Buying telescope from SharpVision India. Need reviews

[Acis Ace]

After months of browsing the web I've finally decided to buy a 6" f/7 Telescope from SharpVision India (Mr. Viresh Mathur).

The one I'm buying is on a dobsonian mount and is named Galaxy II. 

Can anyone give me any details about how his telescopes perform and particularly the above model.

I am also planning to buy a plossl eyepiece with it.

Thanks.

[sathya kumar Prasanna]

Firstly, I have never heard of this company.

Secondly, the dobsonian telescope sure is cheaply priced, but the photo itself shows how badly made it is. You can clearly see the exposed edges of the "Prticle board" dobsonian mount. When you use this mount where moisture is a concern, the board is most likely going to swell up. My advice, as an experienced user of telescopes is that you should not look for "Cheap and Best" in astronomy, because if its cheap, it probly is so in terms of quality too, and if if its slightly high priced, then the workmanship will also be equally better.

Please send me a personal message and I will tell you where to buy good branded telescope in Bangalore for a reasonable price.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

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[keerthi kiran]

Sathya,

Since you are a vendor of telescopes yourself, you should mention that in your replies when you comment about other vendors.

Thanks and Regards,

Keerthi

[sathya kumar Prasanna]

I assumed that direct selling was against the BAS policy itself.

Anyway, yes, I am a vendor of telescopes. 

No, I did not point out anything incorrect. Any experienced telescope user can tell that one look at the dobsonian mount itself will show the flaws I pointed out.

As far as the optical quality of the mirror is concerned, I cannot comment on that.

I am certain that Sky-Watcher telescopes, which I market are diffraction limited at the very least.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

[Akarsh Simha]

I am not making a statement about you in particular, Sathya, because
you are one of the most educated people on this mailing list on these
matters;

A generic dealer's opinion might be inclined to be biased against the
competition just by virtue of his position, despite it being written
in all honesty and with a pure intent to help the consumer. Hence, I
think it is fair that on the BAS mailing list, dealers are asked to
self-introduce whenever there is a potential conflict of interest. So
thanks for doing so. I don't think Keerthi's e-mail is a criticism of
the contents of your response, just of this policy, which we will
attempt to enforce universally and uniformly.

Regards
Akarsh
One of the several moderators.

2016-04-01 3:03 GMT-05:00, sathya kumar Prasanna <skps...@gmail.com>:
> I assumed that direct selling was against the BAS policy itself.
> Anyway, yes, I am a vendor of telescopes.
> No, I did not point out anything incorrect. Any experienced telescope user
> can tell that one look at the dobsonian mount itself will show the flaws I
> pointed out.
> As far as the optical quality of the mirror is concerned, I cannot comment
> on that.
> I am certain that Sky-Watcher telescopes, which I market are diffraction
> limited at the very least.
>
> Thanks and Regards
> Mr. Sathyakumar Sharma,
> Scientific Officer,
> Karnataka Science and Technology Promotion Society,
> DST, Govt of Karnataka,
> Banashankari 2nd Stage,
> Bangalore.
>
> Phone: +91 8095626184

> http:/ <https://www.facebook.com/SathyakumarSharma>/
> sharma-astronomy.weebly.com

>>> http:/ <https://www.facebook.com/SathyakumarSharma>/
>>> sharma-astronomy.weebly.com

>>>
>>> On Fri, Apr 1, 2016 at 12:22 PM, Acis Ace <acis...@gmail.com> wrote:
>>>
>>>> After months of browsing the web I've finally decided to buy a 6" f/7
>>>> Telescope from SharpVision India (Mr. Viresh Mathur).
>>>> The one I'm buying is on a dobsonian mount and is named Galaxy II

>>>> <http://www.sharpvisionindia.com/prod1.htm>.

[Harshad RJ]

On Fri, Apr 1, 2016 at 12:22 PM, Acis Ace <acis...@gmail.com> wrote:

After months of browsing the web I've finally decided to buy a 6" f/7 Telescope from SharpVision India (Mr. Viresh Mathur).

​

​I can chip in with a review of the company; no idea about the telescope.​

I had bought some components from this company while​ building my own dobsonian telescope, including spider, mirror mount, finder scope, and some basic eyepieces.

I would say the products were value-for-money, with ok craftmanship. I knew this before buying, so I was satisfied with the deal. The products are still working fine.

