to any objects located within about 5° of the object that was tweaked.
I find Show Position useful when manually locating objects to check the current altitude and azimuth positions, and Identify useful to check what objects I might be looking at!
One nice surprise is that the SynScan controller that arrived has a USB type B connector in place of the advertised 12V power connector. This enables a wired USB connection to a PC which allows the mount to be controlled by programs such as Stellarium (I’ve tested this and it connects with no effort and works fine).
UPDATE: The SynScan controller does a good job of locating objects, but with two lines of display text it can provide only limited information about the objects you observe. Having used the controller to setup and align the scope, I then use Stellarium to control its position and locate the objects I want to observe. Stellarium shows each object in context, provides easy access to magnitude, size and other data, and shows what you might expect to see (more realistically with background DSO images turned off!). I’ve setup the Stellarium Oculars plug-in to show the view through the main scope with different eyepiece and Barlow combinations, and also to show the view through the finderscope. Using the finderscope ocular, I can check what I’m actually seeing in the finderscope to make sure I’m pointing at the right thing, then using the main scope ocular, I can check what I’m meant to be looking for through the scope.
So far I’ve been a little underwhelmed by what I’ve been able to observe! I have a cheap and cheerful 45x field scope which gives a good view of the moon and can just about pick out the rings of Saturn and the moons of Jupiter. With the Skymax 127 the moon is much clearer and I can see details of craters when they are in shadow. Saturn and Jupiter look a little better but I can’t see much more detail and at higher magnification (10mm EP) they are a little fuzzy. I managed to find Andromeda (or rather the mount did!) but it looked like piece of cotton wool and didn’t fill the field of view as I had been expecting. When I looked at nebulae I could see the concentration of stars forming them but had no sense of any colour or clouds.
Is this par for the course, or am I missing something?
So far I’m using the scope as it arrived, out of the box (apart from the Powertank), but I do have on order a few ‘upgrades’ …
Baader Hyperion Zoom Eyepiece – to replace the basic eyepieces that come with the telescope (25mm and 10mm) and to provide a range of magnifications. Baader Prism Star-Diagonal – to replace the basic diagonal that comes with the telescope and to provide a stronger mechanical support for the (rather expensive) Zoom eyepiece. Baader Helical Focuser – the focus control on the back of the Skymax 127 seems very sensitive and I see from another post that this helical focuser can fix this. Baader Neodymium Moon and Skyglow Filter – OK, I was getting a little carried away by this point! – where I live is quite rural but this filter seems to improve matters over and above just removing light pollution. When these bits have arrived and I’ve had a chance to try them I will post again with an update.
I have a Sky Watcher 150 PDS and a Canon 600D I use to take images.
I'm looking at purchasing a Sky-Watcher f4 Aplanatic Coma Corrector for my setup. It's as much as I can afford, but wondering if its a good choice?
One concern i have is that my scope is an f5 which this is designed for f4 but has very good reviews.
My synscan V3 handset is having issues in the goto settings, for example, it may be over 10 degrees out in azimuth and a few degrees out by altitude. For troubleshooting purposes and to save you from asking unnecessary questions, I have tried different locations and made comparisons, I have also tested multiple different targets. My location, date and time are also correct and to make sure, I have tried different variables to see if there is a difference but there is not, the handset is still out. I should also let you know that the difference between the real value and H.C. Value is not fixed and does vary. Help would be greatly appreciated as this has really puzzled me. I have updated the firmware and went to older versions - same issue. I have searched for this topic on the likes of YouTube and other forums and cannot find some information. Fingers crossed one of you can help me with this.
So I have had these Skywatcher Slow Motion Cables for all of 5 minutes and after the damn thing fell off the a second time in as many minutes I tightened it better and the screw sheared off. Fantastic. Any ideas? Drill it out I guess? Send angry correspondence to Skywatcher.
Its now stuck to my Scopetech Mount Zero.
For the life of me, I cannot figure this out. Got to take out my setup last night for only the second time as it's been cloudy for weeks and I've been trying in vain to align my Skywatcher AZ-GTi mount to no avail. I'm using it in ALT-AZ mode for now, and I've probably researched every article and watched every Youtube vid I could find and still nothing is working...I feel like I'm stupidly dense or something because there is something just not clicking in the cranium.
I thought I was supposed to point the dang thing north to start so that's what I did, err, I think anyway. Am I pointing the wrong end north? See picture. Also, I'm reading that the actual scope has to be mounted a certain way on the mount correct? Which way would that be? I've read all of this left/right stuff and those directionals mean nothing to me as it depends on someone's viewpoint. When I aimed north to start, I attempted to align by directing SynScan to go to the Moon first, and that took it so far off course it wasn't even close, it was basically pointing at the ground. I reset and tried again with another start (Vega I believe)...again, wasn't even in the realm of close. I made sure my location settings were correct in the app so that wasn't the issue.
Here's how I got something to "work". I had it track to the moon and when it was essentially pointing at the ground and who knows how many degrees from my actual target, I picked the whole thing up, turned it around, manually aligned to the moon and then clicked OK on the app. I felt like a ridiculous clown doing that but somehow it actually managed to do the trick but something tells me that isn't right on a long term basis.
I'm thinking about getting SkySafari to control the mount but I should probably master the basics first.