Skymax 127 SupaTrak

[A McEwan]

Hi all!

I've owned my Skymax 127 SupaTrak for several weeks now, so have written up some pretty exhaustive notes about my experiences with it. These following paragraphs show some of these experiences.

First Light:

Location: back garden. Conditions: clear and cold. Unfortunately, there is not a lot of viewing potential from my back garden as there is a street light in every direction, but I can at least spot brighter stars and the planets. To test the mount I used my ED80 and set it up according to the instructions. This meant making sure the tripod was level (using a spirit level) before screwing on the mount head. Then the ‘scope was attached and the power supply plugged in and switched on. The ‘scope tube should then be pointed towards north and levelled horizontally. The package included a compass, but I could make out Polaris so used that as a guide. The fixed part of the fork arm mount has a latitude scale and the portion that moves in altitude has a pointer. When the telescope moves up and down, the pointer moves and points to the latitude or degree angle that the scope is pointing at. When it points to zero, the tube is level, when pointing at 90, it’s at zenith.

The two targets I used as test subjects were Mars and Castor. I used a Meade 6.7mm eyepiece in my ED80, giving 89x magnification, and got ‘locked on’ to Mars first. Detail was apparent of course, but I was testing the mount rather than the scope, so I got it centred using the arrow keys, made sure tracking was enabled, and went inside to make a cup of tea. When I returned about fifteen minutes later, the planet was still within the field of view (about 1 degree – it was an ultra-wide eyepiece) but had drifted somewhat. Nevertheless I was very pleased! I then slewed to Castor and repeated the test. Same result! The tracking seemed to be quite good.

Initial Issues

Other issues did reveal themselves though. Focusing resulted in much shaking of the view, which I attributed to the somewhat flimsy tripod legs and plastic accessory tray. Also, the power supply jack plug kept on coming out of the socket, which disrupted the power supply, and meant starting over every now and then. I resolved to have a go at fixing these issues before abandoning hope and resorting to sending it back for replacement.

The tripod legs were swapped out for a set from an EQ-3 style mount, but I had to drill out slightly larger diameter holes for the larger (8mm diameter) attachment bolts. This was easily done, as the tripod hub is metal (aluminium I think) not plastic. This modification made for a much more sturdy setup. Also, splaying the male pin segments in the jack plug input socket (following advice found on this forum) did improve the fit of the plug, but a piece of electlrical tape wrapped around the mount and holding the plug in serves very well to prevent it coming out at all.

Second Light…took place at a local dark sky site on a cold December night. I set up exactly as I had before and started observing. The focusing jiggle with the ED80 was slightly improved but not completely eliminated. Now on this second night the tracking was not as good as it had been on the first night. I reinitialised a few times and then resorted, as everybody must occasionally, to reading the instruction manual. It seems that to maximise tracking accuracy and minimise backlash errors it is important to use certain direction keys when setting up rather than others. For example, when levelling the tube and when pointing at Polaris (setting latitude) it is recommended to finish those procedures using the /\ and > buttons. Also, whichever of those keys I use last when levelling the tube before resetting the power, I should then make sure it is also the last one I use before setting the latitude after acquiring Polaris in the ‘scope’s finder. I think I’d missed that. By the time I’d realised this it was too late to do anything about it, so I resolved to try those tips out next time...

Tube Assembly

As for the 127mm Maksutov tube assembly that came with the mount, I'll be brief and say it's a keeper! The focus knob is small but quite smooth in operation. Focus is achieved by moving the primary mirror, which can result in some ‘image shift’ when focus direction is changed, but it is really not that bad at all. Views are sharp and bright, and I was able to resolve considerable detail on Mars at 230x. By comparison, the same detail was visible in a 6” f8 Newtonian on the same night, but the Newtonian’s view was slightly brighter. The sky background was darker in the Mak though. I noted that when used on the SupaTrak mount the focus jiggle that marred my experiences with the ED80 was much better with the 127 Maksutov. The tube is shorter, so I suspect that the length of the telescope tube may have a bearing on that.

It is a very rewarding telescope. Clusters appear very contrasty and sharp, planetary features are sharply defined, and the Moon is literally out of this world! The stark whiteness of the lunar surface explodes out of the eyepiece and the contrasting black shadows of crater depths and rilles appear to be etched or engraved on the view. It is a memorable experience viewing the Moon at high magnification with this telescope. The field of view is slightly limited, as the long focal length means that you’re never going to get a truly wide-field experience with this ‘scope. My Vixen 22mm LVW with an apparent field of view of 68 degrees yielded 70x magnification and a true field of about one-degree, which is perfectly respectable. The telescope split Rigel easily at that magnification, with clear black space between the two components. M42 showed remarkable detail, with a really 3D effect in the clouds of nebulosity. Given that this telescope is replacing a 6” f8 Newtonian in my collection, I do not think that I’ll miss the extra inch of aperture, and the overall quality of the views in this telescope can be described as very pleasing. It really is a joy to use.

(click to enlarge)

(click to enlarge)

I do have further notes re my use of the setup, so if you're interested for yet more blurb just PM me!

Hope this helps,

AM 8)

[John]

Thanks for the review AM - your experiences mirror mine with the SupaTrak. I bought the scope with a mind to put my Vixen ED102SS F/6.5 refractor on the mount which was OK but I had the vibration problems that you experienced a little worse despite, as you did, upgrading the tripod - the Vixen is a little heavier and longer than an ED80. My conclusion is that these mounts are ideal for short tube scopes such as the Maks or A 5 inch SCT or an F/5 refractor up to 102mm. Longer / heavier tubes do seem to be a bit too much for them.

I wonder how one would fare on the EQ5 steel tube tripod if you could get it to fit ?.

John