Cosmic Geoff

That 'synchronous' makes me wonder if the synchronous motor is self-starting. If it isn't, maybe the power pack is OK and the motor has a kick-starter you have overlooked. (I have a synchronous mains clock that needs a smart tug on the setting knob to start it running.) Your PSU has a British label on it which suggests that, as you suggest, it is a replacement. You need a multi-test meter to check this gear out. For a competent person, making up a new PSU should not be hard. It just has to supply the right voltage and an adequate amount of current.

If that's the case, the supply presumably consists of a step-down transformer, and the problem can be solved by finding where there is a bad connection and fixing it, or replacing the faulty transformer with a new one that gives 12v output with a minimum of 8,4 watts.

Writing as a former electronics engineer: it definitely says "12v AC", but why? One could easily get 12v AC from a transformer, which is not a flat object, wheras a 240v to 12v DC power supply would look more like the object in the photo... Do the insides of the PSU, or the motor, offer any further clues?

If you happen to own a Startravel 102mm you can have a go at using it for imaging, and you can get some results. But if you want to do some serious deep-sky imaging you should buy something like an ED scope - the experts can advise which one. You will also need an expensive heavy-duty GoTo mount and (I suggest) the book "Making Every Photon Count" by Steve Richards, available from FLO.

There are various other choices and some people will recommend a Dobsonian mounted scope (because nearly all your money goes into the telescope rather than its mount). If you really want one of the two you cite, either would be fine. I have a Startravel 102mm f5, which is a bigger aperture and shorter focal ratio than the Evostar and while I can see the chromatic aberration it's not generally a critical problem. The Maksutov should be a fine scope (nobody ever complains about having a bad one) and is a size smaller than my Maksutov - an instrument I intend to keep. Either would be a handy grab'n go scope regardless of what you buy or upgrade to later.

I would suggest that you clean the outside of the corrector plate and see how that goes before you think of removing it. The corrector plate already has an obstructing mirror stuck in the middle of it, so a few specks of dust on the inner surface or on the main mirror are not going to make the performance any worse.

The picture shows a significant amount of dirt on the outside of the corrector plate. There is no evidence in the photo of any dirt inside.

How do you know that the mirrors (enclosed inside the scope body) are dirty? How would the dirt get in there? Dismantling these scopes is not a task for novices. If you are not confident about cleaning the outer surface of the corrector, it would be wise to let someone experienced do it.

That is a rather short focal ratio (f4) better suited to low power work eg viewing star clusters etc. It is likely to be quite demanding of eyepieces so I suggest you buy some decent ones (which can also be re-used with a future scope purchase).

What is your budget? The entry level outfits with GoTo will not offer a significantly bigger aperture than you already have. If you want a (visual) outfit with a non-wobble GoTo mount and a useful increase in aperture on your existing scope, brace yourself for some major expense. You could also look at Dobsonian mounts fitted with GoTo or digital setting circles- not any cheaper but might appeal to you.

A dew shield for a Maksutov or SCT should be regarded as a standard item, not an optional extra. Manufacturers clearly do not like to include them because it makes their product look big and naff. But all refractors have dew shields. 🙂 As others have said, it is easy to make a dew shield out of cardboard etc if you don't want to pay for a smarter looking one.

Mechanical and optical parts will last indefinitely if well cared for. Electronic parts may fail or become obsolete sooner than mechanics or optics. That includes older cameras - even if they work fine you may find that the utilities don't work on anything later than Winows XP. But I expect you will be looking mainly at 'nearly new' gear in which case, as suggested above, if it looks good and the seller seems reliable, then the gear is probably OK.

I suggest you read the other threads on this forum where a similar question was posed, and look at the 'Beginner scopes' offered by forum sponsor FLO.

A new SCT should not need collimating, but it is worth checking that the collimation is in fact good. A star should look like a point, or with a high power eyepiece like a tiny dot with circles around it (in good seeing). (This assumes you have a good quality eyepiece, not one of those starter kit things. Which is one reason I suggested buying a good eyepiece). When out of focus, a star should look like a circle with a hole in the middle. It should not look like a badminton shuttle. If you suspect this is the problem, I suggest you contact your dealer for advice, rather than trying to correct the problem yourself.

