“ Brand: Televue / Type: Eyepiece „
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.