9mm shootout!

[Ags]

With the 28mm and 14mm fine tuning rings in place, my Hyperion 17mm acts as a 9.2mm eyepiece. That begs the question of how it compares to my 9mm TS Planetary (TMB clone). I have tried out these two eyepeices in the F13 mak in which they yield a magnification of approximately 150x.

I tried them out at daytime first. Colors seemed slightly more vivid in the Hyperion, but the view was very difficult with blackouts and kidneybeaning. It was impossible to see the full field of view of the hyperion for some reason (the edges were persistently blacked out) - a comparison with the 24mm showed no issues with seeing the full 68 degree field, so I think the problem was caused somehow by the fine tuning rings. Given the difficulty of getting my eye in the right position, it was hard to judge but I had the feeling the TS Planetary was giving me the same if not larger field. The TS was certainly showing a more usable field.

Another odd thing was that the Hyperion was giving significantly more magnification that the TS Planetary, even though in theory it should give slightly less.

Tonight I had a chance to try out the eyepieces in darkness. I tried the double double first. The TS Planetary managed to split all 4 stars, but not quite cleanly. When I was less experienced, I could not see the split with the TS 9mm.

The hyperion managed to split the stars cleanly - giving as clear a view as my 6mm TS Planetary, less magnified but cleaner and sharper.

This was however on axis. I tried splitting the stars at the edge of the field and got different results. The stars stayed more or less split in the TS Planetary when the double double was positioned at the edge of the field with only a slight degradation. In the Hyperion the problems I was having in daytime with the field of view reemerged and I found I had to contort to see the edge of the field of view. This meant putting my eye at an angle to the eyepiece, which I think resulted in astigmatism smearing out the stars and making them completely unresolveable. In the Hyperion, the double double was only good in the middle 70% of the field.

I then tried a faint target - M57. It is quite bright but the eyepieces were magnifying it by 150x so it was faint enough, especially as light pollution and transparency was particularly bad on the night. The nebula looked similar in both eyepieces, with a slight edge going to the Hyperion. The Baader eyepiece seemed to give just a bit more contrast.

In conclusion, my 9mm TS Planetary can relax - it is not going on the transfer market just yet. The Hyperion is not breaking into the planetary league and will be relegated to DSO duties, operating at 13mm and 17mm, where it performs perfectly.

[Nexus 6]

Excellent read, if you were using the 4se then thats really good performance....shows the capabilites of the scope as well as the ep's... even more so if you have to deal with some bad lp

[Ags]

Thanks - I was using the 4SE. It's a brilliant scope on tight doubles and anything else that needs a bit of magnification.

[Damo636]

Every time a tuning ring is added to a Hyperion the field stop diameter is slightly decreased. I use the rings occasionally with the 8mm but only one ring at a time to make either 5 or 6mm focal lengths. Both together and it looks like a chimney hanging on the end of the focuser! I recently compared a 5 and 6mm TMB planetary to the 8mm Hyperion and fine tuning ring combo and found the latter gave the better views of Saturn. Even with the extra glass the Hyperion produced a brighter image with much better contrast. To my eyes i find they are sharp out to about 85% of the fov at f6.

[Ags]

Yes I thought that both FTRs together would push the EP to its limits. I would agree the field of view is diminished but not in a pleasant way (like a reduced field stop) but more as an intrusive blackout effect.

With both FTRs the eyepiece looks like a monster - when I get my camera I'll post a comparison pic. It makes me think twice about buying a long EP like a Speer-WALER.

I think the Hyperion would beat the TS Planetary (in optical terms) on planets based on its performance with double stars. But the TS was nicer to use and only a little less performant. I will try to remember to update the thread when a planet comes into view - that might be a while!

Given the fiddliness of eye placement, and the unpleasantness at the edges, I don't think I would like the Hyperion on the Moon at 9.2mm.

[Damo636]

Using both fine tuning rings with the 17mm reduces the field stop diameter from 20.9mm to 12.1mm. This might explain the blackouts and the need for more accurate eye placement but not sure. I have read on here that the TS planetary clones are actually sharper than the TMB planetary's so not surprised with your findings.

