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Showing results for tags 'reflector'.
Found 35 results
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Hope someone with more experience than I, which basically means anyone that has successfully collimated a Newtonian, can answer a couple of compound questions I have based on my first and only attempt at secondary collimation of my SkyWatcher Flextube 250. 1) All three of my secondary collimation screws were extremely snug before I did anything and I was only able to comfortably turn them counter-clockwise. Is this normal? Do I need to loosen all three screws first before I can properly start collimation? Should I be turning any screw beyond "snug"? 2) Before collimating, I placed a yellow sheet inside my OTA opposite my focuser tube and I placed a red sheet between my secondary and primary. The view this gave through my focuser tube was of a red circle surrounded by a partial yellow ring (the secondary mirror stalk blocking a portion of this yellow annulus). While independently turning each of the secondary collimation screws counter-clockwise I looked down the focuser tube (both with and without a sight tube installed) expecting to see some change in the shape of the red area (more or less circular) and/or the yellow area (less or more even thickness). I turned the screws no more that 2 complete revolutions. I did not perceive any appreciable difference in what I saw and I turned each screw back (clockwise) to their original tightness before working with another of the screws. Does it make sense that I didn't perceive any change? Should I have turned the screws more revolutions? Should I have loosened more than one at a time? Very confused and looking for your help. Thanks -
Hello folks, for long I have been browsing the internet to find a suitable 10in dob and despite lack of reviews, I have decided to take the plunge with the Bresser Messier 10in Dobsonian. There was some doubt at first, especially when considering the popularity of similar scopes from Skywatcher, Meade and GSO. Even though Bresser is relatively new to the market, it has some clever features: 1. The massive 2.5in hexagonal rack and pinion focuser is very solid and the movement is smooth. Despite being only single speed, Bresser sells an a dual speed 10:1 extension. However, I find the movement precise enough and do not need the extension at the moment. 2. Optical finder scope feels a bit cheap but it is a nice upgrade over the red dot finder I had on my previous scope. 3. Rocker box style base allows disassembling the scope into two pieces (OTA and base). 4. Tube rings allows the scope to be easily balanced when adding weight + after adding a suitable dovetail plate, the OTA can be used on an equatorial mount (if you plan to upgrade to an eq mount, I would consider the 8in model, as an eq mount for the 10in would be expensive). The only negative comments I can give about the scope is the production process. There were some minor issues with the assembly with the scope as parts did not fit properly. First problem was with one hole drilled deeper (loosening the particular screw fixed the issue). Another problem was with the altitude wheel as it made the OTA to pop out from the rocker box. (A loose screw on one of the plastic pads between the box and altitude wheels was causing this. Make sure all these screws are tightened and below the surface of the pads). Lastly, I assume there must have been a mistake in the quantity of items included (I got twice as many screws for the rockerbox and 2 eyepieces instead of one, both were 25mm super plossl but the standard was a 1.25in advertised on the bresser webpage, while the other was a 2in wide angle) I did not have the opportunity to test the scope outside properly due to clouds. Update: 01.06.2017 Had the chance to try it out on the moon and jupiter to a max magnification of around 160x. The results were very sharp and detailed views. Unfortunately, clouds rolled in before it got dark enough to observe DSO's. I am waiting for clouds to clear and a package with a 42mm wide angle eyepiece and a 2in GSO 2x ED barlow to arrive next week.
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Hi! I am very new to SGL (just signed up a couple of mins earlier) and to astronomy as well, though I have been facinated with celestial bodies since I can remember. I recently purchased a Celestron Powerseeker 127EQ but now I’m having troubles using it and I can’t seem to see anything through it. I also have a Celestron collimating eyepiece but I still can’t seem to make it work. Anyone here who has experience with the same scope? Would appreciate if we could chat a bit as I would be really interested in your experience and how you ultimately made it work!
