Alan64
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Posts posted by Alan64
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The covers for the latitude-axis gently snap into place...
The slight spacing between the magnets and the bolt ensure that the covers are able to fully seat.
The RA-axis is aimed at Polaris, more or less, and ready to go with the 70mm f/12.9 achromat attached...
The legs of the tripod are fully retracted, save the slight extensions required to level the mount, and per its built-in bubble-level. I expect I'll be keeping the legs retracted mostly, if not always. The lightest, four-pound counter-weight is attached, and the telescope balanced, more or less.
The revolutions amaze and astound. I'll be wanting slow-motion knobs instead.
No, you're not seeing things. I have a new observing-chair. It's much nicer than the old one...
Although, I'll not be retiring it, just yet.
I'm going to need a two(to three?)-pound counter-weight. I can get an iOptron 2.2-pound, and a 13/16"(20.7mm) drill-bit to open it up. That would still be somewhat less than the Vixen two-pounder, but only somewhat. The Vixen is nigh insanely priced; two pounds of silver, it seems.
"Those interested in Vixen precision optical products can expect to see them available on Explore Scientific's website as soon as October of this year." - GlobeNewswire
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Additional epoxy was just added round the magnets and risers...
...and for peace of mind.
I can still twirl the unused epoxy of the first application round the toothpick, and as I type, therefore this second application should bond well to the first.
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20 hours ago, Franklin said:
Sears? Looks like a Polaris clone.
The refractor does have the same colour as my Sears(Towa) 60mm f/11...
...and in obviously better condition than my own.
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I see the retaining-ring within your image, with notches, and which holds the lenses in place. You can unscrew the chromed barrel for easier access. However, such must be done carefully. I strongly suggest researching "disassembling eyepiece" online before attempting, and read everything you can find. You don't want to get the multiple lenses within out of order, and/or flipped. Take photographs as you go along. You can use a lens-cleaning fluid, or make your own. That can be researched as well.
I took this 20mm eyepiece apart once...
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For what we cannot obtain here, we go there...
https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html
The U.S. version... https://www.amazon.com/Deep-sky-Imaging-Primer-Second/dp/0999470906
I'd perhaps prefer the UK version myself, but I don't image.
Has your son done any visual observing in the past, with eyepieces and a telescope?
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The magnets, and their risers, have been epoxied in place...
The printed cover is on the left, and with only one riser...
After the epoxy sets a bit, I may add more round the magnets and risers. I do have my mixing-palette with the unused epoxy, a "canary in the coal mine", and to test its setting over time.
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Fortunately, as fortune does favour the foolish, the inner sides of the covers each had a small moulding mark in the centre, however vague. I then took my mini drill-press with a carbide drill-bit and drilled them out slightly for a compass leg-tip to nestle within...
Incidentally, the magnet for the blank cover can be off-centre, if one is cross-eyed, but the magnet for the printed cover must be dead-centre, thus requiring a right good rap on the head.
The risers for the magnets, and from a 1mm-thick aluminium scrap-sheet...
The risers were then cut out with "tin snips", and dressed...
The two at far right will be epoxied together, and for the blank cover.
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10 minutes ago, banjaxed said:
Looking at the glamour shots of the completed mount I could not help notice they were taken in front of your new shed. As your shed thread has not had any new posts for a while are we to assume it is finished ?
It is, I'd say, 97-98% finished.
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I removed the taped magnets from the inner sides of the covers for the altitude/latitude-axis, and polished both...
Aren't they lovely?
The cover printed with the degree-scale was fairly easy to pop off when I began this project, but not the blank one. As a result, the edge of the blank cover was damaged a little, with a scratch over onto the bevelled surface, indicated by the red arrow, and a rough edge in that same area. I first scraped the excess off of the scratch, "painted" it with acetone to smooth it, then polished the entire cover with Colgate® toothpaste, then Pond's® original cold-cream, and with my finger-tips only. The printed cover was polished with the cold-cream only. Both covers had some light and micro scratches in addition.
The relatively large scratch is still there on the blank cover, but noticed only via this macro-shot and a brilliant LED-light...
It was quite noticeable before, just looking at it from two feet, more or less, distant.
The small, neodymium magnets are 1.5mm in thickness. The depth of the inner side of both caps, 5mm. The head of the bolt, in relation to the blank cover, protrudes about 1mm into same. The tip of the bolt, in relation to the printed cover, protrudes about 2mm into same.
Hence, the magnet for the blank cover will need a 2mm riser, and a 1mm riser for the magnet of the printed cover. Once the risers are integrated, there will be about 0.5mm of spacing between the magnets and the two ends of the bolt; again, not quite touching.
