Which one is the Budget King? Refractor vs Maksutov-Cassegrain

[@damienremwick1059]

What really surprises me about this Sky-Watcher refractor is how well controlled its chromatic aberration is. It is certainly far less than one might expect, so much so that on the Moon I struggle to see it. Mind you, the objective's clear aperture is actually 87mm, which brings the focal ratio closer to f/10.5 than f/10, and that has to help reduce the false colour. And yes, I too find this refractor sharper than my Maksutov-Cassegrain (a Sicong 105mm f/13), though I intend to try flocking that instrument's primary baffle tube to see whether that improves its contrast. Anyway -- thanks, Bogdan, for this comparison and your previous reviews of the two telescopes.

[@lornaz1975]

I have both of these scopes. When I pull them both out to compare them I always put the Skymax back in its case and observe with the refractor.

[@Astronurd]

Depends on what you want to look at.

[@lornaz1975]

@@Astronurd You got a point I guess. But with this small of an aperture it just makes sense to go with the 90mm refractor regardless if its deep sky or planets.

[@evertonporter7887]

I have the Skymax 90mm mak which is great for the Moon and planets, but the FOV is small and even the brighter deepsky objects appear dim. I also have the Skywatcher Equinox 80ED APO refractor which absolutely smokes out the mak in terms of image contrast and overall sharpness.

[@Astronurd]

​@@lornaz1975 The planets are terrible in an achromatic refractor unless you like rainbow colours.

[@k.h.1587]

​@@evertonporter7887have you tried a 40mm plossl on the mak?

[@AndyinMokum]

I have both the SkyMax 102 and its bigger sibling, the SkyMax 127. I use a SkyWatcher EQM-35 PRO SynScan GoTo mount. Both my MAKS are awesome. I highly recommend them for planetary and lunar observation. Fit a planetary camera to them and you've got yourselves a beast.

[@DavidRodriguez-rr4pi]

Es mucha diferencia entre el skymax 102 y el 127?quisiera el 127 pero no tengo plata para el,me alcanza para el 102,tu que tienes los 2,el 102 es bueno?

[@_-pingas-]

I recommend the evostar as not only will it give you a sharper image as he says, you won’t have to worry about blurry views that I have noticed with my 750p.

[@Tataouine854]

Merci Damian pour toutes tes vidéos comparatifs de telescopes👍👍👍

[@Astronurd]

I think that image quality is superior in the Mak, although the contrast as expected is better in the refractor.

[@BjørjaBear]

I have the 127 Mak, but I often find myself grabbing my old 7x50 Tesco binos from the 70s. The Mak is wicked on the moon and the planets, but on the Hyades and the Pleiades, I like the binos.

[@k.h.1587]

Hayades is an extreme example, and pleadies is also one of the largest. There are so many DSOs which can look good in a 127 mak. And with an adapter you can put a 2" diagonal on the mak and get brighter and wider views with a 56mm plossl and 40mm superwide, and 30mm UW80 eyepieces. And no, there is no "vignetting" because the rear baffle is smaller than 2". That is a myth some asshlole started 30 years ago and it has taken hold and keeps propagating

[@paganphil100]

I ordered a Mak102 about half an hour before I found this video....I should receive it tomorrow or the next day from FLO.

[@BogdanDamian]

@paganphil100 Congrats on the new telescope! Let me know how you like it once you get to test it.

[@dhruvkumar7802]

Exactly the video I was looking for🙏🏻

[@evitapepperoni1980]

Thank you for this great video! Is there a Sky-watcher suitable for begginers that is sharp to see planets, brighter elements, comets and deep space elements, with low or none chromatic aberrations?

[@BogdanDamian]

@evitapepperoni1980 For beginners I would recommend either an 150p or 200p Classic Dob. Alternatively a 90mm or 100mm EvoStar refractor would also make a lot of sense for a beginner. Keep in mind that the EvoStar will be excellent for planets, more compact and easier to transport around, but not as good for DSOs when compared to the Classic Dob. The best allrounder would be the 200p Classic Dob.

