I'm selling my Skywatcher SkyMax 102

The SkyMax 102 from Skywatcher is a great Maksutov-Cassegrain telescope I had the pleasure observing the night sky with. But now it needs to make room for a new telescope - a 4” ED refractor. Check the video out to find out more!
⬇️ More information down below ⬇️
More information on the Skywatcher SkyMax 102 WITH collimation screws
Review: • Travel with your teles...
Buy here (affl): amzn.to/3PbpiKl
More information on the Skywatcher Evostar 90/900
www.astroshop....
More information on the Svbony SV550 122 APO
amzn.to/3sHzq5Z (affl)
More information on the Svbony SV503 102ED
amzn.to/481FuGp (affl)
Handlebar for the SV503 102ED:
www.teleskop-e...
Omegon ProDob 12”
Review: • Is a 12" Dobsonian tel...
Buy here (affl): tinyurl.com/2p...
NASA Apollo Saturn V Lego set:
amzn.to/40jhdrf (affl)
Thank you for your support!

[@Megawatt]

It’s nice to have a good grab-and-go setup, but for serious observing I always use my 12” Dob.

[@ITProjectManagerMan]

The EvoStar 100mm is a wonderful telescope. I wish I hadn’t sold it. I must have been crazy that day. Really enjoy your video’s. You have a new subscriber. 😊

[@MountainFisher]

Central obstruction is the reason why you cannot get near maximum with any reflector. Look at the % of the central obstruction and deduct that from theoretical maximum is a good rule of thumb. Your secondary obstruction on the Max is 9% by area, so you're going to lose at least 9% of 200x and you started having issues near 170x, about right when you add in other things like what you lose in your diagonal mirror plus the Sky-Max is only 94% reflectivity.

[@BogdanDamian]

@MountainFisher That is a very good point. I guess all these small factors combined are reducing the visual quality quite significantly.

[@MountainFisher]

@@BogdanDamian When I refigured my reflector's primary mirror it came out near perfect, but the optical engineer who did the work on my mirrors to 96-97% reflectivity told me even in space I'd never get 300x out of my 150mm simply because of those factors. He said count about 3/4 of double aperture and then it only comes down to seeing conditions. Several guys in my club get those big Obsessions from 500mm or larger just for dark sky viewing at 400x to 600x. They said having such a big aperture is wasting their optics in light polluted skies and it would be best to get a refractor for viewing. Astrophotography is one thing, but visual _needs_ dark skies. I live near Bortle 2 and that is where I use my 150mm the most, but always great for the Moon.

[@wiktorwektor123]

@@BogdanDamian Maks, Cassagrains, Shmids and Newtonian scopes all have central obstruction, you have substratct this from your aperture size to get maximum viable magnification. No refractor has this obstruction, that's why smaller apertures in refractor can give you better magnification resoults with smaller aperture. Also, the longer focal length in refractor, the better chromatic abberation reduction.

[@stevenlarkin1706]

This does not apply when the primary mirror is deliberately oversized to produce an advertised aperature size.

[@davidsussman7476]

I own the SV503 80ED, and it’s my preferred grab-and-go scope. Rotating focused, dual-speed, smooth as silk. I use it manually on my Vixen Porta II Mount. Nice channel!

[@Astronurd]

If you don’t mind the CA.

[@joeshmoe7899]

​@@Astronurdyeah. That's 51 glass, not 53. Is it really "ED"? I'll stick with my celestron 102 az achromat. Got it for 50 bucks, open box.

[@allnamesaretaken]

@@joeshmoe7899 Yes, its ED, this telescope has been around with many different names, its well tested. As for FPL51 vs FPL53, i challenge anyone to show me a difference in real world usage, both visual and astrophotography, i own the SV550 80 APO, i have tested this against a more expensive Sky-Watcher Esprit 80 ED PRO many times (a friend owns it) and saw no difference. On paper fpl53 is a bit better than fpl51 but most people would be disappointed in a side by side comparison. I also own a Celestron Astromaster 90mm, nice scope, the only good one out of them, the 102mm is awful at high power, too much loss of detail on planets but for the price you got it, it was a steel.

[@robertsonsid]

@@joeshmoe7899 102 F6.5 or the 102 F9.8?

[@amarbirk8987]

I also have a 80mm ed, 127mm mak and find that the 80mm is a lot brighter and sharper. I am new to this so please excuse my lack of knowing

[@MrCornweda]

Long focal length refractors have always been good on planetary observations. They are also very easy on eyepieces. You can use some very inexpensive eyepiece that give good views in F10 or above telescope. I am not sure why they are not more popular as they were in the past.

[@sciencecompliance235]

Physical size is probably the reason.

