Alan64

No one has suggested that, but those who have difficulties in that must be considered as well. Image-erectors for Newtonians are out there, but the industry hasn't been very forthcoming in providing quality units; lack of demand, lack of supply.

Anything extra added to the optical path can only degrade an image, or not adversely affect it at all. Many use barlows, diagonals, and filters with their telescopes, but you want those additions to be as invisible as possible to the telescope's optics. Now, that doesn't mean that you have to sink a lot of money into those items, but you do want a happy medium, a balance. Concrete-cement between two bricks is better than cake-frosting, but a solid piece of stone is better than both; albeit for the lack of a better analogy. The barlow you've chosen is from a reputable brand, and consistent in quality for the most part. SVBONY has been around for a while. I don't have any of their products myself, but I've not read of any outstanding complaints. In the end, I cannot tell you either yea or nay.

Of course you can observe the Sun with a Newtonian, with a safe solar-filter, but it becomes known to a supervising adult that a Newtonian is not suitable for daytime/terrestrial observations, of birds in trees and ships at sea, therefore a Newtonian is not likely to be taken outdoors during the day, unless a safe observation of the Sun is carefully planned beforehand. But I don't think that too many parents wanting to introduce their children to astronomy, and beginners themselves, are even aware of being able to observe the Sun safely. Solar observations with a telescope tend to be of an advanced interest. You can trust a child with a telescope on their own at night, absolutely, but they should be cautioned and supervised when using a telescope during the day. Newtonians, however, present upside-down views of the earthly, therefore they are useless during the day for that, hence the increased safety for children. Just imagine... "I'm tired of looking at birds and ships with our new telescope. It's for looking at stuff in the sky anyway. I know! Let's look at the Sun!" That new telescope happened to be a refractor, and ideal for daytime/terrestrial observations. Then there are those who refuse to observe the Sun at all, safely at that. I asked my late-father to have a look one day, and through my apochromat. He refused, adamantly. But then, he had had cataracts in the past.

Hi Alex, Ah, you got the "Heritage" collapsible; very nice... https://skywatcheraustralia.com.au/product/6-tabletop-dobsonian/ I have an Orion(of California) 150mm f/5 tabletop, a solid-tube... Both the Orion and Sky-Watcher are produced by the same manufacturer, Synta. My own arrived well-collimated, but that's because they had tightened, torqued, the secondary-hub's screws down at the factory, and for the trip overseas. Else, it would not have held its factory-collimation. I'm afraid it's as roulette in that; luck of the draw, a kiss and a promise, et al. Laser-collimators are for much larger and longer Newtonians. Ours are short enough whereby we may look into the focusser and reach back and twiddle the primary adjustment-screws, simultaneously. In addition, cheap laser-collimators require checking upon arrival, and are usually out of collimation themselves. They must be checked and collimated once they arrive, and before using it to collimate a telescope. The finest laser unit, perhaps arguably, is a Howie Glatter. They reputedly arrive collimated 99.999% of the time, but for a price. Rather, I use both a Cheshire and collimation-cap, with one being the fail-safe for the other. As a result, I get rivetingly-sharp views, and at the higher powers even. A Saxon Cheshire, for example... https://www.opticscentral.com.au/saxon-1-25-cheshire-collimator-eyepiece.html#.X1chhyhKiUk A Sky-Watcher Cheshire... https://www.ozscopes.com.au/skywatcher-newtonian-collimation-eyepiece.html If you'd like to include a Cheshire with the collimation-cap when collimating, go with the Sky-Watcher, but not because you have a Sky-Watcher telescope. I don't know who makes the Saxon; perhaps Synta, who makes the Sky-Watcher. Collimation instructions; these are specific to the smaller collapsibles... https://garyseronik.com/a-beginners-guide-to-collimation/#more-169 There are many other instructions and tutorials online on how to collimate a Newtonian, and if you get stuck we're here to help. If I'm not mistaken, Jupiter, Saturn and Mars transit high enough in the sky there in Australia. If you'd like to see more detail, you may need to dim them down a bit, and with a variable-polariser; for example... https://www.bintel.com.au/product/orion-variable-polarising-filter-1-25-inch/?v=322b26af01d5 Simply screw it onto the bottom of an eyepiece, then twist to adjust, and usually in allowing from 1% to 40% of the light to pass through... Jupiter... Mars, if excessively bright... When using the filter for Venus, you will be able to detect the planet's Moon-like phases more clearly. Venus is the brightest of the three planets, by far. A variable-polariser is only useful for dimming the brighter and brightest objects in the sky; the Moon included, particularly when near full-phase. Only you can decide if it's worth purchasing. Plossls are the minimum in performance eyepieces, and represent a great value. You may also need a 2x and even a 3x barlow for reaching the higher powers, and where "Wow!" and "Look at that!" are heard.

