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Telescope Recommendation

ATM beginner equipment observing planet
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#1 newbuddy

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Posted 27 November 2020 - 05:55 AM

Hi Friends, I am a newbie in star gazing and was looking at buying a starter telescope. My expectation is mainly to observe planets (Jupiter band, Saturn rings, etc.) and also if possible a few deep space cosmos.

Based on my budget, I have short-listed the following:

 

1. Meade Telescope Infinity AC 70/700 AZ

2. Omegon Telescope AC 70/700 AZ-2

3. Skywatcher Mercury 707 70mm/700mm AZ-2

4. Celestron Telescope AC 70/900 Astromaster 70 AZ

5. Bresser Telescope AC 70/900 Sirius AZ-1

 

As far as I understand, (1) 70/900 would better suit my requirements (compared to 70/700), and (2) AZ mount is better than EQ for beginners.

 

I would really like to hear your suggestions and recommendations on which of the above would be the best to purchase in terms of optical clarity and viewing experience. Also, should I go for 2x Barlow or 3x Barlow lens?

Thanks a lot for you help!


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#2 phillip

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Posted 27 November 2020 - 06:32 AM

I actually started my Jr years with that size, mine had decent optics as a Swift refractor so many years ago.

 

They are fun, will see banding on Jupiter and it's 4 moon shuttle back and forth. Saturn nice but detailed division in ring a challenge that size of scope. 

 

Don't recall seeing much detail in deep sky, tho brighter ones detected. As need aperature to capture on these dimmer objects.

 

Will be a nice starter. But later if the hobby grabs your attention you will get into more decent size. 

 

My first real entry was a 6 inch reflector and never looked back. I love planes to this day, the setup will get your attention for sure ! 

 

Good Luck

 

Clear Sky

 

Xt8i, xt10, 6 inch advanced refractor great on planets ! 



#3 Sky Muse

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Posted 27 November 2020 - 06:53 AM

Hi Friends, I am a newbie in star gazing and was looking at buying a starter telescope. My expectation is mainly to observe planets (Jupiter band, Saturn rings, etc.) and also if possible a few deep space cosmos.

Based on my budget, I have short-listed the following:

 

1. Meade Telescope Infinity AC 70/700 AZ

2. Omegon Telescope AC 70/700 AZ-2

3. Skywatcher Mercury 707 70mm/700mm AZ-2

4. Celestron Telescope AC 70/900 Astromaster 70 AZ

5. Bresser Telescope AC 70/900 Sirius AZ-1

 

As far as I understand, (1) 70/900 would better suit my requirements (compared to 70/700), and (2) AZ mount is better than EQ for beginners.

 

I would really like to hear your suggestions and recommendations on which of the above would be the best to purchase in terms of optical clarity and viewing experience. Also, should I go for 2x Barlow or 3x Barlow lens?

Thanks a lot for you help!

I have the Celestron "AstroMaster" 70/900; the EQ variant.

 

A 70mm f/13 achromat plays very well with the general 4mm-to-40mm range of eyepieces.  But that particular refractor comes with an exclusive, proprietary focusser, and a nightmare, whether with an equatorial or alt-azimuth.  I'm still on a seemingly never-ending search for a suitable replacement for that focusser.  

 

The Meade "Infinity" 70/700, at f/10, would still exhibit minimal false-colour when viewing brighter objects; then, a 2x-barlow for the higher powers.  There's really no need to get a 3x, for a refractor, for if you insert the 2x into the refractor first, then the diagonal and eyepiece, that will make for an effective 3x-multiplier of the telescope's focal-length...

 

https://i.imgur.com/rcUATDy.jpg

 

You'll want a short barlow, the shortest you can find; for examples...

 

https://www.astrosho...ic-1-25-/p,2289

https://www.astrosho...x-1-25-/p,47673


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#4 MellonLake

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Posted 27 November 2020 - 07:07 AM

https://telescopicwa...copes-rankings/

They suggest the Meade Infinity 70mm which is probably the best bet.  

