Views on non collimateble Newtonians?

[Spier24]

What are your views on Skywatchers range of newts that are non collimateble and supposedly don't require collimation? I know they have it on a few scopes now. A 150, 130 and some smaller scopes. What's everyone's experience with any of those scopes if you've owned them? Or your reasons for not buying one.

[Ricochet]

I wouldn't worry about the primaries being "non-collimatable". A telescope only requires regular collimation if things flex and move so that the collimation is thrown off. The (plastic) mirror cells should be pretty resistant to such movement and so recollimation shouldn't be needed once set. However, if collimation out of the factory is not good then collimating the telescope on arrival is more difficult than with a traditional cell with adjustment knobs/screws.

The biggest consideration that I would have is that generally these telescopes have had the non-collimatable cell fitted as a weight saving measure. As a result they will also have small plastic focusers that will probably want shimming in order to tighten them up and prevent/reduce the draw tube flop. I believe TS sell a replacement focuser that can be fitted to such models should you find it necessary in the future. 

[Muc]

My only active scope at the moment is the 4" Astroscan which is not collimatable (well with any ease). The widefield views are great, really opens up star hopping. Have seen lots of firsts with it. Trying to push it at around 100x for double stars shows it's limitations. But I love it

 

[Stu1smartcookie]

Watch the article on the Astronomy and Nature channel on YouTube where he waxes lyrical about the 150p . As he rightly points out , skywatcher has a decent history of scopes and just because something isn’t “the norm” doesn’t make it inferior . In my mind anything that gets more people into this hobby  is a good thing .. and although collimation is a good “skill” to learn it often puts people off . I was discussing with another SGL member on Friday how much snobbery there is in astronomy. That’s almost understandable as traditional hobbies like ours generally  demand an understanding of the complexities involved in a scope or a mount . But , scope manufacturers are constantly trying to find new ways to produce a customer friendly product , and indeed to introduce low maintenance scopes . I think it’s a good thing . After all , who would have thought you would be using a smartphone to control your scope only a few years ago . I think the more people progress in this hobby  the more they want to learn . And the more they learn the more keen they are to learn about things like collimating a scope . There is definitely a market out there for these scopes . I’m just waiting for a maksutov Cassegrain  that never dews up without the need of a ridiculous dew shield .now there is an idea ! 

Edited February 7, 2021 by Stu1smartcookie

[wookie1965]

I had a 150p as my first scope brilliant collimating it the first time was a nightmare but its like riding a bike once done it's easy, I had to tweak that every time I took it out only the Primary though.

 

[John]

My first proper scope had a similar design. It was a 6 inch F/6 newtonian made by Astro Systems of Bedfordshire, UK back in the 1980's. The secondary was adjustable but the primary was fixed. These scopes were all metal though and carefully machined to maintain what was termed "refractor-like optical alignment" in the brochure. It worked rather well as I recall 

So if the scope is manufactured and assembled with some accuracy and care, it is a viable approach. This was my Astro Systems scope:

[ScouseSpaceCadet]

I've owned both the 130PS and the Star Discovery 150i (and vanilla collimatable reflectors). They are both nice little telescopes. When I sold the 130PS, the primary collimation was no different to when I bought it and the recipient was cock a hoop with his bargain.

Similarly, the 150i ota I own has brought me plenty of joy. It saw action on every clear night around Mars opposition. Having it track the red planet on an AZGTI resulted in a relaxed observation experience and added to the memorable views.

They're great introductory telescopes and also handy if you require something lighter than the standard fare.

Sky at Night Magazine has also recently printed a very favourable review of the Star Discovery 150i.

These telescopes have been around for several years and despite looking for it, I've yet to read any complaints from actual users about the lack of primary collimation. 

The only issue people have is usually with the somewhat flimsy focusers. Obviously designed to keep weight and costs down. This echoed my own feelings. Hence I fitted a rather nice TS-Optics crayford focuser to the 150i after reading a couple of other members some years back did the same.

Edited February 8, 2021 by ScouseSpaceCadet

[Spier24]

22 hours ago, Stu1smartcookie said:

Watch the article on the Astronomy and Nature channel on YouTube where he waxes lyrical about the 150p . As he rightly points out , skywatcher has a decent history of scopes and just because something isn’t “the norm” doesn’t make it inferior . In my mind anything that gets more people into this hobby  is a good thing .. and although collimation is a good “skill” to learn it often puts people off . I was discussing with another SGL member on Friday how much snobbery there is in astronomy. That’s almost understandable as traditional hobbies like ours generally  demand an understanding of the complexities involved in a scope or a mount . But , scope manufacturers are constantly trying to find new ways to produce a customer friendly product , and indeed to introduce low maintenance scopes . I think it’s a good thing . After all , who would have thought you would be using a smartphone to control your scope only a few years ago . I think the more people progress in this hobby  the more they want to learn . And the more they learn the more keen they are to learn about things like collimating a scope . There is definitely a market out there for these scopes . I’m just waiting for a maksutov Cassegrain  that never dews up without the need of a ridiculous dew shield .now there is an idea ! 

