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Having trouble picking which telescope to buy Help

cassegrain catadioptric Celestron Meade
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#1 voyager74656

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Posted 16 June 2019 - 12:07 PM

Hello i'm going to be buying a new telescope soon after picking the hobby again soon and for once i have more money to spend. i have already narrowed down that i want a Cassegrain telescope and i have several contenders that i have been considering but still not really getting anwhere with a choice. so my choices are the meade ETX 125 Observer or Celestron Nexstar 6 SLT now i know the difference between the two one being a Maksutov and the other a Schmitt and i want a kinda all rounder that will do decent plantary observing as well as letting me veiw some Deep sky objects and i have researched that the celestron schmitt with the larger aperture will be better than the longer focal range of the meade ETX so what i wanna ask is am i on the right track with my thinking?

 

Thank you



#2 Astroman007

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Posted 16 June 2019 - 12:17 PM

If those are the choices, I'd go with the Celestron.


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#3 Gary Z

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Posted 16 June 2019 - 12:31 PM

Save yourself a lot of frustration and get the Celestron Nexstar 6 SE.  I had an ETX 80 some years back and during the one year it was in warranty, had it replaced 4 times.  Now If I understand you correctly about your Celestron choice, it is the Nexstar 6 SE?  The SLT line that Celestron is ok, but mounts are considerably shaky.  The SE Mount is better and the 6 is actually better suited for the mount vs the 8 inch version.  I know currently Celestron is having a sale on their SE Mounts.  The 6 SE is going for $699.00.    Now, you can still get the SE Mount separately for about $499.00 Any 6 or 8 inch SCT with a vixen bar will work on this mount.  Now, both telescopes will be fine for planetary, but objects viewed through the Celestron will be brighter. 

 

I have also used a small refractor (AT72 ED) on the SE Mount and it does a good job with imaging the moon and some DSOs, but honestly for better stability, I'd go with the EVO Mount or an equatorial mount for DSO imaging.  Planetary imaging can be done nicely with a camera such as the ZWO ASI 224 and a 2x barlow.

 

If there is any more serious thought as far as DSO imaging is being considered, maybe a better suited mount such as an equatorial mount would be considered. 

 

Gary


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#4 SirLoyne

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Posted 16 June 2019 - 12:31 PM

I'm wildly inexperienced, as I've only had my scope for 1.5 years, so my thoughts should count for very little on this. I've got a 100% manual 8" dob. I like hunting down DSO's, so for me this sounds like something I would be extremely unhappy with. If you're only really interested in the Moon and planets, it fairs better. This isn't my review. It's just one I found online.

 

"5” of aperture plus a super long focal length and GoTo doesn't yield too much. Some bright planetary nebulae like the Blinking Planetary, Eskimo Nebula, and of course the Ring and Dumbbell nebulae are interesting, but that’s about it.

 

The Andromeda Galaxy would show a dust lane with a 5”, but the ETX-125’s super long focal length means you’re cramped at too high of a power to see it. Many of the Messier galaxies like M33, M74, M95, M96, and a few in Virgo are downright impossible to see due to the ETX’s f/15 focal ratio making them too diffuse and dim to shine against the background.

 

The ETX does pretty well on globular star clusters. It’ll show you most of the ones in the Messier catalog (except for some of the dimmer and more diffuse ones like M4 and M55), but none will be resolvable as anything but smudges except perhaps M3 and M13."

 

Meade ETX125 Observer Telescope Review

https://telescopicwa...lescope-review/


Edited by SirLoyne, 16 June 2019 - 02:44 PM.


#5 voyager74656

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Posted 16 June 2019 - 12:43 PM

Hello and thank you all for replying. I have been looking into Celestron Nexstar 6 SE but unfortunatly where i am in england its like £850 compared to the Nexstar 6 SLT which comes in at £650 so for my current budget i cant afford the SE and as for Dobs and newts i had a newt for my first scope and i could not get the hang of collimation so therfore lost interest so this time round i figured to try a telescope thats as high end as i can afford and with no messy collimation and hence my choices with the schmitt and Maks. I'm never gonna be much more than amatuer and i am doing this for me so i believe the celestron will be the one So thank you so very much i apreciate all your comments



#6 ShaulaB

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Posted 16 June 2019 - 01:03 PM

Occasionally, Schmidt-Cassegrain scopes need collimation. It is not that difficult to do. The secondary collimation screws are hidden underneath the circular plate that covers where the secondary mirror is located. I have personally done this with a C8 OTA, no problems. I hear some people who have SCT's say "I bought it because it will never need collimation." Sadly, this is not true.