[@evitapepperoni1980]

@@BogdanDamian Thank you so much, Bogdan! Regarding theses Dobs, I really don't like very much their design... I think I'm going to bet on the Sky-Watcher AC 90/900 EvoStar EQ3-2! :D

[@BogdanDamian]

@evitapepperoni1980 Nothing wrong about that. The evostar is a great telescope. 8f you order one, let me know how you like it. Clear skies!

[@evitapepperoni1980]

@@BogdanDamian Thank you, Bogdan! I will :) I already subscribed your channel to follow your videos! 🙏

[@MarcoRizzinelli]

I have mak 102 in EQ2 i like it very much very portable very light

[@joergbaumann7429]

Super gute Videos 👍👍👍

[@MazzifLOL]

Just mounted my 102mm Mak on ym Sky-Watcher GTi. What a combo

[@BogdanDamian]

@Mazzif Congrats! That is indeed a very nice combo.

[@schoemannh]

Late question: No issues with weight on that mount?

[@michaelklemm-abraham7298]

Resolution of the Skymax is wrong. It is 1.13 arcseconds. This also makes more sense because resolution is mostly dependent on aperture, so the maksutov would have to win.

[@palmereldrich]

Yes FOR stars. For planets an unobstructed aperture wins always UNLESS its figure is poor. Extended objects are not equivalent to stars to compare rez.

[@kennethdorn6393]

Greetings Bogdan, seeking to better understand the difference between two refractors one f/11, the other f/6.5. I get that an f/11 is 'slower' and therefore better suited for viewing planets than DSOs, but does that preclude refractors with f/6.5 being suitable for viewing planets?

[@BogdanDamian]

@Kenneth Dorn Hi Kenneth! With an f6.5 refractor you can definitely view planets just like with an f11 one, but you'll need eyepieces with much shorter focal lengths to achieve the same levels of magnification. Short focal length eyepieces might come with all kinds of constrains, like short eye relief or brightness penalties. The objective lens of a short focal length refractor also needs to bend or refract the light more aggressively to focus the light at the other end of the optical tube. Depending on the quality of the lenses, this might result in less sharper images and more pronounced optical aberrations. On the other hand faster telescopes offer a wider FOV, which make them better suited for DSO observations compared to slow telescopes. Hope this helps.

[@kennethdorn6393]

@@BogdanDamian Thank you, Bogdan, it does help! I will have a follow-up question about choosing a telescope for a given set of needs but first I want to do some research and make calculations based on several considerations that you have addressed in previous videos. Thanks, again!

[@yasserafifi3685]

Great video as usual! i subbed to your channel :). I have a question regarding eyepices. I ordered a 10inch Omegeon dob and I want to get a planetary EP for around 200 euros. which one would you recommend? also for deep space, which one would you recommend for 200 euros. I am considering the SWAN 32 as per your review. But would 40mm be a better/more immersive option? thanks a lot :)

[@BogdanDamian]

@Yasser Afifi Thank you! For planetary observations I would go with the 82° Ar 6,7mm 1,25" from Explore Scientific. If later on you get the feeling that you need more magnification, you can simply get a good 2x Barlow and effectively double the power of that eyepiece. For DSOs I would stick to the SWAN series from Omegon. I'm yet to find a better eyepiece under 300 Euros. Get the 38mm instead of the 32mm. It's just as brilliant and it will offer you a bit more immersive experience. Hope this helps. Clear skies!

[@yasserafifi3685]

@@BogdanDamian thanks a lot for the response. any recommended barlow lens? should i get 2 inch barlow or 1.25?

[@BogdanDamian]

@Yasser Afifi A 2" Barlow lens doesn't make much sense in my opinion unless you have eyepieces with very wide AFOV (82°+) that come in 2" sizes even at short focal lengths. That's why I would get a 1.25" Barlow and here I can recommend the 2x Barlow from Tele Vue. It's one of the best Barlows on the market.