When I had gone out to remove the covers, with their magnets taped in still, the printed cover was harder to remove, as its magnet was closer to its end of the bolt, the tip.
At present, I'm thinking about making an aluminium spacer for the gap between the saddle and DEC-housing, to epoxy it onto the underside of the saddle's rim...
That would help to keep debris from entering the gap over time.
Alas, I wouldn't have to think of these things if Synta had been "on the ball". -
It may be an EQ3-class, and if those wooden legs are original to the mount-head, then I'd say it's of Japanese manufacture. It could also be one of the very first Celestron CG-4 mounts, and made in China, or Taiwan.
In any event, that's not an up-close shot of the head, which makes it difficult to tell...
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Glamour shots of the completed mount...
It's a whopper of a mount...
The cinder-block on the wee porch is for scale.
By the by, I now have a wonderful solution for attaching the plastic covers, besides glue, onto the latitude-axis. My smaller diameter, thinner neodymium-magnets...
Within the preceding images, the plastic covers for the latitude-axis are being held by the magnets, but it's only double-sided tape holding the magnets onto the covers' inner sides. The magnets are not touching the bolt, and will not need to in future. I will be attaching the magnets with other than tape, J-B Weld epoxy most likely, and spaced to where they will almost touch the head and tip of the bolt, but not quite.
The solution for the plastic covers pertains only to myself, as there is no real need to remove them in the first place. But I will tell you this: I noticed that the RA-axis was not quite set to my latitude, so I adjusted it, and O how smoothly it motioned; luxurious; again, like the thick door of bank-vault whilst closing.Incidentally, when I had cut down and painted the pier-extension, several years ago, and painted it "safety blue", little did I know just how prophetic that choice of colour would be...
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On 23/10/2021 at 17:31, Franklin said:
Just been re-reading all of this thread Alan and your mammoth efforts to re-build/re-create your LX70 mount. I think it is amazing what you have done and the whole documentation with all the pictures you have posted will be a welcome resource for others wanting to re-vamp their EQ5 style mounts in the future. Should be a sticky. 👍
Thank you Franklin.
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Welcome McQ. I have a 6" telescope, and a microscope...
Incidentally, if I combine the two, I get a Maksutov-Cassegrain telescope, which is like a microscope, but for the night sky...
If you ever need any help with whatever pertains to telescopes, we'll be here, and gladly.
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Plossls are economical, yet performance driven. I would suggest 32mm and 12mm Plossls, and a 2x-barlow, to start. A 3x-barlow can be had as well.
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Have you ever used a telescope before?
I always like to up the ante...
If you're stuck at $400...
https://www.bhphotovideo.com/c/product/1141699-REG/sky_watcher_s11600_6_traditional_dobsonian.html
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On 28/10/2021 at 05:46, HiveIndustries said:
So the shop had an Orion XT6, used in new condition, saved everyone a few bucks and I don't have to worry about the 8" being too big.
We've had cloud covered days for like over a month with very very little clearing and she targeted the one clear night this week and was like, "Can I come over and use the big scope?" So I know this is going to be a well received gift, can't wait!
All's well that ends well.
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11 hours ago, Hugo hazendonk said:
Thanks again. Good to know the z114 is fully collumatable and has less obstruction. Would a home made collumation cap do? That's what I use for my dob. I have 10mm celestron ep that came with 60 mm astromaster LT I could lend him but I think it may be a kelner. I thought of suggesting a 7 to 21mm zoom for warmer nights. Would a 2x barlow be best? He could even unscrew barlow lens and use it on the zoom to make 4.66 to 14 mm equivalent.
2x-barlows are more commonplace. Yes, he can start with one of those, learn about it, and what it does exactly. A zoom-ocular serves primarily as a teaching-tool. Say that you observe mostly at the 16mm of the zoom over time, then you may wish to get a dedicated 16mm eyepiece.
A collimation-cap can be made with the focusser's dust-cap that will come with the kit. This is the collimation-cap that came with my 150/750...
It also acts as a dust-cap. Why, someone mentioned, somewhere, that that tiny hole in the centre of the cap provided ventilation for the telescope when stored. I have my doubts. But the one that will come with the Z114 will be a dust-cap only, I expect, and without a hole.
The hole is 2mm in diameter. It should not be larger. The larger, the less accurate the collimation. The hole would have to be drilled out, precisely in the centre of the cap, then a circle cut out from the dull side of a sheet of aluminium-foil, to be placed on the underside of the cap, as shown. The circle can be best secured with double-sided tape. Glue might be too messy. The foil will need the same diameter hole as the cap itself, both aligned as one. There should be a mark, a bump perhaps, in the centre of the dust-cap, on the top or bottom or both, from the manufacturing process, which will assist in finding the centre.
