Cosmic Geoff

You need to set some priorities. If you are definitely not going to image, you probably don't want the complication of a German equatorial mount.  If you have GoTo, it will save a lot of time and effort if you want to find faint and non-obvious objects.

The Dobsonian outfits are simple to use, and you get a lot of aperture for your money, but they don't track, and don't find objects for you (unless you go for a GoTo version.)

I found the Celestron Nexstar alt-azimuth GoTo system easy to use, a Skywatcher Synscan GoTo rather less so. 

If you live in a light-polluted area, a GoTo is particularly useful for finding non-obvious objects.

You don't have to buy the telescope and mount as a package, or even from the same manufacturer, but it usually saves you money.

Don't get over-ambitious with your first telescope - just get something that works properly, as you will probably upgrade if the astro bug bites.

Whether one prefers 'push to' or GoTo is a matter for the individual.  One advantage of a GoTo mount is that it will track, while a 'push to' in common with a manual mount will not.  If one looks inside a GoTo mount one may find that the motors are small and the motion encoder looks very simple, and in fact in manufacturing terms and retail pricing the 'push to' appears to have no cost advantage.

6 hours ago, Spacecake2 said:

Maybe an 8" computerised like a Nextar 8 se?

I have one, and can confirm that it is totally unsuitable for deep space astrophotography.

BTW, if you quote prices in Australian dollars,  UK residents (the majority here) may not be familiar with the exchange rate.  That camera seems a little expensive, even allowing for the exchange rate.  Be aware that the prime reason for using a DSLR is that many people already own one, and a dedicated large sensor astro camera is expensive compared with many DSLRs.  I bought a used Canon 300D for £25.

I have had this happen with my CPC800.  Never found out why, but some time later I had to replace a failed battery in the power pack I was using to power the mount.

If you have to use AA cells, buy a premium brand, e.g. Duracell.  Budget cells don't work.

Unless you level the mount very accurately, the accuracy of the Solar System align will be poorer than a two-star align.

If you set the OTA tube correctly in the clamp (fully forward) the eyepiece should not collide with the mount at high altitude.

Be aware that one telescope and one mount will not fill all roles equally well.  There is visual observing, and planetary imaging, and deep sky imaging, and for each of these roles a different kind of telescope and a different kind of mount is optimal.  A SCT is great for visual observing, and would be the preferred choice on your generous budget.  And it would be equally good for planetary imaging.  However they are difficult to use for deep space imaging, and a small apochromatic refractor (as commonly recommended) would be easier to manage.

As for the mount, a heavy mount like the EQ-6 would fill all roles, but for visual observing, you don't need it and you may find that for a short visual session that dragging an EQ-6 out of doors (perhaps in two sections, because of its weight) performing a polar alignment, then a star alignment, rapidly loses its appeal.   With an alt-azimuth mount and the Celestron Nexstar software (IMHO easier to use than Sky-watcher's Synscan) you could be ready to observe in a few minutes.  Starsense or GPS could cut the setup effort even further.

You don't need an equatorial for planetary imaging either, just a solid and well-behaved mount, but this is a less important point unless one has no interest in long exposure imaging.

22 hours ago, Mick_1960 said:

It will be great if I can use my laptop to see what the telescope is seeing rather than looking through an eyepiece

That was my idea on first buying a GoTo scope, but I rapidly abandoned the idea as it is not as easy as it sounds.  It  might be easier if you can use a large area (and expensive) sensor, but with the small sensor in a planetary camera it simply doesn't work as the popular mounts cannot aim the (SCT) telescope accurately enough to get the target onto a sensor a few mm across, without a good deal of manual intervention.

It works better with a short focal length refractor, or if you can use plate-solving to fine tune the aim.  But you could end up with a lot of extra hardware and software, just to avoid looking through an eyepiece.

Rather, you could use an astro camera and laptop at the telescope for EEVA (see section in our forum), for observing things beyond the reach of the telescope and human eye.

At a city centre site, a GoTo mount would offer significant advantages as otherwise you will struggle to locate any non-obvious objects.  You could fit a light shroud on the 130p dobsonian, but also consider narrow field instruments such as a long focal length refractor, or a Maksutov.

