Not sure which scope to get (looking at two different ones)

[SthBohemia]

@k_martensen if you desire a scope with excellent optics... Grind yourself a primary mirror and figure it to 1/16 th wave length or better🙂 Maybe if your first effort 1/8 is good enough, NOT RMS, all zones to be either under or over corrected 🙂  I realise you have purchased a scope but consider making your own over the next few months, years or decades!

I find it amusing that many within SGL advise those that purchase the mass produced, off the shelf 'things that masquerade as telescopes', to purchase decent eyepieces, 😞 Why bother? The cheap crap eyepieces that accompany the scopes match (possibly) the optical quality of the scopes themselves! Ye canna make a silky purse from da sows eyries.

[bingevader]

For fear of feeding the troll! 🙄

Many of us don't have the time to make our own telescopes.

I, for one, am very happy with my mass produced masquerade and cheap eyepieces.

As you find it all so amusing, I'm sure you will stay, but if you don't like the advice given on the forum, there's a simple means to avoid it.  

[Stu]

1 hour ago, SthBohemia said:

@k_martensen if you desire a scope with excellent optics... Grind yourself a primary mirror and figure it to 1/16 th wave length or better🙂 Maybe if your first effort 1/8 is good enough, NOT RMS, all zones to be either under or over corrected 🙂  I realise you have purchased a scope but consider making your own over the next few months, years or decades!

I find it amusing that many within SGL advise those that purchase the mass produced, off the shelf 'things that masquerade as telescopes', to purchase decent eyepieces, 😞 Why bother? The cheap crap eyepieces that accompany the scopes match (possibly) the optical quality of the scopes themselves! Ye canna make a silky purse from da sows eyries.

Your comments are simply wrong. I have used both Heritage 130p and 150p scopes (still have the 150p), and have been surprised by their capabilities. Yes they are f5, but to my eye they perform very well when used with good eyepieces. I’ve had decent views of Mars showing significant detail plus split some reasonably tight doubles cleanly (Pi Aquilae as an example). I’ve owned many scopes, including 8”, 10” and 12” Orion Optics dobs with 1/10th wave optics so do have something to compare with.

Recommending someone who is just starting out to grind their own mirror (and by extension, build their own scope) is not helpful.

[Andy ES]

32 minutes ago, Stu said:

Recommending someone who is just starting out to grind their own mirror (and by extension, build their own scope) is not helpful.

Unless you’re Sir Isaac Newton, then have a go! 😂😂😂

[Stu1smartcookie]

15 hours ago, SthBohemia said:

I find it amusing that many within SGL advise those that purchase the mass produced, off the shelf 'things that masquerade as telescopes', to purchase decent eyepieces, 😞 Why bother? The cheap crap eyepieces that accompany the scopes match (possibly) the optical quality of the scopes themselves! Ye canna make a silky purse from da sows eyries.

Ok , playing devils advocate , i can see your point regarding the eyepieces supplied with scopes ,  but , they are there just to get people started . looking at most reviews . Those Mass produce scopes are encouraging people to take up a hobby that a few decades ago was considered elitist . And optical quality on those mass produced scopes is actually very good . What would you call those "things " that masquerade as telescopes ? 

Sure , there are a lot of factors that can spoil the hobby , Weather and light polution being two ... and those factors can be great equalizers where equipment is concerned . To be fair , there are still some awful scopes out there on the likes of ebay which are incorerctly sold with false advertising . But to label mass produced scopes the way you have , that have been recommended by users on SGL is imo wrong . 

Someone starting out in the hobby needs advice , where better to come than SGL or other forums from people who have actually used those products . 

 

 

Edited October 31, 2022 by Stu1smartcookie

[happy-kat]

I use a heritage 130p, known as the onesky in the US. Using a 6mm eyepiece I had bought I observed a moon shadow transit on Jupiter, super experience.

There are a lot of users of the onesky. That and the heritage 130p use the 130mm f5 parabolic mirror on a dobsonian mount but the OTA has a long dove tail bar so the OTA can be used on other mounts.

[Alan64]

I got this base Synta 150/750 OTA, with a plastic focusser, back in 2012...

