REVIEW: Celestron Firstscope PART 1 - The Littlest Telescope ( and the easy fix ) Reflactor

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Reflactor

Reflactor

Күн бұрын

This is a review of the Celestron Firstscope, including how to make it better at no extra cost. Is this THE BEST starter telescope for kids? For the price, it just might be...
#celestron #firstscope #telescope
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Пікірлер: 97
@thingsido6303
@thingsido6303 6 ай бұрын
I was 13 years old way back in 1976 and took my dad's Bausch & Lomb 15 to 60 power 60mm Zoom Telescope and tripod and focused it on Saturn. I could see the rings! I still remember the thrill it gave me!
@reflactor
@reflactor 6 ай бұрын
That is a truly wonderful memory - having Saturn burned upon the brain. Thank you for sharing!
@markscungio2996
@markscungio2996 6 ай бұрын
Mayflower branded Japanese 60mmx800mm refractor, 5x24 finder alt-azimuth mount, one threaded slow motion rod adjustment...SR4, H12,H20,Moon filter. Made by Royal Astro...loved it!! Had it from age 12 to age 20...parents sold it at a yard sale while I was in USAF😢
@reflactor
@reflactor 6 ай бұрын
Nice! Pretty much any Japanese made telescope is going to be pretty good quality. Sorry to hear about the unfortunate parental decision while you were away!
@VA3DSO
@VA3DSO 6 ай бұрын
My first telescope was from Sears. It was a tiny 40mm (yes, 40mm!) reflector (yes, REFLECTOR!) on a spindly little wooden tripod. It came with just one plastic eyepiece (likely a Huygens or Ramsden design) and I saw the Moon, Jupiter and Saturn through it. My parents had bought it for me for Christmas in 1979. Best Christmas ever! I now have a telescope that has five times the aperture (an 8 inch SCT) that I love using. But I still have that little Sears scope, and I take it out once in a while to relive those early years of observing. Thanks for the great videos! I have been thinking about getting a Celestron Cometron (similar to the Firstscope you reviewed) and you might have just pushed me over the edge on that. Cheers! 🙂
@reflactor
@reflactor 6 ай бұрын
Wow! A 40mm reflector? The secondary mirror must've been tiny! And I thought this telescope was small! The Cometron is definitely an interesting telescope. In my opinion, it's a perfect Moon scope. Clear skies!
@tyfish7
@tyfish7 6 ай бұрын
My first telescope was a Celestron refactor that I couldn't figure out how to work at the time My second telescope was one of these Firstscopes actually, set me on a love of reflectors ever since. I actually found it the last time I went to my parents house and fixed it up with info from your videos!
@reflactor
@reflactor 6 ай бұрын
More proof that starting with a simpler telescope can generate a stronger interest in the hobby. I'm glad the videos have proven helpful! Thanks for your comment. Clear skies!
@ivangottapseudonym8849
@ivangottapseudonym8849 6 ай бұрын
Thanks for that mask tip with respect to spherical mirrors. Looking forward to trying that. 2nd hand 4.5" Starblast tableto dobsonian. Use it constantly.
@reflactor
@reflactor 6 ай бұрын
Congrats on the Starblast - no need for a mask! Your telescope is wonderful. In fact, it is THE telescope that the Library Telescope Program uses: www.librarytelescope.org/
@Vic-pz5oh
@Vic-pz5oh 6 ай бұрын
Tesco 4vte refractor with a built in zoom eyepiece which you clicked in and out on a tabletop tripod.
@reflactor
@reflactor 6 ай бұрын
Were you happy with it?
@Vic-pz5oh
@Vic-pz5oh 6 ай бұрын
@@reflactor I think it's still in dad's roofspace.i remember it came with a rand McNally moon map.i thought it was brilliant at the time in the late 70s
@10intexas
@10intexas 6 ай бұрын
My first scope was a Tasco Starguide 4 that I bought for $100 on craigslist.. This scope was the predecessor to the SE series from Celestron (after they split from Tasco) and is virtually identical to the 4SE. It has the GOTO AZ mount but with a built in equatorial wedge. You can see Saturn's rings clearly and Jupiter's cloud rings with a really good 10mm plossel. I now have a C9.25 (aperture envy) on an AVX mount but I still use the 4" Starguide when I don't want to schlep the big scope and mount.
