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Magnores
2010-Oct-28, 07:26 AM
i am an beginner an want to study object as far as saturn.and i am interested in astrophotography which telescope is best for me.and i want to buy that in chennai and where can i buy it





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RickJ
2010-Oct-28, 07:21 PM
There are many astronomy clubs in the St. Louis area. Search them out and attend there star parties. There you will learn far more with hands on experience as to what telescope is best for you in your sky conditions.
http://slasonline.org/ See they have one scheduled for Nov. 10th.

Rick

KatieRowe
2010-Nov-29, 06:04 PM
Sorry I ask similar question but my friend want to sell Celestron Nexstar 130 SLT Telescope for 200 pounds. I always was interested in astronomy but... you know how it is. And now I have such opportunity. Do you think this is a good deal for start?
Price in UK:
http://www.harrisontelescopes.co.uk/acatalog/Celestron_NexStar_130_SLT_Telescope.html Brochure printing (http://www.mixam.co.uk/products/brochure-printing)

RickJ
2010-Nov-29, 07:41 PM
Here in the US that 200 pound price is the same as the new price so not a good deal. I have no idea what the new price is on your side of the ocean. From what I hear all scopes cost more over there for some reason, tariff's probably.

For 27 years I was a supervisor of a public observatory. We saw hundreds of beginners bring their new scopes to us for help using them. Those with computerized scopes comprised about one third the scope sales in our town from talking with the merchants that sold scopes (only a couple) yet they accounted for nearly 100% of our "lost in space" beginners. If you can figure out complex remote controls you may be able to handle them, if not they can be a source of complete frustration. Batteries quickly die in cold weather. Be sure you have a AC supply or you will go through as much in batteries in a year or two as the scope costs. Most ended up in closets we found.

We found the 6" or 8" Dobsonian mounted reflectors (f/8 for 6" f/6 for 8") were by far the best accepted by beginners. Very few ever needed our help. Then it was for advice on collimation or minor issue for all reflectors, including the one you ask about.

Before you buy it be sure to try it out and know you can run it and that it will give you a view of objects like you want. It is more limited due to its smaller aperture than the Dobsonian mounted reflectors we usually recommend. Over here a 6" Dobsonian mounted reflector sells for about the equivalent of 200 pounds (assuming $1.60 a pound) and gives a sharper, brighter view but doesn't attempt to move to the object. It expects you to learn the sky and do your own pointing. For another 75 pounds or so you can add a computer system that's much easier to use than those on the scope you ask about. Again you do the pushing, it tells you how to push it to find the object. I find most beginners do better with these than the motorized ones. The batteries last months instead of hours as well. Keep in mind a good portion of the cost of a computerized scope is for that computer, gears and motors needed to point it with high enough accuracy the object is in the field of view. This means optics have to be far cheaper than in a scope of similar cost without a computer system. So they will be limited in what they can do and show you compared to a similar costing scope without the computer system. Depends on what you want to pay for.

Rick

astromark
2010-Nov-30, 08:25 AM
Like Rick I help at the local Observatory... and would say his advice is sound. Take it.
Do seek out a group or club and a local astronomical society...
The best telescope to buy... is the one that's easy to use... and bigger is not best.

nightmarepatrol
2010-Dec-03, 12:48 AM
I too am looking to buy a scope for my wife for Christmas. The dilema is of course what scope to get. The breaking point on the scope needs to be around $800 or under. I have looked at a few scopes online and spoke to one person I work with (who stated that celestron now makes consistently good scopes).

I am looking for a scope for a first timer (my wife) who is a quick study and is not overly technically challenged. I have been looking at the Celestron SE6. My question is what quality other scopes are in the $800 price range that may be better without requiring a lot of knowledge to get up and running? We currently live in the gulf coast of Florida (north of Tampa) where the conditions are fair to good most of the year. The nearest club is about a 2 hour drive and I can't disappear that long without a really good explanation.

Any input would be appreciated.

Thanks,

- NP -

nightmarepatrol
2010-Dec-04, 12:56 AM
Anybody?

If I still lived in the greatland I'd be trying to take a moderator here to the Marx Brothers for dinner to get advice. The scope "hint" got dropped again tonight as she was standing outside with her monocular.

