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Alan64

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Posts posted by Alan64

  1. The AWB "OneSky" is the same kit, made by Synta.  There is this long-running thread within Cloudy Nights...

    https://www.cloudynights.com/topic/463109-onesky-newtonian-astronomers-without-borders/

    It has a great following.  At that price-point, you can't go wrong.  But as with all entry-level kits, and advanced ones as well, there are pros and cons.

    But ignore that, as 130mm of aperture is a wonderful thing, and the telescope's 650mm focal-length will enable you observe the gamut, everything in the sky that the aperture will allow; with the aid of 2x and 3x barlows.  Collimation is not all that difficult at f/5.  I have a 150mm f/5, and it hasn't been too difficult.  Then, there's its compact size, ready to go at a moment's notice.  It has a stalk-type secondary rather than a spider-type, and I've found that to be preferable whilst observing with  my 114mm f/8...

    kit3a.jpg.9007218034142685162f43dfbb521beb.jpg

    It's nigh near a modern Cassegrain's configuration in that.

    The main complaint of the AWB "OneSky" is the helical-focusser, and that of the "Heritage" in consequence, but it's not inside the tube, and can be adjusted with a bit of DIY.

    The tube is removable, and can be placed on a tripod-type mount in future, for improved control.

  2. This 90mm Maksutov upon my larger alt-azimuth, fell over one day.  The telescope itself did not hit the floor, as the girth of the mount prevented that...

    1c.jpg.d973a2f3d7c3246a73dcf5816e9fa71d.jpg

    It's not my own, a relation's, but I'm the only one who has used it in an astronomical manner.  I don't know if it's out of collimation from the factory, or as a result of happenstance, but it is off a bit according to my collimation-cap.

    There are instructions online, and the process akin to a Chinese finger-puzzle for those who have yet to attempt the procedure, including myself.  But I feel responsible in this instance, so I get to have some fun.

    Of the three mirrored designs of telescopes commonly encountered within the marketplace -- Newtonians, Maksutovs, and Schmidts -- the Maksutov is the most difficult to collimate, with the Newtonian running a close second.  A Schmidt is not necessarily a cake-walk however, but is the easiest of the three.

    If you have a 1.25" diagonal that came with the kit, and are wanting to replace it with another 1.25", I humbly suggest a star-prism, rather than a star-mirror(dielectric), like this one...

    https://www.365astronomy.com/Celestron-Diagonal-Star-1.25-in.html

    The Lacerta appears identical, but I would write or telephone first to ensure that it is in fact a star-prism... 

    https://www.365astronomy.com/Lacerta-Star-Diagonal-1.25-inch.html

    Then there's this one, and not for too terribly much more than an entry-level dielectric...

    https://www.firstlightoptics.com/diagonals/takahashi-125-diagonal.html

  3. 2 hours ago, Alexandros said:

    Ahhh, that's uplifting Alan! (Not the dream part, that sounds like a nightmare to me 😋 )

    While I am by no means gonna risk exposing my scope to water, I am very relieved that if I get a bit of water in my scope I can clean it and be good to go!

    Thanks a lot! :)

    Newtonians can withstand that sort of thing; a refractor however would not fare as well, nor a Maksutov or Schmidt.

    • Like 1
  4. 1 hour ago, Alexandros said:

    Hi Alan! Thanks for you response. 

    I am not familiar with the criterions you mentioned but I'll look them up. 

    Regarding the mount. Mine was in fact tight and quite difficult to move in the RA axis with the handle on, but I applied some WD-40 to the contact of the main gear with the worm shaft and it became a bit better and the motion was smooth. However, I am not able to move it with my fingers when I'm trying to twist at the position you pointed in the picture. I assume a loosening up is called for. I will search for a tutorial for how to do this properly, but if you are aware of good one, could you post it here so I can have a reputable one? 

    Thanks again for responding

    Alex

    There are only three areas of these entry-level mount-heads, in this instance the EQ-2,  that need checking, and oft adjusting upon its arrival...

    1.  The RA lock-nut...

    1460070215_RAlock-nut8.jpg.4bb04cfb95de4e29e2c8f66aa80f8574.jpg

    You would simply loosen that one to adjust.  Being a lock-nut, it will hold its position wherever you set it.

    2.  The DEC lock-nut...

    1012712135_DEClock-nut5.jpg.3f112e4fcf0e176e8bc756f536fa73af.jpg

    You would loosen the three screws round, screw the ribbed nut inward or outward to the desired position, then secure the screws.

