Jump to content

Banner.jpg.b83b14cd4142fe10848741bb2a14c66b.jpg

Reflector vs refractor


Recommended Posts

  • Replies 25
  • Created
  • Last Reply

I think your 127 power seeker has a focal length of 1000mm and is what is known as a "bird jones" design, with a corrector lens at the bottom of the focuser tube. I'm I correct in that assumption ?

 

Link to comment
Share on other sites

Indeed, you have a Bird Jones telescope. These have a spherical mirror and a corrector lens in the focus tube. Not recommended,but the good news is that you are seeking for improvement and just about any design is better for the amateur.

I have a 4"  refractor and a 6" Schmidt Cassegrain telescope. The refractor is an f/5 and with its short focus it gives impressive wide field views. The SCT is about as good on the Moon and planets and better on small DSOs, but stars are less point-like in it. That makes the views through the refractor more beautiful. 

Good refractors to cost much more, but can exceed the quality of a good reflector of the same aperture by a great deal. 

The Bird Jones is a catadioptric design (mirrors and lenses). Some catadioptric designs work very well: the SCT and Maksutov Cassegrain are well respected for their image quality. The Bird Jones is not. It is more of a catastrophic design.

The best telescope for a starter would be a 6 inch f/8 Dobsonian with a parabolic mirror, a slow Newtonian reflector with little aberrations, not too demanding on the eyepieces,  relatively easy to maintain and quite versatile.

 

Link to comment
Share on other sites

7 minutes ago, Ruud said:

Indeed, you have a Bird Jones telescope. These have a spherical mirror and a corrector lens in the focus tube. Not recommended,but the good news is that you are seeking for improvement and just about any design is better for the amateur....

 

 

That was the point that I was leading up to making :thumbright:

Link to comment
Share on other sites

I  rid my Powerseeker in favour of the Skyliner, and no regrets ( well one maybe? you can get bigger scopes!!!!).
You will find the 8" Skyliner EASIER to use, you'll see MORE due to the aperture( when conditions allow ) and the scope works very well with BST Starguiders. 

Scope and eyepieces are available from the sites sponsor, and the Skyliner is still being quoted as  the UK's most popular scope. 

Pawn the  Powerseeker to a high street pawn shop, you might get just enough for your first BST eyepiece?

Link to comment
Share on other sites

Thanks for that, I think I'm going to go for a refractor as. iv'e been stargazing for about a year and a half and in that time the most most breath taking things I've seen have been the Orion Nebula and Jupiter. I have tried to see dso's but without much luck. Plus I like the idea of it being enclosed and not having to worry about mirrors moving out of line, this is what put me off getting a 10 inch dob, which was my first choice.

Link to comment
Share on other sites

When I viewed Jupiter is was pretty miserable ( Often thats down to the seeing conditions, but remember your using a Powerseeker!)

The best view ever to date of Jupiter was with my Skyliner, but that itself was a few Years back,  and my conditions, mainly weather related have been  pretty bad for over a Year now? 

Only you can decide whats best. my next scope, should I decide to expand my horizon would be an 80mm ED APO for astrophotography, or for visual alone, I'd like another skyliner,  the 12" solid tube.

Until then, I just need some clear nights and a street light power cut. 

Link to comment
Share on other sites

8 minutes ago, Hairy Gazer said:

Thanks for that, I think I'm going to go for a refractor as. iv'e been stargazing for about a year and a half and in that time the most most breath taking things I've seen have been the Orion Nebula and Jupiter. I have tried to see dso's but without much luck. Plus I like the idea of it being enclosed and not having to worry about mirrors moving out of line, this is what put me off getting a 10 inch dob, which was my first choice.

If you want to do better on DSO's you need more aperture rather than less ?

Unless you have the budget / muscles / mount for something like a 6 inch refractor.

Link to comment
Share on other sites

8 minutes ago, Hairy Gazer said:

I think I will get both eventually , but I am currently looking at either the Evostar 150 or the Startravel 150.

 

The Startravel is a good low / medium power scope for DSO's, clusters etc. Too much false colour for higher power viewing really. The F/8 Evostar 150 still shows a fair amount of false colour but is a better all round scope. Don't buy a new one though - they are much better value buys on the used market in my view.

You can see DSO's with just your eyes - it's just a matter of knowing where to look !

I can see dozens of them with my 4 inch scopes.

A 6" F/8 refractor is a large instrument and needs a heavy duty mount:

 

 

P1080676.JPG

Link to comment
Share on other sites

8 minutes ago, Hairy Gazer said:

I think I will get both eventually , but I am currently looking at either the Evostar 150 or the Startravel 150.

 

 

4 minutes ago, Hairy Gazer said:

What? Can you see DSO's with a 6inch Refractor? If that's the case I'll definitely go with the refractor, I didn't think DSO's would be an option these

DSO's are very nice in a 6" refractor. You may consider the Star Wave 152, though it is a tad more expensive than the evostar. Another seriously good alternative would be a second hand ED 120

Link to comment
Share on other sites

4 minutes ago, Hairy Gazer said:

I wouldn't mind getting a used one, but even though refractors are the most robust scopes, I'd be a bit worried that it may have been banged about or damaged in the past, most worse quality viewing than a new one.

If you got a refrac...........it would arrive safer than a reflect. Im in Ireland any my latest scope (102 bresser)   came from Germany.

Link to comment
Share on other sites

Yeah, but it's still smaller then the 10 inch dob and 10 inch reflector on an eq6 mount that I was considering a while ago. The only thing that springs to mind looking at the picture that John posted, is do I need to lie on my back to look directly overhead?

 

Link to comment
Share on other sites

59 minutes ago, Hairy Gazer said:

Yeah, but it's still smaller then the 10 inch dob and 10 inch reflector on an eq6 mount that I was considering a while ago. The only thing that springs to mind looking at the picture that John posted, is do I need to lie on my back to look directly overhead?

 

You can view from a seated position (many do) or get the scope on a nice tall tripod. Here is another 6" F/8 that I used to own - the eyepiece is around 1.5 meters off the ground in this pic:

 

helios6eq5.jpg

Link to comment
Share on other sites

Hi,

I have the ST150 and for low/medium power it is a great telescope, so if you use it for the role it is intended I don’t think you would be disappointed.  An 8” dob would be more cost effective and allow me to see deeper into the sky, but these choices are not always totally rational as there is something I love about a large aperture refractor. :)

I can only agree with what others have said around the mount.  I acquired the ST150 when I traded it with a friend for my old ST102, and the size difference is significant.  

EA1161D7-CC52-4942-AFCD-09319C834D76.thumb.jpeg.4b48c1c515ed7295ff2a72957efbe211.jpeg

I tried it initially on my AZ4; I have seen comments on here from people who are fine with that but I found it a too shaky and upgraded to the Skytee 2.  I have no experience of the F8 version, but the F5 is no lightweight so you would want to take into account the cost of a suitable mount if you go for it.

But otherwise I love it.  Sweeping about the sky hunting down DSOs is very pleasant.

The above are just my opinions, others might disagree.  Hope that helps.

Dave

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.