Question: UO Ortho vs. Baader Hyperion??

[Mark Moyer]

I have various astronomy interests, but up at/near the top is faint galaxies. Faint minor moons is also up there a ways.

Because of this, I followed Alvin Huey's advice (on one of his Faint Fuzzies pages) and got a 6mm University Optics H.D. Ortho. The idea was to get maximal transmission. There is very little transmissivity data out there, but it seems like this EP has great transmissivity (if nothing else, Huey's advice makes me think so).

Of course, it has a fairly small fov. And since I don't have tracking mounts, I've found that often it is a pain in the behind to try to stay on an object. I'll switch to the Ortho and sometimes loose the object then. But if I find the object, I watch it sweep through the fov, staring intently (for the very faint ones), and keep repeating over and over to try to find whatever I'm trying to find (whether it's the object itself or some feature of it or ...). But in the process I often lose the area and have to switch back to a different EP to find it again and then start all over. And if it's quite cold or I'm tired or whatever, then this can become even more frustrating.

Oh, I should mention which scopes these are used in. I primarily use an 18", f/4.5. But I also use a 12" SCT (f/10).

So it sure would be nice to have a wider fov. But in addition, how visible a faint thing is depends upon magnification too. So my thinking is, if I went to an EP with higher magnification, then this will partially make up for the lower transmission of the new EP. Anyway, I'm thinking of getting a Baader Hyperion 5mm (a used one is on sale). These are advertised as having great coatings, but they have 8 lenses. I've come to believe that the coatings are more important than the number of lenses, but 8 is still 8 and the UO Orthos no doubt have great coatings as well (better?). 5mm with 68 degree fov would give me substantially larger fov, but I'm not sure if the loss of transmissivity will hinder the faint fuzzy finding some.

Before making any decisions I thought I'd ask y'all if you had any insights. Any advice is most welcome -- thanks!

[stargazer769]

Well, I have the Tak Abbes, have used the UO and KK Abbes, and have an old set of Hyperions in storage. I will say there's no contest between the Abbe and Hyperion, especially on lunar/planetary/solar viewing or on double and variable stars. The Abbe will be much sharper, a bit brighter due to lack of scatter, and no coma; inherent coma is one thing I seem to remember about the Hyperion view, slightly bloated stars. Also, color accuracy is much better in the Abbes IMO. For your dob, you're going to see lots of astigmatism on the Hyperions too.

Did I mention the Abbe will be much sharper with better color and lack of scatter? Just checking.

Don't get me wrong, the Hyperions are a decent eyepiece for the money if you get them on sale, but they haven't improved on the design or glass used and have been surpassed by newer offerings, such as ES if you can find them on sale. As it is now, I see them as too expensive for the performance.

Let me just add that if you're a CN member and have read my posts on my Baader prism diagonal I just bought, you'll see I'm not at all happy or satisfied with Baader QA or the level of their products currently. $440-500 for a diagonal, it should be near perfect, not so far out of alignment the collimation bullseyes are nearly an inch off center at the objective, not to mention a prism that rattles in the housing. Sorry, no more Baader for me.

[not_Fritz_Argelander]

I had the Baader Hyperions and found the corrections and coatings not up to the standard of TV Panoptics and yes the price difference is worth it. The BCO Orthoscopics and my new set of Fujiyama Orthoscopics are superior to the TV Panoptics in contrast especially in rendering fine internal details in faint fuzzies.

When I need wide field on my Z12 I use TV Panoptics and Delos. (I loathe 82 degrees AFOV and ejected my Naglers btw.) I've used Orthoscopics on my Z12 and the Delos are almost as contrasty on planets. Yes TV Delos is almost as contrasty as my Orthoscopics!

You might find the Baader Hyperions ok on slow scope like your Meade. They're fine at f10. The are worse at f5. Although Orthoscopics are supposed to be better at slower f ratios too I see no problem with mine at f5.

[jerryTheC]

Unless you have amazingly good seeing, 5mm is going to be over the top for magnification in the SCT. Where I am, 12mm is the shortest fl eyepiece I usually use in my 11" SCT, and it's extremely rare that I've been able to use an 8mm.

The Hyperions work well in slower scopes, though some users say they don't perform as well in fast scopes. (Personally, I prefer the Vixen LVWs - I like them, while I can take or leave the Hyperions; nothing wrong with them in an SCT, but I get on much better with the LVWs - fortunately, I managed to pick mine up for a very good price used).

While going to a higher magnification will dim the sky background some, it's also going to dim the DSO - you're spreading the same amount of light over a larger area. If you're trying to keep the same brightness with a lower transmission eyepiece, you'd usually reduce the magnification not increase it - that way you get a smaller but brighter image.

A larger FOV helps a lot with an undriven mount. If your budget will stretch to it, you might want to consider keeping an eye out for a used 82° AFOV eyepiece, but the 68° ones are still a nice improvement.

[bpm990d]

Spend some more money and get the Morpheus line.

B

[Lowjiber]

Mark, check your PM's... I just sent you a PM.

[j.gardavsky]

Hello Mark,

there is not much left to compete on the transmission of light and on contrast with your UO 6mm ortho.
You can of course try the Baader BCO 6mm, which has about 50° AFOV, and the HT (high transmissivity) multicoatings.

For the very high magnifications I am using the BCO 6mm and the Pentax XW 7mm, Pentax+ / smc PENTAX XO smc PENTAX XW
The reason for the Pentax XW 7mm has been its high transmissivity in blue, due to the SMC multicoatings, which has been claimed(?) as being similar to the Zeiss multicoatings. In spite of it, the Pentax XW 7mm with its 8 lenses loses against the BCO 6mm on the star counts in the clusters.
The transmissivity in blue is important, as most of the galaxies are in fact blue. Moreover, when hunting the nebulae, you need the maximum transmissivity over the OIII doublet and over the blue Balmer spectral lines: H-Beta, H-Gamma, and eventually also H-Delta when you take out your 18" Dob.

At f=10mm, I take the Baader BCO and the Swarovski SW 10.2mm, - each has its own DSOs or details inside.
At longer focus, the Zeiss (Diascope) and the Leica (Televid) wide 65° - 68° eyepieces can be hardly beaten on the transmission of light and on the contrast, and my feeling is, they perform even better than the Tele Vue Plössls.

Hoping this helps,

JG

[j.gardavsky]

Hello Mark,

I have finally retrieved the transmission values for the eyepieces,
A m a t e u r a s t r o n o m i e . c o m/T i p s

Best,

JG

[not_Fritz_Argelander]

Hello Mark,

I have finally retrieved the transmission values for the eyepieces,
A m a t e u r a s t r o n o m i e . c o m/T i p s

Best,

JG

Thanks so much for this. Now I have objective measurement confirmation that fewer lenses are better and that I am not "just imagining" that my Orthoscopics outperform more complicated designs on DSOs.

[Mark Moyer]

Many thanks, everyone! Some of the mentioned EPs are out of my price range, but you've provided me with a lot of useful information to digest. Hopefully others can use this too in making their decisions.