    3.  The RA worm-shaft assembly is a bit more complicated, but it's not that difficult really...

    https://stargazerslounge.com/topic/319273-meade-large-equatorialeq-2-hyper-tuning/?do=findComment&comment=3492379

    At a minimum, there should be no dire need to completely disassemble anything.  You want those junctures to be without slack and slop, yet easily set in motion.

    For the lack of a better analogy, these entry-level mounts, and those larger even, are oft as this upon arrival...

    https://www.completelydelicious.com/wp-content/uploads/2015/01/IMG_4124.jpg

    ...a work still in progress.

  5. Glamour shots...

    725689490_woodentripod11.jpg.4541815ad20eacb82309e37a01d441f2.jpg

    I couldn't be more pleased with the outcome.  The unions throughout are wonderfully rigid and tight, yet requiring little effort to set them into motion...

    1049193833_woodentripod12.jpg.6922f4ac9933fa860690edfc5b15ff9c.jpg

    1060464410_woodentripod15.jpg.d0f8ce67cf573b12c58d775ce9f9217d.jpg

    I don't think that I'll ever extend the legs farther than that.  I may even install stops, and as my larger wooden tripod had been originally equipped, but something a bit more effective than just screw-heads.

    1789497519_woodentripod14.jpg.7c04ecd3de3cac0ca8bc8cdb64d44fd3.jpg

    I now have a can of Diet Coke® as my new prop; for perspective, a sense of scale.  Just how small is the tripod?  

    1322513182_woodentripod9.jpg.478db61070fcbe06066d299a1fee902e.jpg

    I am toying with the idea of a pier, but perhaps not quite 8"(20cm) in height as two of my other mounts possess; perhaps 6"(15cm) instead...

    988758601_woodentripod10.jpg.0c0b5c0563f374f5e7188ef5acaef9f4.jpg

    Now to finalise the mount-head.  I'm also waiting on a 5"(13cm) anodised-black dovetail-bar from China for this mount's telescope.  I just can't and refuse to use this one...

    sealed2.jpg.d6f9829052abf84a6442870f3852c0c3.jpg

    ...that from a modern Meade achromat.

    • Like 6
  6. Done...

    spreader14.jpg.9a854b12878ffee0d29677298f3e6d3a.jpg

    One last hurdle to overcome, and where the pins of the old hardware were removed, as the threaded holes of the lock-nuts rose above the ends of the screws...

    spreader15a.jpg.3dcccf2947521274111f8f58f6c55ae9.jpg

    What to do about that?  Where there's a will there's a way. 

    I simply ground down one of the six flat sides of the lock-nut until it lowered into position...

    spreader19a.jpg.7c49b33fca8682bd7661e4b9b85b0950.jpg

    Also, the diameters of the screws' heads required reducing, and to clear the surface of the braces as they slid into place.  You can see there on the right where the paint had been scratched before.

    Gone is that ubiquitous slack and slop that plagued these older mounts(the current ones as well), and right up to the eyepiece of a telescope...

    spreader18.jpg.1a1fc3646ecbb159548067ea4c5e9a67.jpg

    The lock-nut for the larger screw is a good bit thicker.  I couldn't find jam-type lock-nuts for that size, only for the smaller as seen.  They are available online however; perhaps one day.  Lock-washers instead of flat-washers were integrated with the lock-nuts, and for peace of mind.

    Done...

    spreader21a.jpg.94ad7162d9675169af1a92fafd797dec.jpg

    • Like 2
  7. I had a hiccough, and a fortunate one...

    1460701069_spreaderpoints2.jpg.d9fadae131d4bd2816588f0c75bf4aa5.jpg

    Well, would you look at that.  The attachment points differ in position. 

    I've got to know how exactly where to attach the braces' tabs to the arms of the spreader, and so to preserve the same angle of the wooden legs as those of the aluminum when folded outward, or near enough.

    I then made a diagram with my old "CAD" programme, Paint Shop Pro 6.  I tried version 7, long ago, then went back to 6.  When you've already got a good thing going...

    1947103842_legangles3.jpg.34e0f878e6f4cf487f3f03590d930a6f.jpg

    The arms of the spreader must be somewhat longer.

    From that, there, and indeed near enough...

    575930120_legangles2.jpg.df78eb6006fca8e1848a38c8c9c12cb2.jpg

    ...or 25.4mm.

