200mm scopes

[beanyboy1982]

morning all come across this on ebay what do you all make of it, is it going to be another rubbish scope and could get better for the money ?

http://www.ebay.co.uk/itm/8-TELESCOPE-203mm-REFLECTOR-BRAND-NEW-/190776175105?_trksid=p2047675.m2109&_trkparms=aid%3D555001%26algo%3DPW.CURRENT%26ao%3D1%26asc%3D29%26meid%3D4841700459144587426%26pid%3D100010%26prg%3D1013%26rk%3D3%26sd%3D160954770800%26

[Cornelius Varley]

You were right with your first thought. The telescope is sold with an eyepiece sun filter and the seller tells you not to use the telescope to look at the sun.

[skygazer]

More than likely, ask the seller if it's got a parabolic mirror (shaped like a bowl) or a flat mirror. If it's not parabolic then it's over priced and won't be that God.

I would recommend this

http://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-150p-dobsonian.html

I have the 200mm version and it's an excellent scope for the money.

Paul

Sent from my Nexus 4

[brantuk]

The counter weights might be good - and it has a nice box - apart from that your money is best spent elsewhere imho

[Cornelius Varley]

The mirror is most likely to be spherical rather than parabolic (a flat mirror wouldn't work as a telescope mirror). At f4 it would be difficult to collimate and the spherical mirror would give nastly spherical abberations.

[Capricorn]

Notice that the main advert say 8" (203mm), the item specifics bit say 150mm.

The mount at the top of the advert (black) is different tothe later one (white), the white one looking more substantial.

If 203 dia and 750 FL then F/3.75 then is going to need eyepieces costing more then the scope to be any use.

The box image when expanded almost looks as if it says 203mm/1200mm - difficult to be sure.

If the seller has measured the OTA length and come up with ~750mm then this would mean something like the Bird-Jones design where the extra focal length is taken care of by something resembling a barlow at the focuser. Principle is good but the components used in mass production usually means really bad quality. Throw in that many use spherical mirrors and whats starts bad gets worse.

[rwilkey]

Too risky, anyone who sells a scope with a sun filter must be avoided, stick to proven makes of telescopes like Sky Watcher for example. The one in the advert looks shoddy and also there is the question of whether it is a 150mm or 200mm, the seller does not give the focal ratio, but based on the length and the aperture stated it looks very fast at f/3.75, almost impossible to use visually or get suitable eyepieces for. Steer away in my opinion.

[beanyboy1982]

sent them the question on what type of mirror it has and got this back It uses a semi-parabolic mirror to give a shorter tube for a given focal length.

[beanyboy1982]

also looked through their feedback and seen that someone had bought one off them so i asked them what it was like and got this back off them

Hi, the scope assembled fine although needed a couple of the adjusters tightening but if you are technically minded at all this is not a problem. As for the optics I have not been able to see anything yet due to the weather. That said I have set it up and aligned it during the day and buildings etc appeared sharp and focused from a good few hundred metres.

[Aronnax]

Like the previous responses, I would give this a miss. There are too many question marks over what it actually is you get for your money, and far too many unknowns about the brand.

If the initial specs are correct, this is a *very* fast scope which will not cope without some *very* good eyepieces.

Unless you can get some hands on with it beforehand, or know a trusted someone with experience of the scope and mount, I would err on the side of caution and give this a miss.

[beanyboy1982]

yeah going to give it a miss just wanted you to know what reply i had had thanks all will keep saving for a 150 or a 200 dob skywatcher

[skygazer]

Wise decision, I nearly bought a cheaper score before I got my 200p, really glad I didn't

Paul

Sent from my Nexus 4