--

Harshad RJ

[keerthi kiran]

Hello Acis Ace,

Telescopes are available in many sized and price ranges. Quality of the optics used matters a lot. Apart from optics, you should also be concerned about the mechanical build quality (telescope and its mount or stand should not be shaky).

If you need better optics and stable mount, you will have to spend more money. If you are constrained with the budget, you can go for the cheaper options.

Thanks and Regards,

Keerthi

--

[Acis Ace]

They are indeed diffraction limited.
I mailed Mr. Mathur asking for the specifications. The mirrors are polished to 1/8(RMS) and the scope comes with two ewF kellners. I also aaked some people at AAA Delhi and they recommended the manufacturer.

[Anjaneya Thimmappa]

.

On Friday, April 1, 2016 at 8:45:58 PM UTC+5:30, Acis Ace wrote:

They are indeed diffraction limited.
I mailed Mr. Mathur asking for the specifications. The mirrors are polished to 1/8(RMS) and the scope comes with two ewF kellners. I also aaked some people at AAA Delhi and they recommended the manufacturer.

 

,hello acis ace....i saw the scope on the link provided..it doesnt look great, instead  why dont you buy a good bino for the same 

price..it will come a long way...decision is yours

[ANAND LATHA]

Could a binocular give such an image as formed by a 6 inch telescope. I know viresh mathur the owner and proprietor of Sharp vision India
As I have send my six inch mirror to him for for reconfiguration and aluminuzing and also ordered for eyepiece ,diagonal mirror, mirror mount etc..I think that telescope would be good.but the final decision should be yours.

Thanks and regards
Anand .K.N

--

[Acis Ace]

Actually, I arrived on it after considering the Startracker dobsonian from tejraj co. which boasts GSO optics figured to 1/12(RMS) wave (and better eyepieces).

I am of the opinion that the fact that the mirror in the sharpvision telescope is india made is responsible for the lower cost (and there isn't much visible difference b/w 1/8 and 1/12 wave accuracy). 

Which would you choose from the two - given that the startracker costs about rs 5000 more than the galaxy II ?

Thanks

PS. I am likely joining IISc Bangalore in UG program this year. Anyone from the college here ?

[Akarsh Simha]

>
> PS. I am likely joining IISc Bangalore in UG program this year. Anyone from
>
> the college here ?

I'm not from IISc, but if you are interested in physics or biology,
you might gain some benefit from the REAP programme in the
planetarium.

Regards
Akarsh

[Rasik Mhatre]

Does not C-sky offer the same?

 

Rasik Mhatre

Cell: +91-7798466222

Landline: +91-20-26717018

A15/202 Brahma Avenue

Off NIBM Road

Kondhwa,

PUNE 411048 INDIA

SKYPE ID: rasikdon

--

[Karthik Subramanian]

On Sunday, 3 April 2016 07:54:30 UTC+5:30, Acis Ace wrote:

Which would you choose from the two - given that the startracker

costs about rs 5000 more than the galaxy II ?

PS. I am likely joining IISc Bangalore in UG program this year.

Anyone from the college here ?

I'd respectfully suggest that cost alone shouldn't be the deciding factor

in buying a telescope. These are expensive purchases, and you don't

want to buy something that deteriorates badly over time. The optics 

should usually be fine as long as they were good to begin with, and are 

maintained well. The mechanical bits can degenerate unless the build

quality was up to scratch. 

If it is at all possible, I would recommend that you try out the telescope

that you want to buy. Perhaps someone else has another piece of the

same model? You could always ask the Sharpvision folks if they can

put you in touch with other satisfied customers.

Why would you want to do this?

Firstly, it would give you the opportunity to star-test the scope, and see

for yourself if the mirror is good enough for your purposes. (It's not the

same as star-testing the scope you will eventually buy, but it's a good

first approximation).

Secondly, it would also give you an idea of the mechanical aspects of

the scope /after/ it's been in use for a while. For example, with Dobs,

you'll want to see if the motion is too smooth, too sticky, or both. 

The 'both' could manifest itself as the Dob being sticky up to a bit,

and then suddenly becoming smooth, resulting in you overshooting

the target when attempting to track. This, IMHO, is worse than the

action being too sticky or too smooth. It is also an indicator of the

build quality not being very good.

Thirdly, it would also give you a rough idea of whether or not the

"irritations" in the scope are things you are willing to live with, or not.

