5" Refractor Shootout
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- čas přidán 17. 07. 2024
- Testing the Explore Scientific AR127, the Svbony SV550 122mm F7, and Sky-Watcher Esprit 120 ED for astrophotography in this 5" refractor shootout! Order Rainbow Black here: amzn.to/3TMrjjs
Products reviewed:
Explore Scientific AR127 - bit.ly/4coVTaa
Svbony SV550 122mm F7 APO - bit.ly/3TkiRGI ($60 off if your total is $500 or more with code Nico60 from official Svbony site), other places: linktr.ee/SvbonySV550122mm
Sky-Watcher Esprit 120ED - www.skywatcherusa.com/product...
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❤️ Patreon ❤️
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If you like what you see on this channel, consider joining my Patreon. It starts at just $1/month: / nebulaphotos
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Contents
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0:00 Why am I testing these three telescopes?
4:25 ES AR127 - Physical Characteristics
7:34 Svbony 122 - Physical Characteristics
11:28 Sky-watcher Esprit 120 - Physical Characteristics
17:21 Rainbow Black (sponsored segment)
18:43 Imaging Tests
31:41 Credits (Patreon)
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Video Disclosures
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The Explore Scientific AR127 was bought at retail with proceeds from Patreon.
The Svbony SV550 122mm F7 was lent to me by Svbony for review.
The Sky-Watcher Esprit 120 ED was lent to me by Sky-Watcher USA for review.
The ZWO ASI6200MM and MC are were lent to me by ZWO for use on this channel.
This video is sponsored by Rainbow Black, a novel by Maggie Thrash.
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Channel Disclosures
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I am a member of the High Point Scientific, Agena Astro, eBay, ZWO, Svbony, All-Star Telescopes, B&H Photo Video, Astrobin, and Amazon affiliate programs. Product links in my video descriptions are typically affiliate links, which means, at no extra cost to you, I will make a commission if you click them and purchase something. I also have working relationships with the following companies/brands to receive products to test: Sigma America, Askar, ZWO, DwarfLab, OG Star Tech, Svbony, High Point Scientific, Agena Astro, QHYCCD, WOBoyz, SmallRig, Venus Optics, Astrogear.net, Night Sky Camera, Woodland Hills Camera & Telescope, Hunt's Photo & Video. Any gear received for review and/or brand deals will be fully disclosed in the video. If you have any questions about any of this, please get in touch.
As always excellent and informed, well spoken, and explains astronomy in a way that is easy to understand without being a professional astrophotographer, thank you!
As always, great review Nico! Thank you!
Really enjoyed the video, love how you took this opportunity to help with some of the astro myth busting (or validation!) wrt apo and mono.
The svbony isn’t bad at all, for the price that’s pretty good performance
Chromatic aberrations shouldn’t be a problem at all with the Svbony ED triplet since nobody would use no way near that extrem level of saturation.
i love your content. it got me in to astrophotography
Excellent test!
Excellent comparison. A comparison on the planets and the Moon would also be very interesting.
Absolute love that your sponsor is a physical media that requires undivided visual concentration. The irony is strong; a formerly visual only hobby that is now focused on digital capture, manipulation, and processing of photons, using electrons that can't be used after being disconnected from an electrical grid. Galileo and Gutenberg applaud the irony. PS... I still own and read F Scott Fitzgerald and leCarre while my own rig is churning away capturing photons in the night. I think I might buy this book just because of the effrontery of sponsoring this video.
A very nice comparison Nico, thanks! When I was shopping around, I found the Orion EON 130ED APO (fk61 glass) to be the best value trade-off in this class. In the last 3 years I've really enjoyed using this fantastic visual and AP scope. Performance and build quality were far better than I expected, and you do get the full 5" (plus a bit), so I think Orion deserve a shout. That ES is amazing though in mono. It really makes you think! The reduced contrast is of course due to the spreading of that out of focus light (being just a doublet) rather than anything to do with coatings. You can't get that data back, but the cosmetics can be managed in processing.
I agree,I have an Orion Eon 115mm, best of all I got it for $400 with a vintage orion 35mm ultrascopic eyepiece! Great scope!
Most interesting was the narrow band filter result with the inexpensive scope. Useful for people on a tighter budget to know you can still get great results.
Good review Nico, however, I do wish you were able to include the Askar 120 apo also
The book is great! as is your video!