@reflactor
@reflactor 6 ай бұрын
It sounds like you've had some pretty good telescopes as your first ones - glad to hear it. That'll keep interests longer. Thank you for watching and clear skies!
@cliveroberts415
@cliveroberts415 6 ай бұрын
My first scope was a little 2 inch refractor on a wobbly table top tripod, my parents bought it for me as a Christmas present way back in the sixties. I saw the craters on the moon, Saturn's rings, Jupiter's moons and the phases of Venus amongst other things. I have much more advanced scopes now but nothing has ever matched the thrill of using that little scope.
@reflactor
@reflactor 6 ай бұрын
It's hard to beat the memories of those first astronomical discoveries, even if the telescope was inferior to modern day options. Clear skies!
@morenomarzolla
@morenomarzolla 6 ай бұрын
Excellent review, as usual! I have this exact same telescope, and can confirm everything you said. I really like the mount, which is smooth and solid. As you and other commenters have said, the optical quality is not very good due to the spherical mirror; this is to be expected for this prince point. You definitely need a set of better eyepieces (I happen to own the "much better set of wide angle eyepieces" mentioned in the description and recommend them). Although I bought this telescope out of curiosity since it was cheap, I have found a couple of uses for it. First, it is an excellent scope for outreach: I sometimes bring it with me at the open nights at my astronomy club and visitors love it, especially children. Second, when I am too tired to setup my big scope but not too tired to go to bed, I grab this scope, go outside and start looking up. It is not good for the planets, but it is adequate for large, bright deep-sky objects like the Pleiades, the double cluster in Perseus, the Andromeda galaxy, the Orion Nebula, the Christmas Tree Cluster, the beehive cluster... In conclusion, it fits my needs and was cheap, so I am quite happy with it.
@reflactor
@reflactor 6 ай бұрын
Thanks! As you mention, better eyepieces make a big difference (and the masks make a huge difference). If I were a child and had to choose between one of these and binoculars, I would go for one of these little Dobs.
@artyombeilis9075
@artyombeilis9075 6 ай бұрын
I wonder if it is possible to mask Central part of the mirror and use only external ring - this way you can get more light. i.e. stick a circle over the 2ndary mirror holder and mask internal rather than external part of the spherical mirror.
@reflactor
@reflactor 6 ай бұрын
That's a good question, and definitely worth a test. I think the main idea is that the central portion of a spherical mirror more closely resembles the parabola than the outer portions. In other words, most of the spherical aberration effects come from the outer portion of the spherical mirror. I could be wrong. A test is in order!
@wojciechbanasik8422
@wojciechbanasik8422 6 ай бұрын
Skywatcher 90/900 on eq3 was my first. Got it in April this year. Since then got second hand skywatcher 150pds (still using it on my eq3 mount) and saving money for a 10inch dob. Dipping my toes in astrophotography with my refractor but CA is quite obvious unless shooting mono. Few weeks back had a good night so pushed and managed 25 panel mosaic of the 80% moon. Quite pleased with it. Cheers for another great video! Content like yours really really really helps us beginners. Keep doing what you're doing and we'll keep loving it! Clear skies!
@reflactor
@reflactor 6 ай бұрын
Congrats on the Moon capture. I am a crazy fan of Dobsonians - they rock. At a minimum, get an 8 inch (for max portability). The bigger ones are great, but not as portable. I'm glad you find the videos helpful (I've got a lot planned).
@dryisi
@dryisi 6 ай бұрын
My first telescope was and still is an 8 Inch dob. I have upgraded it with the Celestron star sense which has greatly improved my viewing experience as a beginner stargazer.
@reflactor
@reflactor 6 ай бұрын
If I'd started with an 8 inch Dob, it would probably still be my only telescope. It is the one that I heartily recommend to anybody who asks (who has the budget). Very tough to beat! Clear skies!
@janomacko5764
@janomacko5764 6 ай бұрын
In the early 2000's my parents got me an overpriced Tasco Galaxsee with the dreaded Bird Jones design and hopelessly out of collimation. I was actually using the masking technique shown in this video to improve the optical performance, and I was able to see the main cloud belts on Jupiter.
