orion skyquest 8" v. "skywatcher skyliner 8

Captain Furball

Which of these dobs is the best buy? I've seen that they are both made
by the same Chinese company and have the same optics. So is there any
difference apart from the orion costing a lot more?

SKYLINER 8" €350

http://www.opticalvision.co.uk/astronomical_telescopes/sky-watcher/dobsonians/skyliner-200p

orion skyquest 8" €590

http://www.orionoptics.co.uk/DOBSONIAN/dobsonian200s.html

dbran

Hi

So you are thinking of getting a scope

Well first off just to say I dont own a dobsonian, but an SCT so maybe someone else will be able to add or subtract stuff to my answer.

First of all, do not be so fooled by rosy reviews from magazine. Magazines are dependect to a certain extent on keeping their advertisers happy and will be wont to put them out of favour to other similar astronomy magazines for advertising revenue.

1) The skyliner has a wooden mount whereas the orion has a metal one. This would possibly lead to the orion being more sturdy and less likely to wobble in the wind etc.

But......

2) I note that the skyliner has a parabolic mirror and is denoted as a 200p. Therefore does this mean the orion 200s have a spherical mirror? This is critical and dont part with your hard earned dosh without the answer.

Check this out http://users.zoominternet.net/~matto/M.C.A.S/mirrors.htm !!!

If the "s" means it is a spherical mirror then for an aperture of 8" not all the light will be focused correctly at one point and strangely enough it seems you will not get as sharp views as in the cheaper scope. hmmmmmmm

I note that nowhere does it say in the blurb if it is spherical or parabolic. Just that it gives great views!!!!!!!!!

So I would tend to actually say get the cheaper scope. If you can live with a bit more shake and roll you will be able to get better views when it settles down. You may even be able to change the rocker box later for a better mount at a later date. It all depends on what that "s" means and the type of mirror.

Good luck:)


DB

Stargate

Captain Furball wrote: »

Which of these dobs is the best buy? I've seen that they are both made
by the same Chinese company and have the same optics. So is there any
difference apart from the orion costing a lot more?

SKYLINER 8" €350

http://www.opticalvision.co.uk/astronomical_telescopes/sky-watcher/dobsonians/skyliner-200p

orion skyquest 8" €590

http://www.orionoptics.co.uk/DOBSONIAN/dobsonian200s.html

Hiya Captain Furball

At the start of the year i spent months looking for a scope online ,
this scope is similar , are the prices you quoted Sterling Or Euros ?
Have a look here at a 10 inch dob ,cheaper than the 8 inch you meantion.
Bigger Apeture , More Light

http://www.warehouseexpress.com/buy-sky-watcher-skyliner-250px-10-inch-dobsonian-telescope/p10567

Regards
Stargate

slade_x

dbran wrote: »

Hi

So you are thinking of getting a scope

Well first off just to say I dont own a dobsonian, but an SCT so maybe someone else will be able to add or subtract stuff to my answer.

First of all, do not be so fooled by rosy reviews from magazine. Magazines are dependect to a certain extent on keeping their advertisers happy and will be wont to put them out of favour to other similar astronomy magazines for advertising revenue.

1) The skyliner has a wooden mount whereas the orion has a metal one. This would possibly lead to the orion being more sturdy and less likely to wobble in the wind etc.

But......

2) I note that the skyliner has a parabolic mirror and is denoted as a 200p. Therefore does this mean the orion 200s have a spherical mirror? This is critical and dont part with your hard earned dosh without the answer.

Check this out http://users.zoominternet.net/~matto/M.C.A.S/mirrors.htm !!!

If the "s" means it is a spherical mirror then for an aperture of 8" not all the light will be focused correctly at one point and strangely enough it seems you will not get as sharp views as in the cheaper scope. hmmmmmmm

I note that nowhere does it say in the blurb if it is spherical or parabolic. Just that it gives great views!!!!!!!!!

So I would tend to actually say get the cheaper scope. If you can live with a bit more shake and roll you will be able to get better views when it settles down. You may even be able to change the rocker box later for a better mount at a later date. It all depends on what that "s" means and the type of mirror.

Good luck:)


DB

The link you just posted states "A parabolic's deeper, more complex figure focuses all incoming light rays to the same point, so images appear crisp and sharp, without any distorting effects of spherical aberration"

Although that is true in saying no spherical abberation is present it says nothing about other abberations inherent in parabolic mirrors such as coma , astigmatism and curvature of field

for some cheap even some odd midrange scopes using parabolic mirrors its quite possible to get a worse result than with a spherical concave mirror

Spherical concave mirrors are subject to only spherical abberation and this can be remedied by using combinations of concave, convex and aspheric lenses such is the case with Schmidt and Maksutoff optics which are used in catadioptric and compound telescopes respectively


Here's a good little guide on exactly what the abberations are
http://en.wikipedia.org/wiki/Optical_aberration

To the original poster, if you are willing to invest up to €600 you could get into the 10" range (even an 8" meade lightbridge would be much cheaper than the orion, for a little extra you could have the 10" one), i doubt you will find much of a difference between both of those scopes, however just because 2 ranges of telescopes can be assembled by the same factory doesnt mean all the parts are of the same source and standard. orion optics do provide better optics in their scopes, but whether or not you personally could perceive the difference, is still debatable. science vs sense

Calibos

OP,

You've linked to an Orion Optics UK dob not an Orion USA Skyquest Dob. Totally different companies. Orion UK mechanicals will be better and you'll get a gauranteed 1/4 wave primary mirror whereas with the SKywatcher or Orion USA Dob you have no guarantee you'll get a true 1/4 wave primary. Keep in mind though that it would take an experienced eye to tell the differance and chances are you will get a good mirror with the other two, its just they don't guarantee it. The odd lemon slips through.

The Orion USA 8" dob equivelent of the Skywatcher is the same UK price of GBP299.

http://www.scsastro.co.uk/it030024.htm

Or you could pay a bit more than the Orion UK €580 and get an Orion USA 8 .....Intelliscope...... Dob for about €650

http://www.telescope-service.com/OrionUSA/dobs/dobs.html#In8

These have a scope computer to tell you where to point the scope. You still have to move the scope by hand but the scope computer by means of arrows and numbers on the display enable you to point the scope exactly at an object in seconds. It has a 14000 object database.

Captain Furball

Wow I wasn't expecting this much interest in my post.
I'm taking my time choosing a scope as it's my first and probably last for a good while.I know it's very easy to get to a certain scope when they say things like "it gives great views!".The explantion of the different mirrors was interesting.

Stargate what type of scope have you?And what are you able to see with it? I want to see as much as i can.Will i see things with the 10" that I would only see as a dot with the 8"?

As for the different types of glass that's used in the primary mirrors -what do i look for?I'm curious how does a bigger mirror enable you to see things further way?I know on the guides i've read it explains it lets in more light but how does that work exactly? The only thing i understand about light is it travels at 333,000,000 meters a second or something in a straight line?

Calibos I thought they were the same company my mistake. What do you mean by a "1/4 wave primary mirror" and how is that good compared to the others.I want to spend the least possible and learn as mucyh as i can so i don't think i'll get one of the computer driven motors for the scope.

Thanks for all the replies! I wasn't expecting anything like the replies you've wrote.
Cheers.