I don’t know what telescope I have

[Replayy]

Dumb question but I was given a telescope but I don’t know what one it is. It has no writing on it at all if you need other angles let me know 

[Cornelius Varley]

Can you provide some dimensions? Tube diameter and length.

[dweller25]

It’s a Newtonian with maybe a 200mm F/6 mirror.

Dimensions as requested above will confirm

Edited April 17 by dweller25

[John]

It looks like one of the Beacon Hill Telescopes newtonians and their standard equatorial mount.

The finder looks like an early Orion Optics one.

Actually, the mount could be an old Orion Optics one as well - they were very similar to the Beacon Hill mounts.

I'd guess that it dates from the 1980's ?

The tripod is a photo one, not an original part. It's not going to do the scope and mount any favours at all in all honesty.

 

Edited April 17 by John

[RobertI]

Looks like the draw tube is missing from the focuser, will need some attention at some point.  

[dweller25]

2 hours ago, RobertI said:

Looks like the draw tube is missing from the focuser, will need some attention at some point.  

I think the draw tube is on the front dust cap for some reason.

[RobertI]

57 minutes ago, dweller25 said:

I think the draw tube is on the front dust cap for some reason.

Ah yes, well spotted. 

[Louis D]

Will probably need a photo down the tube to see if the spider and optics are still there.

[Space Hopper]

There may be more than one spider in there..........🙃

[Replayy]

On 17/04/2024 at 16:57, Cornelius Varley said:

Can you provide some dimensions? Tube diameter and length.

So it’s 106cm length and the end is 23cm.

and when I try and look through the lens it’s really blurry can’t see anything, do any of you know the cause / solution?

Edited April 18 by Replayy

[Replayy]

3 hours ago, Louis D said:

Will probably need a photo down the tube to see if the spider and optics are still there.

Not sure if these are what you mean 😂 I have no clue about telescopes 

[dweller25]

Sounds like an 8” F/5, mirrors look reasonable but hard to tell.

Do you have any eyepieces with it like this - ignore the writing.

Edited April 18 by dweller25

[dweller25]

I just saw an eyepiece - it’s in the end of the draw tube….

[dweller25]

You need to put the above drawtube back into the focuser, marked below..

[Replayy]

Yeah I put the eyepiece in there but the image is really blurry sorry forgot to say I actually put it in.

I put it in and wheeled the sides down and up and nothing seem to get a clear image 

[maw lod qan]

Best to first  try it outside in the daytime. 

Focus on a building or something similar a little distance from you.

Not trying to sound funny, but under no circumstance look at the sun!

With out a proper solar filter eye damage would be irreparable. 

[Replayy]

16 minutes ago, maw lod qan said:

Best to first  try it outside in the daytime. 

Focus on a building or something similar a little distance from you.

Not trying to sound funny, but under no circumstance look at the sun!

With out a proper solar filter eye damage would be irreparable. 

I tried looking at a tree, the sky and a building all blurry, if I took the eyepiece out and look through it should it also still be blurry because it is. Probably dumb questions but I have 0 clue so I really appreciate all the help

[Louis D]

If you look down the tube from the open end, you should see a magnified image of your face like in a shaving mirror when you have your head at the right distance above the end.  It's generally around 6 to 10 inches above the end, IIRC.  This is just a quick test to see if the mirror can produce any sort of image.

[John]

1 hour ago, Replayy said:

Yeah I put the eyepiece in there but the image is really blurry sorry forgot to say I actually put it in.

I put it in and wheeled the sides down and up and nothing seem to get a clear image 

The tube that is pictured sat on the dust cap of the scope needs to be fitted into the focuser and then the eyepiece goes into that. Apologies if you already know that !

Astro newtonians generally can't focus on things closer than a couple of hundred metres away so your test targets need to be a good way away to enable the scope to reach focus.

 

[davidc135]

If you've racked the eyepiece through the point of best focus on a distant object and only got a blur the optics are probably not collimated i.e the eyepiece isn't aligned with the optical axis of the main mirror as directed by the diagonal. There will be adjustments that can be made on the back of the primary mirror as well as on the diagonal to help you achieve this.

To check whether the scope is approx collimated, remove the eyepiece and centre your eye on the drawtube's axis. You should see the reflected image of the spider and diagonal and your eye in the centre of view all reflected back from the diagonal. Very likely it's miles off.

David

[dweller25]

@Replayy

Where do you live ?

It could be worthwhile hooking up with an SGL member who lives close to you or going to your local astronomy club.

[Carbon Brush]

A very good suggestion from @dweller25.
I'm sure an experienced eye will identify the problems in two minutes. Given ten more minutes maybe even solve it.

 

9 hours ago, John said:

Astro newtonians generally can't focus on things closer than a couple of hundred metres away so your test targets need to be a good way away to enable the scope to reach focus.

Absolutely. When tinkering with reflector scopes I used to be surprised at just how far an object has to be to achieve focus. Now I just accept it.
Often a garden length is not enough. Unless you have a country estate🤣

[PeterStudz]

6 minutes ago, Carbon Brush said:

Absolutely. When tinkering with reflector scopes I used to be surprised at just how far an object has to be to achieve focus. Now I just accept it.
Often a garden length is not enough. Unless you have a country estate🤣

I agree. When I got my old Newtonian I could just about focus on a distant chimney pot, but I wasn’t convinced that was far enough. In the end, the only way I could be sure, was to take it out at night, prop it up with some garden furniture (there wasn’t a mount) and try to focus on some random stars. 

[TiffsAndAstro]

If I happened to stumble across an old newt with the idea of messing around with collimation *just for the lulz* is there an easy way to tell if it has a spherical mirror?

[vlaiv]

7 minutes ago, TiffsAndAstro said:

If I happened to stumble across an old newt with the idea of messing around with collimation *just for the lulz* is there an easy way to tell if it has a spherical mirror?

Two things come to mind - first is to check for off axis coma and second is to get Ronchi eyepiece:

https://www.firstlightoptics.com/specialist/gerd-neumann-ronchi-eyepiece.html