With all conditions being equal, I would think the dob of the same size as the SCT would have clearer imaging due to smaller secondary size (mirror), and less rays bouncing around mirrors before reaching your eyepiece. No right angle diagonal and faster f-ratio with a Dob.
I make my way into mountains nearby to use my CPC-1100 SCT, and the struggle against dew there is very real on almost any given night. Dew bands cranked to the highest settings, Ive still only got about 4-5 hours after sunset until the battle is lost and I shut the whole operation down. Cant say how much different that would be with a Dob, but just by the fact that there are fewer ocular surfaces (lenses, glass and mirrors), that can dew over, I imagine it would be an easier fight.
Big dob will definitely buy you more time.eepnwith a fan fitted but otherwise I've been in same boat here in Highlands. Dew heater at max in mid winter
Not sure what an f6 means but I just bought a skywatcher 200p and somehow managed to show my 7 year old daughter Jupiter within and hour of setting it up out the box . Don't know if that's lucky or terrible but I'm properly impressed with it
I just got a nexstar8 SE...but what does the SE stand for?? I also got a 8mm Radian that is nice...did you know the name Radian is because the special glass used is slightly radioactive....if you look at them in a really dark place you can see they put off a glowing green light, but it's all good 😊
I bought a Meade 10" Lightbridge telescope a few years back, the views were phenomenal, but at around 65 lbs., the telescope was extremely bulky, although it broke down and set up pretty easily, but it was a real bear taking up and down stairs as I lived on a second-floor condo. If you are an older individual like me, and you are thinking of getting a larger Dobsonian, you should consider weight if you have any back issues. you might be better off getting the Nexstar, at under 40 lbs., its considerably lighter to carry around. Although I will say the dew issue is a definite concern.
I'm in the same boat. My 10" dob is 44 years old and it feels like it's putting on weight. I'm considering going to an 8" SCT just for the portability. The telescope that shows you the most is the telescope you use the most!
We got the exact same dob a month or two ago as our first telescope - haven't really had the clear skies to view much other than the moon at the moment. We love the scope but like you said, for a beginner it can be tiresome trying to find objects but we have enjoyed trying nonetheless! I was actually looking at the 8SE given its goto system and portability but your review has made me question my thinking, at least until we have had a real chance of putting the dob to good use. 8SE is available on sale at the moment, for several hundred pounds off so it would be a good time to get one!
Celestron recently released 8” & 10” dobs that use their Starsense technology app. It’s super helpful for navigating the sky, I’ve seen some great things I never would’ve known were there.
Im a newbie and gonna buy first scope. Want to get one of these two. They are almost the same price now. I also am not familiar with the night sky. Should I just get the celeron? Which gives better image quality for planets and galaxies?
@@elchappo1320Both are good for planets but the dubsonian is better for deep sky objects like star clusters and galaxies because of its f/5 focal ratio like he said in the video. If you don’t know the night sky and have the money, get the Celestron, but if your willing to try and learn the night sky your yourself and want the best and crisp image, I would get the dub.
The SE can take a hyperstar adapter.. Which makes it a deep space telescope. In a short body... I got the SE6 with a Hyperstar. It turns it into an f2. Which gives me he best of both worlds in one telescope...
@@ZeeZee9 Depends if you move it around a lot... I preferred the 6" as that was the point they make the Hyperstar for the SE models for $499/00 new. If you get the 8" it cost $1,000.00.. But it depends on you. As I don't tell people what to buy. As I have no idea how much they can afford to spend. I would go look at both of them. See if you think you really need an 8".. If you can find one used. Then go that way. As I just seen an 8" used selling for $600.00 US. It was still in the box.
An 8" dob (f6...), with a magnetic clinometer on top of the tube, and a geological compass on the base plate. You got a great setup that you can point fast and easy. Clinometer 20$ amazon Geological compass 20$ amazon (the one with east and west flipped, and degree ring anti clocwise numbers).
Interesting Daniel do you know of any video or content that shows you how to do this with a magnetic clinometer( I have a klein magnetic clinometer already) can you link the geological compass with east and west flipped and degree ring anti clockwise numbes, i cant seem to find that one) thanks for your feedback, I want to do this on my 8" & 10" Dobsonians
@@HumbleLife8 I had issues with my compass because it was too sensitive with metal. The lazy susan distorded the reading of azimuth. The idea is good, but I need to find another model, less sensitive to the telescope metal parts. I tried with a map compass (transparent plastic), it was good but the reading was too difficult in the dark. I ordered another compass, as soon as I can try it I will let you know. I stick my magnetic clinometer between the finder and the eyepiece holder in the center of the OTA.
