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Posts posted by Alan64
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2 hours ago, Cosmic Geoff said:
"I have the same legs and spreader/tray., in white.."
Alan, that looks like a Skywatcher tripod to me, not a Celestron SE tripod. That might be a good tip about the washers though, and the spreader is identical asides from the colour. My used Skywatcher EQ-5 tripod has legs that are too loose after some idiot dismantled it completely for shipping.
My own tripod and spreader/tray are from a Celestron CG-4, identical to that of the Sky-Watcher EQ-5.
The spreader/tray is identical for the SE. Where the legs join, that appears identical, aside from the plate atop...
However, I would hope that all of that in black is of metal.
All of these tripods are made by Synta, or by one of its third-parties, overseas...
Orion, of California...
Saxon, of Australia...
...also Celestron and Sky-Watcher.
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I have the same legs and spreader/tray, in white..
The legs, once extended outwards are supposed to stop, as shown.
Then, the spreader/tray is ratcheted upwards until it stops, against all three legs...
Once that's done, if one or more of the legs loosen, outward, then there's a defect somewhere. Those legs are to come to a complete stop once evenly splayed.
Here's something I did, otherwise: where the legs join to the tripod-hub, I found these absolutely deplorable, despicable, vinyl washers, intended to take up the slack at those unions. Twelve I found, four for each leg...
I replaced the twelve, with six, rather, and of 0.008"/0.2032mm-thick phosphor-bronze sheet...
The legs now open and close as a massive door of a bank's vault. I don't even have to use the spreader/tray.
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Rather, it is understood that the images are sharper at the lower powers. This is true of all telescopes. As you go up in power, the telescope, the eyepieces, and whatever else is within the light-path, have to "work" harder to produce a satisfactory image. The telescope itself must also be collimated, as precisely as possible for the higher and highest powers.
An 8" Schmidt has a focal-length of 2032mm...
2032mm ÷ 5mm = 406x
That's a bit ambitious, yet understandably desirable. I'm a big fan of ramping up the power, myself.
Generally, an 8mm is suggested, and for the highest power, given seeing and other variables. If you're not seeing reasonable sharpness with the 9mm as well, then I'd check the telescope's collimation.
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On 20/11/2022 at 12:22, starmattic said:
Hey fellow stargazers! I am jumping back into this old thread because I am having trouble with my Orion 7827 EQ-2M Electronic Telescope Drive which is connected to an Orion 9024 AstroView 90mm Equatorial Refractor Telescope that came with an EQ-2 equatorial mount and accompanying lightweight tripod. I have read a few threads on issues related to using this motor drive, and know I am not the only one who has had issues with the motor's gear staying locked with the teeth on the RA cog on the telescope.
The only heavy-ish thing I have attached to the scope is a Pentax XW 3.5mm eyepiece which adds about 14oz/400g-ish. I have made sure my right ascension is moving smoothly and easily (including with the fine adjustment knob) and that my scope is balanced, and have followed recommendations about how lose or tight the screw needs to be that holds the motor in place, how to seat the teeth of the gears, etc.
I have come to the conclusion that the little spring that comes with the drive that keeps it engaged is just too weak. When I apply gentle pressure to the underside of the motor housing, the gears stay locked and the motor drive moves the scope without issue, even at 4X speed. If I do not do this, the motor's gear ether periodically slips (clunk! shake!) or fails completely to turn the RA cog.
Obviously I don't want to keep a hand on the motor drive housing while using the scope. As an inelegant (and hopefully temporary) solution, I have wedged a round piece of foam from the Pentax eyepiece protective tube between the bottom of the motor housing and the top of the tripod. This seems to work fine.
I hope this helps someone. All I want is for this drive to work without fiddling with it. Seems like I've found a stopgap solution but I think I will contact Orion to see if they may be able to provide a sturdier spring. I don't know what else to do.
Thank you for hearing my tale. -
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I have the same, a 100mm f/4 Newtonian...
...a Zhumell Z100, albeit off its original, Dobson base.
That at 13x, and as a marble floating in the aether.
I bought it for myself, in the hopes of encompassing the galaxy in Andromeda, at 12.5x. As an adult, I think, I regard it as a specialty, for the lower powers, astrophotographic even at f/4, not a general-purpose. A telescope needs at least a 600mm to 650mm focal-length for a sporting chance at being an all-rounder. Those first starting out tend to gravitate towards the brighter fare, the planets in particular, which require a longer focal-length, to perhaps see them as they truly are.
https://www.firstlightoptics.com/dobsonians/skywatcher-heritage-130p-flextube.html
That one may require someone older, to help. Please, help me.
This one would be most enduring...
https://www.firstlightoptics.com/evostar/sky-watcher-evostar-90-660-az-pronto.html
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There is something about a collapsible that places it into a category all by itself. It takes the Newtonian design, and for a twist. The telescope becomes more engaging, intuitive, as a result. It encourages not only a night's exploration, but also that of the telescope's interior, specifically its highly-visible secondary-assembly; the smaller mirror at the front...