@reflactor
@reflactor 6 ай бұрын
Thank you for the comment! Yes, the dreaded Bird Jones telescope! I'm working on a pretty sizable two-video series on the Bird-Jones telescopes. Last night I was testing the masking method on Jupiter and discovered what you already discovered, I could see the belts. Very surprising from such a tiny telescope. Clear skies!
@gregoryrandle4929
@gregoryrandle4929 6 ай бұрын
My first scope skywatcher heritage 150p stray light no problem make or by a shroud very portable and great optics
@reflactor
@reflactor 6 ай бұрын
It sounds like you were very happy with your first telescope - that's awesome!
@engineerncook6138
@engineerncook6138 6 ай бұрын
I as 10, about 1963, 3" Gilbert 80x Newtonian on a very cheesy tripod and a tiny ballhead. Cardboard tube, no finder. Without a finder, it was very difficult to find any objects. Turned me of of amateur astronomy for 55 years. Tried to build a 4" newt a few years later but never finished it.
@reflactor
@reflactor 6 ай бұрын
The good news is that you are attempting to come back to the hobby. The cheap JC Penny telescope I had from the 1980's turned me off of astronomy for over a decade. Then I built a 6" Dobsonian from the Richard Berry book in the mid 1990's and I've been hooked ever since.
@conchobar
@conchobar 6 ай бұрын
Saw an inexpensive 6" mirror and secondary on ebay for $50 and started my path (2006-is). Another $250 later 😅and I ended up with a rather janky 6" dobsonian, that was worse than any $300 unit from off the shelf. Most of the fun was building it, and it still impressed family members looking at Jupiter and its moons.
@reflactor
@reflactor 6 ай бұрын
So you built your first telescope? Cool! After my JCPenny telescope disappointment, I got out of the hobby for ten years before building my first Dobsonian in the 1990's. Clear skies!
@hedgehog3180
@hedgehog3180 2 ай бұрын
Parabolas are actually mathematically defined from this property that all reflections off of them focus in the center point.
@pepeimc
@pepeimc 6 ай бұрын
Great video as usual. I got my first telescope relatively recently, 4-5 years ago and it was actually for my son, who lost interest quite fast. It was a skywatcher heritage 130p, optically very good, but stray light was a nightmare, then I bought a heritage 100p, solid tube, and found it much more enjoyable despite being smaller. In deed it would be nice if you can try and review ir (or the Orion skyscanner). I still own it (2 of them) and I don’t think I ever will be getting rid of it, I really love this little telescope. Talking about 76mm mirror, I bought a second h a second ham 76mm parabolic mirror (from a skywatcher infinity 76) to make a travel scope, and it is incredibly sharp. Greetings!!
@reflactor
@reflactor 6 ай бұрын
It's rare to find a telescope that you enjoy so much that you wouldn't think of selling it - that's how I am with my 8 inch Dobsonian. With regard to reviewing telescopes, my path is pretty random. It's whatever I find at yard sales, estate sales, Facebook Marketplace, or when friends and family bring broken ones to me. Clear skies!
@EvenTheDogAgrees
@EvenTheDogAgrees 6 ай бұрын
Lol, I always wondered if you were a Dutchman who moved to the States a long time ago, as I seem to hear a hint of a Dutch accent in your speech. But having heard you pronounce "Huygens", I think I can safely put that theory to rest now. 😂 Anyway, first telescope. Was not so long ago, actually. Less than a decade ago for sure. I was well in my 30's, perhaps even early 40's at the time. I believe my interest was peeked by stumbling over some astrophotography videos here on YT, probably Nebula Photos and Astro Backyard. I told a colleague from our Romanian office I was considering getting a telescope. He moved to Belgium, and while looking for a place to rent, stayed at my place for a couple of weeks. Short time later, there's suddenly this large box waiting for me at the office. Turns out the guy bought me the Omegon 130/920 Newtonian on an equatorial mount. After some experimentation, I sadly had to conclude it was not suitable for astrophotography, even with a lightweight mirrorless camera. But it's great for visual observation and looking at the planets. I've since bought a smaller refractor astrograph and a star tracker, but due to circumstances (still recovering from a medical condition, my energy levels are pretty low ATM), I haven't been able to do much more than kick the tyres on that setup.