[@k.h.1587]

What you need to consider is your dob is fast, f4.7 or f5 depending on if it is synta or GSO. This poses 2 issues. First being that SWAN and SWA type eyepieces under 200 are not well corrected at the edges in fast scopes. The second being exit pupil. At f5, anything over 35mm is wasted light, if you are young enough to still dilate to 7mm which usually ends by age 50. At f4.7 this goes down to 33mm eyepiece. This affects you in 2 ways, 1, it is wasted light as you are not using the full aperture of the scope if you cant fit the whole aperture, and 2, such extreme exit pupils, anything over 5mm, is only beneficial in 2 areas, dark site viewing, or when using an OIII or UHC filter on dim targets like the veil that need the most light possible. Big exit pupils from light polluted skies give washed out views. Bogdan is in a moderately dark suburban location where it js less of an issue, but rarely is it a good view much over 5mm exit pupil from a light polluted sky. So a better eyepiece for this focal ratio telescope for wide field viewing is actually a 24mm UWA, like the es82, or a used meade 24mm UWA/celestron 23mm axiom LX, which were the same optically as the now more expensive es82. It is also the best of the 2" JOC made 82 degree eyepieces. A less expensive. But even better performer is the 28mm 82 deg UWAN type eyepieces, there are several on the market under different brand names. If you see a company selling 82def eps that only come in 4mm, 7mm 16mm and 28mm, those are the ones and go as low as 200. The 28mm is still a 5.6mm exit pupil at f5 and 5.9mm at f4.7, but that is within range of usefullness for your widest field eyepiece. A cheaper 32mm or 38mm swan is NOT the way to go, certainly not a 40mm! Bogdan is not a master of exit pupil and focal ratio yet, and has described many eyepieces as sharp to the edge, that are anything but. A common thing i notice on youtube. And in astronomy in general, many don't understand these concepts and are not getting the best use out of their scopes. You might also consider an APM 20mm HDC or equivalent, 100deg field of view, same amount of sky/true field as a 24mm 82 deg eyepiece, but at a higher power, 4mm exit pupil. And a 2" barlow makes sense with all of these eyepieces, the best budget option being any of the GSO made 2" 2x ED barlows, which perform almost as well as the old televue BIG barlow. A powermate type is not needed with these type of eyepieces. But note that these are BIG and heavy eyepieces, and the 20mm 100deg is a very tall eyepiece as well, so on the barlow you are ljke a mile away from the scope when looking through it. But the view is worth it.

[@k.h.1587]

​@@yasserafifi3685and for planetary in the 200 range I would probably suggest the 4mm and 7mm 82 degree from the same series, they are about 100 each. And if you can spring for the 16mm you would also get a good mid power DSO/lunar eyepiece

[@linou1968]

hello bogdan hiw are you? im alain ftom Lyon.can you tell me what do uou think about omegon oculaire Panorama II 15mm 2"?do you advice me to buy it? thx

[@BogdanDamian]

@linou1968 Hi Alain! I haven't had the chance to test that eyepiece yet so unfortunately I can't make any recommendations, but based on my experience with the very good SWAN series from Omegon, I believe the Panorama II could be a good eyepiece as well. I added the eyepiece to the list of items to review.

[@linou1968]

@@BogdanDamian ok thx so i buy it

[@BogdanDamian]

@linou1968 Sounds good! Let me know how you like the eyepiece.

[@linou1968]

@@BogdanDamian in à Few days!!

[@linou1968]

Do you have 2° 100 degrés eye pièce?

[@MR.MR.88]

Question about eyeeyepieceses, Does the FoV of the eyepiece affect the qualaty of the object ? for ex. 10mm eyepiece whith 51* fov VS a 10mm whith 100* fov ?

[@BogdanDamian]

@M No, the FOV affects only how much sky you are able to see without moving the telescope. There might however be a indirect correlation between wide AFOV and less than perfect image quality. For example if you have an entry level eyepiece but with a 100° AFOV, than the field of view in all likelihood won't be that flat or sharp around the edges.

