Go Back   IceInSpace > Beginners Start Here > Beginners Equipment Discussions

Reply
 
Thread Tools Rate Thread
  #1  
Old 16-01-2020, 09:09 PM
Bobbyoutback's Avatar
Bobbyoutback
Registered User

Bobbyoutback is offline
 
Join Date: Oct 2009
Location: Broken Hill
Posts: 283
Black list of telescopes

I found this Russian site that lists what are the bad scopes , what do you think of the list


http://www.star-hunter.ru/en/black-list/


Bobby
Reply With Quote
  #2  
Old 16-01-2020, 09:48 PM
Atmos's Avatar
Atmos (Colin)
Ultimate Noob

Atmos is offline
 
Join Date: Aug 2011
Location: Melbourne
Posts: 6,868
It kinda just says; "Don't scape the bottom of the barrel, you get what you pay for."
Reply With Quote
  #3  
Old 16-01-2020, 10:20 PM
JeniSkunk's Avatar
JeniSkunk (Jenifur)
Registered User

JeniSkunk is offline
 
Join Date: Jul 2018
Location: Brisbane
Posts: 355
The problem with this list, is the date it was compiled. 2015-05-17.
So what new entries would need adding, to bring it to current?
Reply With Quote
  #4  
Old 17-01-2020, 12:30 AM
Bobbyoutback's Avatar
Bobbyoutback
Registered User

Bobbyoutback is offline
 
Join Date: Oct 2009
Location: Broken Hill
Posts: 283
Quote:
Originally Posted by JeniSkunk View Post
The problem with this list, is the date it was compiled. 2015-05-17.
So what new entries would need adding, to bring it to current?
Well said !
We need a updated list of these poor scopes , any major retailer still selling these need to know how bad they are .

Cheers
Bobby
Reply With Quote
  #5  
Old 17-01-2020, 01:24 PM
Wavytone
Registered User

Wavytone is offline
 
Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
There's a basis behind that list, though:

a) fast achromats will have lots of secondary colour at high magnifications. OK for a finder, but don't expect great images on the planets or moon.

b) quite a few budget reflectors have cheap spherical mirrors, where the spherical aberration will also cripple them at high powers.

c) use of low-precision plastics where metal is really needed, eg places where the point stresses are high and plastic will deform, and places where accuracy is needed. For example secondary mirror cells, and focusers.

d) hopelessly inadequate mounts/tripods,

e) poorly constructed OTA's.

Fixing these mistakes costs $. Put it another way - you won't get what you didn't pay for - ie quality.

Conversely i'd also argue that crap equipment should never have been made in the first place. It is at best useless, at worst it will disillusion kids when they find out what they have was crap from the start, and its sole purpose was to extract money from parents pockets.
Reply With Quote
  #6  
Old 17-01-2020, 04:04 PM
Bobbyoutback's Avatar
Bobbyoutback
Registered User

Bobbyoutback is offline
 
Join Date: Oct 2009
Location: Broken Hill
Posts: 283
example

Fully agree with what Wavy said !
A recent example of a GoTo mount that can't seem to find things .
I've asked a clever mate to try & find a fix .

He sent the following email today :


Following a partial disassembly I have discovered the fault lies in the drive mechanism to mount fastening devices - ie the scope plastic mounting structure (and Alt drive assembly) is not perpendicular with the AZ drive plate.
The attached image shows the lower cup attachment (metal cup that secures the whole assembly to the tripod) and a dark grey fibre washer.

This washer is the only thing holding the large drive gear to the assembly and also acts as a friction brake to stop overrun.

The larger assembly (main body that precesses) has 3 equi-distant white silicone pads (dots) that act as bearings on the outer surface of the lower cup attachment.

They decided to assist the bearing surfaces by smearing grease ( with the consistency of Yellow Box Honey) on the lands (bearing surfaces)of the lower cup - and subsequently turned it into a high drag surface area. Probably why low speed slew has a hard time moving. (DC motor variable speed and constant torque).

I am now going to remove the outer covers and examine the mountings for the Body to AZ assembly - more discoveries to come!