    <hiccough>

    • Like 1
  8. The most challenging aspect of this part of the project was in the marrying of the old hardware of the wooden legs to the spreader-assembly of the much newer kit.  I removed the steel-pins of the old braces, then went to my local hardware...

    tabs2.jpg.e79f3bd25917443e1bded614c888acd2.jpg

    237924600_spreaderfix2.jpg.3a1688bb32bea697e3e8a4665a926432.jpg

    After I set to work from there, I realised that the loops at the ends of the arms had to go...

    spreader4a.jpg.7c54e42f954fc27c7ff8a095c1070a77.jpg

    The ends were hammered flat and smoothed.  You can see there at upper right where I needed to batten down a lock-nut, yet the loop was in the way.  Scoring with a diamond-wheel, then a hacksaw, removed them rather quickly.  As a result of using said tools to prepare these parts, a nick here, a scrape there, all got a fresh spritzing with satin black, and to prevent rust...

    spreader10a.jpg.42721530d93fe840562aa78abc7660f9.jpg  

  9. Springtime chores had placed this project on hold for a spell -- milking the cows, repairing the ox-cart and the stone wall round the homestead -- those sorts of things.

    The new-old legs finally received their first coat of satin spar-urethane...

    1434496738_woodenlegs17.jpg.c4994fbd5edc076aa9e8fc45d4993b63.jpg

    ...then a second coat on select areas, and where wood does not contact wood...

    1986886583_woodenlegs18.jpg.751eb34c69f55ea9107b55023c317cd8.jpg

    After the varnish cured, brass was placed on the tops of the center-legs, and to protect the wood when slammed up against the edges of the yokes of the tripod-hub...

    161724375_woodenlegs19.jpg.9422909ea6ff404fb495cdf4045ac84e.jpg

    1570509089_woodenlegs20.jpg.1439e338d2d50b49a159395ce44ebc0e.jpg

    I considered aftermarket tips for the legs, but upon closer inspection, and after a trip to town, the original tips will be fine.  But instead of re-stapling them, I decided to secure them a bit better...

    1466807296_legtips2.jpg.34c5dcf132bcfb5c7a03c178231f4958.jpg

    ...and of stainless-steel.

    • Like 2
  10. After a "wild" early-morning session, I left the tube of this Newtonian outside pointed straight-up, at the zenith, then went to bed...

    1356273375_6f5ba.jpg.8621dfa4a1071c0eac19db0c4d30f125.jpg

    I dreamt during that time, and of going outside to find the telescope full of water.  In the dream, I must have poured a couple of gallons out.  Upon awaking, I went outside, and it had indeed rained whilst I had slept, but there was, at most, only a tablespoon or two of water within, and with no harm done.  I took the telescope inside, blotted what water I saw, allowed it to dry, then all was "right as rain".

    • Like 2
  11. 16 hours ago, Alexandros said:

    Thanks a lot Cosmic!

    Thank you for that final remark, I was under the impression that all the mirrors were parabolic. Now I am much more cautious as to what I should invest in. It could very well be the reason why there seems to be a deadzone in the focus of my scope, within that window, the sharpness of the image does not improve. Is there any way I can test if the spherical mirror has a noticeable effect? For example if there is a certain lunar feature I should be able to distinguish, or a binary star I should be able to split, or something else.

    I also see from your post, that you have the EQ 5 mount and the motor drive for it. Could you share your opinion on it? I saw it today online and was thinking if I should consider it for a future upgrade.

    You have a Sky-Watcher(Synta) 130mm f/7, and I have this Meade(Ningbo Sunny)114mm f/8...

    kit4d.jpg.168b14e59b201a9548c2db265f2bda95.jpg

    Both of our telescopes have a 900mm focal-length, an EQ-2 mount, and spherical primary-mirrors.  At the longer focal-length of my own, I have been told that the telescope is at 1/5th-wave if perfectly spherical.  Therefore yours, at f/7, should perform within Rayleigh's 1/4th-wave criterion as well, and diffraction-limited.  But it must be collimated well.  Mine, fresh out of the box, gave me practically tack-sharp views.  

    "Diffraction Limited" is stated within the specs of the Orion-of-California variant of your own, the Orion "SpaceProbe" 130, and also made by Synta.

    In order to use an inexpensive motor-drive with your mount, you must adjust the mount, and to where you can twist the RA worm-shaft with your fingers, and with little effort...

    504154131_twisthere.jpg.1bf97d460b5902cfdfde7d83e4e7b5dc.jpg

    Else, the plastic gears and their teeth within the drive will break and crack, and the motor itself can burn out.  These mounts generally arrive bound-up and tight.  If yours seems a little too tight, loosen it up.  The mount is a mechanical thing, a machine, and consisting of nuts and bolts to hold it together. 