6:00 Yes that's what it's for:) I'm using an HEQ5 Mount and all my dovetails are scratched pretty bad and have dents from the screws except for my Explore Scientific scope. Great Vid as always
I see the lens cap with calibration hole I made for this scope is still with it. :)
Really enjoyed this video as I have all your comparison videos, answered some discussion questions we have had in the astronomy club I belong to, (Middle Georgia Astronomical Society).
Hermosos teléscopios amigo nico muy buenos para la astrofotografia saludos desde Honduras
Another great video, Nico. Thank you. Are you going to the Cherry Springs Star Party in June?
So the ES AR127 was used at F6.5 , the Svbony 122mm at F5.6 and the Skywatcher Esprit 120mm at F7 ? Doesn’t the F-ratio play an important role in the intensity of the chromatic aberrations? Wasn’t the Svbony disadvantaged because of the lower F5.6 ratio and the Skywatcher Esprit advantaged because of the higher F7 ratio?
A lesser quality reducer can make a mess, but the real reason I'd say is the FPL51 glass used
@@Neanderthal75Still the F-ratio difference between the Svbony at F5.6 and Skywatcher Esprit at F7 is big. At F7 the chromatic aberrations are corrected a lot more than at F5.6. The Svbony 122 triplet is an F7 just like the Esprit so I don't understand why they were not tested in equal terms both at F7.
The only matched flattener available for the Svbony is the flattener/reducer. So yes I could have used no flattener on the Esprit or the Svbony but I don’t like tests that don’t feel ‘real world’ to me even if they make them technically more matched when it comes to specs. What I mean by that is I would never suggest someone use a doublet/triplet for imaging without the matched flattener if one is available. It makes a huge difference to image quality. There will always be minor differences between telescopes, but for me using the included flatteners makes more sense than not using them. (The explore scientific has no matched flattener available).
Yes, and from my testing a matched flattener/reducer can also improve chromatic aberrations. It really depends on the quality of the flattener/reducer and how it is interacting with the telescope optics. All these comments just asserting that reducers universally disadvantage a telescope in tests are off-base IMO based on doing lots of testing over the past few years.
The difference in correction between FPL51 and FPL53 glass is MANY TIMES LESS than the difference seen between the two scopes due to the additive effects of disparate F ratios, optical design, quality of the non ED glass coatings, factory build quality (component variability, build quality, optical alignment) and the field flattener optics quality and match.
With two disparate telescopes like these you can only evaluate the net result.
That's not a bad thing necessarily. The net result is what actually matters. I suggest snobbery over specs is inversely related to the skills of the user anyway 😂
I think you fail to mention in this video the Sky-watcher is listed as Super APO. Isn't that the marketing term they attach to using 2 ED elements in the triplet instead of one? That "should" provide some additional CA advantage.
As to the longer f ratio having an inherently better CA spec. That's actually not the entire picture
The longer f ratio means less CA all other things being equal; but they never are. In reality it just means easier to correct. 😊
The only way to really try to field test the difference between FPL51 and FPL53 is to get two scopes from the same maker and same design where they've upgraded from FPL51 to FPL53.
ES did something like that on their 127mm APOs from FC100 to FPL (I don't recall if it was to 51 or 53).
Franky, I'm not sure that it's worth the effort unless your luck with a distributor or astro club makes it easy. Be prepared though to do pixel peeping and check off axis sources as well as on axis objects.
IDK about flattener for the ES. I have a 1.x for my ED127CF but I think the one I have is discontinued. I believe there are options but VERY expensive.
The other choice is to take new subs focused on off axis bright star. Is it worth it to test the glass?
IDK. Look at the actual Hoya glass specs.
No one can trust the marketing departments of these or others in this world! But results & value is the most important part I feel! Nico the reason to to not markup the Vixen dovetail rail, but like you said makes it harder to fit on some mounts with that as the locking screws are somewhat pointed and mark the side up.
Hi Nico. I actually own a SV550 122 and I have ~20hrs of data with it and my results are just like yours. It indeed has a bit of color fringing but the correction is good enough to justify its price.
Thanks for the review
A UV-IR cut filter should fix most of the remaining fringing too
@@M0unta1n777 the usage of uv/ir cut on refrctors is a requirement so yes I've tried uv/ir cut. The dispersion occurs with wavelenghts longer than 400nm and possibly shorter than 700. So the solution seems to be the Antlia Triband RGB which cuts at between ~425 to ~670. I've tested with the horsehead and seems to do the job os killing the CA
@@RaffaelMarx Yep what I mean is Nico tested these scopes without any filtration and max saturation was applied so it's pretty much a worst case scenario, and the scope still held up pretty well.