A last couple of things - 

If your budget is hard-limited (as is the case with most of us), you

might also want to consider buying used equipment. The observing

season is about to end in Bangalore, and this is usually the time that

people start thinking about buy/sell decisions.

Also, if you buy a scope now, there's typically not much chance that

you'll be able to use it between May and November in Bangalore. If

that is your primary use-case, I'd suggest that you wait a bit :)

Best of luck,

K. 

  

[sathya kumar Prasanna]

Acis ace, adding to what I mentioned above, telescopes are available from a few thousand rupees, to several lakhs of rupees. The amount of money does not dictate the size, but quality does dictate the cost.

Mirrors or lenses have to be made with care, ideally. Mass production companies like Celestron, Sky-Watcher and Meade among others setup some form of processes which take care of a minimum quality standard. However, small companies have no way of ensuring the same. By saying so, I am not belittling the Sharpvision company, but just telling a simple fact.

Additionally, with a known brand, the customer service also tends to be generally better. I for one, always tell my buyers that they are free to call e even at 10PM, nd I will answer their queries. Why? Because I am an amateur astronomer myself and I know that it is very important to do so.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

[sathya kumar Prasanna]

Unfortunately, in India price plays the biggest factor over quality. People want a cheap instrument and the general assumption is that if its cheap and its big, then it must also be good. Its like going to market and asking the vegetable seller as to how much do carrots cost. One says 40rs, other says 30rs. We will buy the 30rs ignoring the fact that a couple of the carrots will usually be bad. 

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

[sathya kumar Prasanna]

Very good explanation Karthik.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

--

[sathya kumar Prasanna]

Ok, 

Firstly, the Kellner optical design of eyepieces have roughly 40deg AFoV and are best used in long focal length telescopes.

I would doubt the "oral claim" of the Mr. Mathur that the mirrors are 1/8th RMS. Polishing a mirror to that high an accuracy will be very expensive.

If that telescope is in your budget and you like it, please go ahead. But as a person with 16 years of experience in astronomy as well as telescope making, I seriously doubt Mr. Mathur's claims. The particle board mount is itself a give away.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

On Fri, Apr 1, 2016 at 5:30 PM, Acis Ace <acis...@gmail.com> wrote:

They are indeed diffraction limited.
I mailed Mr. Mathur asking for the specifications. The mirrors are polished to 1/8(RMS) and the scope comes with two ewF kellners. I also aaked some people at AAA Delhi and they recommended the manufacturer.

[Akarsh Simha]

> Unfortunately, in India price plays the biggest factor over quality. People
> want a cheap instrument and the general assumption is that if its cheap and
> its big, then it must also be good. Its like going to market and asking the

Tangentially on this topic:

I remember the time when I wanted to make a telescope. Despite my
general lack of skill, I decided I wanted an 8", not a 6" -- nearly
double the aperture, I thought. But then, I used Tejraj's uncoated
Huygens-Ramsden eyepieces for the longest time -- so what was the
point? Granted, since the telescope was ATM'd, there was not a big
cost difference between 8" and 6". But this is an easy fallacy to fall
into.

There are so many things that matter more than the size of the
telescope. For planetary observation, the other factors that matter
are:
1. How quickly does the tube cool down?
2. Do we have a fan running?
3. Do we have some stable tracking so we can crank up the power?
4. How good is the seeing?
5. Quality of eyepieces (should not have too much internal scattering)

My 18" doesn't do a good job on planets when the mirror is hot, so I
go back and observe at 85x -- might as well observe with a 4"
telescope instead, then. There are very few occasions where conditions
and my telescope have co-operated to perform really at their optimum,
and I was seeing Encke's gap. Last month, Jupiter looked like crap.
Poor seeing and lots of tube currents. No point.

For deep-sky observation, the other factors that matter are:
1. Dark skies (extremely important)
2. Transparency (very important)
3. Good baffling and shrouding (very important)
4. High contrast eyepices that are multi-coated on all surfaces, don't
have scattering etc. and have as few elements as is comfortable.
5. Good seeing and a cool mirror (if we're looking for detail beyond 200x)
6. Knowing what eyepieces and filters to use on what objects
7. Tracking

These are what contribute to a good deep-sky observation. If you buy
an 8" and are not willing to drive at least 50km to a darker site,
what is the point? I drive at least 160km each way every time
(granted, it's easier here). There are at least two occasions where
I've looked through a 30" telescope and been totally unimpressed with
the view. In one case, I've even come back to my 18" and said "ah,
that's better". Why? Because of poor shrouding -- or the lack of know
how to use the correct magnification. Hemant's 5" refractor never
ceases to amaze me -- in dark skies, it challenges my 18" on some
objects.