 

A Maksutov is much more difficult to collimate. I bought a 4SE last year, and fortunately the optical alignment was in good order. When I went online out of curiosity about collimating a Maksutov, I got discouraged quickly.

 

You might want to think about buying a scope without a computerized mount. That will save lots of money. Regarding Dobsonians, if you can get a 6" f8, that would serve your needs well. At f8, the collimation should hold well over time. Faster Dobs (lower F ration) are the ones that need frequent collimation adjustments. At f8, you can achieve a high magnification for viewing planets. I have observed all 110 Messier objects with our 6" f8 Newtonian that had just a clock drive (RA tracking motor). The scope's mount has no computerized functions, as I used it in the 1980's and early 90's when normal people could not afford such luxuries.

 

If you get a mount with electronics, please know that these are battery hogs. A set of ordinary batteries will only last through three or four observing sessions. On the small computerized mounts which I use, there is no warning of "Low Battery." The mount will act oddly, then quit altogether with no warning when the batteries get low. This is really disconcerting, especially at an outreach event. So for our scopes that require power, we use special power supplies for the scopes. Beginners often ask what accessories to buy, and a Power Tank of some kind should be high up on the list.

 

Best of luck, and clear skies to you this summer!


Edited by ShaulaB, 16 June 2019 - 01:05 PM.


#7 Gary Z

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Posted 16 June 2019 - 01:12 PM

Hello and thank you all for replying. I have been looking into Celestron Nexstar 6 SE but unfortunatly where i am in england its like £850 compared to the Nexstar 6 SLT which comes in at £650 so for my current budget i cant afford the SE and as for Dobs and newts i had a newt for my first scope and i could not get the hang of collimation so therfore lost interest so this time round i figured to try a telescope thats as high end as i can afford and with no messy collimation and hence my choices with the schmitt and Maks. I'm never gonna be much more than amatuer and i am doing this for me so i believe the celestron will be the one So thank you so very much i apreciate all your comments

If you can, try to join as local to your location as possible, an astronomy club.  They can easily help you collimate.  Note the possibility of obtaining used Celestron might also be considered. The MAK won't need collimating, but the SCT will need it once in a while.  Everyone starts somewhere.  The MAK is a fine telescope (optically speaking only)  The ETX Mount, not so much.  I've seen some very impressive planetary images of the moon and planets taken with the MAK.  You can always mount a MAK on the SE mount.  They also do make a similar sized MAK for the Celestron SLT mounts, but, the SLT mount is rather shaky, but you could possibly find another tripod for the mount.  I have seen the SLT Mount slew around and it does it nicely. 

 

Take care,

 

Gary


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#8 scadvice

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Posted 16 June 2019 - 01:43 PM

As said above by Gary...join a local club. They, alot of times have loaners and other members are always happy to have you look through their instruments. THEN with that knowledge think about what you can afford to buy and what you will get for that investment. 


Edited by scadvice, 16 June 2019 - 01:44 PM.


#9 SeattleScott

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Posted 16 June 2019 - 01:51 PM

A Mak may be more difficult to collimate, depending on the model. But they hold collimation better than SCT. The Meade ETX Maks were intended to probably never need collimation. Assuming no abuse. I mean they are not designed for user collimation. So if you want something really maintenance free you might consider the Mak, but in general the SCT is more of an all rounder. Personally I would stay away from any post-2005 Celestron SCT unless you like disassembling the scope to clean the inside of the corrector every couple years. Kind of Celestron’s dirty little secret that everyone knows about but no one says anything because Celestron is generally held in higher regard than Meade in these forums. And the SLT is very entry level, but then I suspect the Meade Observer mount is also.

Scott

Edited by SeattleScott, 16 June 2019 - 01:55 PM.

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#10 sg6

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Posted 17 June 2019 - 03:10 PM

Where in the UK are you?

http://www.astronomyclubs.co.uk/

Search through your county and if near an edge the adjacent one(s) as well.

I think fedastro have a list but some years back they altered the order to Alphabetical, and a name like Black Hills AS was unidentifiable almost. I know at least 4 areas called Black Hills, the length and breadth of the UK. Friend lives at one of them.

 

I am a bit nervous of the scopes and the reasons, mainly the reasons. I have an ETX 105, nice scope but pain to align. Basically too narrow a field of view. They don't mention that however. Also the "field" is actually half of what you calculate. So mit gets worse.

 

Easy set up, although small:
Skywatcher AZ GTi and a 72mm ED Skywatcher.