You can also take a school-type compass, describe a circle slightly smaller than the diameter of the cap, cut the circle out precisely, fold it precisely in half, then fold that in half, precisely. I can't say that enough in the doing of this -- precisely, precisely, precisely -- as you're working with something small, scientific. You then take a needle, punch a hole precisely where the folding-marks intersect in the centre. After that, flatten the circle, completely, then place it over the top of the cap, whilst centring it by noting the visible sliver of the edge of the cap all round, then make your drilling-mark.
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The Z114, a 4.5" f/4 Newtonian, is a considerably better choice over the Z100, particularly under darker skies, of which we have just now discovered.
It's important to note that this will be a first and only telescope for a beginner. The first objects at which the telescope will be aimed will be bright, and most of them small. Most any telescope is good for the Moon, so that's not a consideration whilst choosing. Thus far, I have gotten this high in power with the Z100, and at 112x, on the Moon, and with the kit's 10mm eyepiece combined with my 2.8x Klee barlow...
Not bad; but then the Moon is very near to the Earth, bright, and large, the brightest after the Sun itself. It's most easy to ramp up the power on the Moon, and still see something worth the while.
https://stargazerslounge.com/topic/341568-zhumell-z100-100mm-f4-newtonian/
Yes, there are far more deep-sky objects than those lunar, planetary and stellar, to enjoy, particularly under darker skies, therefore the greater the aperture the better, and in the hopes to see these dimmer denizens of the night, meaningfully, memorably. The 114mm aperture will be no slouch for deep-sky observations, under dark skies, and, if the telescope is well-collimated, the planets and double-stars should not disappoint, either. Incidentally, the vast majority of deep-sky objects are small, too: globular-clusters, galaxies, nebulae. But those do need larger apertures to see them well, and you can only get that with the mirrors of a Newtonian; also those of a Schmidt-Cassegrain, but I digress.
Then, at the lower powers, yea, comets!
The Z114, unlike my Z100, is fully collimatable, particularly here at the primary-cell...
That will go a long way in ensuring a proper collimation. There are springs inside that cell, of either rubber(grommets) or metal(springs). Those of metal make collimation O! so much easier.
The kit will come with two eyepieces, and the same as those of my Z100...
Those are really the only items of the kit that might be upgraded in future, over time. Plossls are economical, too, yet are performance-driven. A few decades ago they were quite expensive, but no longer. Plossls also play very well with shorter, f/4 Newtonians; for example...
...and at 50x. Combine the 9mm with a 2x-barlow, and for 100x. The bundled 10mm modified-achromat eyepiece may be used instead, but the view at that power may not be as sharp, as clear.
In addition, that 9mm would no doubt cause one to begin exploring the intricacies of the Newtonian design.
In the end, in light of newfound information, and given these troubling times, the Z114 is a very good if not an excellent recommendation.
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12 hours ago, Hugo hazendonk said:
Thanks again every one. Would a table top zhummel in the 100 to 130mm range compare in quality? It would be more in the $200Can range. It's dso as far as I know, just like skywatcher.
Short refractors and Newtonians make for difficulty in observing the planets, and other higher-power objects. Folks choose those for ergonomic reasons: easy to manage, easy to store, but optical performance necessarily takes a back seat. I have the Zhumell Z100, same as the Orion "SkyScanner", other than tube-colour and placement of the focusser. It's a 100mm f/4 Newtonian. F/4 Newtonians make for better astrographs(imaging with a camera) than for observing objects with eyepieces and the eyes.
People nowadays want their toys as small as possible, and regardless of the consequences.
I would strongly suggest not to go shorter than an f/5 for a Newtonian or Newtonian-Dobson, for the shorter the Newtonian the more difficult to collimate. Then, choose no shorter than f/6 for a refractor; the longer the better actually.
https://www.all-startelescope.com/sales/product_info.php?cPath=21_112&products_id=624
I realise that that one is over the stated budget, but I've always liked to up the ante, and for a wholesome recommendation. That kit is quite an outright steal during these troubling times.
This refractor kit might be tempting. It is without its "StarSense" paraphernalia... https://www.all-startelescope.com/sales/product_info.php?products_id=2317
Otherwise, it would do just fine without it. That would be a steal as well. Despite its smaller aperture, there would be no collimation required. Then, an 80mm aperture is nothing at which to sneeze, unless it's an ST80.