@reflactor
@reflactor 6 ай бұрын
Well.... I'm descended from German & Irish relatives (among others), but my accent is a standard "midwestern" accent from the Ohio area of the USA. I'll have to practice the proper way to say Huygens in Dutch. :) Nebula Photos and Astro Backyard are awesome - way beyond my skill levels (also try Astrobiscuit). Hopefully you bounce back pretty quick from the medical issue and get to using the cool telescopes you have at your disposal. Clear skies!
@EvenTheDogAgrees
@EvenTheDogAgrees 6 ай бұрын
@@reflactor Interesting. I knew the US had many regional accents, but never stumbled across this one. To me it sounds like someone from the Netherlands who's lost most of his accent after decades of living in the States. And yes, I know Astrobiscuit. Bit of a mixed bag for me. For my taste, he's a bit too careless with the equipment funded by his patrons, and a bit too aggressive in pushing his viewership towards paid membership. Other than that, his content is rather decent indeed. His videos are usually highly entertaining, and a big part of that is his storytelling. He's good at creating a narrative that keeps you watching for more. Between you and me: I'm mainly watching for the bunny. He's the _real_ star of the show. 😂 Another one I'm enjoying lately is Alyn Wallace. If you haven't heard of him yet, perhaps worth checking out.
@AmatureAstronomer
@AmatureAstronomer 6 ай бұрын
Aperture reduction also reducers chromatic aberration in achromats.
@reflactor
@reflactor 6 ай бұрын
Thank you for that information! I did notice that the slight blue tinge around the moon also disappeared. Sounds like aperture masks have many advantages. Clear skies!
@Mighty3Eagle
@Mighty3Eagle 6 ай бұрын
My first telescope was a Meade 4500 reflector on a gem. I was hooked, so I soon upgraded to a Meade 10 lxd55 Schmidt Newtonian. Wish I still had them.
@reflactor
@reflactor 6 ай бұрын
It sounds like you have experienced some very good telescopes!
@mindyindyindy4811
@mindyindyindy4811 6 ай бұрын
This past August, I was organizing a watch party for the meteor shower for some friends. Word got out and I was suddenly expecting a much larger crowd than I originally planned for. I figured this would be a good excuse to buy a telescope so we could look at some other stuff as well. After a week of frantic research, I found a used Starblast on an EQ. I used your two videos to start things off and I've been hooked ever since.
@reflactor
@reflactor 6 ай бұрын
Congrats! I really like the Starblast telescopes (I'm partial to the Dobsonian version). I'm glad the videos were helpful. Clear skies!
@ricardohdz1987
@ricardohdz1987 6 ай бұрын
Nice video, mine was one of the cheap nat geo telescopes that had a really bad finder and it was almost impossible to use, i had second thoughts about telescopes after i got it but i was so interested about space that i never gave up and eventually got a better telescope
@reflactor
@reflactor 6 ай бұрын
Congratulations on the perseverance - it sounds like it paid off. Clear skies!
@johngiromini5745
@johngiromini5745 6 ай бұрын
Now that is a great informative video, John. I especially like the sound effects of the scissors.
@reflactor
@reflactor 6 ай бұрын
Haha, thanks. I actually had to reduce the sound of the saw by about 50% - it was overpowering! I was pretty shocked at how effective that cardboard mask was. I've since found that there is a 3D printable version on Thingiverse. Thanks for watching!
@jackieblank4249
@jackieblank4249 6 ай бұрын
J.D. Love ur little scope. You Betts get looking tonite it's pretty clear down here in the Bayou State. I'm too tired n too cold to go set up. Might try. tomorrow.
@reflactor
@reflactor 6 ай бұрын
Winter is coming for sure. I'm not a fan of the cold weather.
@jackieblank4249
@jackieblank4249 6 ай бұрын
I looked at Jupiter a lil bit. Then the clouds rolled in from the Gulf of Mexico.