@@danielbarbieri8199 Hey thanks for responding, I look forward to hearing your solution to this, if I find one before I will also share with you, GOD Bless Daniel, Clear Skies brother!
7:50 You never needed f / 10 or higher? Most planetary observations and some lunar usually happen at f / 10 to f / 20, which are major beginner targets. That's why f/15 Maks are often called "planet killers". Fortunately, getting a 2x to 3x Barlow will take your f / 6 scope up to f / 12 to f / 18.
The Dobsonian has a much smaller focal length - less than half, (and hence magnification) than the Schmidt-Cassegrain, so the latter is better for planets.
The 150mm is not any more portable than the 200mm, the tubes are almost the same length, same focal length just skinnier and lighter. Also the 200 is an f6 not an f5. Both the 200 and the c8 can use 2" eyepieces, fitting m81 and m82 does not need a focal reducer if you have a wide field 2" eyepiece. An f6.3 reducer makes the c8 almost as short a focal length as the dob, but that is where the dob still wins for widefield since it can handle a 2" eyepiece that uses the full 2" field avaliable where a 6.3 reduced sct can only go a little wider than what is possible with 1.25" eyepieces before vignetting is noticeable at the edges, up to maybe a 30mm superwide where the dob can handle a 40mm superwide or 31mm ultrawide. But another issue is the f6 scope will require the fancy well corrected eyepieces to be sharp at the edge where the f10 scope can get away with the cheaper (or older) widefield designs. F6 is not as bad as f4 or f5 in this regard, but edge astigmatism is much more pronounced than it is at f10. Something people who never go beyond a 1.25" plossl set don't have to worry about, but if you are still in that catergory you are not experiencing the best that visual astronomy has to offer
The lower the focal ratio or "f-number", the wider your *true* field of view will be with *all else being equal* . If the latter is not true, then it might be wider, or maybe not, depending on how big your telescope is. Generally, the larger your telescope is, the narrower its field of view becomes, assuming only 1.25" or 2" eyepieces are used.
@@weedshoes5089 That's why I said "with all else being equal" and that it depends on the "size" of the telescope. I was describing it from a certain point of view. Of course, you're right that focal length takes all of that into account. However, it doesn't take absolutely everything into account, because the maximum true field of view also depends on the diameter of the focuser and the eyepiece barrels (measured on the inside, of course), not just the focal length. The maximum true field of view is equal to (180 × focuser diameter in mm) ÷ (π × telescope focal length in mm).
Most modern 😢Celestron 8" SC's let you replace the secondary mirror with a CCD camera, turning it into an f/2 telescope. This feature is called Fastar or Hyperstar.
Many thanks for this review. Very informative! I’m shopping for my first telescope. I’m mainly considering the 12” flex-tube Goto dob from Skywatcher, but since it’s not easily transported, a vendor suggested the Celestron NexStar SE 8” or the NexStar Evolution 9.25". The vendor says these two NexStars or comparable to the 12” dobsonian, but I’m not convinced. Any thoughts?
They're full of it. Having a 12" aperture over the others makes a significant difference (depending on what you're trying to observe, of course). The Dob is also capable of providing wider true fields of view. Of course, it has some disadvantages compared to the NexStars, as well, but they're not comparable optically. SCTs are *not* better than Newtonians per aperture. They were just trying to sell you something more expensive.
@@midnitelitecompany You don't touch them things with a cloth.. You use a camera lens brush and blower. I seen people use a cloth and it had one speck of dirt on it. Instant scratches like sand paper was used...They had to send it off to polish it out.
I’m sorry to hear that. Seems out of reach to most people then 😕 On the upside, you guys have some of the best observatories in the world and they are sometimes open to the public, as I understand. I wish I could experience that.
06:00: That's not correct. Focal ratio (aka "speed") has nothing to do with how wide or narrow the view is, or consequently, how much it magnifies the target. This is determined by the focal _length._ The focal ratio is simply the focal length divided by the aperture. What the focal ratio does, is determine how much light is being gathered in a given amount of time. Lower focal ratios gather more light in the same amount of time, the same amount of light in less time, or a combination thereof. If you double the diameter of your telescope, while keeping the focal length (magnification) the same, you gather 4 times as much light in the same amount of time. This will decrease the required exposure time for the same "quality" of photo, and will make fainter objects easier to see during visual observation. However, the area that fits in your view remains exactly the same. The only time your statement holds true is when comparing telescopes with the same aperture. In those cases, a lower focal ratio will indeed indicate a wider field of view. But that's only because at the same aperture, a lower f-ratio is a consequence of a lower focal length. It's not the focal ratio that is responsible for the larger or smaller magnification; it's the focal length. Take for example a 400mm focal length scope with a rather smallish 80mm (3.15") lens. This has a focal ratio of 5. However, so does a 2000mm telescope with a big, fat 400mm (15.75") lens. The 400mm scope will allow you to image larger nebulae though, whereas the 2000mm scope will be too narrow, but an excellent scope for planetary observation.