As a rough estimate and envisioning the 1-2mm deviation of the AZ base) I would give a few arc minutes of error!
Attached Thumbnails
Click for full-size image (20200117_103221.jpg)
194.0 KB119 views
Reply With Quote
  #7  
Old 17-01-2020, 07:52 PM
Nightingale
Registered User

Nightingale is offline
 
Join Date: Nov 2019
Location: Adelaide
Posts: 44
Just glad that my meade 12inch ACF is not on that list!🤣
Reply With Quote
  #8  
Old 17-01-2020, 08:22 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 9,955
In my experience, ANYTHING made by iOptron needs to be on a list, as well as North Group/ Explore Scientific. Just gad awful.
Reply With Quote
  #9  
Old 17-01-2020, 10:15 PM
JeniSkunk's Avatar
JeniSkunk (Jenifur)
Registered User

JeniSkunk is offline
 
Join Date: Jul 2018
Location: Brisbane
Posts: 355
I'm glad my SkyWatcher 130mm tabletop Dobsonian is not on the list, as I noted a few other 130mm reflectors by Synta were on it.

What's curious to me, though, is there's no mention of any Saxon scopes on the list.
Reply With Quote
  #10  
Old 17-01-2020, 11:38 PM
Bobbyoutback's Avatar
Bobbyoutback
Registered User

Bobbyoutback is offline
 
Join Date: Oct 2009
Location: Broken Hill
Posts: 283
Quote:
Originally Posted by JeniSkunk View Post
I'm glad my SkyWatcher 130mm tabletop Dobsonian is not on the list
.
Your scope has a parabolic mirror if it had a spherical mirror it would probably be on the list .

Cheers
Bobby .
Reply With Quote
  #11  
Old 18-01-2020, 08:25 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 19,684
my first scope is on that list. Still enjoyed it for years.
Reply With Quote
  #12  
Old 18-01-2020, 08:33 AM
JeniSkunk's Avatar
JeniSkunk (Jenifur)
Registered User

JeniSkunk is offline
 
Join Date: Jul 2018
Location: Brisbane
Posts: 355
Quote:
Originally Posted by JeniSkunk View Post
I'm glad my SkyWatcher 130mm tabletop Dobsonian is not on the list, as I noted a few other 130mm reflectors by Synta were on it.
Quote:
Originally Posted by Bobbyoutback View Post
Your scope has a parabolic mirror if it had a spherical mirror it would probably be on the list .
Indeed.
But it doesn't make sense to me, that at the mass production budget end of the manufacturing spectrum, that they would use 2 different designed mirrors, for the collapsible, and solid tube, 130mm/650mm Newts. It's the solid tube Newts that got listed.
Reply With Quote
  #13  
Old 18-01-2020, 08:37 AM
mental4astro's Avatar
mental4astro (Alexander)
kids+wife+scopes=happyman

mental4astro is offline
 
Join Date: Jun 2008
Location: sydney, australia
Posts: 4,863
I take a bit of a different view on "junk" scopes.

For us who have experience and know what is decent in quality, we won't even look sideways at these instruments.

However, I would dare say that for the majority of people, this is all the scope they would actually need. You can make all your lists of crappy scopes you want, but rightly or wrongly these actually do fill a niche.

The purchasing officer of a big retailer is not interested in astro like we are (I'm not talking astro retailers here). The vast majority of these folks unfortunately are totally ignorant of what makes a quality instrument. ALL they know is sales and that is their only motivating factor - selling bucket loads of product. If anything, these people know human nature better than we here on this forum because they are selling not only what most people will buy, but the very reason as to why - price. And our own astro insight can go take a hike. They may have a few decent scopes on offer too, but there is no actual knowledge that goes into these stock decisions by the purchasing officer - they just go by what range is put to them by a distributor and choose just a few "big and complex looking" scopes for their store. While on the topic, you think there is any real knowledge into what Curious Planet offers scope wise, or that any of their their staff know what an SCT is?

EVERYONE starts out in astro from ZERO. Unfortunately, most people have such a poor understanding of what the Universe looks like through a scope. So, not withstanding what quality of scope they look through, they EXPECT to see the Universe through ANY scope just like a Hubble image. The image advertising spin ALL scope brands push out does not help. Heck, even at outreach events where ALL you will find a good quality scopes, so many people are totally underwhelmed by what they, even through a 20" dob. A "quality" scope will not change things for them. There are thousands upon thousands of SCT's and decent dobs out there, yet the fraction of these scopes see any star light beyond half a dozen times. What good was getting a good quality instrument then?

Many people would do some research into what makes a good scope. Unfortunately for most people they see the price tag on scopes across the quality spectrum and that is as far as their research goes and opt for the plastic-fantastic. Others despite their best of intentions, do their "reading" but ultimately it really is all just gobbledygook because they cannot relate to the info and don't have anyone with knowledge to guide them, so they end up buying cheap. They just cannot relate.