 

Our eyes require an exit pupil of ~0.5mm or larger.  With a 70mm telescope this means the maximum practical magnification is 140X but in reality is probably closer to 100X to 120X and more magnification probably will just dim the view and not show more detail (it will make the object appear very slightly larger).  The Meade comes with a 26mm and 9mm eyepiece and a Barlow  This will give 27X, 54X, 77X, and 154X.  While the 154X is a little much, it is probably ok.  This is a good magnification range for this telescope. 


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#5 Bean614

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Posted 27 November 2020 - 07:42 AM

Reality Check:  First, Jupiter & Saturn are VERY low in the sky right now, (If you're in North America---You SHOULD provide us with your Location to get real assistance) so you'll be looking at them through Thick Atmosphere, and won't see very much.  They'll both be gone soon, and won't return until late next Summer.  Mars is high, but getting smaller every day, and will be around again in 2 years.  Uranus & Neptune would be tiny dots in a 70mm scope.

  The things you would want to see in the "deep space cosmos" (referred to on this site as DSO's (Deep Space Objects) would be very small in a 70mm scope.

   If you REALLY wish to see what can be seen well for the next year, the recommendations for an 8" Dob are on the mark.



#6 Stellar1

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Posted 27 November 2020 - 07:48 AM

I’ll second the 8” dobsonian for any beginner, the planets are a challenge right now considering their position in the sky. An 8”dob will provide much nicer but (fleeting) planetary views right now and will provide much better deep sky views considering it’s much greater light grasp vs a 70mm. An 8” Dob will provide lots of fun for years to come. 



#7 rhetfield

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Posted 27 November 2020 - 08:16 AM

I would seriously consider saving up for a 130/650 reflector like the zhumell 130 or Awb Onesky/heritage 130. These sell for $200 in the US. I traded up from a 70mm reflector to one. It is a night and day difference that is well worth the price. You will see planetary detail and DSO's that simply are not possible in a 70mm.

In addition, think about ease of transport and setup and how you will find objects. Many DSO's are not naked eye. Dobs and mini dobs can have DIY degree circles added for almost free to find these things easy.
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#8 PNW

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Posted 27 November 2020 - 10:28 AM

Here comes the Dob Crew. Well, I'm a refractor guy. My Infinity 102 is a great 12 pound Grab N Go. It's strength is wide angle sky sweeping. Open clusters and double stars are pinpoints of light against an ink black sky. Be forewarned, planets will appear about the size of a pea on an outstretched arm. The moon will show rubble in the bottom of larger craters. Don't forget a moon filter. For a beginners first scope, I don't think it can be beat. Considering most telescopes are out of stock and back ordered our classified's or other used source. 


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#9 SeattleScott

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Posted 27 November 2020 - 10:46 AM

Those scopes will work for viewing boats on the water, the Moon, Pleiades Star cluster, and Jupiter/Saturn in about six months. From what I hear Meade Infinity is probably best.

Scott

#10 MellonLake

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Posted 27 November 2020 - 11:02 AM

I suspect the original poster is on a budget.  If the budget can be expanded, or the original poster is willing to purchase in the used market, then more aperture is generally desirable (like a 90mm or 102mm refractor or a 130mm Newtonian or 150mm Dobsonian). 

 

More aperture is generally desirable as it will allow for 1) higher resolution and 2) more light gathering power for deep sky objects (DSOs).  Aperture really helps with viewing many objects but nothing helps more with DSOs than dark skies.  Larger apertures also help with details on planets.  However, I would rather have my 90mm (3.5") telescope under dark skies than my 10" in heavy light pollution.   Yhe 10" under dark skies is always "wow".   The decision on more aperture is really a personal decision based on budget and what you plan to view.  Once you get past about 5", refractors become very expensive, Newtonian reflectors are relatively inexpensive (especially Dobsonians) for apertures from 4" up to 12".  If I were always viewing from my highly light polluted backyard, I might want to use a relatively small refractor as my primary telescope, fast light weight and easy to set up (the larger aperture will still do more and for planetary viewing from my backyard I still use the 10" most of the time).   With access to dark skies, I would always want the maximum aperture I could afford and move (I am not personally satisfied at 10"). 