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I recently had to move from my residence and amongst the items in my store was the first telescope I had ever used. It as a Celestron FirstScope 114 that is no longer in production, a 4.5 inch f8 classic newtonian. Unlike the current model PowerSeeker 114, it has a EQ2 mount rather than an EQ1, and a red dot finder instead of the unusable 6X30 plastic unit on the PowerSeeker. So after probably a dozen years since last using it I decided it might be interesting to put it through its paces. I fondly recall seeing things like the polar ice cap on Mars at opposition, the GRS spot on Jupiter, the Cassini Division on Saturn and some deep sky objects like M7, the Double Cluster, the M81 M82 pair and a lot of more with this scope. After using a CPC 1100 almost exclusively since, I wanted to confirm to myself that I had really seen those object through the scope. The carton it was packed in was not completely sealed so it was covered with a great deal of dust. Looking down at the primary I could see some dark smudges - I didn't know if it was dirt or deterioration of the aluminum coating but luckily very little dust. I decided I would try the scope out before attempting to dismantle and do anything with the mirror. I cleaned it up the best I could and assembled it with more difficulty than I recalled having in the past. I used to keep it fully assembled with the latitude set at 9 degrees, the counterweight midway between two of the tripod legs and set it down with the polar axis roughly pointing North. I found that this way a could track an object with the RA slow motion control with only occasionally having to adjust the Declination. I tried to do the same this time but was constrained by having to set up on a narrow balcony rather than on the open ground. After having to wait a few day for the unseasonal clouds to clear (It looks like the bad weather issue also applies when you resurrect an old scope?) first target (Drum roll!!!) Albireo which was high up in the eavening sky. I had difficulty finding the target - I guess it was too much to hope that the battery in the red dot finder would still be alive after a dozen years. Using a 20mm eyepiece that came with a Celestron 102SLT I anxiously searched around and after a few minutes located the unmistakable colorful pair. Encouraged I switched to a 9mm eyepiece from the Celestron Eyepiece and Filter kit - and I must say I was pleased. At 100X the image was sharp and somewhat surprisingly, the collimation seemed very decent. The big difficulty was the stability of the mount. A touch of the slow motion controls would start it shaking, taking maybe 5 to 7 seconds to settle. Focusing was the real challenge. I would make a tiny adjustment to the focus wait for it to settle then try again till I felt I had achieved the best possible. That was all I had time for the first evening and packed up not too disappointed. A couple of days later I had the scope out again. I first tried Jupiter low down in the SW. The seeing was bad but I could clearly see the two equatorial bands and three moons. In the past I had used the 4mm eyepiece from the above mentioned kit for a magnification of 225X. There is a 2X barlow in the kit but I had wanted to use the minimum amount of glass possible. This time I used the barlow with the 9mm eyepiece from the same kit for a magnification of 200X but with a more comfortable eyepoint. When the seeing was more steady for brief moments I though I could see some structure in the belts. My next target was Epsilon Lyrae - the double double. After some difficulty finding the pair and battling with the focuser, I had a rewarding view with both pairs clearly separated at 200X - nice airy discs (almost points) with some hints of diffraction rings. And finally for the pièce de résistance, I turned my scope to Saturn about 50 degrees above the horizon. With the 32mm eyepiece the rings were obvious. I carefully changed to the 9mm barlow assembly and frankly was amazed! The Cassini Division was in your face visible - no challenge at all. I felt the coloring of the bands on the planet was move vivid that through the CPC 1100. I could clearly see the shadow of the planet on the rings. Titan was visible with direct vision. The view was crisp to the extent that I thought it could take more magnification. With the CPC 1100 I once had the magnification up to 400X and though I could see the Enke gap as a darkening in the outer ring - but the FirstScope does not break your budget or your back! In conclusion I remember reading a review of a 4.5 inch newtonian (I think in was the Orion XT4.5 Dobsonian) and the reviewer mentioning the apo like views given by the diffraction limited spherical f8 primary. Having never had the chance to look through an apo refractor I can't confirm either way but clearly these cheap reflectors are nothing to sneeze at. Were it not for the unsteady mount I would have loved to continue using this scope. I imagine this scope but on a good quality altazimuth mount would make a very good beginner instrument. Hopefully I can pass it on to a youth who is passionate enough about astronomy to tolerate its quirks as I did and put it to good use. Thanks for reading!