Very well put, I'm still deciding on what scope to get and collimation is being a pretty influential factor in that as I'm always swinging back and forth on which scope to get based on which scopes require collimation. The community seems quite friendly but I can see what you mean about the snobbery, the most common things I see from that is people getting scoffed at for wanting or owning a GoTo scope. Personally I think GoTo scopes are a god send in light polluted areas as star hoping isn't easy there, especially for a beginner. I live in a Bortle 7 area and have never owned a telescope before so a GoTo is a must for me.

[Spier24]

20 hours ago, ScouseSpaceCadet said:

I've owned both the 130PS and the Star Discovery 150i (and vanilla collimatable reflectors). They are both nice little telescopes. When I sold the 130PS, the primary collimation was no different to when I bought it and the recipient was cock a hoop with his bargain.

Similarly, the 150i ota I own has brought me plenty of joy. It saw action on every clear night around Mars opposition. Having it track the red planet on an AZGTI resulted in a relaxed observation experience and added to the memorable views.

They're great introductory telescopes and also handy if you require something lighter than the standard fare.

Sky at Night Magazine has also recently printed a very favourable review of the Star Discovery 150i.

These telescopes have been around for several years and despite looking for it, I've yet to read any complaints from actual users about the lack of primary collimation. 

The only issue people have is usually with the somewhat flimsy focusers. Obviously designed to keep weight and costs down. This echoed my own feelings. Hence I fitted a rather nice TS-Optics crayford focuser to the 150i after reading a couple of other members some years back did the same.

I've also seen very encouraging reviews about the scopes. The one thing that worries me is if the scope did go out of collimation. I imagine it would be harder to collimate than a scope that is designed to be collimated. 

 

There's a saying that says if you build something that's impossible to break then it'll be impossible to fix when it does break 😂

[John]

I think the secondary mirror does have collimation adjustment with these. It is the primary that is fixed.

 

[Louis D]

44 minutes ago, Spier24 said:

The community seems quite friendly but I can see what you mean about the snobbery, the most common things I see from that is people getting scoffed at for wanting or owning a GoTo scope. Personally I think GoTo scopes are a god send in light polluted areas as star hoping isn't easy there, especially for a beginner. I live in a Bortle 7 area and have never owned a telescope before so a GoTo is a must for me.

There are other options such as DSCs and even manual setting circles for finding objects in bright skies.

Gotos are fine once they're aligned, but too many beginners are put off by the difficulty of some (older) systems.  There are newer ones that align themselves using plate solving, which is terrific for beginners.  The problem is, how to get a newbie into a decent sized telescope with plate solving goto for under $200 to $300 (the typical beginner budget).  It's a different discussion when their budget is $2000.

[Spier24]

7 minutes ago, Louis D said:

There are other options such as DSCs and even manual setting circles for finding objects in bright skies.

Gotos are fine once they're aligned, but too many beginners are put off by the difficulty of some (older) systems.  There are newer ones that align themselves using plate solving, which is terrific for beginners.  The problem is, how to get a newbie into a decent sized telescope with plate solving goto for under $200 to $300 (the typical beginner budget).  It's a different discussion when their budget is $2000.

The Celestron sky align system is pretty full proof. I know that the deal-breaker for quite a few people when it comes to choosing between a skywatcher and celestron scope is that the celestron alignment system is easier to use. You don't even need to use a star for it.

[Spier24]

23 minutes ago, John said:

I think the secondary mirror does have collimation adjustment with these. It is the primary that is fixed.

 

Yes that's right 

[Jasonb]

I have one of these, the Skywatcher StarQuest 130P. When researching it I was wary of the primary mirror not being collimatable, but read a few reviews saying that it wasn't an issue at all, and decided to trust those reviews.

When it comes down to it, it's a good scope, but it is a budget one, and there are going to be some 'shortfalls' because of that. As already said, the focuser is cheap, and I have added some Teflon tape to reduce the give on the focuser tube. 

I have struggled with collimation of this scope; as people have said the secondary is collimatable. I think my struggles have been down to just lack of experience and also things like the give in the focuser tube, which means that there is a variance in the view through the cheshire. To be honest, having the primary collimatable as well would probably introduce yet another variable. At least I can trust that the primary is ok, and focus on the secondary (pardon the pun!).

[ScouseSpaceCadet]

2 hours ago, Spier24 said:

I've also seen very encouraging reviews about the scopes. The one thing that worries me is if the scope did go out of collimation. I imagine it would be harder to collimate than a scope that is designed to be collimated. 

 

There's a saying that says if you build something that's impossible to break then it'll be impossible to fix when it does break 😂

As mentioned previously, the secondary is collimated using the same method as the higher end scopes.

The primary is well fixed in place. I wouldn't want to experiment, but I imagine it would require quite a bump to shift the mirror.

If the unfortunate does happen, it is possible to remove the whole mirror cell and even re-collimate the primary using the three external cell fixing screws. At least one member here has dropped theirs from a height and used this method.