@@velkylev4217 Damn, your arguments are convincing. In light of the evidence you provided, I fear I have no other choice than to reconsider my statements. But just for the retards who didn't quite catch what you're on about, could you perhaps explain it again in terms they could understand as well? I mean, after a thorough study of your counter arguments, I believe I could to it myself, but I'm sure you could explain it way better than me. Just repeat the arguments you presented above, but dumb them down for a general audience.
You made great points! I’m a newb and just purchased the dob in your video!
How have you been liking it so far? Are you able to see Jupiter and Saturn pretty well?
With all conditions being equal, I would think the dob of the same size as the SCT would have clearer imaging due to smaller secondary size (mirror), and less rays bouncing around mirrors before reaching your eyepiece. No right angle diagonal and faster f-ratio with a Dob.
I make my way into mountains nearby to use my CPC-1100 SCT, and the struggle against dew there is very real on almost any given night. Dew bands cranked to the highest settings, Ive still only got about 4-5 hours after sunset until the battle is lost and I shut the whole operation down. Cant say how much different that would be with a Dob, but just by the fact that there are fewer ocular surfaces (lenses, glass and mirrors), that can dew over, I imagine it would be an easier fight.
Big dob will definitely buy you more time.eepnwith a fan fitted but otherwise I've been in same boat here in Highlands. Dew heater at max in mid winter
I would go for the Dobsonian scope!
skywatcher 8 inch dob is actually f6 focal ratio not f5.
True, you can see d=200mm and fl=1200mm on the side at 6:20
Not sure what an f6 means but I just bought a skywatcher 200p and somehow managed to show my 7 year old daughter Jupiter within and hour of setting it up out the box . Don't know if that's lucky or terrible but I'm properly impressed with it
My 8SE with a dew shield never had any dew. Perhaps I got lucky picking dry night end of autumn. Nice comparaison
Yea I guess local conditions also make a big difference. Glad you've been able to keep it passive without the heater.
@@modulouniverse7029 I juts upgraded to the Evolution 9.25 and very much looking forward to first light.
@@Ajajambo enjoy
I just got a nexstar8 SE...but what does the SE stand for??
I also got a 8mm Radian that is nice...did you know the name Radian is because the special glass used is slightly radioactive....if you look at them in a really dark place you can see they put off a glowing green light, but it's all good 😊
I would take the dobsonian
I bought a Meade 10" Lightbridge telescope a few years back, the views were phenomenal, but at around 65 lbs., the telescope was extremely bulky, although it broke down and set up pretty easily, but it was a real bear taking up and down stairs as I lived on a second-floor condo. If you are an older individual like me, and you are thinking of getting a larger Dobsonian, you should consider weight if you have any back issues. you might be better off getting the Nexstar, at under 40 lbs., its considerably lighter to carry around. Although I will say the dew issue is a definite concern.
I'm in the same boat. My 10" dob is 44 years old and it feels like it's putting on weight. I'm considering going to an 8" SCT just for the portability. The telescope that shows you the most is the telescope you use the most!
How about collimation ? Which one is easier to collimate ?
We got the exact same dob a month or two ago as our first telescope - haven't really had the clear skies to view much other than the moon at the moment. We love the scope but like you said, for a beginner it can be tiresome trying to find objects but we have enjoyed trying nonetheless! I was actually looking at the 8SE given its goto system and portability but your review has made me question my thinking, at least until we have had a real chance of putting the dob to good use. 8SE is available on sale at the moment, for several hundred pounds off so it would be a good time to get one!
Celestron recently released 8” & 10” dobs that use their Starsense technology app. It’s super helpful for navigating the sky, I’ve seen some great things I never would’ve known were there.
Im a newbie and gonna buy first scope. Want to get one of these two. They are almost the same price now. I also am not familiar with the night sky. Should I just get the celeron? Which gives better image quality for planets and galaxies?
@@elchappo1320Both are good for planets but the dubsonian is better for deep sky objects like star clusters and galaxies because of its f/5 focal ratio like he said in the video. If you don’t know the night sky and have the money, get the Celestron, but if your willing to try and learn the night sky your yourself and want the best and crisp image, I would get the dub.