Then there are eyepieces. I once made an observation of Arp 148
without tracking and with an old Type I 9mm Nagler, in the most
beautiful skies I've ever seen. After almost half an hour of struggle,
I pulled out just a T-shape and nothing more. Now, with tracking and a
10mm Delos (much better eyepiece), in less-than-amazing skies, managed
to pull out even more detail.



Regards
Akarsh

[Arun Venkataswamy]

Hi Acis Ace,

I don't know about the telescope you mentioned. But my fascination to the night sky was initiated through a Sharp Vision small reflector. It was way back in '84 I think. The hint of Saturn's rings is still clear in my mind. But  go by advise on this thread while choosing your scope.

Regards,

Arun

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Known is a drop, Unknown is an ocean

[Sanath Kumar]

Hello all,
a very interesting thread indeed, there is always a balance between Cost vs quality as we often will have to decide with limited funds, so the question is how to balance this, from my experience, not just in astronomy but even while purchasing electronics or any other stuff, i usually try my best to get the goods which are by known company and has good reviews, when it comes to telescopes and accessories its a little tricky. One of the reasons being that we don’t have any astronomy expo from the sellers, we have to rely on the community and members and can only see the instruments in star parties usually, now a user is supposed to have seen the telescope and its working and then decide if they want to buy it.

few points to note :
—> better quality will last longer
—> we work in dark under cold temperatures where nothing is in our favor, so we want everything to work just right.
—> products with higher mechanical stability will give better sky watching experience


@ Acis Ace

regarding this sharp vision, i wouldn’t comment except for a few points which satya has put up and is logical
i.e. more the reputation and popularity of a company, higher will be their quality control, and they will have enough money to buy good instruments to make and check the mirror, which is highly unlikely to be found at an Indian dealers facility, claiming 1/8th wave is easy, but unless any of us have used the telescope we will never know.
so, if you are open to testing and don’t mind losing money if the telescope is bad then i think you can still go ahead with the purchase, but if you want 100% quality assurance then probably you should reconsider the options.

there are 2 popular brands in india now 1) skywatcher 2) GSO, there are also others like orion,meade , but they are expensive as the dealer wants to advertise about the GSO/skywatcher more, i have an 8” GSO dob, and i should say that i am really satisfied with the mechanical aspects of it, the optics are also good, but not the best in the world, the views are high contrast and have helped me with a lot of quality observing.





Regards,
Sanath Kumar

………………….
Sent from OS-X

[Akarsh Simha]

Hi

To play devil's advocate though, your scope choice depends on what you
want to do with it.

If you are just looking for "faint fuzzies" / "smudges of light", and
you don't care about tiny features; if you will never put a power
larger than 100x on it -- probably all of the RMS stuff just doesn't
matter. When he figured my 8" telescope, Dilip Kumar of ABAA told me
that my mirror had slight astigmatism, but something I wouldn't even
notice. And I didn't.

If you take this attitude, you should be a visual deep-sky observer of
the beginner kind. Both planet observation and astrophotography
require optical quality. Deep-sky observing benefits from any increase
in aperture, so if your aims are very clear, an increase in aperture
at the cost of quality might not be completely off the charts. When
you're looking at some of those tiny interacting pairs / Arp galaxies,
the mirror quality will really matter. Some of the galaxy observations
I reported from last night were made at 450x power. If that's what you
fight for, you really need quality (and seeing).

Finally, poor mechanical build can be very frustrating to deal with.
If your scope vibrates every time you move it and takes 10s to settle,
that can be very frustrating to deal with. But you're probably a
science/engineering student, maybe you can tune the mass and damping
to suppress the oscillations. But you're not getting a truss dob. I
think a simple tube telescope is not complicated enough that it is
unfixable. That being said, I say this as someone who has done
astronomy for way too long.

Also, Meade (and Orion too?), as far as I can tell, make their mounts
out of particle board. This is not fun, but brings down costs. If I
remember Meade Lightbridge is a particle-board Dobson, even as big as
16". I remember a friend who owns one complaining about it. Heck, a
good chunk of IKEA's furniture is particle board.