@JollyFigNut
@JollyFigNut 6 ай бұрын
I haven't used on of these small beginner dobs but people give them high praise, might pick one up just to mess around with. As for my first telescope it was the Celestron Travelscope 90mm refractor, got it last Christmas and I have to say it's not a bad OTA for $90... the mount on the other hand was garbage but considering the purpose it does work for lower magnifications. I found the viewfinder scope not so great with bad eye-relief but taking the lens elements out resulted in an adjustable tube to look through similar to your straw method. The actual OTA was genuinely good, no astigmatism and it's sharp to about 70% from center, the defocused star test was fairly round too. Being an achromat it does suffer from chromatic aberrations but that's to be expected for the cost. Overall I really enjoyed using it, though haven't used it as much since I've upgraded to a new Orion XT6 (with a 2" metal Crayford focuser) and have been loving it. To conclude, I would not recommend any cheap refractor with a tripod, I knew the mount would be bad going in so I didn't mind it too much but to the average beginner it can put a sour taste into their first experience. Before my first telescope I started astronomy with a cheap pair of binoculars and I still use them occasionally for astronomy, if you want to get into astronomy cheaply then get a pair of 7x50 binoculars you will not regret it.
@reflactor
@reflactor 6 ай бұрын
I've used some telescopes where the OTA wasn't bad, but the mount was awful and ruined the experience. You may want to consider a red-dot finder they are only about $20 these days. Congrats on the XT6 - Orion Dobs are wonderful.
@JollyFigNut
@JollyFigNut 6 ай бұрын
@@reflactor Got a Rigel quick-finder for it not long ago. The red-dot that came with the XT6 had awful parallax and could never hold at infinity so it was trashed pretty quickly, it was the only issue I had with the XT6.
@reflactor
@reflactor 6 ай бұрын
I bought a Rigel earlier this year and it came with the knobs smashed against the opening of the black case. I called to get a replacement and asked the guy to check it before he sent me a replacement. They all had the problem. Their quality control seems pretty poor. Telrads are unnecessarily bulky, but their quality seems pretty good.
@shinyparts
@shinyparts 6 ай бұрын
The Skywatcher Heritage 76 comes with the finder and a few other parts for the same price as the Celestron, same scope but found the Skywatcher to be sightly better built.
@reflactor
@reflactor 6 ай бұрын
This is good to know!
@RickMcQuay
@RickMcQuay 6 ай бұрын
I got a Cometron dirt cheap because the metal rod that runs through the focuser was bent. I hammered it straight and tuned it up, collimated as best I could, and it's a fun little moon scope. Blinding, I can't look at the moon without a filter or sunglasses. Mine came with a cheap finder scope, 20mm and 10mm eyepieces. I would probably recommend good binoculars instead.
@reflactor
@reflactor 6 ай бұрын
A telescope becomes a little more meaningful when you do repair work on it. I also like suggesting binoculars too. I think with the target audience, kids, they would probably choose the cool looking telescope. Whatever keeps their interest.
@BennyKleykens
@BennyKleykens 6 ай бұрын
Cute :-) My first experience was with a 12" Dobsonian that I rented from an Observatorium because my neigbor believed the Earth was flat and the Moon a 2-D projection. I did not manage to cure him but did end up with a sweet Hobby 😂
@reflactor
@reflactor 6 ай бұрын
Sorry to hear that you couldn't convince your friend, but happy to hear that you've got a thriving astronomy hobby! Clear skies!
@littlesunny63
@littlesunny63 6 ай бұрын
I was gonna use one for a finder scope on my 16” dob. BTW, the unobstructed aperture mask can be applied to any dob and actually tones down the excess brightness on targets like the moon and brighter planets. Just cut your hole 40% of the total aperture.
@reflactor
@reflactor 6 ай бұрын
This is really good to know. I've created a few of the off-axis masks for my Dobs, but I usually just do a trial and error on hole size - usually too small, but I want to avoid the secondary struts.
@notmyname327
@notmyname327 6 ай бұрын
Really interesting scope! It seems like it's only really useful for the moon, right? But like you said, it's good enough for kids to get started in astronomy. I still don't own any telescope, but I'm building two: a 114 mm aperture 900 mm focal length with cheap Aliexpress mirrors, and a 150 mm aperture 1200 mm focal length I'm grinding myself. Both of them have spherical optics, but I trust the focal length is enough to keep aberrations to a minimum.
@reflactor
@reflactor 6 ай бұрын
I think it works best on the Moon, but... I used it to get a good view of the Orion Nebula and Jupiter (with the mask). Man, oh man, do I love to hear that you are BUILDING a telescope! I built my second one (6" Dobsonian) from the Richard Berry plans in his book "Build Your Own Telescope". Thanks for sharing!