Anyhow, just looking for an outstanding scope for a beginner for around $800.

nightmarepatrol
2010-Dec-04, 01:13 PM
I've been looking at a variety of scopes lately. The "hint" about a scope was dropped again last night by my wife. I've been looking at the Dobsonians, Schmidt-Cassegrain and Maksutov-Cassegrain types. Portability is important since we live near a large park that has some very dark areas but it must work in a mildly light polluted environment. From reading here it seems everyone is somewhat opposed to computer controlled mounts for beginners though I'm not entirely sure why nor am I convinced it's an entirely bad thing.

If I still lived in the greatland I'd be trying to taking Brett to the Marx Brothers to get his perspective on this. But...like and idiot I moved years ago.

Anyhow... any feedback would be appreciated.

Thanks,

- NP -

RickJ
2010-Dec-04, 09:52 PM
Christmas scopes usually end up in closets because the recipient doesn't have the knowledge needed to use them. You don't say if she already knows her way around the sky. If not that comes first. Without it you are just wasting your money no matter how "good" the scope and how much money you spend.

Beginners should start with a good pair of 10x50 binoculars, a book like this one http://www.philharrington.net/sw8.htm, a star atlas, a red LED flashlight to read the atlas in the dark and maybe a book like "Turn Left at Orion" which does a great job of teaching the sky. This along with an IOU for a telescope might be the best way to go.

While computer scopes can be good for the experienced observer they can be very frustrating for beginners. Nearly all the beginners buying them showed up at the public observatory where I was a supervisor for 27 years asking, pleading really, for help. They just couldn't get them to work. In fact we only had one volunteer who understood them well enough to help all that came in. Most of us could figure out one or two but not all as they worked differently. Many returned week after week as they could get them to work with help but when they got home were again "lost in space". Those very tech minded could make them work without problems. These were the minority.

Even if you can get them to work you have to know the sky well enought to find the setup stars it asks you to find. If you don't know the sky well enough to either know them or at least read a chart to find them a computer scope like the one you mention is rather useless. Even if you do it is 10 minutes or longer before you are ready to observe. This is after fitting it to the tripod in the dark and with gloves on. Then there's the small buttons to work in gloves. Mittens are best for cold winters but useless pushing those tiny buttons. Batteries die very fast in cold meaning AC adapters are necessary. Even in warm climates battery costs mount rapidly without an adapter. At our star parties the cries "Anyone have D cells" or similar are a constant drone it seems.

A manual Dobsonian mounted reflector is easy to set up with mittons, just drop the rocker box and drop in the tube assembly and you are ready to observer. Seconds not 15 minutes. Mount is steadier as well and cost less than half for the same image quality. Carrying a tripod and Cassegrain to an observing site I find harder than the lighter rocker box and tube assembly. Though the longer tube takes more room in a car. Keep in mind if your weather is at all humid the corrector of a SCT or Mak scope or lens of a refractor will dew or frost over quickly without protection. In mildly humid weather a dew shield is sufficient. Where I live dew heaters are needed as well. Not an issue with a Newtonian.

Too bad you find a club too far away. The learning curve of astronomy is steep, nearly vertical it seems at times. A club greatly reduces the climb. They may have members that do travel from your area. Would be well worth checking out. Seems many think this is a hobby that's easy to do alone. In fact it's just the opposite. I spun my wheels for 6 years then found others in my area doing the same and we formed a club. One of the founders went on to be rather well known. He is Dr. Peter Schultz, the guy who punched a hole in Comet Temple 1. Another of our members headed the optical team designing the two 8 meter Gemini Scopes and now is heading up the 30 meter telescope design team. Both say they'd never be where they are without the club's help, the club they helped form and build. This book covers this https://www.lulu.com/commerce/index.php?fBuyContent=8434287 Like some other clubs we have loaner scopes for beginners to rather advanced users while they are learning enough to buy their own. Something else to look into. Even if they don't members often do. I have several I've loaned out this way before our club could afford to do it. I also sold gear at bargain prices to needy young members with potential. All have proven me right too.

Rick

nightmarepatrol
2010-Dec-04, 11:19 PM
Thank you Rick,

Binoculars may be in fact a better choice all things considered. I don't live in Alaska any more (moment of insanity) and now reside in Florida. Dew is a big issue in the gulf area. I would not buy a computer scope that does not have an AC adapter. We have a several hundred feet of extension cords and a small gas generator that will run over 10 hours on a gallon of gas and is fairly quiet.