The general problem with telescopes is that they are a precision
scientific apparatus that is sold to general public. I think it has
taken me 15 years now to learn how to use a telescope correctly, and I
might still be wrong (with regards to collimation, especially).

Regards
Akarsh

[Acis Ace]

Okay, So after recommendations by many experienced people here, I've decided to go with the 6" dobsonian from tejraj and Co. mumbai.

i.e. this one:

http://www.tejraj.com/startracker-6inch-dob.html

I hope it will go a long way with the hobby.

Thanks for your support people.

And my real name is Bhaskar.

[Rasik Mhatre]

Would recommend you try http://www.skywatcher-india.com/Product/CategoryType/15 first.

 

More reliable.

 

Rasik Mhatre

Cell: +91-7798466222

Landline: +91-20-26717018

A15/202 Brahma Avenue

Off NIBM Road

Kondhwa,

PUNE 411048 INDIA

SKYPE ID: rasikdon

 

From: b-...@googlegroups.com [mailto:b-...@googlegroups.com] On Behalf Of Acis Ace
Sent: Tuesday, April 5, 2016 08:41
To: Bangalore Astronomical Society <b-...@googlegroups.com>
Subject: [-BAS-] Re: Buying telescope from SharpVision India. Need reviews

 

Okay, So after recommendations by many experienced people here, I've decided to go with the 6" dobsonian from tejraj and Co. mumbai.

--

[Sanath Kumar]

Hey Akarsh,

                 totally agree with your points,

I also wanted to clarify that my 8" do from GSO although is very good it has low order astigmatism, SW mirror which my friend got is way better in this one aspect, also specially for the 6", I think SW is better than GSO, also Tejraj  and Co doesn't care about his customers, he will tell you to bring the telescope to him for service which is not possible for someone living in bangalore, but chances of these instruments breaking are very thin, provided one uses them property.

--
Sent from iPhone

[sathya kumar Prasanna]

End of the day, GSO and Sky-Watcher are all mass produced in a fully automated Chinese factory. The quality of a mirror typically depends on the particular "Production Run" or the "Batch" that the mirror was a part off. Same thing goes to the wood used, focusers, finders, eyepieces etc. If one is bad, the entire batch is typically bad. If one is good, the whole batch will be great.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

--

[Karthik Subramanian]

On Tuesday, 5 April 2016 14:31:30 UTC+5:30, sathya kumar Prasanna wrote:

End of the day, GSO and Sky-Watcher are all mass produced in a fully

automated Chinese factory. The quality of a mirror typically depends on the

particular "Production Run" or the "Batch" that the mirror was a part off.

Same thing goes to the wood used, focusers, finders, eyepieces etc. If one is bad,

the entire batch is typically bad. If one is good, the whole batch will be great.

True enough :)

I've seen the "sticky-smooth" problem happen in a SkyWatcher (an 8" collapsible Dob),

as well as in an Orion (an older 8" Dob). In both cases, a little spur (or something) on 

the rocker box "bucket" had cut a little groove in the Alt bearing.

I was even toying with the possibility that the boxes for both were made by the same

manufacturer before I realized that the scopes were not of the same vintage.

That apart, I've read enough accounts of people complaining about how their large

Dobs just out of the box were so unbalanced that a slightly heavy eyepiece would

send the OTA slewing hurriedly towards the ground :)

No matter what 'scope one buys, I guess one has to be prepared for something to

be at least slightly off-kilter - especially if it's a Dob.

K. 

[Akarsh Simha]

> True enough :)
>
> I've seen the "sticky-smooth" problem happen in a SkyWatcher (an 8"
> collapsible Dob),
> as well as in an Orion (an older 8" Dob). In both cases, a little spur (or
> something) on
> the rocker box "bucket" had cut a little groove in the Alt bearing.

Interesting.

I think Teflon pads and alt-bearing laminate ("formica") are the most
frequently worn out items on Dobsonians. So far, I have had to replace
formica on the alt bearings of the 17.5" Discovery (did it before the
Dec 2013 Coorg event), as well as re-glue broken formica pieces on my
18"; and even yet, the formica on my 18" doesn't want to stay, so I
have tape holding it at the edge on the bearing. And I've had to
re-glue the teflon pads on my 18" a number of times; and I frequently
find myself sanding them.

