Stargazing Planning to buy a first telescope? - Comments

sophiecentaur

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A good tripod is probably the best incremental value if you have a good pair of binos. Nearly all of them have a fixing hole for a cheap adaptor.
Choice of telescope depends on your money, your strength, transport situation and suitability if your garden.
Don't even consider the rubbish that's on sale in non-specialist stores. Ugh- nasty.
Read a lot of different opinions before choosing. Your personal formula is very important.
I thought a lot before my choice and no regrets (for me). I got an 8" Newtonian (Dobson mount) which will (they tell me) allow me to see loads of stuff. Still waiting for right conditions and my learning process.
 

sophiecentaur

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if you have a good pair of binos
Canon make a range of extremely sexy image stabilised binoculars. Big / small and high/ low magnification. The only trouble is that they will set you back nearly 1kGBP which could buy you a fairly respectable s/h telescope and mount. But bins are good for much more than stargazing. More decisions. . . . . .
 
my first telescope was a celestron equatorial 114 powerseeker id go with that its around 130 i think
 
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I've been thinking about getting a telescope for years, and I have finally done so!
I decided to go for a very cheap entry level scope, since I wanted to get a feel for the craft before I go for better stuff (which I very well may do).

I am a little embarrassed to share the specifications here since it's probably a comparatively shoddy piece of equipment, but anyway:

It's a 70 mm refracting telescope with a focal length of 300 mm, and it came with two eyepieces, one Barlow lens, one erecting eyepiece, moon filter and a mount. I paid merely $35 for it :smile: (link to the telescope is here).

First impression: I actually managed to assemble it without the instructions. I looked at the Moon the other night and was very pleased with what I saw; for the first time I clearly saw with my own eyes surface details, craters etc. It was quite a moment for me, I have to say.
Magnification with the various accessories is from 15x up to 150x. Later I will try to fit a camera to it.

The mount is not very good, and neither is the stability, but what can I expect for $35?
A small cost for a man, a giant leap for my eyes! :biggrin: Maybe I will post Moon photos on PF later...
 
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sophiecentaur

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I clearly saw with my own eyes surface details, craters etc.
A brilliant experience!! Take a look at Jupiter, too. It's pretty visible at this time of year. Those moons will blow your socks off although you may not see any detail of Jupiter's actual surface. Impress your friends too!
Unfortunately for you , it's the beginning of a slippery slope and you will need to be strong to avoid limiting your spending to a sensible level. Food and new shoes for you (and the kids?) are actually a priority. :wink:
 

davenn

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I've been thinking about getting a telescope for years, and I have finally done so!
awesome, Dennis

As Sophie said, it's the beginning of a long and slippery slope as aperture fever sets in and the bank account starts to feel the strain :biggrin:

a solid mount ius very important and if you find the optics are not too bad, then it may be worthwhile investing in a better mount
to stabilise the unit in a better way

If you haven't already, don't forget to download Stellarium
http://www.stellarium.org/

and then start to learn to star hop around the sky to find objects




Dave
 
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Thanks, Dave!
As Sophie said, it's the beginning of a long and slippery slope as aperture fever sets in and the bank account starts to feel the strain :biggrin:
Yes, I've heard that telescopes and astrophotography can be quite addictive... a fun thing is that I've got a shopping list of accessories to get (e.g. better eyepieces, barlows, various filters, camera adapter, finderscope) and the cost of the accessories I plan to buy are about 3 times the cost of the telescope I bought...:smile: but the accessories will be useful for a possible future new telescope, so I don't mind.
a solid mount is very important and if you find the optics are not too bad, then it may be worthwhile investing in a better mount to stabilise the unit in a better way
Thanks, I will definitely consider that. I realized the importance of a good mount very, very quickly with my shoddy mount :biggrin: The last time I checked the Moon with my bare eyes it did not bounce up and down or back and forth... :smile: If I upgrade in the future I plan to get a scope with a motorized mount, since I'd very much like to be able to take long exposure photos.
If you haven't already, don't forget to download Stellarium http://www.stellarium.org/
Done :smile:.
 

Drakkith

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If I upgrade in the future I plan to get a scope with a motorized mount, since I'd very much like to be able to take long exposure photos.
Just make sure the mount you get is a good one. Wait the extra month or three if you need to save up more. Trust me, it's worth it. You do not want a so-so mount when doing astrophotography...

Same goes for the rest of the gear too I suppose. I bought some used equipment and have been plagued with equipment problems ever since. :frown:
 
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If I upgrade in the future I plan to get a scope with a motorized mount, since I'd very much like to be able to take long exposure photos.
But I should add that I am aware of the photostacking option too, of course, as the youtuber Forrest Tanaka describes in this video from beginning to end:

Astrophotography without a star tracker

He had a tutorial also on telescope guiding. I've watched all his tutorials, I post them here for others who may be interested:

Astrophotography P1: Telescope OTAs
Astrophotography P2: Choosing & Using Telescope Mounts
Astrophotography P3: Guiding Your Telescope

and here is his youtube channel: http://www.youtube.com/user/ForrestTanaka/videos
 

jim hardy

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Dad built an equatorial mount from plumbing fittings. A 2 inch Side Outlet Tee makes for sturdy leg mounts.