[Ags]

Thanks Damo - where did you get that information on field stop dimensions, by the way?

EDIT: I think I get it now - the field stop is behind the smythe, so with greater spacing between the smythe and the field stop a narrower cone of light must pass through the field stop.

[Damo636]

I found the information in a pdf here.

Baader Planetarium - pdf downloads in englisch language

I think its the part one for visual.

[Ags]

Finally got round to posting a size comparison...

Hyperion: I am the god of nine millimetire!

TS Planetary: Is it raining yet?

[cs1cjc]

In my experience, the Barsta ED (HR Planetary as I understand it) 9mm has more glare round bright objects and less contrast than the similar (the design is not the same in this focal length) TMB Planetary II which in turn is not as good as a (9mm (Antares similar BGO?) ortho.

[Ags]

...and I've heard that the TS Planetary is one of the better TMB clones...

I finally tried out the Hyperion at 9mm on a planet under good seeing and compared it to both my 6mm and 9mm TMB clones. On planets the hyperion is a clear winner. Much more detail on Jupiter was apparent and contrast was much better due to the total absence of internal reflections. The hyperion at 9mm (with two tuning rings) has given me the best views of Jupiter this season.

Due to the great contrast and absence of reflections, the viewing was much more immersive with the hyperion versus the TMBs. I could forget I was looking through a telescope.

This upsets all my long-term EP plans. It looks like I will have to invest in premium planetary EPs after all.

[great_bear]

BGOs - that's what you need - it won't break the bank

[Ags]

Yes BGOs will have the same excellent multicoatings as the hyperions, as well as far fewer glass-air surfaces. But I am thinking of getting a fast telescope so BGOs don't come in sufficiently short focal lengths. I'm thinking of a TV 3-6mm zoom instead. Not sure how to free the funds from the joint account though...

[Ags]

My hopeful imagination had chopped off 33% of the price of that TV zoom... I may have to make do with the TS planetaries for a while longer. Or get a 5mm hyperion and use the FTRs to tune it to the likely mag for planets (higher for mars/saturn, lower for jupiter). It's not like all of them are in the sky at the same time!

[great_bear]

My hopeful imagination had chopped off 33% of the price of that TV zoom...

They don't come up "used" very often either!

[Ags]

A third party has joined the shootout - a rattly old Speer WALER 10mm (but we know it is actually 9.4mm). It is much more compact than the hyperion with two tuning rings - it is actually quite compact. Perhaps because of the reputation for SpW eyepieces being so long and unwieldy, I had expected an optical bazooka, but it is a pretty normally shaped and sized EP.

On axis the Speers is at least equivalent to the TS Planetary, with less reflections around the planet, but there is a faint faint radial ray scattering off from the planet through the middle of the view, only visible with averted vision. I have the sense that the Speers gives a touch more definition to the planetary detail than the TS Planetary.

Compared to the Hyperion, I think the hyperion shows a little more detail and controls reflections much better.

Off axis, the Speers shows noticeable fringes of false color on Jupiter from about 50% off axis.

The Speers was awesome on the moon, but it is full moon tonight so I'm snow-blind in one eye now. Would I give my left eye for the view? I did... :-)

UPDATE: Io (I think) has now crossed Jupiter's limb and can be seen clearly in the Hyperion and Speers shining against the darkened limb of Jupiter. In the TS Planetary the moon is barely visible - I would not be confident of spotting it had i not first found it in the other EPs. The moon is clearest in the hyperion.

[Ags]

So, in conclusion, the hyperion beats the Speer WALER by a little bit, with the TS Planetary in third place. At first I struggled with the truncation of the view in the hyperion with both fine tuning rings, but now I have learned to accept the approx 60 degree field and I would say it is not an issue.

I will be using the Hyperion for the rest of this Jupiter opposition. At least on the good evenings (I'm not sure I want to mess too much with the fine tuning rings - I might let dust into the innards of the hyperion).

The Speer WALER is nice too, but I think its strengths are more on lunar and DSO viewing, but it is perfectly servicable for planetary views. When viewing the moon at 150x, the Speer shows nearly the complete moon.

[twotter]

Interesting thread. I really must start using my FTRs