As night falls, in extending the tube for use, there is a measure of satisfaction to be had in its readying for a night of awe, and wonder. If collimated well, along with a good eyepiece and barlow, strive for the higher powers, then to see for yourself what few people have ever seen.
A 130mm collapsible is not to be discounted, as it's the one that had started it all, its debut among the smaller apertures. A 130mm aperture is bright, in its own right, and portable. It's not too large, nor too small, just right rather.
But then, if you get the 130mm, you'll always wonder as to what the 150mm would've been like; particularly in that the 150mm had been only fifty pounds more at the time.
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4 minutes ago, C_H said:
Thank for your reply. Wow! That image is incredible. I didn’t for a moment think you’d be able to see objects that clearly from a telescope. What scope do you have please?
Thanks. Yes, that's a collage of several I had taken afocally.
It is Synta's(Sky-Watcher, Celestron, Orion) basic 6" f/5 Newtonian on a Dobson base, the Orion "StarBlast 6". Despite its plastic 1.25" focusser, the secondary-mirror is smaller, less obtrusive there in the centre. In hindsight, I would not have purchased it; instead, just an OTA with a 2" focusser of metal, albeit with a larger secondary-mirror, then to place it on this mount...
Once I had abandoned the base for the tripod, the telescope then came into its own, far more ergonomic, interactive, I should say. Here's a view of the Moon's surface at a rather high power...
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What a great find, and with the sun-warning label still attached to the OTA. I had gotten my own EQ5-class mount, without a tripod, a little over a year ago, and for $150. I had scavenged the tripod from my EQ3-class mount, a Celestron CG-4.
There will be the winds to consider, as the large OTA may act as a sail of sorts. A focal-length of 1000mm, nigh an all-rounder, combined with the eyepieces, the telescope will make for a fine show, with a lowest power of 31x, to 300x and more.
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11 hours ago, C_H said:
Is the 150p worth the extra £50 or will any difference be under appreciated by a beginners eye?
https://www.firstlightoptics.com/beginner-telescopes/skywatcher-heritage-130p-flextube.htmlIs it possible to find images of what I might see from each of the scopes? Have tried to look online but can’t find anything useful.
thank you!
Yes, I'd say it's worth it. I have a 150mm f/5, albeit with a solid optical-tube...
However, do you feel up to handling the largest "tabletop" on the planet? If so, have a look at this...
An increase in diameter of only 20mm may not seem like much, until you consider, rather, the increase in area.
Either collapsible would make for a fine choice.
As for images of what might be seen, I have taken several afocal shots through my 150mm f/5, of the brighter fare only...
That's exactly how those objects appeared to my eye, live, through an eyepiece.
Then, wouldn't you rather see for yourself?
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Of the BST "StarGuider" line, I'd suggest the 12mm(83x) and 8mm(125x). A quality 2x barlow, the Antares 2x for example, is also suggested, to be combined with the BST 12mm(167x) and 8mm(250x); for a useful range of powers.
Who will be collimating the Newtonian, at f/5?
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6 hours ago, cajen2 said:
I think you'd be better off with the BSTs. Also check out the Vixen NPL range - superb value for money, though I wouldn't go shorter than the 20mm, as eye relief becomes a problem. I used a 30mm as my wide-field EP for ages and it gave very respectable views.
It is a shame, that, as the eye-relief of my Vixen NPL 6mm is very tight, yet I can use it well enough, and the views rival that through my BGO 6mm.
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I just don't know, the collapsible. It's a bit reminding of the wild side of the 1960s, of life transient perhaps. It does have that charm, albeit not its best feature to consider, but I feel that it would be more engaging for the user. Rarely has such garnered so much attention.
Both the collapsible and solid-tube variants could be transferred to a tripod-mount, an alt-azimuth still, in future perhaps...
Although, the collapsible's balancing on such might prove difficult.
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This is my own variable-polariser...
What my eye saw with that one integrated, on Jupiter, and during a brief, clear window through our atmosphere. I'll never forget, the festoons and whorls.
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9 hours ago, stephec said:
Thanks Alan, I'm familiar with polarising filters in photography, but would a standard moon filter do a similar job in this case?
For fixed examples...
50% reduction: https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-125-nd96-0-3-filter.html
75% reduction: https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-125-nd96-0-6-filter.html
87.5% reduction: https://www.firstlightoptics.com/moon-neutral-density-filters/astro-essentials-nd96-0-9-1-25-moon-filter.html
All three may be had, if uncertain as to the one required.
Do you look upon a variable-polariser as being gimmicky? I have, at times.
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The "Heritage" 130P is also available in the U.S. Either/or...
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In so far as this one...
https://www.telescope.com/Orion-StarBlast-102mm-Travel-Refractor/p/132065.uts
...I think that I have the same configuration, my Meade 102mm f/5.9 achromat...
...?
Orion, of California, states within its specifications that it is a 102mm f/5.9 achromat, too. Although, I have my doubts, as that of the Orion kit appears to have a somewhat shorter optical-tube; minus the focusser, the lens-cell, and the dew-shield...