Edited February 8, 2021 by ScouseSpaceCadet

[Stu1smartcookie]

13 hours ago, Spier24 said:

Very well put, I'm still deciding on what scope to get and collimation is being a pretty influential factor in that as I'm always swinging back and forth on which scope to get based on which scopes require collimation. The community seems quite friendly but I can see what you mean about the snobbery, the most common things I see from that is people getting scoffed at for wanting or owning a GoTo scope. Personally I think GoTo scopes are a god send in light polluted areas as star hoping isn't easy there, especially for a beginner. I live in a Bortle 7 area and have never owned a telescope before so a GoTo is a must for me.

Goto Scopes are used right across the board these days ... look at people that image ..as long as polar alignment is achieved its a god send to find their target .. did i say polar align?... now there's another subject entirely  

And the visual only gang ... well , its a fast option ( i like computers and its cool to see a mount swing into action )  . Its also useful to learn the night sky though . There is a certain amount of pride in actually finding a target without the use of electronics . 

[cwis]

On 08/02/2021 at 23:04, ScouseSpaceCadet said:

As mentioned previously, the secondary is collimated using the same method as the higher end scopes.

The primary is well fixed in place. I wouldn't want to experiment, but I imagine it would require quite a bump to shift the mirror.

If the unfortunate does happen, it is possible to remove the whole mirror cell and even re-collimate the primary using the three external cell fixing screws. At least one member here has dropped theirs from a height and used this method.

Not sure whether I'm the member you are referring to here? My 130PS was supplied with the primary uncollimated (but no damage visible). We surmised it may have been dropped in transit or was perhaps uncollimatable from the factory and had slipped by quality control.

After help and advice from you lot I sent it back to FLO and they returned it perfectly collimated - they had enlarged the mounting holes for the plastic lens cell to allow enough adjustment (which makes me think it was a one off uncollimatable 'scope from the factory). 

It has stayed perfectly in collimation since but the whole process gave me the confidence to improve and upgrade it, so I replaced the primary mirror cell with a collimatable one from a  130P.  Focusser is next.

It does make me wonder however how many people actually properly check collimation - I posted yesterday about my Bresser Messier 10inch dob because as supplied as far as I am concerned the secondary mirror cannot be put central to the focusser with the secondary tilt 30mm thumbscrews supplied - they are too short as the spider was designed with 30mm recessed screws in mind. 

So either everyone with a Dob-254 with thumbscrew secondary adjusters owns an uncollimated telescope, or I'm particularly unlucky and have been supplied with one with the wrong length thumbscrews and therefore the second uncollimatable telescope in a row.

I'd say the odds are that I'm not the only person affected but the majority neither know nor care about accurate collimation as long as the views look OK and the laser spot lands in the middle of the doughnut.

 

[ScouseSpaceCadet]

@cwis no mate it wasn't you, however despite your initial woes, the crucial bit is, "It has stayed perfectly in collimation since...". 

I hope your luck improves. 🤞

The member I was referring to was Nigel G in this thread.

[cwis]

4 minutes ago, ScouseSpaceCadet said:

@cwis no mate it wasn't you, however despite your initial woes, the crucial bit is, "It has stayed perfectly in collimation since...". 

I hope your luck improves. 🤞

The member I was referring to was Nigel G in this thread.

I see! Yup - it didn't shift until I took it apart again.

Would I buy the same scope again? Yes.  It and the Az-gti are a stunning combo for a beginner.

But I'd check its collimation the day it arrived. It ended up showing me some amazing views of Mars when it came back from FLO.

I do seem to be having a bit of a run of luck though - first the 130ps, then a collimation cap with a non central hole, then a laser that was itself uncollimated and then the Bresser.

Luck seems to be getting better (touch wood) I even used the Bresser last night!  Star collimation was bang on and medium mags (150ish) were stunningly sharp even though it was a bit windy high up so happy days.

[ScouseSpaceCadet]

Yes my first was a 130PS and part of me wishes I'd kept it.

A collimation cap with no hole is hilarious. I'm glad it's unlikely we will ever fly on the same plane! 😆

[Carbon Brush]

My first proper scope was an Orion Optics 8" F4 newt. Ordered in 2003.
Thanks to their poor construction methods, poor quality control and poor packing for shipping I learned about collimation, starting at the deep end.
If I look down the tube from a distance should I see my face? Yes that is how far off the primary was!
At the end of the day (well a lot more than a day to deal with all the built in problems) I had an optically very good scope.
The 'wisdom' at that time was that I should collimate almost every time out.
So for the first weeks to months I would be there with a cheshire eyepiece. Tweaking and resetting.
Then I began to realise that I was turning screws and putting them back to their original positions.
The next 'light bulb moment' was when I realised that as I wasn't bouncing it up and down stairs, there was no good reason for collimation to shift between outings.
After that it got very little attention to collimation and I had nothing to indicate problems, despite it being an F4 scope.