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bit more from a frosty last night c gem pier in obsy sct 9.25 hd 720* logitech some colds hands and i did some other stuff will sort later but for now enjoy these close ups sit at least 3 feet away from yor monitor please to get the full beauty of the moon pat
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I have acquired an old 1960s Newtonian telescope which I am reconditioning as part of my STEM Ambassador volunteer work with a school in Bury St Edmunds. It's currently I my garden but when it's in a fit enough state it will move to the school grounds and hopefully be the seed of a new Astronomy Club in the area. I've already started doing after-school solar system and rocket making/launching sessions, so hopefully the scope will grow the club into something accessible to many children in the area. The reason for the post is I'd like to discover more about the provenance of the scope, so I wondered if any SGL members would be able to help? The primary mirror is 300mm diameter, the secondary elliptical mirror is 63mm (minor dia) by 90mm (major dia). Estimated focal length 1560mm, so f/5.2-ish. The tube is 1.6metres from the back of the primary box to the front of the tube; the front tube is 390mm diameter. It stands on a massive concrete block, angled at 52 degrees, which takes 4 men to lift... So far I have stripped it down, cleaned the bearings and regreased them so it is useable. I successfully collimated it with a Cheshire - first light showed not much coma, so happy with that for now. The focuser is rather tired and it needs at least a RA drive to make it easy to use, and the primary needs recoating. I believe it originally came from Norwich Uni, but I have no details. If anyone recognises this magnificent instrument or knows anything about it, please let me know - it'd be great to share this with the school as excitement mounts! Current state, in need of a lick of paint Original state (old photo)
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Hey everyone ! I am new to this site , don't know how to properly use it , but hope someone will help me As the topic says , I am trying to buy my first telescope , and am quite excited for it. I have been reading wuite a lot about astronomy , so I know most of the basics , but have many many unanswered questions ... xD I was originally looking for a scope for viewing the planets , but well , after learning more , I thought that maybe a scope that can show only planets will eventually get a BIT boring , and will not be used much (although I still admire the planets and still will want to observe them). Just a quick info on me : I live in a city , have no place to go / or car to transport my scope to a darker place , live in a building , hope to observe from the rooftop. My ONLY CONCERN about this is that from my balcony I can see Vega at night , and as depressing as it may sound , nothing more .It may be because there are buildings covering my view (I at least hope so that's the case) or light pollution , although the place I live is in the orange to red zone in many light pollution maps. So originally I stumbled upon the Orion Starseeker IV 80mm GoTo refractor. http://www.telescope.com/Telescopes/GoTo-Computerized-Telescopes/Orion-StarSeeker-IV-80mm-GoTo-Refractor-Telescope/c/1/sc/15/p/113919.uts Thought it was good for the GoTo and stuff , but after doing some research , got concerned about the sturdyness of the mount.Some said it was too shaky (I have almost constant winds of about 10mph at night here) . Plus after some while I discovered DeepSpace and got even more interested in it than the planets . So I started to seek for reflectors. After a while I discarded Dobsonians as an option , cause I do want to do astrophotography ( just amateur , not gonna spend money on expensive DSLR s or sth) . And maybe in the future I will want to do some more serious astrophotography , so it will be very sad , if I have to change the scope later , if I want to... So after doing some research I am currently watching these scopes . 1. Orion 9827 AstroView 6 Equatorial Reflector Telescope . https://www.amazon.com/dp/B0000XMSR0/ref=psdc_499154_t1_B01N2HJBQC 2. SkyWatcher Explorer-150P EQ3-2 Reflector. https://www.firstlightoptics.com/reflectors/skywatcher-explorer-150p-eq3-2.html The only downside of these is that they're not GoTo (The second one has an option , but it's out of my price range) , but I think an additional RA motor drive will do the thing. At lease if I will be able to find anything in my sky ... That's it ! If you own/have used any of these scopes tell me more about them ! What you like/dont like etc. ANY GENERAL ADVICE IS APPERCIATED . Thanks ! -
Hello guys, I may have found exactly the forum I need here I would be really glad if you could help me a bit please : I love stargazing on the mountain next to home (low light pollution), but now I want to level up. I mean, I'd like to use a device that is better than my eye to see the night sky. The problem is I am quite lost between telescopes, lenses, reflectors, refractors, and hybrids devices etc. So here I am, coming for your advice that will be, I am sure, of great help. Here's my question : what device is best suited for my use ? I'd like to see constellations and close deep sky like big galaxies (andromeda M31 for example). I am aware that refractor lenses are less bright than reflexion telescopes but I'm not certain which one to buy. > The main purpose would be a looking through device, but ideally if I can plug my Canon DSLR it would be fantastic. What are best brands for an amateur ? I prefer to pay more but once than cheap but twice and have a budget of around 250-300 € (if one is a bit above but really effective I can go a higher). Thank you a lot in advance for your time and advice ! Golfox2
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Hello, i got my Cannon 750D few days, and im thinking of buying some adapters so i can connect it to my telescope. Will a T2/1.25 eyepiece projection adapter and a T2/EOS adapter enable me to connect the 2 together? Also im wondering why a piece of plastic and some metal is so expensive :)))). -Ahgi, Clear skies! -
I recently posted about my first successful collimation experience (an SCT). I'm sure we all have our stories, of those moments when we perceived optical clarity. Come on everyone tell us of those collimation 'eureka' moments and your experience of your first observing session immediately following. Paul.
