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Sky-Watcher 'SP-Series' Super Plossl Eyepieces - 20mm
by Revier
The plossl is the most widely distributed and available type of eyepiece available to the modern astronomer , it can be considered the work horse of the eyepiece world. With a myriad of focal lengths and a simple but effective design, its no wonder the humble plossl has come to dominate over such antiquated designs as the Ramsden and ... Huygenian.
Skywatchers 20mm super plossl represents a benchmark in quality within the low cost category of eyepiece. Using the more traditional 4 lens design as Skywatcher have here, enables them to keep a minimum of glass between the observer and the object being observed, until you get into the premium eyepiece category and are willing to pay the correspondingly higher prices the less glass used in an optical system the better.
To go on those lenses, Skywatcher use an excellent multi layered coating to get as much light through, in the most uninterrupted manner possible. The edges of said lenses are also blackened to improve contrast and avoid stray light, one can imagine the importance of contrast when observing the large diffused galaxies the 20mm plossl excels in displaying.
Optically the 20mm performs brilliantly (considering its incredibly low £20 price tag). Of course there are slight coma issues (especially on my f5 Dob), but I've used eyepieces at 3 times the price which have demonstrated worse abberations.
Around the lip of the eypiece is a comfortable fold up rubber cup, to keep out local light pollution, I prefer this design to the twist up plastic shield variety but that will come down to personal taste. A textured rubber safety ring encircles the waist of the eyepiece, which may sound inconsequential but becomes very important when handling the eyepiece with cold deadened fingers, anything which affords the observer extra grip has to be a good thing.
Considering how expensive astronomy can be as a hobby its wonderful to find a bit of kit that performs so well while sporting a ridiculously low price tag, every astronomer should have a handful of Skywatcher's super plossls in their inventory.
To summise, you quite literally won't find a cheaper eyepiece, let alone one that performs so well. Uniting three of the most important aspects of optical quality, practical comfort and affordability shows why Skywatcher are king of the low cost eyepiece.
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Televue x5 Powermate
by Revier
For years Televue have been top of their game, producing amongst the highest quality astronomical goods from eyepieces to telescopes and everything in-between. When the head of your company is a dedicated astronomer himself as is the case with Al Nagler, you know that quality will be put ahead of profits and that every piece that's sold ... is the best it can be.
Having said quality is put before profits, owning something made by Televue generally doesn't come cheap, but the point is that it's worth the price, several times over.
The 5 x powermate from Televue should not just be considered a good quality barlow, far from being a clever piece of branding, the powermate monicker is indication of an entirely different beast altogether.
Even the very best of barlows consists of negative lens elements (usually 2 or 3), which increases the exit pupil (the cone of light that makes it through the eyepiece into your eyeball). This can cause considerable vignetting (a darkening of the image towards the outer portions of the field of view) especially in longer focal lengthed eyepieces. The powermate, however, uses 4 elements which utilise 2 positively curved lenses, this bends the light back keeping the exit pupil where it should be, eliminating vignetting and false/inaccurate colour rendition.
Using their trademark high quality lens coatings means maximum light transmission and almost no light loss despite the addition of 2 extra lenses. In fact, apart from the increase in magnification the powermate is barely noticeable at all, just the way it should be.
As x 5 magnification is a significant increase in magnification it is true that the PM will only get used on the nights where the seeing allows and although this won't be every night, the sheer quality of the images observed will justify its rare useage.
It is worth noting that the powermate is weighty (reassuringly so), its heavier than the barlows you might be used to using, this could cause problems for the cheaper focusers that are already struggling under a weighty imaging train, just something to bare in mind.
At £150 the PM is not cheap but it is one of those rare items that fully justifies its seemingly exorbitant asking price, it provides a large increase in magnification to the visual observer and imager alike and it does it without introducing any discernible ghosts or gremlins Using a brass compression ring for eyepiece/camera attachment is a welcome feature, meaning there will be no unwanted scuffing of barrels.
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Watch House Equatorial Platform
by Revier
Owning a Dobsonian telescope has many benefits, chiefly, it allows the astronomer to get hold of the largest aperture for the lowest £££. In this hobby it has to be said that size does indeed matter. The main tube of the telescope sits on an incredibly simple and incredibly cheap mount and it's this cheap mount that is the making and ... breaking of the Dobsonian.
The simple mount of a Dob does not allow accurate tracking of the night sky which is where the equatorial platform comes in. Placing your Dob (along with its mount) on this platform will allow you to track objects as you observe them. That is to say- as long as the platform is aligned to the north- objects will remain centered in your eyepiece rather than drifting accross the field of view, the more accurately the platform is aligned, the longer an object will remain centered.
My experience of the watch house platform was initially marred when I received the package only to open it up and pour out the shattered contents onto the floor. Although highly distressing it did give me a chance to experience the excellent customer service demonstrated by watch house. They arranged for the package to be collected at their expense and promptly sent another one in its place, this time it arrived in perfect order. I must stress that the problem was caused by the delivery service and not at all by watch house. The package had been labelled 'Scientific instrument, please handle with care' and someone had clearly seen this as a challenge and gone to some considerable and persistent effort to dismantle this hated object.
On receiving the second platform I ran into a problem of my own making which again was not due to watch house at all, in my mentioning it here, I hope to save any hassle for anyone considering the purchase. I had read on watch houses website that you need a sturdy, level place to operate the platform, being an idiot and far too hasty as I usually am I dismissed this warning, thinking my back lawn would be fine. Needless to say I was wrong, you really do need a level patio to run these things on. Since receiving my platform I have levelled a paving slab with a spirit level in the garden and now it tracks brilliantly.
I still think £445 is an absurd amount to pay, especially when you see how basic it is. When I first received the platform, I was a bit surprised by how bare it looked, there are no bells and whistles and re-setting the 50min-1hr tracking run is done by hand. Watch house remain the only major platform retailers in the UK (I guess thats how they can get away with charging that amount).
Although bare, and a little bit rough and ready looking, there's no denying that the platform performs well. If enough care and attention is paid to aligning the platform accurately then any object will remain centered in the eyepiece even at high powers for the duration of the tracking run.
One of the most important applications of the platform is in astrophotography, it allows the Dobsonian owner to get involved in lunar/planetary imaging and I've even been able to get some reasonable results on some of the brighter messier objects such as m57 and m42.
To summarise, Watch house as a company are reputable and employ great customer service. The platform (provided it has an appropriate area to operate from) runs smoothly and consistently and although I believe £445 is too much for what it is, the watch house remains the lowest cost solution to Dobsonian tracking for those who are rubbish at DIY.
Anybody whose handy with a hammer would save themselves a bundle as platforms can be built for about a quarter of what Watch house is charging but as they have the monopoly in the UK they can charge pretty much what they like.
***It is important to note that every 100 hours or so the rubber grip on the roller will need replacing, but you can obtain the part easily from watch house themselves and it equates to about a tenner every 6 months or so.***
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