Hyperion Fine Tuning Rings

[Damo636]

Hi everyone. I am considering buying the fine tuning rings for use with my Hyperion EP's, the 13mm in particular. The rings give a possible 4 different focal lengths down as far as 8mm. My question is, does the addition of the rings degrade the image in any way and would an 8mm without the rings outperform the 13mm with the rings attached? I normally use my TMB Planetarys when at that focal length but really loving the widefield view of the Hyperion.

Cheers

Damo

[John]

I tried the 14mm and 28mm Hyperion Fine Tuning rings a couple of times when I was testing a set of Hyperions a few months ago. They don't appear to degrade the quaility of the view or reduce the field of view so they "do what it says on the tin". The extended eyepieces can get quite bulky so you need a good solid focuser / diagonal. This is the 5mm with the 24mm ring in place with a Vixen LVW 5mm for comparison:

[Macavity]

I felt that to some extent the image (or rather ease of use!) was minorly degraded? There is the question of increased length (scope balance?) and also the potential of dust ingress etc. I think they are VERY useful in exploring the potential of a different (Hyperion) focal lengths. As a REGULAR way of working, I was never overly enamoured...

[Damo636]

Thanks guys. I have to admit i got a shock when I first handled one of these, they are a proper grenade! The fine tuning rings seem to be a very economical way of gaining a few extra focal lengths. I will probably eventually buy the 8 & 5mm when funds permit but for now ill go ahead and order the rings as a stopgap. Thanks again.

Damo

[John]

I felt that to some extent the image (or rather ease of use!) was minorly degraded? There is the question of increased length (scope balance?) and also the potential of dust ingress etc. I think they are VERY useful in exploring the potential of a different (Hyperion) focal lengths. As a REGULAR way of working, I was never overly enamoured...

I agree on the ease of use and dust ingress risk Chris. I was not too comfortable dismantling the eyepiece in the dark and then reassembling it again. They can help make a decision on whether to invest in alternative focal lengths, as you say.

I actually still have the fine tuning rings and find them very useful for a range of other duties such as providing a low cost extension to the 2" barrels on my Ethe eyepieces so that I can use 2" filters with them

The Tele Vue item costs around 3x as much as a fine tuning ring