I decided to get the stellalyra 8 inch dob over the skywatcher as it has a right angled finder a fan and superior eyepieces for slightly less money!
The SE can take a hyperstar adapter.. Which makes it a deep space telescope. In a short body...
I got the SE6 with a Hyperstar. It turns it into an f2. Which gives me he best of both worlds in one telescope...
Would you rather use your current setup with a 6SE or get a 8SE? Which one is better?
@@ZeeZee9 Depends if you move it around a lot... I preferred the 6" as that was the point they make the Hyperstar for the SE models for $499/00 new. If you get the 8" it cost $1,000.00.. But it depends on you. As I don't tell people what to buy. As I have no idea how much they can afford to spend.
I would go look at both of them. See if you think you really need an 8".. If you can find one used. Then go that way. As I just seen an 8" used selling for $600.00 US. It was still in the box.
@@WizzRacing ok thanks. It sounds like your setup is much cheaper and offers similar views.
@@WizzRacing Hi, may I ask one more question? Do you think your current setup (6SE + Hyperstar) is better than using the 8SE alone?
@@WizzRacing Also, is the Hyperstar adapter just for astrophotography or also for naked eye viewing also?
An 8" dob (f6...), with a magnetic clinometer on top of the tube, and a geological compass on the base plate. You got a great setup that you can point fast and easy.
Clinometer 20$ amazon
Geological compass 20$ amazon (the one with east and west flipped, and degree ring anti clocwise numbers).
Interesting Daniel do you know of any video or content that shows you how to do this with a magnetic clinometer( I have a klein magnetic clinometer already) can you link the geological compass with east and west flipped and degree ring anti clockwise numbes, i cant seem to find that one) thanks for your feedback, I want to do this on my 8" & 10" Dobsonians
@@HumbleLife8
Clinometer
ua-cam.com/video/q26eFp2V-bw/v-deo.htmlsi=rP3-9YxOEtIhZ2XU
@@HumbleLife8
I had issues with my compass because it was too sensitive with metal. The lazy susan distorded the reading of azimuth.
The idea is good, but I need to find another model, less sensitive to the telescope metal parts. I tried with a map compass (transparent plastic), it was good but the reading was too difficult in the dark. I ordered another compass, as soon as I can try it I will let you know.
I stick my magnetic clinometer between the finder and the eyepiece holder in the center of the OTA.
@@danielbarbieri8199 Hey thanks for responding, I look forward to hearing your solution to this, if I find one before I will also share with you, GOD Bless Daniel, Clear Skies brother!
Just clean that beauty.
C8 is a planet killer, but to your point, when focal reduced, it does pretty well. The 8” Dob is geared to sweeping across the sky.
7:50 You never needed f / 10 or higher? Most planetary observations and some lunar usually happen at f / 10 to f / 20, which are major beginner targets. That's why f/15 Maks are often called "planet killers". Fortunately, getting a 2x to 3x Barlow will take your f / 6 scope up to f / 12 to f / 18.
Exactly! I used a 7” Mak f/15 and got incredible views of Saturn and its moons. Long focal length for planets is a must!
Both are predominantly Alt-Az though the 8SE can be placed on a built-in wedge.
The Dobsonian has a much smaller focal length - less than half, (and hence magnification) than the Schmidt-Cassegrain, so the latter is better for planets.
Dob has a focal length of 1200mm the Nextstar has 2000mm 🤔
Great video and thank you for the advice.
Great video, thanks!
I've got an 8" SCT. I need an 8" F/6 dob.
Why so?
The 150mm is not any more portable than the 200mm, the tubes are almost the same length, same focal length just skinnier and lighter.
Also the 200 is an f6 not an f5.
Both the 200 and the c8 can use 2" eyepieces, fitting m81 and m82 does not need a focal reducer if you have a wide field 2" eyepiece.
An f6.3 reducer makes the c8 almost as short a focal length as the dob, but that is where the dob still wins for widefield since it can handle a 2" eyepiece that uses the full 2" field avaliable where a 6.3 reduced sct can only go a little wider than what is possible with 1.25" eyepieces before vignetting is noticeable at the edges, up to maybe a 30mm superwide where the dob can handle a 40mm superwide or 31mm ultrawide.
But another issue is the f6 scope will require the fancy well corrected eyepieces to be sharp at the edge where the f10 scope can get away with the cheaper (or older) widefield designs. F6 is not as bad as f4 or f5 in this regard, but edge astigmatism is much more pronounced than it is at f10.
