Skywatcher/OVL Hyperflex 7.2-21.5mm zoom eyepiece - T-Thread???

[rjc404]

Does anyone who has one of these zoom eyepieces know if there is a t-thread hidden under the twist-up rubber eye-cups like there are on some other zooms?

I don't have a zoom in my set yet and don't want to break the bank. I just aim to use it mainly for visual e.g. being lazy with one 'no faff' eyepiece or when I'm being more dedicated, scoping out the seeing at different magnifications before changing to a dedicated eyepiece.

I'd only use it for occasional photography but would rather buy one with a T-thread.

For reference here are the different branded versions I can find:

OVL Hyperflex version: https://www.firstlightoptics.com/ovl-eyepieces/hyperflex-72mm-215mm-eyepiece.html

Skywatcher Hyperflex version: https://www.365astronomy.com/SkyWatcher-HyperFlex-7E-7.2-21.5mm-High-Performance-Zoom-Eyepiece.html

 

I had read in the previous thread that the Lunt version of this zoom is also generic but the only one I can find looks quite different and is twice as expensive and has a different field of view so not sure about that?

https://www.firstlightoptics.com/lunt-solar-accessories/lunt-125-zoom-eyepiece-72mm-215mm.html

Thanks for any feedback (or any other recommendations for circa £100 zoom lens that might have a hidden T-thread)!!!

 

[David Smith]

I've got one of these and just had a poke around, can't see any evidence of a t-thread hiding anywhere. The twist-up eye-guard appears to be glued in place and the twist mechanism doesn't appear detachable.

[John]

I have one under another branding and it does not have a T-thread under the rubber eye cup I'm afraid. The eye cup is actually quite difficult to remove and when you do what you are left with is a metal ring that twists up and down (usually with the eye cup on it) but no T-thread.

I do think all the versions that you link to are the same eyepiece though. The Lunt does have a different colour segment but otherwise is the same design. I don't think the AFoV figures are always given that accurately. Same for other zooms ie: the Baader 8-24 which has been measured differently from what the specs say.

By comparing it with other eyepieces that I have, I would estimate the AFoV to be around 38 degrees at 21.5mm and 55 degrees at 7.2mm.

Here are a couple more versions of it:

http://www.opticstar.com/Run/Astronomy/Astro-Accessories-Telescopes-Opticstar.asp?p=0_10_5_1_8_330

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p4651_TS-Optics-Premium-Zoomokular-7-2-mm-bis-21-5-mm---1-25-.html

I'm very pleased with mine despite all the above confusion and use it often with a Baader 2.25x barlow to get a high power 9.55mm - 3.2mm zoom

I have to admit though that my version cost well under the prices currently being asked even by FLO.

 

 

[johninderby]

Have the TS version and find it to be a very good zoom. Like it. 👍🏻

And no there is no T-thread under the eyecup , just the twist up arrangement. 

[rjc404]

Thanks to all for replying so far.

Oh well, no T-thread... but I haven't really found someone who dislikes these zooms so some thinking to do...

The only other one in a similar price range with these is the Celestron 8-24, which does have a T-Thread hidden under the eye-cup - will have to check out some reviews of that to see how it performs.
f it doesn't appear as good I might go for one of the generic Hyperflexes above anyway. I am half tempted with the Baader 2.25 barlow as that's still quite cheap in a few places.

https://www.rothervalleyoptics.co.uk/celestron-8-24mm-zoom-eyepiece-125.html

and this Q&A which confirms the 93230 does have t-thread https://www.celestron.com/blogs/knowledgebase/does-the-93232-deluxe-zoom-eyepiece-have-t-threads (but not filter threads on the barrel :/)