[@studentjohn35]

Good improvement to the 102Mak: replace the OEM primatic diagonal with a mirror diagonal.

[@peterwarden7471]

Greetings from Australia. I'm new in this hobby. In Australia cost the named Evostar 3 times of the Sky Max 102. It's a Difference from approx 800$ to approx 2,800$ (Australian Dollar).

[@BogdanDamian]

@peterwarden7471 Hi! That is way too expensive. Go for the SkyMax 102. Just make sure to get the model with collimation screws at the back.

[@leonidcechmistro7351]

Nice video Bohdan! I went from an Astromaster 90mm to a William Optics ZenithStar 81mm, ok the price point is higher about ($1200 Can) but my views were improved. It’s probably heavier, coming in at about 8lbs….

[@BogdanDamian]

@leonidcechmistro7351 The Zenith star 81 is a sweet refractor. How is the CA compared to the Astromaster?

[@leonidcechmistro7351]

@@BogdanDamian there is no ÇA evident in my eyes, you really can’t compare the two, I really loved the Astromaster, but in pictures that I made with my phone of the moon, you can clearly see the difference between the two telescopes.

[@IvanVazquezS]

I'm a bit confused about the upgrade. since the focal length that you had with the skymax was 1300mm F12, and now you will have only 700mm F7, meaning if you want to get planets as big as with the Skymax you need to use a barlow 2x to get 1400mm F14, which leaves you kinda at the same point (or even worse, because its darker). I know you already sold the skymax but a comparison between the images of the 2 telescopes (the SVBONY with the barlow 2x) would have been fantastic to understand how this is an actual upgrade!

[@BogdanDamian]

@ivanVazquezS I will offer a more detailed comparison between the two in the upcoming review of the sv503. I did test them side by side extensively. But without wanting to give away too much, I can tell you that at the same magnification the sv503 can offer considerably better views.

[@jair_rillo]

Thank you and congratulations on your channel, you always bring very important information. I love the series where you showcase eyepieces. However, regarding the upgrade of your telescope, I have a question: What is your main goal when you transport the telescope? Is it for planetary observation/DSO or for astrophotography? Although I understand that transporting the 305mm may not be easy, it must be amazing for planetary observation. For astrophotography, I think you could consider an APO with apertures smaller than 4''. How about a William Optics RedCat 71? (I know the budget is higher, but it's excellent for astrophotography).

[@BogdanDamian]

@jair_rillo Thank you, I'm glad you enjoy my videos! With this upgrade I was looking to get even more optical performance out of a 4" platform while keeping the cost below 750 Euro. I got it mainly for planetary observations and also as possible platform for astrophotography, but this is more of a distant idea. While a triplet design would certainly offer better views, the jump in quality over a quality doublet isn't actually that big, especially for visual astronomy. Our eyes are much less sensitive than a dedicated camera. So I feel that the effect of diminishing returns becomes significant once you go past a certain threshold. For 4" it's somewhere around the 750 Euro mark, at least in my mind. Since I can seldom observe with more than 200x magnification due to seeing conditions, a 4" telescope that feels conformable sitting at this value, is in my eyes ideal. While the 12" dob is great for planetary observations, it's also overkill most of the time. Where it shines though is DSO observations.

[@k.h.1587]

That mak was suspect. The synta 102s had the 6 screw collimation screws on the back, same as the 90, 127 and 150 and i assume the 180. Also the front cell was flat sided same diameter as the tube, and yours was different. A cheapened out version i assume

[@Astronurd]

You messed it up by loosening the mirror cell. You shouldn’t have done that. The new SV scope uses FPL51 glass and has a degree of CA. I sold mine due to being sensitive to CA.

[@buituonglam]

Hello Bogdan Damian, I am a newbie. Just wonder whether or not your Skywatcher SkyMax 102 is still available for sale? and any recommended motorized mount?

[@BogdanDamian]

@buituonglam Hi! I don't have the SkyMax anymore, but there is a newer model available on amazon that has collimation screws at the back (amzn.to/3Fb0k9f). As for the motorized mount I recommend the AZ GTi also from Skywatcher.

[@buituonglam]

Hi @@BogdanDamian, thank you for the recommendation!

[@gonguereguere2404]

The maks come very often out of collimation. The vendor should check it before selling.

[@AlbertoGirardi747]

How have the Saturn observations been during opposition? I had a few very good nights anfew day before. I used up to 420x, and the image was still very acceptable. Then there were clouds for more than a week. Now no clouds byt awful seeing

[@BogdanDamian]

@AlbertoGirardi747 That sounds great! Unfortunately I had only bad weather that whole weekend and a few days after that. Before the opposition event I had some nice observing sessions though with decent seeing conditions. I got to appreciate my new 4" refractor a lot more.

