Archive for February, 2010
Where can I buy a telescope without mount and tripod?
I have a good tripod and mount, but would like to upgrade from a 4" to a 6" reflector, so will need a new tube and cradle. What mail order suppliers in the UK sell these on their own please, they all seem to sell complete kits which is annoying if you already have a tripod and mount.
my 4" reflector is a very good Meade model
What you are looking for is called the ‘tube and optics’ which is a term more often applied to refractors but applies equally to all telescopes…refractors, reflectors, and catadioptrics like the Maksutov and SCT designs.
The jump from 4" to 6" is definitely worth doing. It is not a minimal jump as suggested above, but a decent upgrade which will give you much more scope for your observing nights….haha,love that one.
The problem is likely to be the mount.
A 6" is heavier and bigger than a 4" and requires a much sturdier mount.
If you have something comparable to the Eq2 then a 6" will be too much for it. Even an Eq3 or equivalent will be struggling and you won’t be enjoying your sessions nearly as much as with the 4" and you’ll very disappointed. Even a slight breeze can give you big problems with a mount that is too small for the Telescope.
An Eq5 or equivalent is the smallest I would recommend for a 6" telescope.
I use a CG-5, Celestron’s equivalent to the Eq5 for a 6" refractor which is OK on calm nights but with even a fairly moderate breeze I can’t use high powers with it. The telescope does have a long tube and is fairly heavy.
http://www.astronomyboy.com/cg5/ . . . .
You can buy tube rings from Warehouse Express or other outlets, and heavy duty dovetail rails to fit the scope to your mount, assuming it has a standard dovetail fitting.
Otherwise just buy the 2 tube rings and make a bracket to bolt them onto so you can to fit it onto your mount, using aluminium or a hardwood like teak or oak.
My 8" Newtonian has a simple home-made bracket …just a 20" bar of 2×1 teak well varnished, and drilled for 1/4" Whitworth bolts for the tube rings and to fit onto the head of the Fullerscopes Mark 3 mount with drive motor bought very cheaply from a guy who actually had a 10" on it…rather pushing it for stability but the mount can handle a lot of weight for it’s size.
I’m still looking for a Fullerscopes Mark 4 for it. The two are shown together on here…scroll right down for pic, just under the Moon pics
http://fullerscopes.blogspot.com/ . . . .
Warehouse Express is reliable and is one of the cheapest outlets for telescopes and accessories in UK. I have several purchases from them with no problems.
6" tube rings are on here
http://www.warehouseexpress.com/buy-sky-watcher-150mm-tube-ring-set/p10714 . . . .
Here is the accessories page. Look under ’supports’ for rings and mounts
http://www.warehouseexpress.com/category/categorynav.aspx?cat02=2021
Reflecting telescopes on here
http://www.warehouseexpress.com/category/basecategory.aspx?cat03=3013 . . . .new link
Orion Optics UK do some excellent telescopes and are a reliable firm with a well deserved reputation for quality. The American company Orion Telescopes is unrelated and is a very popular outlet for telescopes and binoculars in the USA…second link
http://www.orionoptics.co.uk/ . . . .
http://www.telescope.com/control/main/ . . . . .
Telescope house are the successor to Broadhurst Clarkson and Fuller which used to be Britain’s biggest telescope company, making quality equipment for profressional and amateur astronomers…since 1785.
Although it still has a small manufacturing base for accessories it is nothing like the old firm, which was the byword for astronomical supplies in UK for many generations.
http://www.telescopehouse.com/ . . . . .
The Widescreen Centre is well worth a visit if you are close to London. Visitors are welcome for a chat and a browse, and the staff are excellent. It is a couple of minutes walk from Baker Street tube station and can be highly recommended.
Don’t let the name put you off. It is a respected and well-known part of the telescope scene in UK and it’s photographic and display department is used by profressional photographers and exhibition organisers.
It has built up a good repution amongst profressionals and amateurs in both photographic and exhition work, and in astronomy.
http://www.widescreen-centre.co.uk/ . . . .