 

Having said all of the above if a 70mm is all that your budget allows for the Meade Infinity 70AZ is a good choice.  If you decide to stick with the hobby then you can save up for a telescope with more aperture.  Most people who stick with this hobby have several telescopes (see all our signature lines).  There is no, one telescope does everything well.    

 

The most important thing is to get out under the stars and start using a telescope.  If that means getting the 70AZ now and saving for a better telescope, go for the 70AZ.    

 

All the best


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#11 seasparky89

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Posted 27 November 2020 - 11:06 AM

IMHO, if you want to keep your interest alive, may want to go bigger.  A 6” dob will allow great views of planets and several deep space objects.  It is very easy to set up and use, and it is a complete system right out of the box.  That coupled with a few star charts and a phone app such as Sky Safari would suit your needs nicely.


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#12 newbuddy

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Posted 27 November 2020 - 11:19 AM

Dear Friends,

 

Thank you very very much for the support and the detailed explanations. Accumulating all your suggestions, I think the choice in front of me is simple:

 

1. Cheap and easy: Meade Telescope Infinity AC 70/700 AZ

2. Better experience: Meade Dobsonian N 130/650 LightBridge Mini 130

 

I was also considering Omegon Dobsonian Advanced N 152/1200 (albeit bulky and a little more expensive but probably with better views).

Does these choices make more sense?

 

Thanks.


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#13 SeattleScott

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Posted 27 November 2020 - 11:23 AM

Many people test the waters with a cheap 70mm to gauge interest before spending real money. Unfortunately between the limited aperture and poor mechanics, these usually disappoint and interest usually doesn’t develop, even when there is legitimate interest. Personally my folks bought me a 60mm refractor as a kid. All it did was convince me backyard telescopes couldn’t show anything. A buddy with a real telescope finally convinced me otherwise in my 20’s. So buying these $100 refractors is usually a self fulfilling prophesy. Sure enough, I knew they wouldn’t be interested. Glad I didn’t waste $1,000. Now let’s see if we can get $30 for it on Clist.

On the other hand, I remember one gentleman come out with me and be impressed with what he saw. He promptly spent $1,000-1,500 on a new telescope and proceeded to barely use it. So yeah it’s tough. I get parents don’t want to spend a fortune before they know if the kid is really interested and will stay interested for more than 90 days. But buying a $100 scope that is only useful for a couple targets is likely to guarantee they won’t stay interested. There can be a middle ground where you get something that has significant capabilities for well under $1,000 in order to truly gauge interest without spending a fortune.

I mean, if your kid said they were interested in mountain biking, would you buy them a tricycle? I suppose you would if you wanted to make sure they wouldn’t develop an interest in mountain biking.

Scott
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#14 MaknMe

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Posted 27 November 2020 - 11:39 AM

I love viewing planets and splitting double stars in my 5 in Mak (Meade NG 125). It is light and easy to set up and the GOTO helps me learn the sky.

I bought my telescope in May and have already used it over 100 times this year. At under $400, I think it is the perfect beginners scope.

#15 MellonLake

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Posted 27 November 2020 - 12:02 PM

If you want to go the Dobsonian route the Omegon Dobsonian Advanced N 152/1200 is a better choice (if you ask me).  While it is a little bigger it will still be fast and easy to set up.  The longer focal ratio (F/8) will make it much easier to collimate than the Lighbridge mini (F/5).  The full size Omegon Dobsonain also does not require a table to view from which is nice if you are going to a dark sky site and you will not be subject to vibrations based on how stable the table is.   The Omegon also has a 2" Crayford style focuser which takes 2" eyepieces (which allows for expansive wide field views) and also Crayford focusers are generally easier to achieve good focus with.  The 152mm aperture is also into the range of working better on the fainter DSOs (8" or 10" is even better for Nebulae and Galaxies).  However, either are an ideal first telescope.  