Want to go "big", EQ5 goto and a 102mm (or maybe 127mm) Achro at around f/8. In a years time get that 72mm ED add a DSLR and capture images.

If you want people to get interested in the scope a Tal 100RS (used).

 

Problem is the lure of some big aperture and/or long focal length for high magnification tends to win out. Ease and simple get forgotten.



#11 gnowellsct

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Posted 17 June 2019 - 04:20 PM

Keep saving till the 6 se or 8 se is half your budget. It's wrong to jump into this hobby without reserves beyond what is needed for initial scope. Ask around and see if dew is a problem. You likely will need a dew heater and battery.

#12 Bowlerhat

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Posted 17 June 2019 - 06:20 PM

SCTs are not suitable with DSOs, but you're correct if you want to use it for planetary. The ETX mount is huge though, and I think the nexstar is better. This might be a reach but in nexstar IIRC they're compatible with fastar system as well.

 

However these two scopes are not cheap, and I wonder if you have thought about purchasing any accessories with it. Finderscopes, Eyepieces, you'll need to factor those in cost.



#13 Gary Riley

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Posted 17 June 2019 - 06:36 PM

With either a Mak or SCT you will need to figure in a dew shield. The front corrector glass are prone to dewing up fairly easily. You may have to figure in a dew heater strap and controller to help control dew even with a shield. Also you will need to think about an auxiliary power supply to power the go-to scopes. The batteries used in these mounts will not last very long. Good luck on your hunting.

#14 Charles Funk

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Posted 17 June 2019 - 07:01 PM

Of the two I'd definately go for the 6" SCT.

 

!! WARNING !!  Someone already mentioned this, you should know a SCT will require active dew control. The corrector plate is a dew magnet. Factor in another $250-300 (U.S.) to get accessorized. You will need a control box and 2 heater strips (if you gotta get in to active heating anyway, get a strip for the eyepiece), a portable jump start battery pack, as well as a dew shield to get setup proper. 

 

I was the noob who spent a good chunk of $$ on a new 8" SCT and found out the hard way that dew will fog you up and ruin your night, and darn quick to boot. I'm still a little ticked that manufacturers never mention the dew problem when writing up adverts to sell these scopes. Unless you live in a very dry region, dew will find your SCT. Trust me.

 

It has been correctly pointed out already that even SCT's require collimation, although infrequently. Thing is, if you want to enjoy astronomy, sooner or later you will have to butt heads with the collimation monster. It's really not so bad once you get the hang of it and it is nothing to fear. There are numerous sites on the net to help with understanding the process.

 

Just throwing this out there, a 6" dob doesn't need dew control, is light, very portable, quick to setup, and are usually coming in at F8 which is easy on collimation, and quite capable scopes. They are also pretty darn cheap. ;)


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#15 gnowellsct

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Posted 17 June 2019 - 10:20 PM

 

 

I was the noob who spent a good chunk of $$ on a new 8" SCT and found out the hard way that dew will fog you up and ruin your night, and darn quick to boot. I'm still a little ticked that manufacturers never mention the dew problem when writing up adverts to sell these scopes. Unless you live in a very dry region, dew will find your SCT. Trust me.

 

Yes, yes, and yes.  If he lives in the southwest or west coast, he could probably be fine without dew control.  --GN



#16 gnowellsct

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Posted 17 June 2019 - 10:21 PM

SCTs are not suitable with DSOs, but you're correct if you want to use it for planetary. The ETX mount is huge though, and I think the nexstar is better. This might be a reach but in nexstar IIRC they're compatible with fastar system as well.

 

 

Howzzat again?  Perhaps you mean wide field DSOs of > 1 degree?  There are zillions of DSOs that look terrific in SCTs.



#17 Bowlerhat

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Posted 17 June 2019 - 11:03 PM

Haha, I agree, but I still feel it's too narrow sometimes. Moreover, larger FOV is much easier to handle.

 

That's why I'd rather channel that cat power towards planets



#18 gnowellsct

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Posted 17 June 2019 - 11:09 PM

Haha, I agree, but I still feel it's too narrow sometimes. Moreover, larger FOV is much easier to handle.

 

That's why I'd rather channel that cat power towards planets

And so it is written:  that the path of the refractor bends towards the cat, and the path of the cat bends towards the refractor:

 

cff and c14 chimney mountain 2019.jpg

 

(But the C14 eats the 92mm alive for deep sky, and most deep sky is pretty narrow field)


Edited by gnowellsct, 17 June 2019 - 11:10 PM.

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