Strange, that; the Orion 102mm looks to be at f/5 rather, and with oodles of false-colour to be had. I wonder if you know what false-colour is, chromatic-aberration. I'll show you what it is. When you point the telescope at a small bright object, like a planet or star, with a fast-achromat like that Orion, if indeed at f/5, instead of seeing the object clearly, it will be smeared somewhat, and with strange, unnatural colours...
https://www.youtube.com/watch?v=WANNqr-vcx0
Another unpleasant thing is that it comes, not with a 2" focusser as expected, but a 1.25", instead. It may also be of plastic. I wouldn't be surprised. That of my own is a 2", and of metal.
In the end, run away from that one.
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The Zhumell Z130, if a solid-tube is desired, or the SW "Heritage" 130P if you prefer its collapsible feature.
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In 1941, then the USSR, a group of scientists were hurriedly boarded onto a fast train headed east towards Siberia, and to protect and secure them from invaders encroaching from the west. On that train, with papers in his lap, was Dmitry Maksutov, an optical engineer, also an amateur astronomer as ourselves...
Maksutov had a beautiful, wonderful reason for creating his telescope: for schools, school-children, and to withstand the rigors of that environment. Among all reflectors, which utilise an objective mirror, a Maksutov is the most refractor-like, in tight, durable construction and optical performance. This is how light from an object travels through a Maksutov...
The incoming light is folded twice, into three paths. That's how to fit a long focal-length into a short, compact tube.
The suggested 102mm Maksutov has a focal-length of 1300mm, and simulates a 90mm+ refractor, yet the refractor would have a very long tube by comparison, cumbersome, unwieldy, requiring a large, heavy and costly mount to support it. Although the 102mm Maksutov can be placed on a lightweight photo-tripod, and be well supported, but a telescope-type mount would be best, like the equatorial mount within the kit's listing. I do wonder if that mount can be used as an alt-azimuth. It does appear that it might.
Given that Maksutov's long focal length, it will play well with inexpensive eyepieces, even like this free kit-eyepiece of my own...
That one, at 4mm, would realise a power of 325x. However, the telescope, combined with our atmosphere and other variables, may not be able to reach that high of a magnification. Eyepieces, in general, range from a high-power 4mm, to a low-power 40mm.
To assist the user and the telescope's finder in finding objects to observe, it's best to have a lowest-power eyepiece on hand, which could be a 40mm, but in general a 32mm Plossl is used. A 40mm Plossl will show a slightly wider view over that of a 32mm...
That's it, the lowest power, and the widest view, to help with the hunt, but a bit of a narrow view when compared to other telescopes. Maksutovs are not for wide, panoramic, low-power views, but it will take you in the opposite direction, up close to an object, at high power, then to see what most people have never seen.
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On 13/11/2022 at 11:57, stephec said:
Trying to look at Jupiter a few nights ago with the SR4 was what prompted this post, I could see the colour bands but not focus sharply on them.
I have a 150mm f/5 Newtonian. Is your telescope collimated? It will need to be at the higher and highest powers. Also, Jupiter through a 4mm, at 188x, can still be a bit bright, whitish, which can conceal the planet's features. I use a variable-polariser, to dim the view a bit, then to see the planet's features more clearly....
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I have one of those kits, branded "Zhumell": a 100mm Newtonian, and at an astro-photographic f/4 if so inclined, but I use my own for strictly visual observations...
I had gotten the kit for a sporting chance to see the galaxy in Andromeda at its most encompassing, at 12.5x, but I've yet to attempt it. The Pleiades may certainly be seen in its entirety this winter, and Orion.
A 32mm Plossl(12.5x) is desirable, for all telescopes at that, for the lowest power and widest view; but not a 40mm, unless for a special need of which I'm not aware, although a 40mm would produce 10x with the telescope, like that of a binocular. The Moon through my 30mm Plossl at 13x...
At the other end of the magnification scale, I then took the kit's 10mm eyepiece, inserted into my Klee 2.8x barlow, and for an effective 3.6mm eyepiece at a power of 111x...
Those are afocal-shots only, through this eyepiece and that, taken on the fly with a small point-and-shoot camera.
The telescope is unique at 100mm, for a Newtonian, and bright in its own right.
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Ken, there is a great, a greatest benefit actually, in the image being inverted with open-air reflectors, like Newtonians, and our catadioptric-reflectors. I have a 127/1000, just the next size up from your own. Both are known, colloquially, as a "Bird Jones" telescope...
Ours are loose interpretations, knock-offs of the original design, and from the 1940s.
The benefit? Open-air reflectors are not suitable for daylight, terrestrial observations, hence they are not likely to be outside when the Sun is up, therefore little to no chance of one being accidentally pointed at same; for safety.
Our catadioptrics are infamous, notorious, for being particularly difficult to collimate, when compared to classical Newtonians. I got mine collimated. I hope yours is, too.
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Hello, and welcome Ken.
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I take afocal shots of this here, and that there, on the fly with a point-and-shoot camera steadily held up to an eyepiece; the Pleiades through my 150mm f/5 Newtonian...
M13 in Heracles...
Celestron Nexstar 8se tripod issue?
in Getting Started Equipment Help and Advice
Posted
It's good to hear that you've resolved the issue. Will you be imaging with the telescope?