 

The ability to view faint DSOs goes up with the square of the aperture.  A 150mm reflector telescope is (more or less) 4 times the light gathering power of a 70mm refractor (Doubling the effective aperture quadruples the light gathering power).  A 10" Dob is 2.8 times the light gathering power of the 150mm and about 11X the light gathering power of the 70mm.  However, DSO viewing is really best from Dark Skies.  The difference is less noticeable in heavy light pollution.  The difference between 130mm or 150mm and 250mm (10") under dark skies is remarkable in light pollution the difference (in my opinion) is less but still significant.    

 

Again there is no perfect scope.  Bigger telescopes will generally show you fainter objects (especially in dark skies) and more detail but they are heavier and cost more. The telescope for you is the one you will actually use.  Generally 6" to 10" Dobs are the best value vs. performance vs. usability in my opinion.    


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#16 LuxTerra

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Posted 27 November 2020 - 01:01 PM

I'm going to go a bit different route here and focus on education and expectation management. The Meade or Celestron are probably the two best on your list, just based on their volumes. Mass production allows for slightly higher quality for a given cost. There're all very similar budget optics, so stressing about which is "best" isn't super useful. Unless you're familiar with optics, it's unlikely you'll notice any practical difference between a slew of 70mm variants. Considering if you should buy a different style or altering your budget based on your expectations, is worth discussing.

 

One of the best things you can do is refine your requirements and exceptions before buying a scope. Typically, you could do this by going out with a club or star party, but COVID. I used a 85mm spotting scope for several years before buying my first "real" telescope, an 8" SCT. You can see a lot of interesting things with just a reasonable pair of binoculars. If you have anything to view the stars with, I recommend you grab what you have (maybe buy a cheap star chart to guide you) and just go to get an understanding and manage expectations.

 

I personally found the book "Turn Left at Orion" to be very useful for setting expectations on deep sky objects. There are illustrations of what you're likely to see, at a dark site, in a small refractor and a 10" Dobsonian. This not only helps you determine if a small refractor is going to be enough for your first scope on deep sky objects, but also teaches you what to look for. Visual observing is a skill.

 

I used my 85mm spotting scope at 20-60x magnification to observe mostly solar system objects (sun, moon, and planets) with good results. Picking up Saturns Cassini division is relatively easy, same with the Jupiters moons, bands, and red spot. However, that was a rather nice Zeiss optic; for its size, it performs extremely well on solar, but marginal on deep sky simply because of all my light pollution. I really needed a larger scope and proper light pollution filters to visually appreciate the deep sky objects...or drive 4+ hours to a true dark site. Light pollution is a problem and the filters really can't do much against the wide-band LEDs, but can work wonders on other narrow band emissions. Spend some time understanding your particular observing site challenges (unless you have a very dark sky).

 

As others have alluded too, there are some generalized rules to help guide you. Expectation management is critical IMHO. My thoughts:

  • Solar system objects will typically look better, more color contrast, in a refractor (lens design) than a reflector (mirror design) due to the central obstruction in a reflector (secondary mirror).
  • Deep sky objects will look better per dollar in most reflectors since you can get a much larger scope. Aperture is extremely important for deep sky; faint fuzzies. Light gathering power goes up by area. i.e. scales as a square of the radius. Thus, a 8-10" reflector scope is gathering significantly more light than a 3" refractor, but there are trades to be made. Deep sky objects won't have color because your eye is just not sensitive enough.
  • Refractors are mostly setup and go systems. Reflectors can require more maintenance such as collimation. Be honest in how much you want to tune/fiddle with your system. A badly collimated reflector will look terrible no matter how much light its gathering! Refractors are usually recommended for beginners for exactly this reason, but YMMV depending on your technical background. However, per dollar, you can see much better faint fuzzies with a reflector, but there are tradeoffs.
  • The atmosphere will practically limit your magnification to ~200x visually. The devils in the details here, but it's not a bad first order approximation. Typically, this means an 8-10" has all the resolving power you can typically use visually. Now obviously, larger telescopes exist for a reason and there are exceptions to the rule, but those details really aren't important for you right now, except for edification if you desire.
  • Related to the previous bullet, you don't really need more than a few eyepieces. Three or four is typically plenty. You'll typically choose the highest magnification that fits (FOV) the object of interest. I found the Televue guides useful (don't have to buy their equipment as it's rather pricy, just use the info). E.g. for an 8" SCT, they recommended a 31mm, 17mm, and 10mm. I have those plus a 6mm for those rare times the atmosphere allow more magnification.
  • Consider your environmental conditions and observing sites (check out dark sky maps). Here on the East coast USA, it's so humid typically I simply cannot observe for more than an hour without dew heaters on the 8" SCT. First time I used that scope, there was dew dripping off it after 45mins! The smaller refractor was manageable without dew heaters as long as I managed it. Please consider the support equipment you'll need, since it can add up quick. Also, things can get complicated fast. For example, I needed an OTA and eyepiece dew heaters, a controller and now a large battery to power it all. Lots more cables and longer setup. 
  • Consider the overhead in transporting the system to an observing site, whether that's your backyard or by car to somewhere else. Be realistic in how much time it will take to prepare, pack, travel, unpack, observe and return.
  • Consider GoTo automation; it's a blessing and curse. Personally, I went with a Celestron StarSense setup because I really just wanted the computers to do their thing and let me drive by object. This is extremely different cost/experience than manual approaches. Both have pros/cons.
  • Unless you really think you might take an interest in a photography, just get an Az/El mount if you go computerized. Setup is far easier not bothering with polar alignment.

So, at these class of optics, I wouldn't expect to see much but the brightest deep sky objects, but you can see the solar system objects reasonably well. However, as noted, the planets are not great at the moment and will quickly be gone until next year depending on your location. Plus, it's getting cold. If this is your budget, just realize the limitations and decide if it's worth the money or not. If you really want to see deep sky objects, you'll need to go someplace rather dark and/or get a larger scope. All of which will cost more money. With this class of optics you won't see anything like the pictures on the box.


Edited by LuxTerra, 27 November 2020 - 01:03 PM.

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#17 newbuddy

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Posted 27 November 2020 - 04:34 PM

Dear Friends,

 

Thanks again for the insights shared. It has really helped me with narrowing my choice here. Now, it is between the following two:

(1) Celestron AC 90/1000 Astromaster AZ

(2) Omegon Dobson Advanced N 152/1200

 

The concern now is the bulkiness between the two - how difficult would it be to transport the Dobson (it seems to be heavy) and the setup with fine-tuning the collimator - please take into consideration that I am a complete newbie. Also, the difference in viewing might not be that might, right?

 

Thanks.


Edited by newbuddy, 27 November 2020 - 04:37 PM.


#18 MellonLake

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Posted 27 November 2020 - 04:50 PM

I started with a 10" Dob as a newbie the 152mm Dob will be even easier. 

 

The 152mm Dob is easy to carry and super set up.  It is really not at all heavy.  The set up time is faster for the Dob than the refractor because you don't have a tripod to set up.  Also, collimation on an 6" f/8 telescope is not that critical and easy to do, the cheap laser collimators are good enough and it takes less than a minute to collimate with the cheap laser.  Most times you probably won't even have to change the collimation. 

 

I would also take the 152mm Dob over the 90/1000 because the Dob will have no chromatic aberration and will provide sharper views of planets.   The 152mm will significantly outperform the 90/100mm Celestron in all observing.  The Dob will be way better on DSOs and considerably better on planets and lunar.   

 

In my opinion there is no comparison, I would take the 152mm Dob without question.    


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#19 spaceoddity

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Posted 27 November 2020 - 11:02 PM

Dear Friends,

 

Thanks again for the insights shared. It has really helped me with narrowing my choice here. Now, it is between the following two:

(1) Celestron AC 90/1000 Astromaster AZ

(2) Omegon Dobson Advanced N 152/1200

 

The concern now is the bulkiness between the two - how difficult would it be to transport the Dobson (it seems to be heavy) and the setup with fine-tuning the collimator - please take into consideration that I am a complete newbie. Also, the difference in viewing might not be that might, right?