Something people who never go beyond a 1.25" plossl set don't have to worry about, but if you are still in that catergory you are not experiencing the best that visual astronomy has to offer
The lower the focal ratio or "f-number", the wider your *true* field of view will be with *all else being equal* . If the latter is not true, then it might be wider, or maybe not, depending on how big your telescope is. Generally, the larger your telescope is, the narrower its field of view becomes, assuming only 1.25" or 2" eyepieces are used.
nah. Focal length determines field of view.
@@weedshoes5089 That's why I said "with all else being equal" and that it depends on the "size" of the telescope. I was describing it from a certain point of view. Of course, you're right that focal length takes all of that into account. However, it doesn't take absolutely everything into account, because the maximum true field of view also depends on the diameter of the focuser and the eyepiece barrels (measured on the inside, of course), not just the focal length. The maximum true field of view is equal to (180 × focuser diameter in mm) ÷ (π × telescope focal length in mm).
Most modern 😢Celestron 8" SC's let you replace the secondary mirror with a CCD camera, turning it into an f/2 telescope.
This feature is called Fastar or Hyperstar.
but with the Dob, you can get set up a lot faster
Many thanks for this review. Very informative! I’m shopping for my first telescope. I’m mainly considering the 12” flex-tube Goto dob from Skywatcher, but since it’s not easily transported, a vendor suggested the Celestron NexStar SE 8” or the NexStar Evolution 9.25". The vendor says these two NexStars or comparable to the 12” dobsonian, but I’m not convinced. Any thoughts?
They're full of it. Having a 12" aperture over the others makes a significant difference (depending on what you're trying to observe, of course). The Dob is also capable of providing wider true fields of view. Of course, it has some disadvantages compared to the NexStars, as well, but they're not comparable optically. SCTs are *not* better than Newtonians per aperture. They were just trying to sell you something more expensive.
@@rbrtck thank you very mulch for your response. That’s how it felt like when I spoke with them. Thank you for confirming!
The focal ratio of your Dob is f/6, not f/5.
Thank you
Nice comparison
very helpful
Clean your glass....
Right? Drove me nuts mate I wanted to take a cloth to it myself.
@@midnitelitecompany You don't touch them things with a cloth.. You use a camera lens brush and blower. I seen people use a cloth and it had one speck of dirt on it. Instant scratches like sand paper was used...They had to send it off to polish it out.
@@WizzRacing how in the hell would you even get that thing cleaned?
@@upnorthoffcuts929 You take the front off. Unbolt it from the rear. Then take it out to clean it.. Unless you got some cheap scope..
In my country Chile a orion Dobsonian 8 inchs cost around usd 900... if the minimun salary is USD500 for 20 days of labor 10 hours at day...
I’m sorry to hear that. Seems out of reach to most people then 😕
On the upside, you guys have some of the best observatories in the world and they are sometimes open to the public, as I understand. I wish I could experience that.
06:00: That's not correct. Focal ratio (aka "speed") has nothing to do with how wide or narrow the view is, or consequently, how much it magnifies the target. This is determined by the focal _length._ The focal ratio is simply the focal length divided by the aperture.
What the focal ratio does, is determine how much light is being gathered in a given amount of time. Lower focal ratios gather more light in the same amount of time, the same amount of light in less time, or a combination thereof. If you double the diameter of your telescope, while keeping the focal length (magnification) the same, you gather 4 times as much light in the same amount of time. This will decrease the required exposure time for the same "quality" of photo, and will make fainter objects easier to see during visual observation. However, the area that fits in your view remains exactly the same.
The only time your statement holds true is when comparing telescopes with the same aperture. In those cases, a lower focal ratio will indeed indicate a wider field of view. But that's only because at the same aperture, a lower f-ratio is a consequence of a lower focal length. It's not the focal ratio that is responsible for the larger or smaller magnification; it's the focal length.
Take for example a 400mm focal length scope with a rather smallish 80mm (3.15") lens. This has a focal ratio of 5. However, so does a 2000mm telescope with a big, fat 400mm (15.75") lens. The 400mm scope will allow you to image larger nebulae though, whereas the 2000mm scope will be too narrow, but an excellent scope for planetary observation.
Lol ,you write so much and you still wrong
@@velkylev4217 Damn, your arguments are convincing. In light of the evidence you provided, I fear I have no other choice than to reconsider my statements.
But just for the retards who didn't quite catch what you're on about, could you perhaps explain it again in terms they could understand as well? I mean, after a thorough study of your counter arguments, I believe I could to it myself, but I'm sure you could explain it way better than me. Just repeat the arguments you presented above, but dumb them down for a general audience.
In conclusion, the sky watcher of 300 and motorized is better than the nextar 8se
Thank you.
Nope it is an f6
I hate it when things jew up.