It'd be interesting to see how well the achromat could hold up with RGB mono imaging. The broader bandpass of RGB filters would make the difference in focal planes for the shortest and longest wavelengths of each filter on the achromat stand out more, but how much. The difference in wavelengths between the long end and short end of each color filter is a lot less than you got shooting with the color camera, just how acceptable it is has me wondering.
Anyway, thanks for another excellent review video, Nico.
Pity you couldn't get your hands on an Askar 120 for the review
The APO series? Probably pretty similar to the 103APO he reviewed, but would definitely be nice to see
Can’t wait for that PS518 review/first look 😉
Great video, great subject. Does the Sky Watcher have slightly pinched optics? Seen best on pixel peeping hyper saturation.
very well put together comparison, thank you. also i’ve got a question for you, i’ll be shooting the eclipse and i also have the sigma 40mm f/1.4 that i’ll be using to try to get the comet in the same frame just like you! im wondering how you’ll be framing it, will you try to get venus in the very corner and jupiter in the other, with the comet and sun in between? or will you forego venus and get the sun, comet, jupiter, and the pleiades in the frame? im not sure which i’ll go for, im curious what your plan is
Hi Nico, nice video and talk as always, i like your videos.
Well, what i can say, i started with achromatic scope [ST80] and was using a DSLR lens also with it until i managed to buy better quality scopes but not expensive ones, first with 90mm triplet that has FPL-55 which is very similar close to FPL-53, i bought it twice so i have two, then by last year i added 106mm triplet that has FCD-100, i want you to test those optics if you can with same or similar aperture, so one with FPL-53 and one with FPL-55 and one with FCD-100 to see which one is really a better optic after all, i even bought two ED doublets [60mm f/6] with one stated to have FPL-53 while the other just unknown ED which i believe could be also FPL-53 or FCD-100 but they didn't mentioned, i didn't test them but i swear that they both are the same in everything regardless of different brands, the design are just typical, so i also wanted to see how the ED doublet can compare to achromatic and triplet here, and if it is possible can you do like a final result where you combine a data from achromatic with NB and triplet with RGB to see if it works good enough, or for example Ha from achromatic and OIII from triplet and see.
Thank you very much for all your efforts and videos Nico, i always like to follow your videos.
Awesome review as usual! Will it be possible if you could review different entry level sensors in astro cameras like the IMX 533, IMX 585 etc. I was looking at the new ZWO ASI 585 MC Pro and was wonding how that will stack up to the established 533 MC Pro.
Interesting results. With the vignetting, the skywatcher has the advantage because it's shooting at it's full focal length . With the reduder it would be very similar i guess. I would like to see the difference between a fpl-53/Lanthanum doublet compared to the triplets?
Thank you. I was always saying that the Svbony 122 triplet is "a poor man's Esprit 120".
And this test proves the theory that when shooting with narrow band filters and a monochrome sensor, an ED doublet is 'good enough' (and you can spend your savings on the optical tube on NB filters and mono sensor)
Don't forget that the Svbony 122 triplet was disadvantaged being tested with the reducer at F5.6 and the Esprit 120 at F7. The Svbony 122 triplet at its native F7 ratio would have had significantly less chromatic aberrations than at F5.6 tested here with reducer.
И 1600 долларов не такие уж и маленькие деньги. Я лично не вижу смысла платить 3300 долларов за esprit 120. Качество фотографий малоразличимо. Я считаю более обосновано вложить эту разницу в стоимости в новую монтировку.
@@TMichman as I own an SVBONY ED102 myself, I would prefer to spend the difference into narrowband filters and a monochrome cooled camera. The SVBONY 122 triplet is "nice to have" (and my HEQ5 mount should easily handle it)
@@3dfxvoodoocards6
If both scopes are native f/7 adding a reducer at 0.7 to get to f/5.6 vs a flattener at 1.0 isn't going to change the CA. It's just changing the focal length and therefore the apparent FOV. You need to correct the image scale to compare the two scopes CA fairly.
It is NOT the same as two scopes with different native f ratios.
