E-bay scopes - BEWARE!!

[Carlos_dfc]

We've all seen those generic newtonians they sell on e-bay....

Names like 'Event Horizon', 'Seben'. 'Optrons', 'B&Crown', Scopetronix'
Well I had the (mis?) fortune to get the chance to try one out a while ago - Here's the mini-review I wrote a while ago, when someone asked about them, and the experience was fairly fresh in my mind:-
(this is a straight 'copy'& paste' from where i originally wrote it)

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These scopes are sold under 5 names that I know of, ('Scopetronix', 'Optrons', 'B&Crown', 'Event Horizon', and 'Seben') possibly more - the scopes are identical, but they sell them in 4 different colours, under 5 different brand-names for some reason.

I got to try a 6" (150mm) f1400 'Event Horizon' model, side-by-side with my own 6" 'Skywatcher Explorer' at the 'Kielder star camp' event.
The guy next to me was a total newb, and had bought one through e-bay, I got talking to him, showed him how to polar-align, and then found a few things for him, so I got to have a look at a couple of 'showpiece' targets through it.
I also used my own 25mm. 10mm, and 6mm eyepieces in it, (with 2x barlow to 'equalise' magnification in my own faster scope) so I could get fairly close to a direct comparison.

The e-bay scope had a spherical mirror, with a 'corrector' lens in the bottom of the focuser drawtube, which IMHO didn't work very well at all.
Focusing at high magnifications was near impossible (very VERY narrow depth of field)
At low magnification, it was possible to focus the centre of the field of view, but the edges were well out-of-focus when the centre was sharp-ish, which suggests very bad field curvature (I say 'sharp-ish' because no matter how I tried, I couldn't get it as sharp as I was used to seeing with my Skywatcher)
Bad field curvature, as well as very narrow depth of field - no wonder it was so difficult (near-impossible) to get a sharp image.

I checked collimation with my own laser collimator, and it seemed to be pretty close to spot-on (well - as close as I could hope for, bearing in mind how loose and 'sloppy' the focuser was)
Contrast was also very poor compared to my Skywatcher, and I reckon the SkyWatcher was getting an extra magnitude, maybe more, than the e-bay scope was getting (Strange, because they were both 6" aperture, so theoretically they should have been pretty close to each other on that point) maybe this was caused by the poor contrast, or maybe the coatings on the e-bay mirrors weren't as reflective as the Skywatcher - I couldn't really tell.

The Mount - very wobbly - it had no locator pin on the tripod to lock left-right polar alignment onto - had to rely on getting the mount-to-tripod bolt tight enough to hold it (Skywatcher has a locating pin, with a screw from each direction to lock onto the pin). The up/down (lattitude) setting only had one adjusting screw, with a clutch (a bit like an RA & dec clutch) to hold it in place. (Skywatcher has two bolts, one from either direction, to 'lock' the lattitude in place)
The RA and Dec clutches didn't hold particularly tight either, and all these things added up to mean that I had to be careful not to lean too heavily on it, or some of the settings would 'shift' very easily. Slo-mo controls had a 'notchy' feel to them, and the mount head itself was nowhere near as chunky as a 'Skywatcher EQ3-2. In fact the whole mount had the look and feel of an EQ2 (BUT - a very badly put-together EQ2 at that) - and a scope this size really does need a decent EQ3 or better.

A few viewing comparisons:-
Bear in mind that Kielder is a VERY dark site, conditions were superb.

Perseus double cluster - through the Skywatcher, was beautiful, like myriad tiny diamonds, concentrated in two clumps, scattered on black velvet - through the e-bay job, a bit lack-lustre, like salt grains on a dark grey piece of card. I could get the centre of the field sharp, but because the outer 50% of the field was fuzzy, the outer edges of the two clusters were in the 'fuzzy' area. I could centre on one of the clusters at a time, but the other one would be in the 'fuzzy' zone. Couldn't get them both sharp, while together in the same field of view.

M57 - Ring nebula
Skywatcher - nice sharp ring, right up to 250x, clearly defined, and distinct, best I've ever seen it due to the superbly dark sky.
e-bay job - OK at low magnification, small but well defined - At 140x it was bigger, but starting to 'merge' into the background, and at 233x was only just visible.

M81 and M82 - Bode's galaxy and the cigar
In my Skywatcher they really jumped out at me compared to what I'm used to seeing at home, the dark sky of Kielder made a huge difference - from home all I can see of M81 is the bright core, here I could see a bit of structure - I could even see darker dust patches in the cigar, from home it is no more than an elongated smudge.
Through the e-bay newt, M81 was just a smudge (the core), and I struggled to see much of M82 at all, just a thin 'smear'.

I showed the guy who owned the e-bay scope, a few things through the Skywatcher - the first thing he looked at was the double cluster, when he put his eye to the scope he gave out an audible gasp, followed by 'WoW!s' - the difference was THAT striking.

Overall, the e-bay 'specials' are very poor. I've seen them go on e-bay for around £80 (sometimes less). About the same price as a pair of Celestron 15x70 binoculars.
Given the choice of a freebie, I'd pick the Celestron binos before the e-bay scope, every time.
If you want a scope, and definitely can't afford any more, then it's better than NO scope - just!!! and it is a long, Long, LONG way behind the likes of Skywatcher, Orion, Celestron, Meade etc.

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Steer clear - you have been warned...

Carlos

[mugect]

Carlos - just checked out your comments, thanks. I as well have wondered about this scope, and your review has confirmed what I thought - you pretty much get what you pay for.

[FatherGuse]

... or worse yet ... I picked off a decent used Meade not to long ago for a serious bargain-basement price (about $40.00 including shipping), and I guess the seller got ticked off at the closing price so he shipped it without any padding in a home-built carboard box ... it was smashed to bits by the time it found my door (with generous amounts of postal tape to keep everything together) ... I made out okay on the "parts value" of the sale, but it sure would have been nice to clean up a perfectly good scope and donate it to the local Natural Science Museum for their kids astronomy programs ...

... well ... now I have a spare motorized go-to DS series yoke mount ... and some hardware ...