@JoeJaguar
@JoeJaguar 6 ай бұрын
hey John ya its not the best scope BUT when gift giving for the xmas season noone gonna give a $1,000 scope. So if this makes new people like the few things that they like and they get into the hobby sure why not.
@reflactor
@reflactor 6 ай бұрын
Exactly. It's simple enough that the user can skip any complex setup (ala equatorial mount) and get to the good stuff. Then buy a nicer one.
@JoeJaguar
@JoeJaguar 6 ай бұрын
YES AGREE thx for video@@reflactor
@landtechnik4k
@landtechnik4k 6 ай бұрын
i wonder what would be Possible if there would be a super high quality Version of it
@reflactor
@reflactor 6 ай бұрын
That's a very good question. I'd like to see what it would look like if somebody took the time to make a parabolic 3" mirror. My guess is that the basic options for a parabolic 4.5 inch parabolic setup isn't much more than a 3 inch setup, so there may be some financial limitations on the business side.
@Stevie75
@Stevie75 6 ай бұрын
I had a chance of buying one new (old stock) for 30 something euros years ago. The sight of it with a pentax eyepiece in it is just silly. 😅
@reflactor
@reflactor 6 ай бұрын
I know, right? At one point I had a Tele Vue Radian in it, quadrupling the overall value.
@manoharbelur1436
@manoharbelur1436 3 ай бұрын
How to convert camera tripod to attach telescope? quick release is very wobbly
@reflactor
@reflactor 3 ай бұрын
A lot of telescopes have a 1/4-20 hole on the bottom to mount to a camera tripod. Thse Firstscope's don't unfortunately.
@billducas
@billducas 6 ай бұрын
Where did you find the info on how far to stop down the optics?
@reflactor
@reflactor 6 ай бұрын
It was a combination of things. There's a Thingiverse set that maxes out at F7 (at 300mm, that puts the mask diameter at about 1.75 inches.). There's also a list that floats around the forums (especially on Cloudy Nights) that looks like this: APERTURE TEXEREAU MINIMUM F/RATIO 3 inch f/6.4 4 inch f/7.1 6 inch f/8.1 8 inch f/8.9 10 inch f/9.6 12 inch f/10.2 For a 3 inch, that puts the ideal focal length at 486mm. We only have 300mm, so if you scale it down, you get about 1.8 inches. In the end, I settled on 1.75 possibly because I have a hole saw of that diameter.
@yassinadam-zg7qx
@yassinadam-zg7qx 6 ай бұрын
Hey I love your videos keep up the good work!😀 I have one question. How big should my mask be for a 5 inch telescope spherical mirror. I currently have the celestron powerseeker 127 eq and want to minimize the spherical aberration. I see you made the mask half the diameter of the primary mirror should I do that for my 5 inch?
@reflactor
@reflactor 6 ай бұрын
That's an excellent question! I've been researching this. I saw that the general rule of thumb is to make the hole a given size so that your focal ration is about F9, but there is a table of more specific values: APERTURE TEXEREAU MINIMUM F/RATIO 3 inch f/6.4 4 inch f/7.1 6 inch f/8.1 8 inch f/8.9 10 inch f/9.6 12 inch f/10.2 For your 5" mirror, you'd want to size the hole so that the formula (Focal length/diameter) is about f7.5. The Celestron 127EQ's focal length is 1000m, so you'd want your mask hole diameter to be about 1000/7.5 or 133mm. The mirror itself is only 127mm, so that's not much help. If you go with the f9 suggestion, the mask diameter should be about 110mm.
@yassinadam-zg7qx
@yassinadam-zg7qx 6 ай бұрын
Thanks for the help I will make the mask now and try it out as soon as there are clear skies, sadly I live in florida.😆@@reflactor
@nihar1987
@nihar1987 3 ай бұрын
@Reflactor Great content as usual, you earned my sub long ago, but please stop calling a finderscope a "viewfinder "in almost every video !
@reflactor
@reflactor 3 ай бұрын
Admittedly, I do use them interchangably - that is my mistake. I will try to do better, but... I can't promise. :)
@manoharbelur1436
@manoharbelur1436 3 ай бұрын
Is a 76mm Newtownian worth building?