Anyhow, back to the binoculars. I checked out the Orion Giant View 20x80 (http://www.skiesunlimited.net/index.php?ProductID=2188), Zhumell Tachyon 25x100 (http://www.binoculars.com/binoculars/astronomy-binoculars/tachyon25x100astronomicalbinocularwlockingaluminum case.cfm) and a few others. Obviously I want something that will gather as much light as possible and provide a decent field of vision. The Pentax pair I have here just isn't enough to see any detail which is what she would like to see.

We have a number of tripods around the house so provided the binculars take the same mounting as video equipment we should be good there.

So there...I'm taking direction! Although I'm probably in the minority.

So any comments on on the glasses I picked out? Any recommended filters to get with the glasses?

Thanks.

- NP -

nightmarepatrol
2010-Dec-05, 03:35 PM
After doing a little more investigation I think the Zhumell's are not a great choice. The price is nice, but I'm still a tad iffy on Chinese quality. I'm now looking into the Oberwerk's or other American, Japanese or German manufacturers. Call me picky I guess.

RickJ
2010-Dec-05, 07:26 PM
Note I said 10x50. I did not mention larger ones on purpose. They are NOT a starting point.

Rick

nightmarepatrol
2010-Dec-05, 10:34 PM
There are already a pair of pentax 8x50's in the house which I think will be suitable with a book and a copy of stellarium. problem is my wife wants to see "more." Perhaps the new glasses used in conjunction with the 8x50's will ease that a bit while she familiarizes herself with the sky.

I'm not discounting what you say at all, but understand I'm trying to fill a need without overfilling it.

astromark
2010-Dec-05, 11:23 PM
When you look at the ease of use and power and light gathering potential the binoculars win, hands down. But....
and there is always one or two... if you get into a too larger size then a tripod becomes essential... Now you should have bought the telescope.
The modern 'Dobi' is both convenient and light and powerful. But still requires some effort to set up... Going bigger than a 12 inch would be a mistake. The advise given about the 10x50's is sound in regard to bino's. Always will be the most used tool...
Just as the larger telescopes require larger mounts or they are useless.. the same rule applies to bino's. Yes the 25x 100 can give you good astronomy images. Clumsy springs to mind... and finding a tripod or parallelogram thing that will hold them still... I use a broom. it works., but I use 10x 50's... and after 35 years still do.
If you still feel the want for a bigger power then yes the 'Dobi' telescope is the way forward. Cradled mounts might be manual but are still best.
Best is both convenient and useful... its always a compromise. You can not afford the Keck observatories 10.2 metre scope. nor would it fit on your lawn....:wall::razz:

redshifter
2010-Dec-07, 07:55 AM
I have 8X42, 12X60, 15X70, and 25X100 binocs. The 25X100's are great, but definitely not what I would call a 'beginner' type binoc. I spent more on a stable, heavy duty mount than the binocs themselves, and a heavy surveyor type tripod. It works quite well, and the 25X100's are completely useless without it. They weigh 10lbs and have ~3 degree field of view--no way can anyone hold them remotely steady for any length of time. Just FYI if you're serious about any binocs over 50mm objective--be prepared to spend more $ for a stable mount, it is essential.

Your 8X50's will do nicely for just about any binocular object, and probably don't require a tripod for stable viewing. Take your time, use your binocs, and learn the sky. Then you'll be ready for a scope.

nightmarepatrol
2010-Dec-11, 12:36 AM
Yes I'm back. The 8x50's are working out well to this point. However the obvious desire for more light gathering is there. Since my wife also wants to look at some terrestrial objects or near terrestrial at long distance. (ie aircraft) as well as getting accustomed to the sky I've narrowed it down to two high powered binoculars. The Oberwerk 25x100's IF's and the Gemini 25x100 WP-IF Mk II's. From what I have read the Garrett's seem to be a better bet for not much more money. Yes for the price I know could buy a nice little Dobsonian, but The binoculars a going to be more practical at this time I think.

So any opinions on the Oberwerk's versus the Garrett's?

Thanks.