 

Thanks.

It depends on your method of transport. The 6" dob isn't real heavy and the tube will fit across the backseat of even a small car while the base would easily fit in the passenger seat. If you don't own a vehicle or have passengers, then yes it would be difficult to transport. You can also lay the base sideways on top of the tube so long as you have the tube protected with a heavy blanket of something similar. I've done that with my XT10 when I had a passenger. I'd go with the dob myself. 152mm is still a significant increase in aperture over 90mm that will be easily noticeable. 



#20 Sky Muse

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Posted 27 November 2020 - 11:10 PM

Dear Friends,

 

Thanks again for the insights shared. It has really helped me with narrowing my choice here. Now, it is between the following two:

(1) Celestron AC 90/1000 Astromaster AZ

(2) Omegon Dobson Advanced N 152/1200

 

The concern now is the bulkiness between the two - how difficult would it be to transport the Dobson (it seems to be heavy) and the setup with fine-tuning the collimator - please take into consideration that I am a complete newbie. Also, the difference in viewing might not be that might, right?

 

Thanks.

The Celestron "AstroMaster" 90mm has the same oddball focusser as the 70mm, but larger.  It'll do okay at the lower powers, but as you go up in power the views may worsen, and not due to the atmosphere.  In addition, that design and execution of an alt-azimuth isn't the best, and may be the worst on the market.  If it's down to those two, go with the Omegon Newtonian-Dobson.  The Omegon 152mm will be much more revealing whilst observing, over the 90mm; much brighter, more detail, but you will need to collimate the Newtonian on occasion, possibly when it arrives, and a tune-up once in a while thereafter.

 

Of course the "Dobsonian" will be heavier, but that's the price to pay for a telescope with a larger aperture.  Besides, a 6" f/8 "Dobsonian is not that large and heavy.  But then, you may find the extra effort in handling and storing worth the improved views, or not.  Time would tell.



#21 KBHornblower

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Posted 28 November 2020 - 12:14 AM

snip...

 

As others have alluded too, there are some generalized rules to help guide you. Expectation management is critical IMHO. My thoughts:

  • Solar system objects will typically look better, more color contrast, in a refractor (lens design) than a reflector (mirror design) due to the central obstruction in a reflector (secondary mirror).
  •  
  • ...snip

Some of us appear to be making the central obstruction in a reflector much more of a bogeyman than it really is.  Assuming perfect figuring, a 6" reflector with a 2" obstruction will deliver virtually the same contrast across the face of a planet as a 4" refractor, at lower cost, according to experts who know how to calculate the diffraction-related transfer function.  I see no reason why any color contrast between different parts of the planet would be suppressed in the reflector.  If the refractor appears to show more color, I would suspect chromatic aberration.  The commonly seen superiority of the refractor under real world conditions is primarily due to less sensitivity to thermal and collimation problems.  In addition, off-axis coma can be virtually eliminated from a refractor objective.


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#22 LuxTerra

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Posted 29 November 2020 - 09:34 AM

Some of us appear to be making the central obstruction in a reflector much more of a bogeyman than it really is.  Assuming perfect figuring, a 6" reflector with a 2" obstruction will deliver virtually the same contrast across the face of a planet as a 4" refractor, at lower cost, according to experts who know how to calculate the diffraction-related transfer function.  I see no reason why any color contrast between different parts of the planet would be suppressed in the reflector.  If the refractor appears to show more color, I would suspect chromatic aberration.  The commonly seen superiority of the refractor under real world conditions is primarily due to less sensitivity to thermal and collimation problems.  In addition, off-axis coma can be virtually eliminated from a refractor objective.

Wasn't going to go into the details as its not really the point, but since it has been raised, I'll address it only briefly as it's a bit of a tangent. This has been discussed, modeled, simulated, and tested extensively. You can find a quick summary here: http://www.astrophot...bstruction.html Truly understanding all of this requires Fourier analysis, etc. If you ever had to take a linear systems and signals class or similar as a mathematics or engineering major, that's not a big deal, but its a level of math most people prefer to avoid.