> I was even toying with the possibility that the boxes for both were made by
>
> the same
> manufacturer before I realized that the scopes were not of the same
> vintage.
>
> That apart, I've read enough accounts of people complaining about how their
>
> large
> Dobs just out of the box were so unbalanced that a slightly heavy eyepiece
> would
> send the OTA slewing hurriedly towards the ground :)

This is very bad. The problem with dobs is that the friction has to be
"just the right amount" to keep the motion smooth, yet keep it
balanced for a wide range of eyepieces (that may weigh anywhere from
1.2kg to less than 40g) and not make the friction too less so that the
telescope will move due to the slightest breeze. The stiction has to
be low enough to allow for the slightest movement at very high power.
Somehow, it still works.

Also, I think it's normal for large dobs to require some amount of
counterweight when you hang a 1kg eyepiece on the edge. Obsession
sells counterweight rods specifically for this. I had these issues
initially, until either I replaced the Teflon pads, or they wore out a
bit so they are a little less smooth now. I find that a pair of 10x50
binoculars hanging from the finder scope are a handy counterweight to
have, Dilip sir style, so I tend to carry them around.

> No matter what 'scope one buys, I guess one has to be prepared for
> something to
> be at least slightly off-kilter - especially if it's a Dob.

Every time I go observing, in addition to my observing log, which you
may have seen, I also make a "Telescope problems and KStars
complaints" log. This time, the log is particularly long including
"The eyepiece seems to make the sound of something crinkling against
the glass when I shake it", which I fixed today; replace equatorial
platform worm gear set screw etc.

That's why I emphasize that owning a telescope is like owning a
laboratory experiment. The only reason I can maintain my scope well is
because of my laboratory experience.

Regards
Akarsh

[Akarsh Simha]

> Secondly, it would also give you an idea of the mechanical aspects of
> the scope /after/ it's been in use for a while. For example, with Dobs,
> you'll want to see if the motion is too smooth, too sticky, or both.
>
> The 'both' could manifest itself as the Dob being sticky up to a bit,
> and then suddenly becoming smooth, resulting in you overshooting
> the target when attempting to track. This, IMHO, is worse than the
> action being too sticky or too smooth. It is also an indicator of the
> build quality not being very good.

Isn't this simple to fix? Replace / sand Teflon pads, and set the
tensioning springs appropriately (for small dobs)? I don't know if any
magic went into Obsession's builds, but they are very nice. It's
probably all in Kriege's book, so it might be worth looking at.

Regards
Akarsh

[Acis Ace]

Well, 25,000 is the practical maximum of my budget (Which was previously 20,000).

Now it seems Skywatcher is the only brand that many customers have been comfortable with.

I PMed Sathya sir and he notified me about 2 telescopes of which one is the 6" dobsonian from skywatcher you people are hell bent upon :)

I think I will go with it then.

The total cost (excl. shipping) will be a little out of my budget but I think I will be able to get it funded when I will come to Bangalore in May (Which also means zero shipping cost).

Thank you people.

On a lighter note,

Sathya sir, do you speak Hindi ? :P

PS. Anyone have any idea how to transport the dobsonian by plane or train (without gaining unwanted attention)? 

[Akarsh Simha]

> PS. Anyone have any idea how to transport the dobsonian by plane or train
> (without gaining unwanted attention)?

In the past, I've taken it in buses and trains in: a) cricket bags, b) as is.

Regards
Akarsh

[Srinivasan S]

Any advise on the best shop / vendor in Bangalore to buy this telescope?

[Anish Kumar]

Remove the primary mirror cell and take it as carry on, if going by plane. I wouldn't trust the baggage handlers.

[sathya kumar Prasanna]

Aces ace, I do speak Hindi.

Karthik et al You guys will be surprised to know that Dobs now have eliminated the use of Teflon azimuth bearings completely. They now use Metal disks with small Roller bearings (many of them) which looks like a gramophone disk. This completely eliminates the sticky problem and any such stickyness is resolved by loosening the pivot bolt.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

[sathya kumar Prasanna]

Srinivasan, I supply the Sky-watcher brand telescopes, but I do not stock them in Bangalore. If you want to purchase one, please send me a personal message.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com

[Akarsh Simha]

Dear Aces Ace

I think you are better off buying the telescope in Bangalore, if at
all. Bangalore has a good community of observers (including a small
astronomy club at IISc if I'm not mistaken), and they have telescopes.
If you have never done astronomy before, it is generally recommended
that you first look through someone else's telescope and get
sufficiently familiar with it to let them let you use it, and then use
it yourself for a bit. That's when I'd say you'll be completely
knowledgeable to make a telescope purchase. At this point, I'd say
it's a good idea to defer your purchase.