If you don't go with the GoTo, upgrading the finder to a 9x50 RACI  (right angled, non image reversing) finder would be helpful.

A Dobsonian is the type least suited to any kind of imaging.

49 minutes ago, Just A DarnNice Guy said:

Raise the price $40.  add a RTC.  Get rid of the AA batteries and just use external ion pack. 
Amazon sells 12,000mAH ion packs in the $40 range. Guessing bulk price be in the $20 range thus the added $40 price increase to the scope.
$40 is a small price to pay for something that would actually work instead of the disappointment of the AA batteries.

For a few dollars they should be able to add GPS - even more useful. I understand that a GPS chip costs only a few dollars these days.

The Evolution version of the C8 has an internal rechargeable battery in the Evolution mount.

You want to eliminate the power voltage as a possible issue, so using a cheap or inadequate supply that might blow up your mount is self-defeating.  Only fit one that is correctly rated and delivers +12v tip positive with a 5.5/2.1mm plug.  

+12v tip positive with a 5.5/2.1mm plug is a common configuration, but don't rely on it unless confirmed with the spec sheet or a test meter.

8X 1.2v = 9.6v.  My Celestron mounts malfunction when fed with volts this low.  Should be 12v to 14v,  from a 12v lead-acid battery or a regulated 12v mains to DC power supply of adequate amperage (e.g. 2 amps or more).

I have a Canon 300D which has the same issue in that you can't load the Canon drivers on a modern OS and several of the popular astro utilities won't talk to it.   I found that one of the stock apps in a Mint Linux 19 installation will communicate with the camera so you can access the contents of the CF card.

36 minutes ago, Starwatcher2001 said:

Is it really too much to ask in this day and age that a real time clock be built into these things?

I can only assume that a RTC is omitted in order to shave the initial cost and make the purchase seem more attractive.  A few higher priced mounts include a RTC, IIRC. Having to enter the date and time at power up is one of my pet peeves.   Perhaps if we all rudely demand a RTC as standard, the manufacturers will do something about it.

You don't say what you want to use the camera for.  I have a planetary camera (ASI224MC) which has a significant response in the infrared.  When I tried it with a fisheye lens in the kitchen I found that it worked OK with the IR-cut filter, but without it the colours looked a bit off.  So if you want true colour, you need the IR-cut filter. If you don't then fine.

8 hours ago, Alan64 said:

If for visual-use only, I would suggest motorising the RA-axis only, and to the point whereby I had removed the DEC cable from the hand-controller from my own Celestron dual-drive kit, and for my own CG-4...

I had RA drive only on my EQ-5 before I upgraded it to a Synscan GoTo.  I found it irritating to have the RA and Dec fine controls in different places, and when mounting a long refractor, the Dec slow motion was out of reach unless I used a long rigid extension made from  6mm aluminum tube. I think two powered controls on the same box would have been better.

The internal batteries are a joke - you have to use a premium brand e.g. Duracell for it to work, and the option is only provided to make your scope purchase look cheaper, and get you going. You need a +12v external sypply, not 18v! and not 24v!!

There are lots of battery options for this, which members here have used with success, and they need not cost much, ranging from a +12v 7Ah sealed lead acid battery, to a multifunction car engine starter, to a branded astro power tank, to a LiFePo power tank.   On the AC power side, you can use an adequately rated +12v regulated   DC output power supply (at least two amps) and again there are types intended for astro use (outdoors, wide temperature range)

It makes little difference whether you leave the internal batteries in place or not.  But if you forget they are there, they could leak and corrode the battery contacts.

You will lose time & date (but not location) every time you switch off. That's normal.

We could help more with some input from you about what style of telescope you'd prefer.  Your budget of $400  is a bit low for a telescope on a GoTo mount, which in any case might not suit your inclinations.  If you have really no idea where to start, you could get a pair of binoculars (which could be re-purposed for daytime use) or a basic but useful telescope in the form of a 130mm aperture table-top Dobsonian  newtonian reflector.  I append a link to a UK-market model.  You should be able to find the equivalent from North American suppliers.

http://www.opticalvision.co.uk/astronomical_telescopes-sky-watcher-dobsonians/skyliner_flextube_dobsonian.html

If the bug bites, you can progress to a more advanced instrument that suits your developing interest.