The manufacturers provide a less-than-stellar finder with their telescopes; same goes for the rest of the accessories. But you do get a good telescope, and where it really counts. There are plenty of aftermarket finders: 8x50, 9x50, Telrad, and better-quality red-dots.

Bresser is a German company, but most if not all of their offerings are made overseas. I've got a Meade 90mm f/10... They've gotten pretty good overseas at grinding and figuring the optics for that and other mass-produced telescopes. I was floored by that one whilst observing the tight star-cluster and its environs, the "Trapezium", of Orion, one night at medium-power, albeit after I had blackened and flocked the refractor from fore to aft; a deep, inky-black background, and that illuminated wonderfully contrasted against same. The stars appeared as castaways on a ghostly island, the island dropping off into the jet-black sea.

How have you found its performance for splitting double-stars, and planets?

80mm f/15 and f/16 achromats are rather scarce; scarcer than that even. 60mm f/15 achromats are a bit more plentiful, but at a dim 60mm.

A 100mm Maksutov is the closest of the mirrored-designs to a long-focus refractor... https://www.rothervalleyoptics.co.uk/bresser-messier-mc-1001400-optical-tube-assembly.html That one is at f/14, and with a somewhat smaller secondary-obstruction when compared to Celestron's and Sky-Watcher's offerings at f/12.9 and f/12.7, respectively; the smaller the obstruction the better, albeit negligible.

That's beautiful, and the HEQ-5 is more than capable in supporting it.

I have read many times of a Newtonian(mirrors) as being "unforgiving" of simpler, and less-expensive, designs of eyepieces(lenses). It's actually the exact opposite, with the inherent defect, coma, of shorter Newtonians, at f2.x, f/3, f/4, f/5, and even f/6, exhibiting the defect increasingly more as the telescope "grows" shorter. Analogously, a shorter achromat, barely a refractor, is more "unforgiving" of a #8 light-yellow colour-filter when attempting to suppress its inherent defect, chromatic-aberration(or false-colour), and when compared to a Baader "Fringe Killer" filter. The short-achromat then says to the Baader filter, "You've made me beautiful, my darling. I'm forever in your debt." ...and how. One might slather on a tonne of "cosmetics", but if unattractive before, unattractive in one way or the other forevermore.

Our mounts are lost in time with those 8mm shafts.

I don't know. You can try it with a Sky-Watcher cable and see how it works out.

I was able to get the pier that GSO made for our mounts, but that was back in 2003 or '04, I can't recall exactly. The mount has a little difficulty with my apochromat, but mine's a porker for a 102mm... The pier is, in fact, for longer refractors, only, and to keep the rear of the telescope from colliding with the hub and legs of the tripod. As far as I know, only Andrews Communications of Australia still carries the pier, and listed here near the bottom of the page... http://www.andrewscom.com.au/site-content-section-10-guansheng.htm If you're interested.

It appears that GSO has complied after all... https://agenaastro.com/gso-flexible-slow-motion-cable-round-handle.html

What telescope(s) are you using on the GSO mount? Also, did you not get any knobs, without cables, with your GSO? My own was made in the same factory as yours, but branded differently.

I'm afraid that TS made an error in that, unless the manufacturer of the mount has complied with the 6mm standard in recent years. The axes' shafts of the OP's GSO and of my own are 8mm in diameter.

I get the gist that you have a refractor mounted. You will need cables in that event.

This one... https://www.teleskop-express.de/shop/product_info.php/info/p1753_TS-Optics-Altazimuth-Mount-GSAZ-with-fine-adjustment-and-tripod.html

Actually, all manifestations of Newtonians require at least some collimating... https://www.skyatnightmagazine.com/reviews/telescopes/sky-watcher-explorer-130ps-telescope-and-az-eq-avant-mount/ The secondary-mirror is collimatable, and with a bundled hex-key. Usually, with conventional Newtonians, it is the secondary-mirror that is more difficult to adjust than the primary-mirror. On the other hand, and regrettably, a Newtonian is best for children, for the Newtonian design is not for use during the day, when the Sun is up, but for use at night after the Sun has set. All other designs of telescopes can be used during the day, for birding and sight-seeing, but if pointed at the Sun the telescope must be equipped with a safe solar-filter. Children should always be cautioned against pointing a telescope at the Sun, and watched even whilst outdoors during the day with one. Achromats(crown-and-flint refractors) are only "cheap" due to smaller apertures(60mm to 80mm), and due perhaps even to the age of the design. At the age of 8 or so, I began the pastime with a 60mm f/11 refractor. If your grandson lives with his parent(s), certainly they can help with sorting out a Newtonian when needed, no?