[@AlbertoGirardi747]

@@BogdanDamian sorry to hear about the bad weather. Luckily Saturn is still in a very good position, and Jupiter is coming up. I saw the red spot, which I had never seen before on my older telescope.

[@anata5127]

What about TEC 140mm?

[@toneotoneo]

For next upgrade try a Takahashi FC-100DZ ;)

[@Stephen-gp8yi]

Hi bogdan totally unrelated would it be ok to use a 9mm eyepiece with a 3xbarlow to look at saturn with my 8 inch dobsonian which would put it at 400xmagnification.I know the limit is 408 but I have a feeling it will affect the focus if to much power?I can’t seem to find my 2xbarlow.thanks🤙🏻

[@MountainFisher]

No, see my other comment about reflector. Your mirror at best is 94% reflectivity and your central obstruction is 8% by area.

[@palmereldrich]

Hi !! Look for 200X to 250X power as seeing usually puts limits past that and you'll use that much more often even though it MIGHT be able to do it SOMETIMES very rarely. Good scope❤ Good hunting🎉

[@Stephen-gp8yi]

@@palmereldrich thanks appreciate it I’m only a beginner✌️

[@BogdanDamian]

@Stephen-gp8yi The 9mm with a 3x Barlow might be too powerful for normal visual observations. Try and keep it under 300x for best results. A 2x Barlow would be ideal.

[@Stephen-gp8yi]

@@BogdanDamian thanks bogdan!

[@knightclan4]

Great video

[@lemures87]

How to collimate it?

[@BogdanDamian]

@lemures87 Mine didn't come with collimation screws at the back which made the hole thing rather hard to do. What I did was to defocus on a bright point of light, like a pin needle whole in a sheet of paper held against the window light (not the Sun!). Then loosening the whole mirror assembly a very tiny bit and finally very carefully moving it while checking the image inside the eyepiece. It's very tricky and you might make everything worse, which is why I recommend bringing it to a specialist, sorry.

[@ranjitkoothuparambil9782]

will you still recommend skywatcher evostar 90 900 az3 for beginners ?

[@BogdanDamian]

@ranjitkoothuparambil9782 Absolutely, but get the version with the EQ mount instead.

[@Sw87sw87]

Can anyone recommend a case or bag for the sv503 102ed?

[@BogdanDamian]

I got this one only with blue accents: amzn.to/3LhoQc1 I also kept the original foam pieces the telescope got delivered with. They fit perfectly inside the bag.

[@Sw87sw87]

@@BogdanDamian Just recently got this telescope. Thanks a lot!

[@AnotherAmateurAstronomer]

Am currently using a Bresser 102mm f4.5 refractor (6.16 pounds). Using my SVBONY SV405CC Cooled Camera, I can photograph all of M31 and M42. But, the planets look like stars. So, I am thinking of buying a SVBONY Telescope MK105 Maksutov-Cassegrain (4.83 pounds) for small deep space objects and planets. Both work with my Sky Watcher AZ GTi go to mount (11 pound capacity) with camera and finder scope.

[@BogdanDamian]

@AmateureAstronomer I believe the problem why the planets look so small is that the magnification isn't high enough. If you have the possibility, try using a 3x or 4x Barlow first it might help in this regard. The MK105 thanks to the much longer focal length should perform well on planets. It might, however, also need a 2x Barlow to produce a decent resolution on the planets.

[@AnotherAmateurAstronomer]

@@BogdanDamian I have a 25mm eyepiece and my telescope has a 460mm focal length. This produces a magnification of x18. A x2 Barlow lens gives me a x36 magnification and Jupiter looks like a small white disk with 4 little stars around it. With a optical tube of 1325mm focal length, my 25mm eyepiece would give me x53 and with a x2 Barlow x106, which is much larger.

[@BogdanDamian]

@AmatureAstronomer Are you using your camera in combination with the 25mm eyepiece? If so, try using it without. Insert the camera into the 2xBarlow and try capturing a planet this way. For visual planetary observations the 25mm eyepiece is too weak indeed. You'll need a 3mm one for best results.

[@AnotherAmateurAstronomer]

@@BogdanDamian asked, "Are you using your camera in combination with the 25mm eyepiece?" No. Planetary observation? 3mm? I only have 10mm, 25mm, 26mm and 40mm. No 3mm.

[@DouglasLippert]

You can’t have a free lunch. For planetary and lunar observation you can’t beat a Mak. For DSO? Refractors/reflectors beat the Mak. A serious amateur needs at least two telescopes or one with compromised. (A SCT scope as the compromise(

[@palmereldrich]

Apo doublet SD glass SLOW Then post😮😮😮😮

[@stevenlarkin1706]

An APO refractor beats a maksutoff.