I've witnessed snap-to focussing, and with a barlow inserted to boot, with the Newtonian.  Granted, that is not to say that it's perfect, no, as it is mass-produced.

[Zermelo]

I have three mass-produced scopes, very much standard fare. One of these is F/5.
With each incremental eyepiece upgrade I've noticed an improvement in image quality, which suggests to me that my experiences are not (yet) being limited by the quality of the OTA optics.

While the maximum magnification is often limited by atmospheric conditions in the U.K., I have been pleasantly surprised by the number of occasions that I've been able to push beyond the rule-of-thumb "twice the objective diameter in millimetres" and still get usable results. On the very best evenings, my Skymax 127 splits doubles that it shouldn't be able to.

Yes, there are still some lemons out there, which are called out on this forum and elsewhere, but my experience is that the optics on mass-produced telescopes are pretty decent.

[allworlds]

Since this is running. Spherical aberration isn't a function of f/ratio alone. My understanding is it's proportional to diameter divided by f/ratio cubed. (Or equivalently, to diameter^4 divided by focal length cubed.) The classic 4.5 inch f/8 sphere is OK, not perfect but OK, but a 9 inch f/8 sphere would have spherical aberration twice as bad.

But a 5 inch f/5 sphere is lousy. Worse than the 3 inch f/4 spheres in the mini Dobs, and they have the excuse of being a very cheap telescope with a good mount.

I'm sceptical about whether the Astromaster 130 EQ has a spherical primary or whether Celestron customer service reps just don't understand their products. I've read reports of mirrors that were poorly corrected but not completely spherical. But it's easiest to not take the chance, better scopes can be bought new. If anyone's looking at a second-hand Astromaster 130 EQ, bring along a short FL eyepiece and simply try focusing it at high power before buying. (Or better, do a star test, but a simple "will it focus at 130-ish times" test will show up a spherical primary I reckon.)

[AstroMuni]

On 30/10/2022 at 06:32, Alan64 said:

I should mention that the Q&A reply from Celestron may have been in error, I sometimes think, regarding the "AstroMaster" 130EQ.  It may have a parabola, in fact. Historically, Celestron has been tight-lipped about a lot of their specifications, for this, and for that.

I have the 130EQ and I did compare it for observing against a SW 150P. At lower magnifications its comparable to the SW, but as soon as you up the magnification to get closeup views of the moon or planets, thats when the focus becomes fuzzy. The SW does a better job at higher magnification.

I have even managed to use the 130EQ for imaging mainly DSOs and you can get pretty decent shots (see my signature). It does exhibit coma like aberration but couldnt test with my Baader CC as I cant achieve focus with this 😞

I am no expert on optics so cant confirm if mirror is spherical or parabolic.

Edited October 31, 2022 by AstroMuni

[Alan64]

5 hours ago, AstroMuni said:

I have the 130EQ and I did compare it for observing against a SW 150P. At lower magnifications its comparable to the SW, but as soon as you up the magnification to get closeup views of the moon or planets, thats when the focus becomes fuzzy. The SW does a better job at higher magnification.

I have even managed to use the 130EQ for imaging mainly DSOs and you can get pretty decent shots (see my signature). It does exhibit coma like aberration but couldnt test with my Baader CC as I cant achieve focus with this 😞

I am no expert on optics so cant confirm if mirror is spherical or parabolic.

It is only a slight, nagging thought that the reply was in error.  I still think it to be spherical, given that when a Newtonian does have a parabola, that is usually, always, touted within its sales-listing online.  The trouble in the case of this one is that Celestron simply doesn't divulge specs for their products, hence not knowing if it is or isn't, with certainty. 

I just now discovered that 130mm f/5 spherical primary-mirrors are being made overseas, and being sold on AliExpress, at least.

Did you choose, purchase your kit , and if so, what was it about the kit that had drawn you to it?

[AstroMuni]

 

13 hours ago, Alan64 said:

Did you choose, purchase your kit , and if so, what was it about the kit that had drawn you to it?

