Skywatcher Hyperflex 9-27mm zoom

[JonnyK]

Has anyone got any experience with these zoom eyepieces?Are they any good or a bit of a gimic?I'd be using it on an 8SE

[Eastman]

Maybe 5 years later? 

I do have the same question.

thanks in advanced

[Geoff Barnes]

Perhaps 5 years of silence speaks for itself?

I can't recommend the Baader 8-24mm zoom highly enough, it is wonderful. ?

Edited January 25, 2019 by Geoff Barnes

[Louis D]

Well, this SW HF 7E2 zoom looks to be identical to the ubiquitous 7.2-21.5mm zooms such as the Skywatcher Hyperflex 7E1, Lunt, Orion Zooom!, Opticstar XL, Omegon Cronus/Premium, Orbinar HQ FMC, Solomark Planetary, and TS HR Planetary differing only in focal length bounds.  I would imagine the two utilize very similar lens designs and so probably perform similarly, differing only in magnification.

[Eastman]

After more than a 1000 views and no enthusiastic user reviews I guess I have a answer too!?

[John]

The 7.2-21.5 zoom is pretty good quality and may well be from the same source as the 9mm-27mm that is the subject of this thread.

A similar post on the Coudynights forum got no feedback either, which suggests that these might not be a good seller !

https://www.cloudynights.com/topic/540173-9-27mm-zoom-eyepiece/

 

[Ags]

Well, it is 2022 now, and I have the same question... Has anybody used a Hyperflex 9-27 zoom? 

I know the 7.2-21.5 is quite good but not sure the 9-27 is in the same league. Thinking it would be a good match for a Solar Scout SS60-ds (f-ratio = 15.5). 7.2mm would be too much magnification for me, and 21.5 @ 40 degrees isn't wide enough for untracked viewing. With a barlow the 9-27 would give 4.5 -13.5 which is very useful. Or about 6-18 with a screw-on barlow nosepiece.

Edited April 4, 2022 by Ags

[Louis D]

Recently, I measured the actual focal length of my Surplus Shed 7.2-21.5mm zoom and came up with 7.4-20.6mm, so a bit short on both ends.  It's not as bad as my Celestron Regal 8-24mm zoom, though.  It measures out to be 8.2-21.2mm!  All I'm saying is, don't bet the farm on the 9-27mm zoom being 27mm at the long end.  It probably will be pretty close to 9mm on the short end, though.

Also, remember that many 2x Barlows are closer to 2.1x to 2.4x in your calculations, depending on where the eyepiece focuses relative to the Barlow's shoulder and the native power of the Barlow if the eyepiece reference plane is exactly at the shoulder.

What about using a hyperwide 9mm eyepiece like the APM XWA for general viewing?  You'd get plenty of dwell time at a reasonable power.  I see you have some 82° eyepieces in that range already.  Is this more about putting together a travel kit or trying to chase the optimum power in real time?

[Ags]

I can see a few uses for it, assuming the wide end is as wide as advertised. Firstly as a cheap travel eyepiece with my f6 Zenithstar 66. Secondly as a solar eyepiece to chase the right magnification (either in white light in the Zenithstar, or in hopefully a Solar Scout in Ha). Bear in mind my eyes don't let me go far below an exit pupil of 1mm. Thirdly as a planetary eyepiece with my C6, moving between mangifications in the range of 9-15 mm.

With a barlow, it would be a double star eyepiece in the Zenithstar, or in the larger ED RFT I plan to get.

I think the twist up eyecup should be good at solar as it would shield the eye lens effectively.

I have most focal lengths covered; ultimately this is about adding a different experience.

Edited April 4, 2022 by Ags

[Greymouser]

I have it and so far like it. Of course, I have not had enough use to come to a proper conclusion, but so far, so good.

As circumstance allows, ( Which is not all too often... ) I will use more and try to remember to report on it.

[Louis D]

How about the Svbony SV170 10-30mm zoom eyepiece?  It's only $50+tax over here direct from Svbony's store, and £59.99 on Amazon UK and £55.99 on ebay UK.  I couldn't locate a Svbony storefront in the UK.  At least one person on CN likes theirs.  Svbony also sells the 9-27mm zoom for about $90 to $100 +tax over here.

[Ags]

SV170 has 33° FOV at the wide end - not for me 😀

Edited April 5, 2022 by Ags

[Louis D]

True, but the true field of view would only be 8% narrower in the 10-30mm if all the focal length and AFOV values are accurate.  By the time you get to a 40° AFOV, it's feeling mighty narrow.  33° will be worse, but you're already deep into the uncomfortably narrow zone anyway.

[cajen2]

This is presumably the same zoom as the OVL Hyperflex? I have this, though I don't use it much, but I do find the images are good with it. It's the 21.5 - 7.2mm version.

[Ags]

58 minutes ago, Louis D said:

but you're already deep into the uncomfortably narrow zone anyway

45 degrees is quite ok with my SLV 6mm, so 40 should be allright. But 33 - I don't even want to try! Also it will have narrower true field than the 9-27 with an exit pupil that is getting slightly too large for me, so the 10-30 range doesn't have advantages for me. 

[Greymouser]

21 hours ago, Louis D said:

How about the Svbony SV170 10-30mm zoom eyepiece? 

I have the Svbony 8 - 24 eyepiece, which is good and improves with the use of a  barlow. ( Baader 2.25x ) I would also say the Hyperflex is better, though I am unsure yet, as to how it will be with a Barlow.

[globular]

On 04/04/2022 at 23:04, Greymouser said:

I have it and so far like it. Of course, I have not had enough use to come to a proper conclusion, but so far, so good.

As circumstance allows, ( Which is not all too often... ) I will use more and try to remember to report on it.

Hi @Greymouser

How have you found the 9-27mm zoom over the last few months?

Is the FOV really 40 to 60?  I have the similar looking Hyperflex 7-12 zoom (also claiming 40-60) but it measures more like 38 to 55 to me.

And how is eye relief?  The claimed 18mm (rather than the claimed 15mm of the 7-21) is the main thing that's caught my eye.  Is that about right do you think - i.e. a bit more than other similar zooms?

[Greymouser]

@globular I have hardly used it the last few months, because I have hardly had any sessions, under the stars. To many other commitments; a very tired failing body and clouds. However, my view is still the same, it is a very good eyepiece and the figures sound about right, though I far from an expert. I have used very few zooms. Hope that helps. 

[globular]

3 minutes ago, Greymouser said:

@globular I have hardly used it the last few months, because I have hardly had any sessions, under the stars. To many other commitments; a very tired failing body and clouds. However, my view is still the same, it is a very good eyepiece and the figures sound about right, though I far from an expert. I have used very few zooms. Hope that helps. 

Many thanks