- NP -

RickJ
2010-Dec-11, 08:18 AM
100mm binoculars are only for the experienced user. NOT A BEGINNER. They are very difficult to use. Redshifter tried to tell you this but you weren't listening so I'll up the decibel level.

For this a spotting telescope is far better. Light and works on a simple tripod that can't carry heavy binoculars. Those binoculars are virtually impossible to hand hold for more than a few seconds and impossible to focus that way. You have to have them on a good support. It will cost more than the binoculars if you do it right. Many require special chairs as well. You will find them exceedingly difficult to point as well, no finder scope to help. The field of view will be only 8/25^2, about 10%, as big in area seen given similar design. Finding that moving plane will be nearly impossible. Note too the exit pupil is 4 mm both of these. The 8x50's have a 6mm exit pupil. This means the image is BRIGHTER in the 8x50's. Counter intuitive but true. You've increased the power 25/8=3.125x and thus spread the light out over 3.125x3.125=9.76 times. But the front lenses are only 2.5 times larger so gather 6.25x the light. Spread that over more than 6.25x the area and you get a dimmer image not a brighter one. In fact it will be only about 44% as bright per unit of area. Nebula will be bigger but dimmer.

Be sure to try anything out before you buy. You will find it very different from your expectations.

I won't get into which brand is best as in nearly 60 years in this hobby I've never found it useful to go beyond my 10x50 binoculars. Yes I've used binoculars of that size and I've used far larger, up to 25x150. They needed a 75 pound tripod and weighed nearly as much, taken from a Japanese pillbox in WWII.

Get a spotting scope for terrestrial viewing (60mm is fine as daytime seeing rarely supports a larger aperture nor does the eye's pupil open in daylight sufficiently to use even that much aperture) and use the binoculars to learn the sky so you are ready for a real telescope. I've seen well over 100 deep sky objects in my 10x50 binoculars, Planetary nebula like the so called "Eye of God", Supernova remnants such as the Veil complex and M1, galaxies, nebula and star clusters simply with those simple binoculars because I know my way around the sky. You don't. Getting bigger binoculars won't help, just make it more difficult in fact. 12x60's is about as large as I'd go as a beginner if you just have to have more power. They won't be as "bright" as your 8x50's but will show a bigger image and you still have a chance to find what you are looking for.

Rick

nightmarepatrol
2010-Dec-29, 09:02 PM
Well the deed is done. I ended up purchasing a pair of the Garrett 25x100 Mark II IF binoculars with a tripod and the Multiple Reticle Reflex Finder / Sight, all from Garrett. We started out in the day doing simple things like getting the finder situated on ground based objects and familiarizing ourselves with the tripod and binoculars . I figured that would be better than trying to fumble around and learn in the dark. Jupiter was the easiest target to find and we could observe the planet as well as four (possibly five, but we need more views to determine that I think.) I think I also found M15 last night as well.
The views have been spectacular so far. If I were qualified to write a review on these I would be more than happy to do so. I know that a few of you urged me not to go this large but learning is a process and we will learn given time, reading and clear skies.

Thanks again for all the input even If I didn't listen.

Bet you thought you'd never hear from me again either did you?

Glom
2011-Jan-04, 08:28 PM
I'm off! My 842 binoculars are still around and in great condition. But maybe I should get a scope. It would only be for easy viewing: Moon, planets etc. Nothing fancy. I'm thinking something like a 70mm refractor? Maybe a 3". It shouldn't be too awkward to haul around so I can take it nearby. I won't bother with an equatorial mount either. I could never get the damn thing to work right, although even a coarse alignment did making manual tracking a tad easier. I always say I'd like to do some prime focus photography, but given that my EOS 1000D is bigger than the scope, it probably isn't worth any extra expense to enable that.

An extensive two seconds of googling revealed this (http://www.celestron.com/c3/product.php?CatID=62&ProdID=422). Celestron are still reputable, right? As well as the near space, that will get me a good open cluster and maybe even a nice nebula as well. I see the scope itself is going for $130. 80 isn't too bad, although I do have to buy the eyepiece set separately. It looks nice though I might choose to get something less extravagant.

Glom
2011-Jan-06, 05:55 PM
Am I a ghost? Why does the topic list not say my post was the most recent?

Hornblower
2011-Jan-06, 09:25 PM
Am I a ghost? Why does the topic list not say my post was the most recent?

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