 

The OP had no reflectors to compare the original refractors against. The 6" Dob now in the running, is considerably more expensive than the original refractor. Chromatic aberrations of these refractors is a given since they are not color dispersion corrected like an APO (which is more like 10x the cost give or take).

 

All that said, the 6" Dob will easily outclass the refractors in all respects, color, resolution, brightness.



#23 LuxTerra

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Posted 29 November 2020 - 09:48 AM

Dear Friends,

 

Thanks again for the insights shared. It has really helped me with narrowing my choice here. Now, it is between the following two:

(1) Celestron AC 90/1000 Astromaster AZ

(2) Omegon Dobson Advanced N 152/1200

 

The concern now is the bulkiness between the two - how difficult would it be to transport the Dobson (it seems to be heavy) and the setup with fine-tuning the collimator - please take into consideration that I am a complete newbie. Also, the difference in viewing might not be that might, right?

 

Thanks.

The 6" Dob will easily outclass the small refractors you originally listed and is well worth the cost increase. The dob will collect about 4.5x more light and thus, be capable of many more deep space objects than the 70mm refractors. Also, you should be able resolve more details on the planets. The Dob will be easier to set up and should, although I have no direct experience with this specific Dob, be more stable than the tripod refractor. All around, it's a better option.

 

The Dob is a good entry level optic The original refractors are closer to a toy than a good entry optic. They're just too limited.



#24 LDW47

LDW47

    Fly Me to the Moon

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Posted 29 November 2020 - 10:42 AM

Hi Friends, I am a newbie in star gazing and was looking at buying a starter telescope. My expectation is mainly to observe planets (Jupiter band, Saturn rings, etc.) and also if possible a few deep space cosmos.

Based on my budget, I have short-listed the following:

 

1. Meade Telescope Infinity AC 70/700 AZ

2. Omegon Telescope AC 70/700 AZ-2

3. Skywatcher Mercury 707 70mm/700mm AZ-2

4. Celestron Telescope AC 70/900 Astromaster 70 AZ

5. Bresser Telescope AC 70/900 Sirius AZ-1

 

As far as I understand, (1) 70/900 would better suit my requirements (compared to 70/700), and (2) AZ mount is better than EQ for beginners.

 

I would really like to hear your suggestions and recommendations on which of the above would be the best to purchase in terms of optical clarity and viewing experience. Also, should I go for 2x Barlow or 3x Barlow lens?

Thanks a lot for you help!

Whatever scope you get make sure its on a decent AZ mount not an EQ mount, as a first timer you won’t regret it ! Good Luck and clear skize ahead !



#25 vtornado

vtornado

    Gemini

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  • Loc: Northern Illinois

Posted 29 November 2020 - 03:31 PM

Hi, Aperture really helps all targets.   Can you go to an 80mm f/11? 

It is probably not much more money.

30% more light gathering.

CA is well controlled.

Can still fit on a light duty mount.

 

If you do go with the 70mm scope, I would not exceed any combination of barlows that go over 140x.    For my Chinese budget refractors,

Even though theory says you can go 2 times the objective diameter.  I don't find that to be true.  1.5x is more like it.   So for that you are at

roughly 110x. 

 

The 900mm scopes slightly favor the moon, and planets over the 700mm ones, but the 700 can have a wider field of view,

which is important to help you find items.  Both the 700mm and 900mm will have acceptable levels of CA for planetary viewing.

 

Due to the priciple of leverage, the 700mm scopes will be steadier than the 900 on the same mount.  Do not underestimate

stability.  fighting with a scope that wants to constantly slip for where you move it is fustrating.

 

I see most of these scopes are yoke mounts with a supporting rod.   I had a 60mm f/13 telescope like this and I did not like the mount

It was hard to find a sweet spot where the scope could be moved and a place where it would stay where you put it.

 

I do not have this mount, so I cannot judge its stability, but it does have slow motion controls, which are VERY helpful

in tracking moon and planets.

https://optcorp.com/...cting-telescope


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