There would be a wait for that kit, new, otherwise... https://www.all-startelescope.com/sales/product_info.php?cPath=21_253&products_id=2048
This is currently everything in stock at Khan Scope... https://khanscope.com/collections/telescopes-mounts-in-stock
If you're not adverse to ordering from across the border, the pickings may be a bit better...
https://www.bhphotovideo.com/c/product/1540259-REG/celestron_22451_starsense_explorer_lt_80.html
If you'd prefer to stay closer to the budget...
The mount of that one is not ideal for that telescope, but the telescope itself is well worth the price. Most all entry-level refractors, ideally, require a star-diagonal for use at night. The diagonals usually provided are two-in-one, for that terrestrial during the day, and that celestial at night, hence they're not ideal for either.
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8 hours ago, HiveIndustries said:
I'll some day wind up with a tube 6" or tube 8" for that spot in my life...
...so I'm kind of leaning towards the 8" dob at this point.
Yes, during these troubling times, what little is available is flying off the shelves. I'm oft frustrated by that myself; not just for myself, but for many others as well.
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Yes, I've seen that one many times before. It's identical to my own, other than the colour and the position of the focusser. I got my own specifically for observing the galaxy in Andromeda, and at 13x with a 32mm Plossl. Here's the Moon through my own, and at 13x...
I would suggest a telescope with a bit more focal-length than 400mm. It's difficult to reach the higher powers with one that short. The planets become interesting at 150x and higher...
400mm ÷ 150x = a 2.7mm eyepiece, or an 8mm eyepiece combined with a 3x-barlow
The sweet-spot among entry-level telescopes is a 900mm focal-length...
900mm ÷ 150x = a 6mm eyepiece
With 900mm, you have the lowest power of 28x, and with a 32mm Plossl. By that, you can see how better balanced a 900mm focal-length can be.
Look at the secondary-obstruction of our 4"/400mm Newtonians, then that of my 4.5"/900mm Newtonian...
Secondary-obstructions cause a loss of contrast and sharpness. It's akin to a cataract of the human eye. The smaller the "cataract", the better the image quality. Needless to say, the unobstructed, albeit smaller, apertures of refractors exhibit the best-quality images.
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I'm curious as to mysterious nature of the 4" reflector. 4" reflectors are a bit rare. I have this one...
There are also the 4.5" Newtonians. I have this long-focus one...
This is a 4.5" Newtonian-Dobson, sold only by Orion... https://www.telescope.com/Orion/Orion-SkyQuest-XT45-Classic-Dobsonian-Telescope/rc/2160/p/102009.uts
There are also short ones, like that 4"... https://www.telescope.com/Orion/Orion-StarBlast-45-Astro-Reflector-Telescope/rc/2160/p/102010.uts
However, the shorter ones are not as optically performance-driven as the longer ones are.
A 5"/127mm Maksutov is "thinking out of the box" among the still-affordable kits. Maksutovs have rather long focal-lengths, and perform best when mounted on go-to mounts. They can be used on manual mounts, but a Maksutov needs a capable and reliable finder to help it find its way round the sky.
As examples, to illustrate, in the U.S., there are the Orion and Sky-Watcher models...
https://www.telescope.com/Orion/Orion-Apex-127mm-Maksutov-Cassegrain-Telescope/rc/2160/p/9825.uts
Curiously, of all the astronomical-equipment vendors throughout the world, Orion, of California, seems to be the least affected by shortages, I've noticed.
You then find a suitable mount for the telescope, for example...
Or, there is the option of a go-to kit... https://www.highpointscientific.com/celestron-nexstar-127-slt-computerized-telescope-22097?utm_source=google&utm_medium=cse&utm_term=CEL-22097&gclid=CjwKCAjw5c6LBhBdEiwAP9ejG8O_RyZ2FuYyZCixfqgsYU3Y634G0TkDjvhyQFcFPeCk1yIveY59GxoCTKQQAvD_BwE
Then, my own 127mm Maksutov is even longer than those three, and blind as a bat. I can't use a go-to mount, as I have too many trees...
Instead, I'm in the process of readying this 70mm f/4.3 refractor, and to help the Maksutov "see", to find its way round the sky...
Others make do with a red-dot finder or other.
Among the more economical kits, the manufacturers throw in a mount, and oft unsuitable for supporting the telescope that comes with it, like that long-focus 4.5" Newtonian above, within the second image. Here, I have that same telescope on a sturdier, alt-azimuth mount...
Then, the Orion 4.5" Newtonian-Dobson comes with just that, a simple, Dobson alt-azimuth base.