SideOutketTee.jpg


will post a photo if i can find one.

equatorialbase.jpg
 

Vanadium 50

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but what can I expect for $35?
The instructions are a hoot! "After find out the big goal, then debug with different eyepieces." And "if the window is big, the natural light is good, and the view is clear" sounds like a password between secret agents.

I think I agree with you - your next purchase should be a good mount. No matter what you look at, a good mount will help, while the optics will depend on what exactly you want to be looking at.
 
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The instructions are a hoot!
I've bought quite a lot of items from China and had many good laughs reading "Chinese English" instructions... some have been almost impossible to decode. And this is a fun picture I remembered from an article about a small video camera (which I did not buy, though).
 
Hi everyone! I have one question:) I got interested in astronomy and cosmology so that my husband wants to buy a present for me and I'm not sure which telescope to choose...
 

jim hardy

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I've never spent much time with a telescope, so my knowledge is pretty limited. I've spent a few hours over my lifetime, looking at the heavens through the lens of someone else's equipment, but that really doesn't count for much, when it comes to actually learning about the equipment.

A few years ago, I acquired this (old?) telescope and wooden tripod in a bundle of other things at auction. I'm preparing for the Solar Eclipse in August, and I'd love to use this telescope to watch it. When I went to use it, I quickly realized that there were no clear eye lenses - only "blacked-out" lenses. The problem is, since I know my knowledge of telescopes is almost non-existent, I am not certain if the lenses are OK for solar-gazing. I mean, I can not imagine any other purpose for black-out lenses, but what would I know?, ya know? They say "SUN Japan" on them, but I think that's a brand name? There do not appear to be any model numbers on them, although there are some measurements listed on one end of each lens - 6mm, and 20mm. The diameter of the eye piece, where it fits into the angled telescope piece, appears to be about 25mm - but I am having a hard time measuring it with the tools on hand, so I might be off a few mm. (Is that a standard for sizing eye-pieces? If so, I am in trouble, because I don't see anything on Amazon that's even close...)

The telescope appears to be of the brand "Focal", made in Japan. It also says: "Astronomical Telescope F=700mm D=60mm", and also "code no. 20-20-66".

It looks similar to this telescope: https://www.ebth.com/items/6190881-scope-telescope-with-tripod mine is orange, however. I think this may have been a K-Mart purchase for the original owner, as I am seeing several (outside) forum posts that would indicate it. It's clear to me that this is not a high quality optical instrument, but rather, more of a toy. Still, it will do for a starter telescope, and if I get excited about the sport, I will consider upgrading in the future.

I have images of my telescope I would like to add, but apparently I lack the intuition to understand the interface in order to do so. Perhaps adding pictures is only allowed for paying members of the forums?

I am just starting to research this telescope, and, among other things, will be looking for clear lenses, so I can watch planets this winter, when skies are crystal clear at night. Please forgive me if I have left out any pertinent information. I'll be more than happy to provide anything that I can find, if you tell me what to look for.

Any assistance you can offer to help me get this scope "Eclipse Ready" in the next few weeks will be most appreciated, and if anyone has a favorite source for buying eye pieces that will fit this telescope, I would love to hear about it. In the meantime, I will be blindly searching eBay, Amazon, and Google, while I try to figure out what I have, and what lenses I am looking for to fit it...

Thanks
 
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jim hardy

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Is that a standard for sizing eye-pieces?
I think one inch is standard , 25.4 mm. OOPS TIL it's 0.965 inch, as Dennis pointed out below.

I've never seen "blacked out" eyepieces.

if anyone has a favorite source for buying eye pieces that will fit this telescope,
Are you handy with small hand tools?
Old film cameras are literally a buck or two in thrift shops. I take them apart for the lens which i can put in a PVC pipe fitting or old sewing thread spool and sand down to 1 inch..
Standard focal length is about 35 to 50 mm, wide angle is shorter. I have a zoom lens out of a fancy little Canon that should be fun but have yet to mount it


"Focal" was an inexpensive department store brand. It'll do the job of getting you started.
Its objective lens(the big one) is 60mm diameter, its focal length is 700 mm, .
magnification is (focal length of objective) / (focal length of eyepiece)
so your 6 mm eyepiece gives 700/6 = 117 X which is completely unusable on a cheap tripod because you can't keep it still let alone aim it.. But power sells.
Your 20mm gives 700/20 = 35 X way more useable and great for moon and Jupiter, it'll show Saturn's rings.
A 35 from a thrown away camera will give 20X great for the moon.

