Seben 31.7mm 1.25“ Zoom 8-24mm

[Greymouser]

I have never had a Zoom eyepiece, so thought I would give this one a whirl, so to speak.  ( a cheap introduction, I thought. )      https://www.amazon.co.uk/Seben-31-7mm-8-24mm-Telescope-Eyepiece/dp/B00663XV8S

I did look several places, but only found any in stock on Amazon, ( there were 11 in stock then, 1 now, so going fast, ) which made me nervous, considering my experience with their packaging... However for £ 60.99, I thought it was worth a punt, especially as some people have said it is basically the same eyepiece as the Skywatcher/ Celestron zoom; certainly it looks very similar. I was right to be worried about Amazon packaging, there was no padding or bubble wrap at all, but I got lucky as the eyepiece is in one piece and appears to be working fine! It comes in its own little cylinder, not unlike an old 35mm film case, though obviously larger. 

Tonight I finally got some clear skies to give it a little try, only in my ST102, but still. I went to M42, of course and was impressed with the view, Sharp across most of the view, which surprised me. It is very easy to zoom in with this eyepiece and the view just got better and better, with the 24mm setting being the worst. This gave me a magnification range of about 20.8 - 62.5. I was impressed that the trapezium became obvious about halfway. I then though I would try the zoom with Baader Q-Barlow, 2.25, which gave me a range of between 46,8 - 140.6, which was decent. This Barlow is much better than the standard one offered by by Skywatcher! Again I was impressed, in fact I would say it seemed to be sharper, if anything! I was also impressed that there was little adjustment needed on the focuser, across the range.  

It was hard to see much detail in the nebulae otherwise, because of an almost full moon. I decided to go and have a look at that next. After nearly blinding myself, ( why did I leave the moon filter in the house, again? ) I had a go with just the zoom and lower mags. I was disappointed to see more CA than I was expecting; but was this the zoom or just the poor ST optics? I had not used the ST for a while, so will check when I get my C9.25 out next time, whenever that will be. However the view was again still sharp, only distracted a bit by the greenish CA around the rim, manageable I thought.

Next I added the Q zoom, expecting it to make things worse if anything, but what John posted in his happy coincidence thread is true with this eyepiece, too! The CA all but vanished, what's that all about then? ( Thank you John for that hint! ) It was sharp pretty much all across the view and I could have spent hours looking, but clouds intervened.

In conclusion I would say this is a very good eyepiece and I am well impressed, particularly in combination with the Q Barlow. I am now a convert to the zoom and may consider a more expensive one in the future. ( Far distant! ) Certainly I think this would be a great mini eyepiece collection for my upcoming travel C5, all the eyepiece I will need in combination with the Q Barlow and maybe the reducer. I would highly recommend both, especially at £ 61 for the zoom and £ 39 for Q Barlow!

Hope this mini review helps anyone looking and wondering about such a cheap zoom.