There is this Celestron 6SE...
That being a Schmidt-Cassegrain, and a relation of the classical and Maksutov Cassegrains.
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There is the aspect of collimation associated with Newtonians, and Newtonian-Dobsons, the latter which you are considering. The process entails a learning-curve, which your relation seems to be already set, and in learning how to collimate. The 8" is at f/6, and easier to collimate than an f/5. There is also this 6" f/8 Newtonian-Dobson...
At f/8, the 6" is even easier to collimate. It's the same length as the 8", yet slimmer due to its 6" aperture. A 6" f/8 Newtonian has been a classic choice for decades...
http://www.company7.com/library/criterion_rv6.html
That one would be the closest in ease of collimation in relation to a refractor which requires virtually no collimation at all. The construction of a refractor is tighter, rigid, with virtually no maintenance. Collimating a Newtonian has been compared to the fine-tuning of a stringed instrument, and in the playing of one perhaps.
You might also consider a refractor, a 4" for example...
That kit comes with a computerised push-to system, and for use with a "smartphone" app. That might be just the thing.
I got one these last month, and I'm very excited as to the prospects...
The kit is second-hand but in very good condition. They won't be available for too much longer. The seller is a liquidator for Meade products, and has been in business for decades.
But the refractor is permanently tethered to that mount, I'm afraid. You can remove the telescope from its mount, for storage, travelling, but it can't be used with other mounts. I'm in the process of enabling that aspect at present. It requires removal of the fittings from the optical-tube, then to add tube-rings and a Vixen-type dovetail-bar.
At that price, you could get that refractor alongside a "Dobsonian", but be forewarned, as your relation might come to prefer the former over the latter. The refractor can also be used during the day, as a spotting-scope, for birds in trees, ships at sea, that sort of thing; and in my case, for surveillance, day and night. A Newtonian cannot be used for such.
Whatever you choose in the end, I know that your relations will be beyond thrilled.
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3 hours ago, wibblefish said:
Thank you for all the info @Alan64 most enlightening! Bewildering amounts of options out there
@Tiny Clanger Yes the dob is going ti be the easier and cheaper choice but I have some weird refractor lust going on atm!
Indeed there are.
Recently, I received a totally unexpected windfall, an insurance rebate-check. Just prior, for quite some time, I had been toying with the idea of getting a 76/700 Newtonian on a yoke-style alt-azimuth, an AZ1-class...
Just a li'l grab 'n' go kit to kick, knock round and about the lay of the land. But once that rebate arrived, and combined with a bit of birthday-cash, my horizons expanded, albeit only somewhat. I then ran across this, a 102mm f/6 achromat, and it, too, on a yoke-style mount...
It was offered by a Meade liquidator out in Arizona. The seller still has them in stock, as of this writing...
O, the possibilities with that one, as a daytime spotter, for leisure(birds and ships); and surveillance even(the delinquent and nefarious), at night as well. An unobstructed 102mm aperture is simply luxurious, and bright...
You can't use a Newtonian for that sort of thing, not easily in any event.
Its short tube a pleasure to handle and stow away...
At present, I'm about to place it into tube-rings, but first I must fill, seal, the six holes left behind...
Once that's done, I may then attach the refractor onto any of my other mounts, at last. Indeed, that has been my goal all along, as I knew that the mount included was just to get the telescope up off of the ground, and little else.
At night, what a fine sweeper of the skies it will be, and with the odd higher-powered view on occasion.
Now, just imagine how much more exciting, and riveting, a 120mm or 127mm would be.
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A Restoration
in Discussions - Mounts
Posted
Forget iOptron and Vixen. I ordered this...
https://on-stage.com/products/view/11140/471270
...and from a Reverb.com seller, similar to eBay, but for that musical only, for $21.57, shipped.
We'll see how that flies.
Here are a couple of reviews I found online, at least one pertaining to that astronomical instead...
"I really had no need for the 11 lb Celestron weight and some one told me about these. They fit right on the weight bar and you do not have to remove the safety knob at the bottom to install and remove them. With the 3 lb and the 6 lb, I have all the weight I need right now, Plus they are smaller around, so you can move them all the way to the top and not worry about hitting anything on the mount. The lock knobs have a soft plastic or rubber tip, so it will not mark up the bar." - Michael
I assume that they have an "AVX", at least.
Then there was this one...
"Perfect size and weight for the Impact boom stands. No more hassles no matter how big the reflector used." - mediclimber
That had me confused, at first. All of that has to do with lighting. Of course, the rest of you probably knew that already.