Eclipse ?
I'd say use your telescope to project an image of the sun onto another surface, as in this article

http://www.skyandtelescope.com/astronomy-news/how-to-look-at-the-sun/
 
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@jim hardy

By "Blacked out", I guess I mean they look like the lenses used in welding goggles. The glass is very dark, nearly black.

That article is interesting, but my eyepiece is at a 90 degree angle (perpendicular) to the barrel of the telescope. I suppose I could try to set up a screen off to one side, but I don't see me traveling 8 hours to Makanda, Ill, and then having the patience to set something like that up when I get there. I'll have to think about it - maybe I can come up with something small and simple, that will travel well. I still have 7 weeks to get creative.

Please explain how the PVC pipe, or sewing thread spool helps you grind down the lenses? It sounds like you may know a useful trick that I'd like to learn more about.

THANKS!
 

jim hardy

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Please explain how the PVC pipe, or sewing thread spool helps you grind down the lenses? It sounds like you may know a useful trick that I'd like to learn more about.
No, no you use the lens as is.
the lens out of those "point & shoot" cameras (thrift shops are full of them)
upload_2017-6-25_16-27-15.png


is about 3/8 inch diameter . Cheap ones are plastic better ones glass.
I put it in something that i can sand to fit into the telescope eyepiece holder.

Sorry for the confusion.

old jim
 

DarioC

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I have a question about my Celestron 130EQ reflector. Previously I had a 70mm refractor and I remember being astounded at the sharpness and contrast of edge on views of the ridges on the moon that it gave. The 130 pulls in a lot more light; it is uncomfortably bright when looking at a full moon with the scope unrestricted but it's images don't seem to be nearly as well focused as the 70mm was at what I think is about the same magnification.

Makes me wonder what the process for making the 5 inch mirror is, but thus far I haven't really checked close enough to actually tell. Everything about the 130 is well made and works good, but I am a bit disappointed about the blurriness of the view.

DC
 
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Hi, Blank_Stare, I'm a telescope beginner, but I have learned more about it recently...

There do not appear to be any model numbers on them, although there are some measurements listed on one end of each lens - 6mm, and 20mm. The diameter of the eye piece, where it fits into the angled telescope piece, appears to be about 25mm - but I am having a hard time measuring it with the tools on hand, so I might be off a few mm. (Is that a standard for sizing eye-pieces? If so, I am in trouble, because I don't see anything on Amazon that's even close...)
6mm, and 20mm
These seem to be the focal lengths of the eyepieces as jim hardy explained above, see also http://en.wikipedia.org/wiki/Eyepiece#Focal_length.

The diameter of the eye piece, where it fits into the angled telescope piece, appears to be about 25mm
There are different diameter standards, and yours seems to be 0.965 inches (24.5 mm), see http://en.wikipedia.org/wiki/Eyepiece#Barrel_diameter.

I recently bought a cheap entry level scope with the same eyepiece diameter as yours, and since I have planned to try to photograph the Sun, I have bought some accessories for this, I list some of them here as examples:

Adapter which enables use of 1.25 inch (31.7mm) eyepieces and filters for telescopes built for 0.965 inch (24.5mm) eyepieces:

Solar filters that can be placed in front of the telescope (note: three diameters, check product description):
Various filters:
Camera mount:

But please note:
  1. Watching the Sun without proper eye protection is dangerous and can damage your eyes, as explained in the article jim hardy posted above.
  2. I can't vouch for the filters I listed above, since I have not tried them yet
  3. The item links from me above are from AliExpress which have delivery times of ca 30-60 days
but my eyepiece is at a 90 degree angle (perpendicular) to the barrel of the telescope
I guess you mean there is a star diagonal mounted between the telescope tube and the eyepiece, see http://en.wikipedia.org/wiki/Star_diagonal. Check your telescope if you can unmount that piece if you for some reason would like to, and mount an eyepiece directly to the telescope tube.
 

DarioC

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Jim, I thought just recently that I might try a simple check on the adjustment. Just turn one of the three main mirror screws 1/4 turn and then check if a ground image is clearer. Then return that adjustment back and do the same to the next adjusting screw. Any improvement would tell me I should realign the main mirror. As for the second mirror up front, I have read the manual and will have to work on that a bit to devise something or get the correct tool.
 

jim hardy

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I thought just recently that I might try a simple check on the adjustment. Just turn one of the three main mirror screws 1/4 turn and then check if a ground image is clearer.
Go in loosen direction first? So as to not squeeze mirror.?
I think you'll do best at night looking at a star. When mine is out instead of a point they look like a teardrop.

I'm still very much a novice at alignment. I find diagonal mirror way more difficult.
Hopefully an 'old hand' will chime in.
 

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