[@palmereldrich]

Get the 'budget' ED 100mm from Sky-Watcher at F/9 it is not a good AP scope but visually you'll never be disappointed. You REALLY need to spend 4figures for a great scope experience, unfortunately. And BTW that should be an apo !! Good vids !!

[@evertonporter7887]

I have a few scopes and would sell them all to get one of these refractors.

[@MountainFisher]

For less than $800 I had my C6-N Newtonian's mirror refigured to near perfect .98 Strehl and 1/12th wave and my 4" Explore Scientific apo carbon fiber triplet doesn't give any better a view with a good eyepiece. You don't need to spend four grand. My ES 102 was $2000 on sale.

[@palmereldrich]

​@@MountainFisheryour obstruction reduces that nice primary Strehl. At the eyepiece its half that. Sorry❤ 4figures not 4000$🎉 4000 for EVERYTHING though is about right. Nice scope you've got there🎉🎉❤

[@MountainFisher]

@@palmereldrich A friend in my club uses my 6" reflector for astrophotography. Said it barely even needs a coma corrector. I'm more visual than into taking pictures. I asked my son for the 102 Astro Tech and he bought me the carbon fiber ES triplet on sale. I used it after a dust clearing rain to get an awesome photo of C80 the Omega Centauri Cluster. Only rises to 10 degrees at my 32 latitude.

[@georgesimeonov2008]

Did you maybe make a mistake in the resolving capacity of the Skymax? All sources show 1.13 arcsec.

[@kevingumfory]

I looked at a newt mak for a wk or 2 ... particularly the carbon fiber one. I forget the manufacturer. Man that thing took beautiful beautiful pictures. I can't find it tho in an 8" or more aperture.

[@BogdanDamian]

@kevingumfory I believe Orion Optics UK offers large Maks made out of carbon fiber. They sure are sweet and also very expensive.

[@AmatureAstronomer]

Interesting.

[@palmereldrich]

Do an apo to Maksutov comparison Bogdan❤

[@BogdanDamian]

@palmereldrich Working on one right now. Stay tuned 🙂

[@Astronurd]

I have owned the 127 Mak and now own the 150 pro.I compared my 130 triplet refractor with the 150 Maksutov. There's really nothing between them. The triplet had slightly better contrast but the Maksutov slightly more resolution. That's why Maks are called the poor mans apo. Any Maksutov that is collimated will beat an achromatic refractor of similar aperture every time.

[@k.h.1587]

When looking at most star clusters, a 90mm f10.1 should not show noticeable color, what you describe is what happens when looking at stars bright enough to have names , or maybe the pleadies. I haven't used this particular scope, but have owned synta 80mm f11, GSO 90mm f11, and 2 synta 4" f10 (c4r that got stolen, and a celstron 102 f10 from a costco GT scope to replace it). They have all been pretty awsome on star clusters, and even saturn looks really good with barely if any color. Jupiter and the limb of the moon always shows a little color, and i rarely spend time looking at bright stars, so for the money I dont find it too offensive. I have owned several apo and semi apo refractors over the years, sold or returned a few, and had my best ones stolen eventually. From celestron 80ED, to william optics 80 FD, astrotech 66ED, and televue 101 and pronto. But I still loved my C4R and nexstar 80gtl long achromats. I had modified my 80gtl with a 2" GSO focuser that was identical to what came on the GSO 90mm f11, it didnt cost much from one of the surplus dealers at the time. There are probably 2" focusers that will fit that scope as well, and it is a worthwhile upgrade and doesnt have to cost too much if you go rack and pinion. One of the things i love to do with long achromats is use 2" eyepieces for wide field deeo sky. The f10 and slower work real well with budget UW80 and SWA eyepieces I also had orion 90 and 127 maks, a celestron 127 mak, and currently have an etx90 tube so I am no stranger to maksutov and I like them very much. I would still have the celestron 127, but that was lost in my more recent string of bad luck when it and some other scopes and mounts were in my van when it was stole-pounded by a corrupt city and county.