    • Like 1
  12. It appears that you know and prefer the Maksutov design, therefore barring the acquisition of a 250mm...

    https://www.robtics.nl/popup_image.php?pID=3005

    ...and in that you already have a 120mm, I would go with the 180mm.  A 150mm may not give you the "pop" you're looking for after having observed with the 120mm. 

    I've always believed in placing the wherewithal at hand into the telescope, then to to get the bits and bobs for it over the weeks and months, and years even.  

    I prefer Maksutovs over Schmidts, and will be getting my own in future.  

    • Thanks 1
  13. Incidentally, I found this 90mm refractor at a thrift store recently, and in dreadful condition...

    1550803670_MeadeDigital.jpg.3aa63747998fbf57f91bdef10c6440bf.jpg

    No hand-controller, and busted up right good.  I couldn't even rack the focusser in and out, as it was much too loose, like it was going to fall apart.

    588061373_MeadeDigital2.jpg.faee17fb141dfdbb6765842587280265.jpg

    I don't want to know how that had happened.  The price-tag...

    1187742700_MeadeDigital12.jpg.cf3ded66f135dee751647ab515cee167.jpg

    Well, at least they wrote "Refracting Telescope" on the tag.  I'll give them that.

  14. 21 hours ago, rwilkey said:

    Apologies Alan, I was going by the given sizes in mm (of the eye lense) in the actual advert and projecting up.  Is this not the eyepieces that come with the scope?

    I see what you're referring to, and understandable, but could the 22mm and 11mm be referring to the eye-relief instead?  Granted, that would be odd in their including that information.  Much mysterious, but after investigating further, an Amazon member answered one of the questions posed about the kit, here...

    https://www.amazon.com/ask/questions/asin/B017NHHZ4G/3/ref=ask_ql_psf_ql_hza?isAnswered=true

    "Yes, I got the Celestron 93230 8 to 24mm 1.25 Zoom Eyepiece, it works well with the scope as well as the Barlow Lense. Haven’t had any problems with it at all, and it’s very convinient not having to swap out lenses for different magnification. Highly recommend." - William Bartnik

    Now, I have seen new kits online bundling .965" eyepieces, in the past few years, but thankfully very few and far between.

    Incidentally, the Zhumell .965" oculars are defunct.  These are the only decent ones I know of sold new in the U.S., and I have two of them myself...

    https://optcorp.com/collections/0-965-eyepieces

    • Like 1
  15. Any eyepieces or accessories(like a star-diagonal or a 2x barlow) that are purchased for the present kit can be used with other telescopes that may be acquired in future.  

    Telescopes come and go, but eyepieces and such are like luggage, and for life.  When you buy a 2x barlow, it's a one-time acquisition.  You'll never need another, unless they're lost or spirited away.  The same goes for the rest.

    I, too, suggest a star-diagonal, for use at night, and a 32mm Plossl(22x).  The 32mm would provide your lowest power and the largest view of the sky; to get your bearings, and for the ease in hunting for this object and that.  Once an object is found, you may want a closer look at it.  You then swap the 32mm with a 12mm(58x) combined with a 2x barlow, and for a simulated 6mm(117x).  That would be about as high as you might go, for now.

    Examples of same...

    https://www.365astronomy.com/32mm-GSO-Plossl-Eyepiece.html (22x)

    https://www.365astronomy.com/12mm-GSO-Plossl-Eyepiece.html (58x)

    https://www.365astronomy.com/GSO-2x-Barlow-2-Element-Achromatic-Barlow.html (117x, with the 12mm)

    If the budget will not allow, a barlow can wait.

    A star-diagonal... https://www.365astronomy.com/Celestron-Diagonal-Star-1.25-in.html

    The word "star" tells you that it's for use at night.  The original diagonal that's missing is an Amici, or erect-image, and for daytime/terrestrial use; birds in trees, ships at sea, that sort of thing.  Replacements of that type are sold online as well.

    If you only want to "jump start" it, there are budgetary options for everything but a 32mm Plossl, on eBay and the used marketplaces online.

  16. 11 hours ago, Anthony1979 said:

    Wow... I think i would need a lot more experience before i do anything like that plus the scope is new so i dont really want to be messing around with it 

    Quite right, as you want to have experience with the telescope and its workings beforehand.  It was a year of observing before I began my own.  You would be without the telescope during the renovation, of course, but then you'd have the improved views of which to look forward once it's completed.  In addition to the flocking, I use matte, chalkboard-black spray paint, and I sometimes spray the paint into a condiment lid or other and apply the paint with artists' brushes, when applicable.