In the north the Stockport Binocular and Telescope Centre is very good and worth a visit. I have dealt with them a couple of times and I’m very happy with them. A cute ( in the Russian ‘built like a battleship’ sense) 2 1/2" Tal reflector bought from Stockport for a song and which came on a very solid pier mounting is a display piece in my front room and is surprisingly good optically as all the Tal equipment is.
The Tal-2 6" reflector is probably the best buy for the money available anywhere and is optically superb considering the cost. Even the packaging is miles ahead of the rivals.
The Tal comes in a strong and well-made wooden crate.
My Tal-1 is over twenty years old and like new.
So is the wooden crate.
Tal reviews..the first is a few years old but nothing has changed.
Tal telescopes are consistently rated amongst the best available for the money and out-perform more expensive telescopes both opticlly and mechanically.
http://irwincur.tripod.com/new_page_1.htm . .
http://www.telescopes.ru/product.html?cat=1&prod=8 . . . .
Stockport Binocular and Telescope Centre
http://www.telescopes-binoculars.co.uk/
In February every year Astronomy Now magazine has an awesome exhibition in Kensington High Street, with a large assortment of firms showing telescopes, accessories, and astro-related items.
Astronomical paradise for three days, with a full program of lectures as well. It is well worth the trip to London to attend, for anyone with more than a passing interest in astronomy.
Here is the one held last February, with a video tour
http://www.astronomynow.com/european_astrofest_2009_blog/ . . . . .
Next year’s is on here, looking a bit bleak yet but the event gets bigger every year so no worries.
http://www.astronomynow.com/astrofest/ . . .
Happy nights, dark skies. Without the clouds…fat chance yet! It’s blowing a hooley where I am and lashing it down. Couple hours grinding later. On a big blank pyrex glass disc from Orion Optics. It might be a in telescope in another year or so. Or six months if the weather’s bad. More ‘in’ nights then.
……………EDIT………
You could have have problems putting a 6" on the mount suppplied with your Meade.
You will likely need a heavier counterweight or an additional smaller one to add to the existing one and the mount will be overloaded and unstable.
Meade is a good company selling good telescopes but even they are not going to supply a 4" reflector with a mount suitable for a 6". They’ve got their profit margins to look after like any company.
Unless you specified an upgraded mount with the telescope you would be better to keep the 4" on it’s mount and find a heavier mount for the 6", or make one.
Mounts are not difficult to make and can cost nothing in materials if you look around for good heavy timber in skips and can modify thrown-out items from the tip. Push-along lawn mowers are favourite sources of gear wheels and bearings for example. One of my early acquaintances in astronomy had a 12" home-made telescope in an iron tube on a massive mount for which the polar axis was an entire Ford V8 engine with the valves and rods removed, sunk in half a ton of concrete. The flywheel had a declination axis welded to it. That was a 600cc motor bike engine with a Honda 125 engine for a counterweight.
He said it was the ‘most engineered’ mount he had ever made,haha.
Telescope mounts can be a source of extreme humour for the imagination and lateral thinking involved in their design and construction.
So can the telescopes themselves. Scroll right down to the bottom for a good chuckle
http://starizona.com/acb/basics/equip_telescopes_other.aspx . . . . .
This mount for an 8" is a similar design to the Mount Palomar 200" mount and can be made from scrap for nothing
http://www.bbastrodesigns.com/8inch.jpg
what is the magnification of a telescope with an objective of 4000 mm and an eyepiece of 26 mm?
What is the magnification of a Telescope with an objective of 4000 mm and an eyepiece of 26 mm?
No idea, some pre-lab question, not in textbook, TA said "use the Internet"
4000/26
I wish to buy a telescope, which type would suit me and how expensive would it be?
I want to use it for amateur observation. I am not science student, don’t need it for any academic purpose. Just at home for use at nights sometime.
How much do you think it would cost?
Generally, you should expect to spend at least $300 to get a telescope which isn’t a piece of junk. $300 will get you a basic 6" Dobsonian reflector, which is the minimum I’d recommend. Get a larger aperture, 8" or 10", if you can afford it. There are lots of other designs out there, but years of helping beginners have shown that a small Dob is the best value. Buy from a Telescope store, either local or online, and NOT from Wal-Mart, eBay etc., as all they sell is junk. Forget about goto unless you’ve got a lot of money to spend.