I had purchased for my daughter who was interested in Astro. I didnt do much research at that time and chose the Celestron as I had heard the brand name. It was in my budget, came with an RA tracker, 10 year guarantee and had a few decent reviews on the site I purchased it from. We struggled for a bit with the stock red dot finderscope and thats when I bought the telrad. After that it was a joy to use and as a family we have enjoyed great views of the stars and planets. I even managed to get pictures with my phone attached to eyepiece (attached below). So all in all a decent beginner scope for the price. It does have its shortcomings but hey it has brought joy to my family and continues to amaze me even today when I manage to take images of DSOs with it (its on a much better mount now)

 

Edited November 1, 2022 by AstroMuni

[Stu1smartcookie]

1 hour ago, AstroMuni said:

. After that it was a joy to use and as a family we have enjoyed great views of the stars and planets. I even managed to get pictures with my phone attached to eyepiece

That one sentence is enough to know what ameteur astronomy is all about ... enjoyment . 

[StevieDvd]

A good starter choice for the budget. and to begin the astro journey. Just because some here are overly technical and have big budgets for their equipment does not mean you won't enjoy the hobby with the scope/mount you selected. Just be happy it was not one from a supermarket - which do tend to lead to dissatisfied users.

As a possible Christmas present then a modest zoom eyepiece such as SvBony 7-21mm would be better than the starter ones they supply.

Welcome to SGL and happy viewing.

Steve

[SthBohemia]

Sighs, whatever do you lot think we did in the 60's if we wanted telescopes? WE made them! I stated somewhere else that I made my first scope aged 15-16 some 60 odd years ago along with an equatorial mount...

I have never encountered the, so named, cheap telescopes, all comments that I have made have been from CRITICISMS made by members within SGL in regard to certain aspects of manufactured telescopes!

Bottom line.. If your happy with whatever ya got so be it. I;m outa this thread, a waste of time...

[scotty38]

13 minutes ago, SthBohemia said:

Sighs, whatever do you lot think we did in the 60's if we wanted telescopes? WE made them! I stated somewhere else that I made my first scope aged 15-16 some 60 odd years ago along with an equatorial mount...

I have never encountered the, so named, cheap telescopes, all comments that I have made have been from CRITICISMS made by members within SGL in regard to certain aspects of manufactured telescopes!

Bottom line.. If your happy with whatever ya got so be it. I;m outa this thread, a waste of time...

Do you still take your clothes down to the stream to wash them? I mean you can if you wish but you don't "have" to, same with a beginner scope these days too......

[bingevader]

31 minutes ago, SthBohemia said:

Sighs, whatever do you lot think we did in the 60's if we wanted telescopes? WE made them! I stated somewhere else that I made my first scope aged 15-16 some 60 odd years ago along with an equatorial mount...

I have never encountered the, so named, cheap telescopes, all comments that I have made have been from CRITICISMS made by members within SGL in regard to certain aspects of manufactured telescopes!

Bottom line.. If your happy with whatever ya got so be it. I;m outa this thread, a waste of time...

Okay, maybe not the sixties, but definitely the 70s and 80s, I didn't have the money, time, or skills to make my own 'scope, still don't, I'm a bodger at best.

The mass and cheap production of astronomy kit was what opened this world up to me, couldn't have afforded it otherwise.

[Stu]

29 minutes ago, SthBohemia said:

Sighs, whatever do you lot think we did in the 60's if we wanted telescopes? WE made them! I stated somewhere else that I made my first scope aged 15-16 some 60 odd years ago along with an equatorial mount...

I have never encountered the, so named, cheap telescopes, all comments that I have made have been from CRITICISMS made by members within SGL in regard to certain aspects of manufactured telescopes!

Bottom line.. If your happy with whatever ya got so be it. I;m outa this thread, a waste of time...

Sir, without wishing to state the obvious, we now live in the third decade of the 21st century. Manufacturing capabilities are incomparable with what was available back then. Mass produced scopes from reputable manufacturers (Synta, GSO etc) are of a very acceptable quality, and give pleasure to thousands of people who have neither the time nor inclination to build their own scopes, nor the budget to go with ‘boutique’ brands with higher specs.

Are they faultless? No, of course not, but they do a good enough job in most instances.

