Telescope Reviews: First New Eyepiece for a StarBlast 6

Hi Clark,

I did get out last night with the Starblast 6 and my Hyp Zoom, as well as the 24, 17, and 8mm Hyperions. It was among the best nights for transparency we get here in the LA 'burbs— which means that it was reasonable as opposed to a horrible waste of time.

Short story: the zoom works as well in my f/5 Starblast as in my f/6 achromat and f/10 SCT.

So what does that mean? My observations in the f/5 Starblast agree with the now mostly common knowledge of the limitations of this EP (and my observations in my other scopes):

• At 24mm it has vignetted edges, significant field curvature (FC) and some astigmatism (AS), as well as a small AFOV. Since the TFOV pretty much matches the 20mm, I don't use this setting.
• At 20mm it cleans up noticeably with no vignetting, with less but still noticeable FC and less AS. Here, the AFOV is much wider and matches a 20mm Meade 4000 Plossl (4-element) at ~50°.
• At 16mm, there is even less but still some FC, almost no AS and a somewhat wider AFOV
• At 12mm, there's just a touch of FC— easily accommodated by my eye, no noticeable AS, and again a somewhat wider AFOV
• At 8mm, there's pretty much no FC, no AS, and the AFOV gets *much* wider and in direct AFOV comparison, is maybe a degree or 2 smaller than the fixed focal length Hyp 8.

The eye relief at all settings is comfortable for me with thin glasses on and I can see the entire FOV. It has a nice twist up eyeguard for regular use.

As fat as what I could see thru the EP vs the others, I viewed M4, 7, 13, 22, 27, 57 and Jupiter. The views of all except for M22 were quite similar between the Hyp Zoom set to 8mm or 17mm and the Hyp 8mm and 17mm fixed focal length EPs. In fact it was *very* enjoyable to zoom in and out on Jupiter (with and w/o a 2x Parks GS barlow), M27 and M57. 8mm is just about the perfect stopping point for those 2 nebulas in this scope. M13 and M4 left me wanting more zoom in though I didn't use the barlow with them (I have no good excuse for that). M4 is a big challenge in the backyard and in fact I've never seen it in the achro or the SCT but now on 2 successive nights out with the Starblast, I've seen it though in my even more badly LP south, it's on the edge of seeing. I spotted it at 20mm in the Zoom and dove in to 8mm to have a closer, if lackluster due to LP, look.

And now M22.

Now I am not an experienced comparer of EPs and generally don't pit them against each other though I have 3 complete lines consisting of Meade S4000 Plossls, cheap widefields (65-70°), and good but still inexpensive widefields (60-70°). Maybe I'll do that 3 way comparo one day but probably not...

Here was the first time I've compared different EPs and seen a repeatable and discernible difference. When centered in the FOV, I could see more definition and stars in the fixed focal length 8 and 17mm Hyps than the Hyp Zoom set to 8mm or 17mm. I switched back and forth a number of times and could see the individual stars in the cluster more easily, comfortably and consistently in the fixed focal length EPs. It wasn't a *huge* difference but it was a noticeable one.

In any case, I feel that the Hyperion Zoom is a very good fit for this scope as I did not see that the f/5 focal ratio diminished the Zoom's performance much if at all compared to my other higher focal ratio scopes. If I could change 1 thing about the Hyp Zoom, I'd ask for it to go from 20mm to 6mm instead of 24mm to 8mm.

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8" LX90, StarBlast 6", 100mm f/6 achro, 60mm f/5.8 achro, 10x50s, 15x70s