Cosmic Geoff

If you choose another mount and use the dovetail bar fixed to the tube, beware of where the eyepiece etc end up. Choosing an alt-azimuth mount with the arm on the same side as with the Dob base is least likely to result in a 'Gotcha'.

A Maksutov telescope would do all this very well. Maks are generally of excellent optical quality, compact and in most cases never require collimation. I have one and still use it regularly despite having a larger telescope. I bought a Startravel 102mm achro to complement it for widefield, but found that I was using the Mak far more. Buying one telescope (or mount) in hopes that it will do everything is a futile endeavour.

Anything is possible. The question is, what solutions are within your budget, or your technical ability? If you de-mount the optical tube, you could fit it with tube rings and a dovetail bar, and buy a mount with the standard Vixen dovetail clamp (alt-azimuth, equatorial, GoTo - your choice). Or you could buy a steel tripod with a flat top, and figure out how to attach the Dob base to the flat top of the tripod. Or you could make something out of wood and stand the Dob on top of it. Or you could fix a sturdy wooden post in your garden, fix a board on top, and stand the Dob on that.

This is a variant of a question other newbies have posed. Be assured, if it is a GoTo mount, it WILL track. ALL GoTo mounts track.

That is a frequently asked question here, and the answer depends to some extent on what telescope you ultimately buy. The point is, that it is desirable to have a set of three or more eyepieces, and the eyepieces normally bundled with a new scope are designed to get you started without deterring you from buying by adding significantly to the selling price. 🙁 The 9mm and 10mm bundled eyepieces are notoriously poor.

The Nexstar 130 SLT is probably an adequate starter scope. You should budget in addition for a set of decent eyepieces and a proper +12 volt power supply. The SLT mount is mechanically similar to a mount from Skywatcher, and both manufacturers seem to offer 130mm Newtonians and 127mm Maksutov scopes. Note that the Nexstar software is easier to use and more user-friendly than the Sky-watcher Synscan software, despite the ubiquity of the Skywatcher mounts. I have used both, so I should know...

The weight for a given telescope or mount can generally be found on the WWW somewhere if you search around a bit. Why do you need the weight? Have you portability in mind? Note that if you are buying a bundle, the manufacturers often include the lightest and most wobbly mount they can get away with. If it's for back garden use, you would be happier with a sturdy mount like an AZ4-2 with steel legs.

What exactly do you want the widefield refractor for? The CA may not matter on some targets. I have a Startravel 102 and use it mainly for dabbling in EEVA imaging and imaging of DSOs. The focuser is not that bad for visual use, and I added a low-cost helical focuser accessory for imaging. I have used it on a SLT mount (probably the same mechaincs as your 127mm Mak mount) Of course, if you spend more money, you can buy a better instrument. 🙂

I would suspect the 9mm eyepiece, if it came bundled with the telescope. The 9 or 10mm eyepieces I got bundled with new telescopes were not much good and spending £50 or so on a replacement worked wonders.

There seems to be no difference between the C6 OTAs supplied with various mounts (except maybe the colour). I have the SLT mount, so can confirm most of the rude things written about it. 🙂 I have seen some of the C6 SLT deals - they are best read as "Good price for great OTA + a free mount you can use till you get a proper mount, and then use the SLT mount for something else."

I do not recommend the use of AA batteries. The main purpose of the battery holder is to avoid having to bundle a PSU with the mount, which would increase the selling price. Instead use a +12v 'power tank' or a mains powered PSU. I have used my Nexstar SLT mount for imaging, mainly with a 102mm f5 achro refractor, but the mount is barely accurate enough for this. It does tend to drift about, and this is also noticeable when using it for planetary imaging with a 127mm Maksutov, where a very small active FOV is used. With a 102mm f5 achro + ASI224MC camera, exposures of a few seconds for deep space imaging are possible. For better imaging performance, you could upgrade to a Synscan EQ-5 mount. I don't like the Synscan operating system, but with the addition of software and a link cable to give platesolving and resync, the performance is impressive.

I managed to fit a Canon 300D camera to a Startravel ST102. It needed a T2 extension tube about 2 inches long to make it work. I regulary use the scope with a ASI224MC camera and a SVbony helical focuser (no diagonal or extensions).

I saw Venus last evening (17th Nov) for the first time in months. Spotted it at around 203 deg azimuth, 8 deg altitude, in between rooftops to SSW at around 16.50pm. I first saw it from the bathroom window & managed to find a spot in the garden where I could view it with my 127mm Mak. Saw crescent.

Do you intend to do any deep-space imaging? If you do, you need to choose the mount with that purpose in mind. If you do not, be aware that the technique (lucky imaging with video) used for planetary imaging is highly tolerant of mount vibration, drift, etc, so the same kind of mount used for visual observation can be used. It does not even have to be an equatorial, as the individual exposures are very short. This could result in a significant economy... I managed to obtain some satisfactory planetary images using a Celestron SLT light duty alt-azimuth GoTo mount and a Celestron 127mm Mak, similar to yours. It is also perfectly possible to perform planetary imaging with a driven equatorial, non-GoTo mount.