Could that side plate on the ES scope allow it to be mounted on a Losmandy D-style saddle? Actually, it looks like it would still be too small. Maybe just to allow for variations in Vixen saddles that may not clamp down enough. Just guessing now. LOL.
Brilliant work! I have the SVBony 550 122, and always wanted to see how it would stackup (pardon the pun) with the SW. Considering the price, I think it holds up very well.
In fact, either saturation must be taken to unrealistic levels to appreciate a meaningful difference or care too much about stars in full-frame corners. Very strong $$$$ difference with the Spirit to obtain a performance increase that may no matter to many people.
I've been doing visual for a few years, I have a skywatcher eq 5, thinking about trying some photography. Any advice on a good scope to start with?
Great video and it makes me happy with what I can accomplish with my AR127. If you would do a deep dive into the Ar127 I would love you forever! No such video exist.
I built my own 5 inch refractor, it's pretty much the first one since it's a doublet but mine cost less than half as much to make, oddly enough it also seems to be on par in terms of color image quality.
If the focuser rotator has right hand screws, you were tightening the "captains wheel". That's a common oversight when you are opposite the rear of the threads.😊 I'm cramming for the eclipse and its my first eclipse here in Texas. What would be your most useful advice for getting the best pictures of it. My equipment, and it's all probably inadequate for the most part. Canon 800 D, HDX 110 mount with Televue Paracorr type 2 coma corrector on Orion 10" Newtonian. I have taken some beautiful deep sky pictures with this setup, in some Bortle 1 and 2 skys. Also I have a William Optics Zenithstar 61mm, with the flat 61 flattener from W.O. Recently acquired QHY 183M with the QHY CFW3 seven position filter wheel. The new camera is for the Orion 10" astrograph. Used astronomy tools CCD suitability calculator to match up the combo. The Paracorr worked like a dream with the 800 D on the 10" Newt, but I'm having trouble finding the connections for the filter wheel to coma corrector for the QHY. I'm thinking my best bet will be the 800 D with the William Optics Zenithstar which is 360 mm focal length. I'm aware it is not the optimally matched pixel scale. I do have the proper T adapter for that. I have been simulating my various combos on Stellarium but none are totally optimal for the eclipse. I also have Neximage five camera and GPCAM 0130M original version for my guide scope. I do not have a photographic Barlow for any of these setups, although I'm aware that's not a problem with the 1000 mm Newtonian astrograph at f/3.9. The Newtonian will give me a good closeup but will probably cut off a lot of corona. The William Optics is a better magnification but slightly under sampled with the APS C sensor in the 800 D. I will be using Thousand Oaks white light solar filters. I know this must seem ridiculous but, any thoughts? Post script; I have SET'n'C on my laptop per your eclipse video 5. Today is the first day I've seen sunshine in two weeks so ill probably go practice in the field next to my apartment. All I need to do now is figure out daytime polar alignment, lug this beast setup out and give it a try.🤪 Is that all?😂 57 year old, lugging an HDX 110 mount around Texas, with a bad back.😬 Thanks for the fantastic, (NO NONSENSE) content. You are one of the few without that. Sincerely, Carl.
Well, I do find it interesting that the ES 127 achro did so well with narrow band filters. Is there an aftermarket field flatterner that can be used on that scope? I have to assume the edges haven't changed any.
So, ES makes two other 127 scopes, the $2,800 FCD100 triplet and the $2,000 127 Essential. I would love to see comparisons with those to the Skywater 120. Also, at a couple of hundred dollars higher than the SkyWatcher, at $3,500 is the ZWO 130 quad. I wonder how that compares to the SkyWatcher for 10mm more of aperture and $200 in price and that fourth element.
How does the 127 mm Explore Scientific achromat compare to the 122 mm Svbony specifically for seeing galaxies (not astrophotography) at 80-120x magnification ? Is there any difference ? Do the galaxies look less sharp, with less contrast and more washed-out ? Thank you!
Hi, is it possible to compare Sky-Watcher Esprit 100mm ED Triplet with Askar 107PHQ 107mm f/7 Quadruplet. Both have similar prices but one of them is triplet the other is quadrupled. Which one is better to buy for astrophoto?
I wonder how well the achro would do in rgb, no lum imaging.