The slo-mo drape... Those that drape, and out of the way, were made in Japan. I'd give or trade <insert here> for a pair of those. This alt-azimuth of my own came with at least one 8mm cable. It also came with two 8mm knobs, without cables, and the way I prefer. All three are shown here... 8mm cables are difficult if not impossible to source. However, 8mm knobs only may be found more readily, perhaps even from non-astronomy suppliers; for example, the 5/16"(7.94mm) of style-1 within this U.S. listing... https://www.mcmaster.com/unthreaded-hole-knobs/unthreaded-hole-knobs-6/ ...albeit only up to 38.1mm in diameter. The cables made nowadays are stiff as an oak board, comparatively.

If you're wanting to take photos with a DSLR-camera, you will need a large, electronic go-to EQ mount, and a small telescope; lots and lots of euros. If you want to use a "smartphone", or a small point-and-shoot camera, you can take photos through the eyepiece, with a larger telescope, then to share them with family and friends on social-media sites, like Facebook, or Twitter, et al. Such would be limited to the brighter and brightest objects in the sky, that you can barely or easily see with the eye only, yet impressive in their own rights. But if you're wanting to take bright, colourful and sharp photos of objects in the sky that you cannot see at all with the eye only, again, lots and lots of euros. Omegon has been around for a while. At most, I'd say that they're at a slightly less level of quality compared to the well-known brands. However, I wouldn't put it past Omegon's parent-company to place a spherical primary-mirror within an f/5 tube, and as Synta has done for "Celestron" in the past. This is a "Dobsonian"... https://www.astroshop.eu/telescopes/omegon-dobson-telescope-advanced-n-203-1200/p,48730 You motion it left to right, up and down, and across the sky. Although, it's not good for astro-photography. Here's the kit you've considered... https://www.astroshop.eu/telescopes/omegon-telescope-n-150-750-eq-4/p,22465 You don't need a large telescope for astro-photography... https://www.astroshop.eu/telescopes/skywatcher-telescope-n-130-650-explorer-130pds-ota/p,25455 ...the smaller the better. But you would need an EQ-3 or EQ-5, a go-to variant preferably, for success; yet again, lots and lots of money. In that this will be your first telescope, yet with an earnest desire to take photographs, I would suggest this kit... https://www.astroshop.eu/telescopes/skywatcher-telescope-n-130-650-explorer-eq-2/p,5017 ...or this new-fashioned one... https://www.astroshop.eu/telescopes/skywatcher-telescope-n-130-650-explorer-130ps-az-eq-avant/p,56248 Over time, you can get some better-quality eyepieces, and take good pictures through them.

Mars has an eccentric orbit round the Sun. At times, Mars is close to the Earth, at other times far, far away. The other night, I was strolling about outside, and suddenly saw a red "star" rising up out of the east. I brought out my 100mm f/4 Newtonian and had a look-see. With a 4mm SR eyepiece inserted into a 2x barlow, and for a simulated 2mm, I watched that ball of orange-sherbet over and over. It took a bit over 30 seconds to traverse the field-of-view, and at 200x. I then took a shot of it... That was about the size of it, and seemingly not particularly close to the Earth. A 250mm aperture is certainly capable of realising up to 500x; realistically up to 300x or so, but only if the collimation is spot-on, and for sharp, pleasing views. Collimation is made much easier if the primary-cell is spring-loaded, with springs of metal instead of rubber, if not already so equipped.

I once had a Vixen GPD... I never got a chance to "trick" it out with a motor(s). The Vixen SP is seemingly in between a current EQ-3 and EQ-5, perhaps leaning more towards an EQ-5 in robustness. It should be possible to motorise only the RA-axis of the SP, and attach this... https://www.firstlightoptics.com/reflectors/skywatcher-explorer-130p-ds-ota.html ...for visual and casual imaging. Then, I also had, for a brief span of time, that same Vixen 4" achromat, and on a GP mount...

Here are size-charts for "Dobsonians" and other designs... A metric-chart of telescopes in general, the model six feet in height as well... It's interesting to note that the tripod-type telescopes sit higher up a bit, albeit most with smaller apertures. Incidentally, you are more comfortable, and see more details, whilst seated in a chair; not standing. It's difficult to place a larger telescope on a tripod, compared to a "Dobsonian". Compromises must be made. I've found this 6" f/5 Newtonian on a tripod-type alt-azimuth to be an ideal compromise... ...and made possible by the shorter 6" and the aluminum mount. I've since removed the pier of that mount, and for this 5"... The pier is only necessary for longer refractors. Without the pier, I can carry that mount with one hand, but not with a telescope attached of course.