Another person who has a strong desire to look up at the night sky may only be able to afford a plastic-fantastic. They would love to get a better instrument, but no chance because of financial pressures. Damn if that plastic-fantastic would not be treated like it was made of gold, and after all the best scope is the one that is used. Yet how many good quality scopes just end up in a garage after a couple of uses...

A parent who sees in their child a glimmer of curiosity in astro, science and learning, wants to push along this interest, but full well knows that this curiosity can be fickle. They get a cheapy scope in the hope that it will capture their kids imagination. And the rate of that fish biting is always very small, and it will not matter the quality of the scope. Not in the slightest.

And the last point - astronomy is all rocket-science... Most people look at ANY equatorial mount, be it an EQ1 or AZEQ6, and they are absolutely terrified by it! I have seen teachers with 30 years experience who have seen all manner of things (including science teachers! ) be totally terrified by the 114 Newt on an EQ1 mount the school has! I mean seriously terrified by it even though they have connections with amateur astronomers (me in this instance). The scope is really nothing more than a decoration that can do nothing more than to "inspire" students as no one will put it to use. I saw that scope over some two years in a school and in the end asked about it as I noticed it just wasn't being used. The teachers told me they were all scared of it! I offered to make a dobby mount for it as I said it is a much easier scope to use. They accepted, and I even conducted an outreach event for that school and that little new dob was also one of the scopes used on the night. To my great disappointment that little dob didn't get used either - now the teachers found the night sky too intimidating In the end those same teachers asked me to take it and give it to someone who would put it to use.

All too often at outreach I see people approach my dobs, SCT and Mak with great scepticism, mistrust and sometimes even FEAR that these are actually scopes. They can only relate to a telescope as being only what a pirate uses, and that what professional astronomers use is nothing short of "star trek". Many of these people will only ever buy a plastic-fantastic because it is all they can relate to. Very few will stick with astro to progress any further with it, regardless of how good a quality instrument they do buy.

I started when I was 13 with a 2" Tasco refractor that had a table top mount, and really poor eyepieces (I didn't know that then). I cut my teeth with it! I modified it like all heck, putting it on a photo tripod, modifying the tripod to improve its stability, learned to star hop, learned about averted vision. Damned if it also showed me an oh-so-faint tail on Halley's Comet from to roof of my home in Surry Hills in Sydney, and "discovered" Saturn by chance! It was all my mum and dad could afford. I still have that little scope too . Yet I know of so many 8" dobs that are rotting away in damp garages... I would have killed to have one of those suckers when I was 15!

Alex.
Reply With Quote
  #14  
Old 18-01-2020, 08:44 AM
Outcast's Avatar
Outcast (Carlton)
Always gonna be a NOOB...

Outcast is offline
 
Join Date: Oct 2008
Location: Cairns, Qld
Posts: 1,054
Okay, I'll bite...

There are several refractors on the list that I would hardly put on a black list...

Sure, they are achromats.. sure, they show false colour, like pretty much every achromat ever built... so what??

When the stated reason for it being on the black list is...'Fast Achromat' I shrug my shoulders & think... so what...

I've owned a 'fast achromat' in an Orion Short tube which is essentially the same scope as the SW/Synta listed... actually, as an achromat, it was pretty damn good... false colour, yep.. on bright stuff... pretty much like every achromat ever built really... which is why doublets & triplets evolved... to my mind, doesn't make them a 'black listed' scope though...

My little TS Optics RACI finderscope, a 60mm f4 (so another fast achromat) actually produces some stunning views of open clusters, so much so that I'm still toying with the idea of buying a canon lens mount so I can put it on camera tripod to take on plane trips.. doesn't get much lighter & smaller for grab & go...

My point being... 'fast achromat' hardly seems like a solid reason to 'black list' a scope...

Just my thoughts on how objective/subjective the list may be...

FWIW, I don't own any of the scopes listed so, have no self interest in justiying why any of these scopes should or shouldn't be on the list... just doesn't seem to necessarily be particularly objective in some cases nor do they explain in any detail why it's on the list except, perhaps where it's on a carp mount... which I would agree with whole heartedly, having looked through cheap scopes on garbage mounts..
Reply With Quote
  #15  
Old 18-01-2020, 10:19 AM
Wavytone
Registered User

Wavytone is offline
 
Join Date: Jul 2008
Location: Killara, Sydney
Posts: 4,147
Alex appreciate that view, but to be honest the world really seriously needs to stop producing cheap junk that will finish up in landfill or worse, floating around in the sea (plastics).