@reflactor
@reflactor 3 ай бұрын
I would not build a 76mm telescope from scratch. It would be way more expensive than buying one of these.
@BennyKleykens
@BennyKleykens 6 ай бұрын
Spherical mirrors are only okay-ish with a long focal length. Unfortunately there's no market for 2.5" parabolic mirrors. That would probably be a better way to go but who would buy a 2.5" (parabolic) telescope if a 3" (spherical) telescope can be had for the same price. Sad, really.
@reflactor
@reflactor 6 ай бұрын
I think you hit the nail on the head. The demand for small parabolic mirrors just isn't there, so manufacturers have little to no incentive.
@artyombeilis9075
@artyombeilis9075 6 ай бұрын
Anyway I think in the low price range refactors can actually be better. I have svbony 60/400 scope that you can get for ~$60 on sales - and actually it is pretty good scope - you can add 10 and 23mm aspherics for $13 each and 90 deg diagonal for yet another $10-$15 and you'll get very good scope optically with very small CA. (Similar to one you reviewed than) I also added small workaround for horrible mount and it becomes very lightweight travel scope (1.5kg): kzbin.info/www/bejne/aYnceJiOmtGfZpY
@reflactor
@reflactor 6 ай бұрын
Excellent point and nice workaround. Anything to make a first-time astronomers life easier is worth the effort.
@artyombeilis9075
@artyombeilis9075 6 ай бұрын
@@reflactor Ohh I wouldn't recommend it to first time astronomer unless the poor soul already got one. Just way too many issues to handle. Me as experienced user who isn't afraid if tinkering and actually understands the limitations it is different. I mean I can accept wobbly mount if it saves me 1/2 of weight and allows me to take the scope in a baggage without hassle.
@stevejohnson174
@stevejohnson174 4 ай бұрын
Yeah, but the mask makes it about a three-quarters of an inch telescope with respect to light gathering ability, given the central obstruction of about an inch. (area of aperature = Pi x 1.75 = @5.5sq/inch. - [Area of obstruction = 1"xpi = 3.14sq/inch] / 3.14 = 2.35 sq inch. That's not a trick. that's a very steep compromise. The moon is pretty much your only valid target. A better alternative would be to use a Barlow, which effectively multiplies the focal ratio, reducing the spherical degradation. I find it unfortunate that the add-on doesn't include one and I think its composition is completely wrong! I'm assuming for the same price they could have provided a red-dot finder, a 15mm Kelner (or Plossl), and a 2x Barlow, giving it an effective f-ratio of eight, which should be enough to suppress most spherical aberration).
@reflactor
@reflactor 4 ай бұрын
Using the mask also helped with Jupiter, but I didn't have much usable footage to compare. I was a little surprised they didn't have a red-dot finder. I recently bought one of these used for $20 and donated it to the local scout troop. It's a good beginner scope for that kind of thing.
@celestromel
@celestromel 6 ай бұрын
Who is going to explain to the kids why the image is upside down?
@reflactor
@reflactor 6 ай бұрын
That will hopefully cause a very good discussion with their parent or guardian. :)
@DavidMFChapman
@DavidMFChapman 6 ай бұрын
I hate these telescopes! Their 76mm f/4 spherical mirrors are awful. Also, I have seen more than one with the secondary mirror mounted askew. I can’t recommend them at any price. The model you have is the Robert Reeves signature model. He just published a lovely book of lunar photos “Exploring the Moon.”
@reflactor
@reflactor 6 ай бұрын
I spent tonight taking it apart and trying to do a complete collimation on it. Quite tricky given that the primary mirror is glued in place with very little adjustment. It helped a bit, but that cardboard mask made such a huge improvement. I was using it to look at Jupiter tonight.
@alexbuster2177
@alexbuster2177 6 ай бұрын
@@reflactor я не понимаю зачем делают такие телескопы , такое оборудование может убить интерес к астрономии .Диафрагма не решение проблемы , с учётом центрального экранирования от зеркала ничего не остаётся .Лучше для начала купить подержанный рефрактор 3-4 дюйма . Мой первый телескоп был взятый в школе 80мм рефрактор , потом 60 мм но очень резкий рефрактор , первый же купленный мной телескоп новый celestron C6N куплен более 15 лет назад , это был огромный шаг после 80 мм рефрактора .
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