The secondary mirror housing should not be rotating in the plate, and the three collimation screws should slacken off.  I hope that somebody who has worked on one of these will come along and advise.  Seems that you will need to dismantle the front end, sort it and reassemble it. Not that I'd want to try it myself except as a last resort.

33 minutes ago, steve wiz said:

I just looked, that costs a fortune! MUCH more the a 6SLT!   Way out of my budget!

You get what you pay for.  You have not said what you want it for: if visual, then the SE would be 'best buy'.

If planetary or deep-sky imaging, then you want the AVX mount or (for planetary imaging) the Evolution mount or (for deep space imaging) some different outfit altogether, but not cheap.

If you get the 6 SLT, you may be looking for a mount upgrade before long, unless you don't mind wobbly mounts.

I really don't see the point of using 2" attachments on a small Mak with a 18mm hole in the backplate.  I would expect the vignetting to be severe. I don't use any 2" kit even with my 127mm Mak and 203mm SCT.  2" eyepieces come with a premium price tag.

What 1.25" diagonal do you have already?  According to reports, more expensive diagonals give an improvement in build quality, coating life etc rather than any improvement visible through the eyepiece. 

The Nikon would be suitable for deep space imaging in that you get a lot of sensor for your money compared with dedicated astro cameras.

For planetary imaging you should get a dedicated planetary video camera as it will have a faster frame rate than the Nikon. Serious planetary imagers use a planetary video camera.

With a solid mount like the EQ6 you should be able to manage without a focus motor.

I do not know anything about the Orion zoom eyepiece.  A lot of these eyepieces are clones of each other (and look the same in sales photos).  Of the cheaper models, some work fine and some are awful.  Be aware that a common feature is that at the longer focal length of the zoom, the field of view is restricted compared with a standard eyepiece, while at short focal length the apparent field is much wider.

A RACI or right-angle finder would be less of a pain in the neck than the straight-thru finder.  Same applies to the 90 deg polar scope adapter if you feel inclined to buy one.

IIRC a few weeks ago another member was trying to fit a dovetail bar to an old de-forked C8 SCT.

If you can use the wider Losmandy bar, that might make it easier to find a set of 2+1 holes that line up with the bar.

I have had a look at my more modern C8 SE.  The dovetail bar screw holes may not line up in the way you think - mine has two screws at one end of the bar, (spaced around the cast rim) and one at the other.   Looking from the back, the focus knob is at the bottom and the dovetail bar on the left.

At the other end, it does look as though the front casting could be unscrewed and put back at 120 deg rotation.

Opinions differ on the effect of rotating the secondary mirror or correcting plate, suggesting also that it may or may not matter depending on how old the SCT is.  The collimation though is something you can check with a star test.

The chances of getting individual parts of a focuser are very small. Unless you can find another 'dead' scope to dismantle for spares, your only other option is to bite the bullet and buy a complete focuser assembly. (This might be an opportunity to upgrade to a better focuser).

Why do you want a wedge? And why do you want the option of turning the mount into an equatorial?  If you need an equatorial, it would be better to buy a German equatorial GoTo at the outset.

SCTs have thousands of happy owners - they work just fine.

No doubt somebody will point out a difference in performance between a C5 and a 5" Mak, but I don't think it will be major.   The C5 should cool down quicker than some other scope types, quicker than the 127 Mak for instance.  Maks are not renowned for quick cooling - they have thick corrector plates.

These outfits are new variants.  The OTA will be the same as the 5SE and 6 SE, and the SLT mount is the same as used on the 127 Mak and 130 Newtonian, so far as I am aware.

The SLT mount, as used with the 127mm Mak, which has weight similar to that of the  C6 OTA, is on the wobbly side. 

If you put these comments together, you should be able to find adequate reviews of the components.

The C6 SE has the same mount as the C8 SE, so it will be an adequate (visual) mount for the C6.

The result from the 80mm is remarkably good.

I have had consistently disappointing results when unsing a x2 Barlow with a 203mm aperture C8, compared with the same scope withut Barlow..