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Hello All! Currently, I have a Meade ETX 90 telescope. I really like it and get great views of the moon and planets out of it. However, I am hoping to upgrade to a large reflector. I am looking at various scopes ranging from the Orion SkyQuest XT8 to the forbiddingly pricey Orion SkyQuest XT12i Intelliscope. I know that aperture is one of the most important things to consider in a telescope, but I also realize that people can get "aperture fever" and go for scopes that are unnecessarily large. I am wondering; Is a bigger aperture worth the price jump from 8'' to 10'' or from 10'' to 12''? How much more will I be able to see? I have heard that the best telescope for a person is dependent on the kinds of things they want to observe. I don't really look at deep sky objects (though I am getting increasingly interested in them), and mostly enjoy the moon, planets, and a few double stars. I want a telescope that will accommodate this, but is also able to have a great grasp on deep sky objects. Honestly I think I am on the right track with the scopes I am looking at, but I really want some advice on which size is best for me. What do you think? Thanks for the advice!
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Hi, I was asked on a Swedish forum to put an "Astronomical Dictionary" on my homepage. I have made a test page in an easy form. Astronomical related words linked to wikipedia. It aims to the beginners in astronomy so it should not be too complicated words. http://astrofriend.eu/astronomy/astronomical-dictionary/astronomical-dictionary.html Let me know if it's useful and and I shall add more words. /Lars
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Hi all after a couple chats with a great artists/teacher mr ken jones a local guy and great advice on sketching I decided to get the sun rise over the Vallis Alps,I used the charcoals and conte pencils as I waited a few hours for the shadows to take the shape they did I was amazed by it yet again the valley being 110km long and around 10km wide I took a few,snaps,to get diferent contrast my chats payed i did not get to finish it as the temperature dropped and the cold got the better of me keep looking up pat
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Hello All, I just picked up my SW 130 reflector today and it looks great. Ofcourse it is raining outside, so I have been looking at a streetight out the living room window and practiing focusing and aligning the finder scope. I am waiting on my Baader zoom but everything looks good so far. Collimation has held from the shop to home. I have it on a vixen porta ll mount. The porta ll seems like a nice piece of kit (as you guys say across the pond ). Thanks to everyone for their help I feel I made an informed decision, that fit my budget and expectations. Mike
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After reading astro baby's review of both scopes it seems to me that the130p would be a much better beginner scope. However she also goes on to say that after a few months she wanted a bigger scope. This is what I am afraid of is using the 130p and then in a few months wishing for something bigger. My sessions will be short at this time, so I guess I am looking for a G&G scope. I really like the 200p and on a Losmandy alt az mount it would be (I think) a great visual scope. The weight and cool down time are the main issues stopping me from buying it. Iam looking forward to your thoughts and tips. Thanks Mike -
Found a old Celestron 21066-wos-a
Revilo posted a topic in Getting Started Equipment Help and Advice
Hi all, was just going through the garage to find something and had come across my dads old Celestron telescope the ,model of the scope says it’s a 21066 wos a. The focal length is 900mm and aperture is 2.3”. Was wondering if any of you knows something about this telescope? I’m guessing it’s not that great. here’s a few pictures of it. Olly. -
After a lot of work collimating my ES PN 210 8" Newtonian (made it in the end!) I got to thinking of replacing the collimation screws with screws with like small handles or wings. Handles on the screws that are bigger than the knurled screws would also provide more precision. ES have ignored me. I could pull one of them out. But I wouldn´t know how to read the threading. Does anyone know the specifics of the collimation screws provided with the ES Newts? Any ES Newt owners out there? Clear skies Bjorn -
No doubt many of you already know about this but I came accross this free ebook and I thought some of you might be interested ... The book has 188 pages and includes around 70 odd black and white images of nebulae and clusters captured in the few years at the end of the 1800s and early 1900s. One example is plate 55, the Trifid Nebula The ebook can be downloaded for free from : http://www.gutenberg.org/ebooks/36470- 6 replies