I have a question: What is the best camera you recommend for astrphotography, and my budget is 300$
Star bloat will be still very evident on an achromat scope even with narrowband. Not the Ha but OIII. The stars can be reduced in post processing but trying to match -size the stars to the Ha or the SII filter can be a struggle. and you won't be able to use rgb stars, because even more CA. Ask me how I know. 😊
I wonder how close the three scopes would be after running their data through BlurXTerminator? Can BXT remove the difference between between the Svbony and Skywatcher? ;)
I'm actually impressed with how good the chepo Svbony field flattener performed with a full frame sensor. I would say most of SV122 users will not use a full frame. Most likely IMX571 IMX294 or IMX533 I would say. I've tried both IMX294 and IMX585 so the field will always be flat and illuminated anyway.
I just used APS-C on my svbony 80mm triplet and whatever vignette it had, it was gone after using flats and biases. I'm pretty sure the 5" is even less prone to that.
Hi Nico, I assume that if you compared DUAL NARROW BAND filters like the Optolong L-Extreme, you would expect to end up with fringing on the Explore Scientific, right? Pardon me if that question was already asked and answered. PAUL (jpastroguy)
The Svbony clearly was disadvantaged being used with reducer at F5.6 and the Esprit at F7. Why didn't you use both at F7 since the Svbony is an F7 refractor just like the Esprit ?
The only matched flattener available for the Svbony is the flattener/reducer. So yes I could have used no flattener on the Esprit or the Svbony but I don’t like tests that don’t feel ‘real world’ to me even if they make them technically more matched when it comes to specs. What I mean by that is I would never suggest someone use a doublet/triplet for imaging without the matched flattener if one is available. It makes a huge difference to image quality. There will always be minor differences between telescopes, but for me using the included flatteners makes more sense than not using them. (The explore scientific has no matched flattener available).
Would you use any of them on the AM5?
the SV Reducer is only specified for the DSLR format. Up to there the stars are perfect for me right down to the corners. That should be taken into account. The reduction factor also plays a role...you can see this especially with the Askars.

Feedback
so a 6in shootout is next?
There are two opinions I trust before buying any new equipment. Nebula Photos and Astrobackyard . If y'all approve it, I buy it 😃
I was just looking for a 5" refractor review. Not sure why considering I have 2 of them. Probably just justifying my previous purchases...
with digital cameras its no longer about needing light buckets, thats why refractors are getting so popular with deep sky stuff, so aperture should be considered more about resolution than light gathering...as long as optics quality is good enough you are close to diffraction limited
No comparison should be called complete without also including the Askar 120APO. :-)
Loads review "Oh man the SVBony fans are gonna be so mad!" Reads comments, "Yup there they all are, spectacularly missing the point!"
Great video as ever Nico
For me, it looks like the Explore Scientific narrowband images shows the tightest stars in the upper part of the image. But the lower half of the narrowband image shows tighter stars
in the SkyWatcher. I don't know if this is due to seeing variations or some minor collimation issue. Also the nebula contrast (tadpoles) seems better in the SkyWatcher. Overall, this comparison seems like an argument for the Explore Scientific if you're doing mostly narrowband and want to save some bucks.
I know you are focused on photography but do you ever do visual astronomy comparisons? The reason I ask = I want to get a 4.5 to 5inch Apo for dual use at a dark sky site -> I’m 70:30 visual. The Televue 127mm scope is my current proposed scope. I think it will cover both bases well. Obviously, the three scopes you’ve just looked at are much cheaper though.
I have a TV NP-127, it is an awesome visual scope. I'm mostly visual and just starting down the astrophoto road.
Если вы задаете такие вопросы, то вам не нужен телескоп такого уровня, как вы говорите. Чтобы научиться водить автомобиль, не надо покупать McLaren f1, как первый автомобиль
@@TMichman I already have WOptics 98 flt, a Megrez 72 and an 8 inch dobsonian. I’ve been a visual astronomer for 10 years with intermittent modded DSLR guided astrophotography. The upgrade to a 5 inch Apo has been a longtime coming. Unfortunately where I live, no astronomy club or nearby astronomers.
Not a fair comparison since you used the Svbony with reducer at just F5.6 (instead of it's native F7) and the Skywatcher Esprit at F7.
The only matched flattener available for the Svbony is the flattener/reducer. So yes I could have used no flattener on the Esprit or the Svbony but I don’t like tests that don’t feel ‘real world’ to me even if they make them technically more matched when it comes to specs. What I mean by that is I would never suggest someone use a doublet/triplet for imaging without the matched flattener if one is available. It makes a huge difference to image quality. There will always be minor differences between telescopes, but for me using the included flatteners makes more sense than not using them. (The explore scientific has no matched flattener available).