In the meantime, if you've not yet already done so, you would be well
advised to learn the constellations, visit a dark sky site, do some
naked-eye observing (eg: Beehive cluster, Orion nebula) or borrow a
pair of binoculars from a friend for a lot of mileage.
Regards
Akarsh

2016-04-05 23:36 GMT-05:00, sathya kumar Prasanna <skps...@gmail.com>:
> Aces ace, I do speak Hindi.
> Karthik et al You guys will be surprised to know that Dobs now have
> eliminated the use of Teflon azimuth bearings completely. They now use
> Metal disks with small Roller bearings (many of them) which looks like a
> gramophone disk. This completely eliminates the sticky problem and any such
> stickyness is resolved by loosening the pivot bolt.
>
> Thanks and Regards
> Mr. Sathyakumar Sharma,
> Scientific Officer,
> Karnataka Science and Technology Promotion Society,
> DST, Govt of Karnataka,
> Banashankari 2nd Stage,
> Bangalore.
>
> Phone: +91 8095626184

> http:/ <https://www.facebook.com/SathyakumarSharma>/
> sharma-astronomy.weebly.com

[Karthik Subramanian]

On Wednesday, 6 April 2016 09:04:49 UTC+5:30, Acis Ace wrote:

Now it seems Skywatcher is the only brand that many customers have been comfortable with.

I PMed Sathya sir and he notified me about 2 telescopes of which one is the 6" dobsonian from skywatcher you people are hell bent upon :)

I think I will go with it then.

Hi Bhaskar,

Just wanted to call this out - please don't get the impression that anybody

is hell-bent on a particular brand (or hell-bent /against/ a particular brand).

If you've decided to go with a certain brand, good for you (and the brand).

Please do understand that the decision is ultimately yours :)

K. 

[keerthi kiran]

Hello Bhaskar,

As Akarsh said, you should buy the telescope after you shift to Bangalore. Before you make the purchase, please see through the telescope and decide whether that is what you want. In Bangalore, many people have telescopes and you could go out with one of us and see through the telescope.

Thanks and Regards,

Keerthi

[Karthik Subramanian]

On Wednesday, 6 April 2016 10:48:30 UTC+5:30, sathya kumar Prasanna wrote:

Karthik et al You guys will be surprised to know that Dobs now have eliminated the

use of Teflon azimuth bearings completely. They now use Metal disks with small

Roller bearings (many of them) which looks like a gramophone disk. This completely

eliminates the sticky problem and any such stickyness is resolved by loosening the

pivot bolt.

That's nice :) This is indeed a welcome development!

I wish something similar would happen with the Alt bearing as well :D

K. 

 

[Akarsh Simha]

>> Karthik et al You guys will be surprised to know that Dobs now have
>> eliminated the
>>
> use of Teflon azimuth bearings completely. They now use Metal disks with
>> small
>>
> Roller bearings (many of them) which looks like a gramophone disk. This
>> completely
>>
> eliminates the sticky problem and any such stickyness is resolved by
>> loosening the
>>
> pivot bolt.

This has its own share of issues though. The teflon pads are very
user-servicable. The roller bearings seem like they will be more of an
issue; for example, getting the right diameter and length etc might be
anon-trivial task.

I really enjoy the fact that most astronomy equipment is
user-servicable. The fact that I could take apart my equatorial
platform, replace the power source with USB; take apart a precious
TeleVue Delos to fix a loose retainer ring and put it back together;
etc. saves a lot of money.

Regards
Akarsh

[sathya kumar Prasanna]

Roller bearings by design are for carrying loads. Given that there are over 20 of them in an 8" diameter disk I doubt very much if they require any maintenance at all. 

In the worst case scenario, yes, you are correct. They are very hard to replace. But then, the telescope itself  would have to be banged up really bad for the bearing to give way.

Thanks and Regards

Mr. Sathyakumar Sharma,

Scientific Officer,

Karnataka Science and Technology Promotion Society,

DST, Govt of Karnataka,

Banashankari 2nd Stage,

Bangalore.

 
Phone: +91 8095626184

http://sharma-astronomy.weebly.com