    Within my link posted previously, I later abandoned the idea of flocking the drawtube of the focusser.  Its interior might need to be repainted however, if desired, and upon inspection.  The "black" paints used by the manufacturers are nowhere near the blackest available.

    The goal is to make the front entry and the entire interior of the telescope up to the eyepiece as inhospitable to stray reflections of light as possible.

    If I had to go back in time, and before my own was performed, I wouldn't observe with it until after I did it all over again.

    • Like 1
  17. On 02/05/2019 at 19:55, Anthony1979 said:

    Wouldn't this mean i would need to take the spider part off

    Actually, you'd need to take the Newtonian completely apart, for a proper job.  Ah, but no more ghosts and goblins within the field-of-view.  When observing an object, the contrast would be noticeably improved, to see its details more clearly, and the background sky surrounding the object would be blacker, instead of just grey-black.  Have a look at what I did to my own...

    https://stargazerslounge.com/topic/262096-deadening-a-150mm-f5-newtonian/

    Any questions?  I'd be glad to help.

    • Like 2
  18. 23 hours ago, Anthony1979 said:

    Thanks.... And little ticks coming of them... Its weird

    Ah, those may due to ghosts and glares, those in turn caused by reflections along the light path, whether within the eyepieces, a barlow if applicable, or the telescope itself. 

    Have you ever heard of blackening and flocking the interior of a telescope?

  19. On 29/04/2019 at 14:45, Anthony1979 said:

    Thank you for all your assistance.... When i looked at a bright star through it it had spickes coming from it

    Yes, that's due to the lovely spider-vanes supporting the secondary-mirror, just inside the front of the telescope...

    spider-vanes2.jpg.37f15631c82d77897a48ad48fa612c42.jpg

    It is possible to minimise, perhaps to even eliminate the effect, and with a single curved vane...

    https://garyseronik.com/how-to-build-a-curved-vane-secondary-mirror-holder/

    With my own 150mm f/5, it's particularly annoying when observing Jupiter, or Mars during its last opposition, but a variable-polariser works a treat in those instances, and perhaps for the brighter stars as well...

    https://www.365astronomy.com/variable-polarising-filter-1.25-by-ovl.html

    The object will be dimmer, of course.  In the case of Jupiter I was finally able to see the planet's features with the filter integrated.

     

    • Like 2
  20. You can take casual snapshots through any eyepiece and through any telescope, but only of the brighter objects in the sky, and with a small point-and-shoot camera, or with that of a so-called "smartphone".  I took these, shown here within a collage, simply by holding said point-and-shoot up to the eyepiece and snapping the shots...

    sampler.jpg.01155e716171f8421e570491c6cc8024.jpg 

    That's just how each appeared during a live view, with my eye and eyepieces, and through this 150mm f/5 Newtonian whilst mounted onto that alt-azimuth...

    166066086_6f5ra.jpg.014ce0553d9e34b14bced41a0c32f99a.jpg

    Of course, the objects looked much better during the live view, with my own eye.

    But if you're wanting to take pictures with a camera attached directly to the telescope, that will require a large, heavy and substantial tracking-capable mount, along with a smaller telescope; for example...

    https://www.firstlightoptics.com/reflectors/skywatcher-explorer-130p-ds-ota.html

    https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-eq5-pro-synscan-goto.html

    But if you considered that mount, this one would be better in the long run...

    https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-heq5-pro-synscan.html

    This one, even better than that one, perhaps... https://www.firstlightoptics.com/skywatcher-mounts/sky-watcher-heq5-pro-with-rowan-belt-mod-upgrade.html

    That kit would be a bit overkill for visual use, also with a smaller aperture to boot; but for astrophotography it's at a minimum.

    Read about what you might accomplish with a 130mm f/5 Newtonian... https://stargazerslounge.com/topic/210593-imaging-with-the-130pds/

     

    For visual use only, a Newtonian on an equatorial mount is for longer periods of observing a single object.  The mount, if simply motorised, can also cause that object to stand still there in the eyepiece, and as if time itself had stopped.  If you prefer to flit from one object to another in the space of 15 minutes or so, then choose an alt-azimuth mount.

    Your eye and mind isn't really bothered if the image in the eyepiece shakes and jiggles, but a camera attached in place of your eye and eyepiece simply will not stand for it, and will result in blurred images.  A camera must be held firmly in place, like a rock, when tracking a dimmer object over a long period of time, whilst collecting the light from same, or else just one little shake or jiggle will ruin the image.

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