[Andy ES]

On 30/10/2022 at 08:57, Alan64 said:

The cold, hard facts of life: it is more difficult, more costly, for the manufacturers overseas, to produce parabolas, at left...

Thanks, useful picture, for me anyway. 👍

[Alan64]

13 hours ago, AstroMuni said:

I had purchased for my daughter who was interested in Astro. I didnt do much research at that time and chose the Celestron as I had heard the brand name. It was in my budget, came with an RA tracker, 10 year guarantee and had a few decent reviews on the site I purchased it from. We struggled for a bit with the stock red dot finderscope and thats when I bought the telrad. After that it was a joy to use and as a family we have enjoyed great views of the stars and planets. I even managed to get pictures with my phone attached to eyepiece (attached below). So all in all a decent beginner scope for the price. It does have its shortcomings but hey it has brought joy to my family and continues to amaze me even today when I manage to take images of DSOs with it (its on a much better mount now)

There was no way of knowing at the time, of course.  Over the last few years, I have wanted an OTA of that kit, myself, as I have other mounts, and in knowledge of its characteristics.  Over the years I have also learned that, sometimes, opinions, and even recollections online do not match what a user experiences, there in the wilderness, at and in their home.

[Stu1smartcookie]

19 hours ago, bingevader said:

 

deleted due to me being confused ... it happens a lot these days 🤣

Edited November 2, 2022 by Stu1smartcookie

[Alan64]

Back to the telescope at hand...

I have this base-model 150/750...

It started out on a Dobson(or Parsons)-type base, then onto a GSO alt-azimuth, and where it came into its own, up to round 200x.

A 150/750 Newtonian enables powers from a somewhat low yet effective 23x(32mm), up to, in theory, 300x(2.5mm), particularly on the Moon.  I took this through the telescope, although at round 180x(4mm), afocally...

...and this...

At the lower and lowest powers, the telescope may serve as a finder in its own right, particularly with an even longer eyepiece, such as a 2" 38mm 70°...

https://www.firstlightoptics.com/ovl-eyepieces/panaview-2-eyepieces.html

...or even a 50mm Erfle(15x, and binocular-like)...

https://www.apm-telescopes.net/en/ts-optics-2-erfle-50mm-rich-field-eyepiece-52-field

[Knighty2112]

18 hours ago, SthBohemia said:

Sighs, whatever do you lot think we did in the 60's if we wanted telescopes? WE made them! I stated somewhere else that I made my first scope aged 15-16 some 60 odd years ago along with an equatorial mount...

If I remember rightly didn’t Brian May make his very first electric guitar also, before he went on to fame and fourtune with Queen? Sadly, never had the time (or patience) to build my own scope, although I did get a replica of One of Galileo’s first scopes from Astromedia a few years back to make, which works well (but really narrow field of view) on the moon, so does that count?  

[starhiker]

50 minutes ago, Alan64 said:

Back to the telescope at hand...

I have this base-model 150/750...

It started out on a Dobson(or Parsons)-type base, then onto a GSO alt-azimuth, and where it came into its own, up to round 200x.

A 150/750 Newtonian enables powers from a somewhat low yet effective 23x(32mm), up to, in theory, 300x(2.5mm), particularly on the Moon.  I took this through the telescope, although at round 180x(4mm), afocally...

...and this...

At the lower and lowest powers, the telescope may serve as a finder in its own right, particularly with an even longer eyepiece, such as a 2" 38mm 70°...

https://www.firstlightoptics.com/ovl-eyepieces/panaview-2-eyepieces.html

...or even a 50mm Erfle(15x, and binocular-like)...

https://www.apm-telescopes.net/en/ts-optics-2-erfle-50mm-rich-field-eyepiece-52-field

How did you reduce the brightness on the moon surface away from the shades? I can only resolve the details around the boundary of the shade part because of the brightness.

[Guest]

52 minutes ago, starhiker said:

How did you reduce the brightness on the moon surface away from the shades? I can only resolve the details around the boundary of the shade part because of the brightness.

A variable polarized filter works very well on reducing the brightness. Its a must have in my book.