The short term selfish interests of retailers do not justify destroying the environment.

While on holiday on Lord Howe island - one of the most isolated, pristine marine environments - I conducted a little exercise to see how many macroscopic pieces of plastic haf washed up on it’s shores - about 1-5 per square metre. Pretty sad result IMHO.
Reply With Quote
  #16  
Old 18-01-2020, 11:03 AM
mental4astro's Avatar
mental4astro (Alexander)
kids+wife+scopes=happyman

mental4astro is offline
 
Join Date: Jun 2008
Location: sydney, australia
Posts: 4,863
Gosh, Wavy, plastic lenses and the flow on into the ocean is a bit of a stretch!

Most of these cheap scopes though are still make of glass and metal. Plastic components are on ALL scopes, cheap and expensive. There are some brands that provide "good" quality instruments, but they are well known in our world as still being a compromise of cheap and quality. But some also provide some real crap with minimal plastic...

I am not justifying retail greed. But it is not reasonable for us on this forum to be all righteous and evangelical by ignoring the realities of the world we live in (commercial, manufacturing and family). We need to keep a sensible perspective on this topic here. There is good that has come about from this cheap stuff, not just bad.

And it really goes without speaking that we SHOULD be weaning ourselves off our dependency on plastic.
Reply With Quote
  #17  
Old 18-01-2020, 12:32 PM
raymo
Registered User

raymo is offline
 
Join Date: Sep 2011
Location: margaret river, western australia
Posts: 5,465
Even a budget 60mm frac will elicit a Wow from a newbie when aimed at
Saturn, or even the moon; the biggest problem IMHO is that such scopes
at budget level are almost always on woeful mounts that make it an exercise in wobbly frustration.
raymo
Reply With Quote
  #18  
Old 18-01-2020, 03:23 PM
Bobbyoutback's Avatar
Bobbyoutback
Registered User

Bobbyoutback is offline
 
Join Date: Oct 2009
Location: Broken Hill
Posts: 283
Quote:
Originally Posted by JeniSkunk View Post
Indeed.
But it doesn't make sense to me, that at the mass production budget end of the manufacturing spectrum, that they would use 2 different designed mirrors, for the collapsible, and solid tube, 130mm/650mm Newts. It's the solid tube Newts that got listed.
Jen ' I think the reason is who's $bucks they are targeting .
You bought the right choice ' did you know beforehand or did research ?

I recently tried out a pair of fixed focus binoculars , the image was crook so I reached for the focus wheel that didn't exit , beats me how these actually sell as they're horrible

Bobby .
Reply With Quote
  #19  
Old 18-01-2020, 03:37 PM
leon's Avatar
leon
Registered User

leon is offline
 
Join Date: Apr 2006
Location: ballarat
Posts: 11,162
That,s a hell of a long list of scopes but i have to agree with Alexander some of these scopes would suit some people, who just want to look every now and then.

Leon
Reply With Quote
  #20  
Old 18-01-2020, 08:10 PM
JeniSkunk's Avatar
JeniSkunk (Jenifur)
Registered User

JeniSkunk is offline
 
Join Date: Jul 2018
Location: Brisbane
Posts: 355
Quote:
Originally Posted by Bobbyoutback View Post
You bought the right choice ' did you know beforehand or did research ?
I did, what I thought, was plenty of research, checking the reviews, reading about how the various budget scopes performed, and looking for known issues.

The major stuff I was worrying about was how much physical footprint did the scope need. I don't recall any mention of the design of primary mirrors in the reviews, though.

Now that I know a bit more, I know of what other details to check for in reviews. It's like a few days back, when I learned of the Curious Planet bankruptcy closing down sales. One scope I noticed on their site, was the Celestron Travel Scope 70. Reading the reviews turned me off that scope, fast. Cheap defective manufacture, and then I learned of this thread, and found that Celestron is in the Black List.

Quote:
I recently tried out a pair of fixed focus binoculars , the image was crook so I reached for the focus wheel that didn't exit , beats me how these actually sell as they're horrible

I have to laugh at that. You'd hit the same non-existent focus knob issue on my 10x50 binoculars. They're individual eyepiece focus.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 09:58 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
NexDome Observatories
Advertisement
Bintel
Advertisement
Limpet Controller
Advertisement
Astronomy and Electronics Centre
Advertisement