Wait, if doing RGB with the achromat, wouldn’t you be focusing for blue when shooting blue? Wouldn’t that eliminate or at least minimize the halo? Achromats aren’t incapable of focusing blue, they just can’t do it at the same time as the other colors.
No, because glass quality makes the bigger difference. Achromats don’t use ED (extra low dispersion) glass so the blue still bloats. You can get fairly good correction with an ED doublet.
why would the halo still be there if shooting separate wideband colour filters? is it not a focus difference and if you refocused between colour filters the chromatic aberration would be strongly reduced?
No, because the chromatic abberation is mostly from not having ED glass so the blue channel bloats like that regardless. I can do a follow-up sometime to show practically. Bottom-line: achromats work pretty well for narrowband, not great for broadband whether you go mono or OSC.
@@NebulaPhotos thanks, must have misunderstood something somewhere and need to read up on the details again. I do think a video about how narrowband vs wideband vs one shot colour impacts your telescope selection could be interesting. a RC vs refractor would be cool too. love the videos
I cant find a budget equatorial for my 350 lb telescope. Suggestions ?
There are very few equatorial mounts that can handle 350 lbs and the ones that can are very expensive. How is it mounted now? If it’s in a Dobsonian base, you would probably be better off motorizing that and rotating the camera. Sidereal Technology (SiTech) makes good stuff for that.
@@NebulaPhotos Thank You for the reply. I believe that You are correct. Looking at a modded Dob base, still at the design stage, but I am reusing the precision steel mirror cell, because the aluminum options are expensive. It is very heavy though. Would love to bounce some ideas off of you !
Sadly no Takahashi TSA 120 :(
28:55 well if it doesnt focus that light to the same spot then change focus when you do the shots for that color.
At this point there is literally no point in spending twice as much on a scope , you might as well use the money for electronic filter wheel and focusing.
Should have explained better, it’s not just about how the telescopes focus light, it’s about the quality of the glass used. The achromat does not use ED (extra low dispersion) glass so there will always be that violet blue fringing in the blue spectrum. Doesn’t matter if you use mono+RGB. Mono+ narrowband is different because you are only capturing small slivers of light in deep red and teal green.
Alyn Wallace is no more sir 😔😔😔😔😔
At the beginning you said that visual observers use reflectors (mainly newtonians), because they are cheaper than refractors of that size. Reflectors also don't have any chromatic aberration, basically only coma. Why then should you spend thousands on refractors with high quality glass if for the eq-6 class mount that you used in this video (like the ZWO AM-5 and SW EQ6-R) you can easily put an 8" f/4 newtonian. You'd have a waayyy faster scope than literally any refractor, except for an extremely expensive takahashi (I checked). I really want to understand why you should use a refractor? I think collimation isn't the issue.
No collimation, smaller size, sharper image.
Dual use - a good apo is nice for visual astronomy and photography. Plus no collimation and smaller up to about 4.5 inches
@@wildfury77 the 4.8 inch / 122mm Svbony ED Triplet weighs just 6.4 KG and is 854 mm long.
@@3dfxvoodoocards6 Ok but what if collimation and size doesn't matter for me? And why is it sharper?
@@fouriousbanana6966 the price / performance ratio of the newtonians is of course by far the best but for many people size and no collimation is also very important. And per inch the refractor is unbeatable, a 120-130 mm APO on the planets has a better image quality than a 200 or even 250 mm newtonian.
Where are you going since everywhere is going to be cloudy?
Vermont is my #1 plan at the moment
Skywatcher seems to have an amount of greenish CA tint. I dont think its that easy to say which one is better. More green is just as bad. It would be nice to compare with a newtonian of similar focal length and get a color benchmark.
Except for the faster F stops, I don't see the advantage of refractors over reflectors.
Five inch refractor? Sounds heavy.
Just like your mu- yeah they're heavy for their size compared to other types of scopes.
You must not have actually watched the video, as he weighed each one. Commenting without watching? Sounds lazy.
I understand why they just want to sell small refractors, they are easy to ship and easy to sell... I believe they would have more success by selling reflectors and teaching optics, most of the fun comes from figuring out stuff yourself. These channel is mostly about shooting with 3" refractors for a few minutes and then spending hours in front of a computer.
early!