Let's be clear about what the Starsense (camera +handset) does. It automatically performs a star alignment, saving one the bother of choosing alignment stars, finding one of them in the finder, then the main scope, and performing a 2-star align or autoalign. While the Starsense is doing its thing, you could be moving accessory gear outside. Starsense works by plate-solving, but it is not a direct equivalent of the plate-solve you can perform yourself with your own camera and software. The results of a Starsense plate-solve cannot be directly accessed. I have found that the Starsense is of most benefit when attached to a quick-deploy setup like my C8 SE, where the whole assemblage can be caried outside as a single unit, Starsense started and the setup ready for observing within minutes (ignoring cool-down time). Personally I have not found the Starsense to be as accurate as a good 2-star auto-align. but it is accurate enough to get objects into a low-power eyepiece and it certainly saves some annoying fiddling about and crouching. And the handset has some handy object lists. If you have a heavy kit that needs to be assembled before use, and which has GPS, the time taken by doing a 2-star align is a small proportion of the total assembly & setup time (typically 20-30 minutes), and it hardly seems worthwhile attaching a £300+ accessory to shave a little off this time. What kind of imaging are you intending to carry out? Your choice of scope and mount implies that you have in mind either planetary imaging, or deep-space imaging of small objects. Be advised that while the former should be fine, the latter is by all accounts NOT for beginners. I have tried unguided images of planetary nebulae with a C8 and the images are no sharper (allowing for the difference in image scale) than those taken through a much cheaper 102mm achro refractor. You may get more satisfying results if you start your deep-space imaging with a small hgh-quality refractor, or even a camera + telephoto lens. Have you acquired and read the book "Making Every Photon Count" by Steve Richards? It is repeatedly recommended here as a guide for would-be astro imagers.

Some images of Jupiter including a transit by Europa's shadow. 127mm Maksutov, ASI224MC camera, captured with Sharpcap4, processed with Registax6. Because of a mistake with a newer laptop and software, I recorded the videos as thousands of .fits files and had to figure out a way of converting them to something usable (=use PIPP to output an .avi file). The images have turned out much better than I expected - I noted the seeing as "not good". I have had worse results with my 8" SCT which seems to under-perform unless the seeing is really good.

Absolutely not. The bigger instruments tend to have a smaller field of view making it harder to find anything. Whether you have GoTo or not is a personal choice. Some people like to 'keep it simple' and enjoy the prolonged hunt of finding faint objects manually. Others appreciate the time-saving of having the GoTo tech find objects for you quickly. And if you want to image, having an adequate GoTo mount is even more desirable.

Neil's image with the 70mm is excellent for a telescope of that aperture. Before you all rush out to buy a cheap small refractor 🙂, I should point out that some years ago I bought a 70mm supermarket refractor (the one in my signature image), and I eventually realised, after buying other instruments, that the objective was rubbish (though other people claimed good experiences with the same Lidl bargain model). I still have a 70mm vintage brass refractor which performs superbly when rigged and mounted for astro use but I have not had it outside for two years, as it does nothing I can't do with my 127mm Mak, which is much easier to manage and also slightly lighter in weight.

It's closer to 5.4 KG. I am not young, but I can still lift the whole C8 SE assembly - OTA, mount and tripod. Saves a lot of setup time. BTW it seems the OTA and SE mount are intended to be kept as a unit - handling that fat OTA on its own without a grab handle needs two hands.

If you want cheap, portable, suitable for visual and suitable for astrophotography, please be aware that you can only achieve one or at most two of these aims at once. 'Cheap and portable' works. 'Astrophotography' and any other of those aims, particularly 'cheap' may not work. EQ mounts are not required except for long exposure deep space astrophotography. For anything else, the extra complication is a liability.

Or reduce the size/thickness of the nylon pads? I see no reason for having a tight fit.

Amber alert! The 45 degree prism is probably not fit for astro use unless explicitly designed and sold for that purpose. I have a 127mm Celestron Mak and the star test with it is superb provided a decent eyepiece is used and not the 'starter eyepieces that come with it (the 9 or 10mm are especially poor). I used my Mak for imaging Jupiter once or twice and got an image showing the size and shape of the Great Red Spot, which proves there was nothing at all wrong with that particular instrument for planetary observation. The Maksutovs in gereral have a fine reputation so your problem may not be with the instrument itself but with the eyepiece or diagonal(s) or the length of time allowed for cooling.

ZWO ASI224MC. I assume you have planetary imaging in mind.

A couple of nights ago I had an odd issue with my C8 SE. In the middle of a GoTo, the tube descended rapidly downwards, losing the alignment, but after re-starting the mount I was able to carry on with the session. It's not clear whether an electrical glitch caused the problem but the vertical clutch did feel rather loose in the downward direction. I subsequently tightened the clutch as follows: Behind the handset storage recess is a small cover which can be removed by undoing 3 Philips screws to reveal a large nut. Give the nut (size approx 1 3/16" ) a tweak of a few degrees clockwise with a suitable spanner.

Sounds a lot. I made a wooden tripod for my SLT GoTo mount, attaching three 35mm square legs to a spare "bowl" SLT tripod head. I f you are not handy with tools, tripods (in the UK) are relatively inexpensive, and we can buy a flat-topped version of the heavy tripod used with the EQ-5 and AZ-4-2 mounts for a little over £100. I don't think you need a massive tripod to mount a camera tracker.