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Hello Everyone, I am nearing the time when I would be getting my first ever telescope through a friend from UK who'd be visiting Pakistan in a few weeks time. So I have to finalise my decision as to what am I getting during these days. I have been stargazing for some time now. I have done it through my own eyes for a start so far and I must say that it has captivated me already. I was thinking about getting a good binoculars for the sheer excitement of it but then I cannot wait to use a telescope so I have decided to bypass the binoculars and get myself a telescope. I have done my bit of research so far and I kind of know what I want yet I just want to be sure that what I am getting will not disappoint me and therefore need your kind advice in letting my know if what I am about to get for my stargazing would actually fulfil my gtarzagin 'needs' and I call them needs because I do not want to compromise too much on these. So my needs or shall we say requirements are as under: 1. DEEP SKY: I am deeply interested in the deep sky. So you can call me a DSO person. I do not want sharpness of the view for the moon or planets I can compromise on that for as long as I can dive deeply Therefore refractors are out of question for me. 2. TRAVEL: While I would use the telescope mostly on my roof top however which is in the city and so I plan to visit two other locations where I would be taking the telescope along. (a). I plan to go to my father-in-law's apartment at a hill station located at the foothills of the Himalayas called Margalla hills (6000 ft high) twice a year maybe once and (b). to the village of a friend that lies at the base of the Malakand hills which are the foothills of the Hindukush range. One location is just a 40 minutes drive whereas the other is 4 hours away. So portability is there and also durability. These are the two 'needs' I cannot compromise on or would not want to compromise upon. Therefore, what I have in mind is as under: (BUDGET: I cant go beyond 100-120 Pounds maybe 140 Pounds max.) - A Newtonian Reflector within the 114-127 mm aperture range. - I do not have a clear idea of the focal ratio but my research tells me something under 10 is good perhaps near to 5 being great. Is that correct? - I think the telescope should have a parabolic lens ? plus the lenses need to have a coating of some kind for durability ? - An Equitorial mount is best ? if yes, I shall be getting that (I have no interest or budget to go far the motorised ones. The go-to ones. Kills the fun and excitement of locating something yourself through star charts etc. By the way I have downloaded Stellarium on my computer and am getting familiarised with what I behold when I look upwards I saw the Celestron Powerseeker 114 but it had real bad reviews. There is one made by MEADE which is a short tube 127mm and the short tube is good with portability. Similarly there are other options available. Anyway guys, based on the above, what do you recommend? And please no refractor related advice I will be getting a reflector and that is for sure. But which one would suit my needs best is what I am confused about. Kindly enlighten me... Regards, Sidd. -
hi.. I heard someone make 16" reflector with firex glass. my wonder is this could be realize with just one man's hand? i think this would be very precise curve. can hand made would be good? and if yes, how? thanks
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Hello All, Today I am going to the shop to buy either the 150p or 200p. I am interested in visual only and I am going to start with lunar observing . I want something I won't be bored with in three months and something that I can manage weight wise so that I will be able to take it outside with not alot of effort. I am sure you guys have either been in this dilema or know someone who has, I was leaning towards a 130p for a light G&G but I want as much aperture as I can manage. I have read in other posts ,as far as newts go ,that the 200p is the sweet spot in the lineup is this true? Thanks in advance for any help you could offer. Mike
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Hi All, I purchased a GSO 6" f/4 Newtonian "Astrograph" late last year and eventually found that stars on one corner were egg shaped while taking images. I narrowed it down to improper centering of secondary mirror from the factory and resulting tilt. Long story short, after numerous iterations, I used the Advanced Newtonian collimation technique by Astro Shed guy and ended up with the below pic of the optics. Does it look ok or do I need to do more? I will be checking with a Howie this weekend too.
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Greetings stargazers, I'm considering buying a new telescope (my first telescope) for astrophotography, and some visual astronomy. But I can't decide which type should I get. I mainly want to photograph deep sky objects. After testing some variations in Stellarium I am worried that some deep sky objects won't fit into the aperture of an 8" reflector. I'm wondering which type should I get. And also I'm worried that I won't be able to photograph anything with a small refractor because I live near a city. I am also open to any suggestions for a beginner astrophotography telescope. (around 800$ would be perfect) Thank you:) I apologise if I made any writing mistakes. Edit: I'm considering buying a Bresser Messier 203/800 or a William Optics Zenithstar 61 but I'm still open to any suggestions. -
Hi again About 2 years ago i built a 4.5 inch ultralite fold out travel / hiking Dobsonian. weighing in at about 2.5 kilos with eyepieces, collimator and tools. Here is a link to a Thread about the 4.5 Dob - http://stargazerslounge.com/topic/237230-45-compact-travel-scope-for-hiking/?hl=compact This works well but i always felt i could get it lighter and more compact when packet down also me loving building scopes so much i will find any excuse to build another one. This time i have decided to go all metal. Mainly using Aluminium. i want to design the dob as minimal as possible. All i need to do now is design the mount. probably something very simple. here are some plans and some of the build so far. thanks for reading. Pete
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