Hyperion vs BST Starguider

[MimasDeathStar]

Hello all

I have searched for this a few times but I haven't found any recent discussion so am going to risk floating it again!

I've got an f5 150mm reflector. I splurged a bit and got a 21mm hyperion and, after the initial shock of how big it is, am really enjoying using it! I have a 26mm plossl that covers almost the exact same area of sky so I'm able to reasonably well compare the two. Centre sharpness, contrast and definition are noticeably better on the Hyperion but I do notice quite a whopping dropoff in sharpness from about 80% out.

I bought the hyperion mainly for its massive eye relief. I have mild astigmatism and wear glasses. Unfortunately I still cant really get close enough with glasses to see the whole field stop so with that in mind I'm still observing "sans specs" and now wondering whether the BST starguiders may be comparable? I'm aware they have slightly less eye relief and FOV but they are literally half the price and seem to garner stellar reviews from all corners.

Has anyone ever done a direct comparison of these two?

[Louis D]

The 25mm BST is not very good at f/6 from 50% out.  It does have plenty of eye relief for eyeglass wearers.  The 24mm APM UFF is much more consistent across the field and is quite usable with eyeglasses.  If you expand the FOV image, you'll see that the BST tends to blur out sooner than the HD-60 and much sooner than the UFF.

[MimasDeathStar]

Thats interesting thanks, maybe I will stick with Hyperions then

[bomberbaz]

6 hours ago, MimasDeathStar said:

Thats interesting thanks, maybe I will stick with Hyperions then

I have brought this up a few times before in other threads.  I have pretty bad astigmatism but find that I can use eyepieces that give a exit pupil of 3mm or less without my glasses. 

you may find it different but I think it could be worthwhile for you to try and see if you find it the same.  It will lead you to a different world, especially at high power viewing.  Well that's my own findings.

[MimasDeathStar]

On 15/07/2020 at 23:58, bomberbaz said:

I have brought this up a few times before in other threads.  I have pretty bad astigmatism but find that I can use eyepieces that give a exit pupil of 3mm or less without my glasses. 

you may find it different but I think it could be worthwhile for you to try and see if you find it the same.  It will lead you to a different world, especially at high power viewing.  Well that's my own findings.

Thankyou - yes I think it is more or less manageable without glasses after all which is handy!