I thought I would describe my EEVA setup in hopes that it will help or inspire anybody who is interested in EEVA and wondering what to do. 102mm F5 'Startravel' achromatic refractor, ASI224MC USB3 planetary camera, EQ5 Synscan GoTo mount, Sharpcap 4 software, Dell Vostro laptop (7th edition, i5 processor, 8GB RAM, 256GB SSD, 42WH battery) None of this, except the laptop, was bought with EEVA in mind. The refractor - there are better refractors, but this model is cheap, quite well made, and the chromatic aberration etc is not too obvious in this role. The f-ratio matches the camera well, giving a ~0.5 deg. field. The camera - this is a sensitive camera with low noise. A bigger sensor would give a wider FOV but would cost more. The mount - as many of you will have learnt the hard way, Synscan mounts are not easy to use, but the plate-solve & resync available in Sharpcap 4 transforms this mount from an annoying and inaccurate ornament to a really useful tool. I previously used a SLT mount but while easier to use it was less stable. Sharpcap 4 - installed when I upgraded to this laptop. I originally got Sharpcap 3 for planetary imaging but it works just as well for EEVA, and the plate-solving available via this version is great. In a recent outing, this setup was highly productive and I was able to 'see' and record quite a large number of objects in 2 hours. Aimed at Mizar, it separated the 14" double onscreen with ease. In terms of objects made visible, this competes with much larger visual telescopes and has shown me objects I have never seen with anything else, including M1, M33 and Pluto.

Not unless you have incontovertible evidence that it's faulty. Anyway those 10mm starter eyepieces are all poor. Just buy a better one.

There is an Ioptron alt-az GoTo mount which is a little cheaper. Check out the price of a used Celestron C8 SE GoTo outfit. This is an 8" SCT with alt-az GoTo and if you are only interested in visual should tick several of your boxes. They often go for far less than the cost of a new one.

To see galaxies beyond those you mention you need dark skies. What are the skies like at your location? I took my 8" SCT to rural Devon a couple of times and could see far more galaxies than at home. I also put together a video- assisted astronomy outfit with a 102mm Startravel, an ASI224MC planetary camera and a GoTo mount, and this proved startlingly effective at detecting faint objects at my home location, detecting a whole lot of galaxies I could not see visually even with an 8" SCT at my home location. I assume you mean abandon GoTo on grounds of cost. If you are working in light-polluted skies you may be disappointed at the number of galaxies visible with a 10", and also frustrated at the difficulty of finding anything without a GoTo. Your choice, of course. I recently uprated my EEVA mount to a EQ5 Synscan and added software for platesolving and resync, which quickly places objects (visible or not) right in the middle of the FOV.

The answer will depend on the total load. The laptop might be the most tricky item to power in the field, but a modern laptop with SSD will image for several hours without an external power supply. Older models with hard drive consume a lot more power.

The kit 10mm and 9mm eyepieces from Celestron and Sky-watcher do not have a good reputation. I'm surprised you find it that bad, but you would find it worthwhile to invest in another 10mm eyepiece of better quality, plus a 25mm to fill out your range, as an absolute minimum.

Why wait on the weather? You can do the suggested test indoors.

Not necessarily. If you were using a kit eyepiece of 9 or 10mm focal length for the higher-magnification views, this would explain the poor performance, as these eyepieces are not much good and should be replaed by something better. I bought a Celestron Omni barlow lens to replace a kit Sky-watcher Barlow and found there was no difference at all. A daylight view would inevitably be darker at higher magnifications, and the 'seeing' would also affect the view.

I looked again at dusk and around 5pm, and saw the crescent moon, Jupiter and (with binoculars) Saturn and Mercury, but not Venus. I have seen Mercury with the naked eye on other apparitions - one needs to look in the right place at the right time in good conditions. Venus is at inferior conjunction on the 8th Jan, a few degrees N. of the Sun.

This afternoon I managed to observe the Sun (no sunspots), Venus ( a large and very thin crescent) Mercury (a dot), Jupiter, and the new Moon. 127mm Mak SLT, solar system align on Sun (using full aperture solar filter for this). Quite a good bag on one of the first clear days in almost a month.

OK, that's your lead. So have you done the test I suggested above?