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Baader 30mm Scopos- First Light!

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#1 erik

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Posted 13 February 2007 - 07:50 PM

After a week of clouds and rain, it finally cleared up just enough last night to get the scope out for a couple of hours. Conditions were poor, as areas of clouds were moving across the sky rather quickly. This made for some difficult viewing, but I still got some results that I felt were worth sharing.

The Baader 30mm Scopos is impressive to look at. It's 6" tall, and weighs in at about 25 ounces. It's an 8 element design, with at least two of the elements contained in the chrome barrel portion of the eyepiece- in other words, there's a lot of glass in this baby! However, it's positively puny compared to its mammoth 35mm counterpart, which weighs over 38 ounces! :shocked: ...Because of the excellent performance in the 35mm Orion Stratus I recently got to try out (which is reportedly similar or identical to the Scopos), I was excited about the 30mm version.

I mainly compared the 30mm Scopos to my 32mm Agena SWA. My thought going into it was that the Scopos would have much better edge correction than the Agena (not that the Agena is bad at all, BTW), and it did, in some ways- read on:

*The Scopos does have good correction for astigmatism in my f/4.5 dob with a paracorr. I'd say that the outer 5% had noticeable astigmatism. The Agena SWA shows astigmatism from about 20% away from the edge, with the outer 10% getting rather nasty.

*The Scopos, however, suffers from something else: field curvature. About 10-15% from the edge, stars appear out of focus. The 4 main components of the trapezium in M42 were JUST visible as separate stars when viewed at the edge without refocusing.

*Stars are "tighter" in the Agena SWA. Of course, this may be partly due to the magnification difference, which, I believe is more substantial than the 2mm difference would suggest. I think that the 30mm Scopos is actually closer to 28mm in terms of magnification. I think this based on owning several ep's in this magnification range, and it's just my personal opinion- I might be wrong. In any case, I felt the views in the center of the fov were slightly nicer through the Agena SWA.

*There is a very small amount of pincushion distortion. Maybe a bit more than the Agena, but still not much. Definitely much less than the 35mm Panoptic.

*The AFOV is wider in the Agena. The Scopos seems to be about 65 degrees, while the Agena is noticeably wider. TFOV is also wider, of course, but this is partly due to the magnification difference. To help verify this (without doing any math! :grin: ), I compared the Scopos, Agena, and 24mm Panoptic by pointing the scope to an area of the sky covered in clouds. This way, no stars would play tricks with my eyes- just a black field stop against the grey/white background. I'm not sure if this is considered a "valid" test, but I'm pretty confident that the Agena was widest, followed by the 24mm Pan, and finally, the Scopos, which was very close in AFOV to the Pan- but not 70 degrees as advertised.

*The Scopos is very nearly parfocal with the 24mm Panoptic. This is nice when switching ep's, and no change is necessary on the paracorr.

*The Scopos is built well, with a nice rubber grip, and an eyeguard that, while a bit stiff, was much easier to use than the Agena SWA's very stiff eyeguard. Rolling the eyeguard down on the Scopos revealed some blacking out, but the whole fov can be easily taken in with the eyeguard up. For eyeglass wearers, the adjustable eyeguard will be very useful.

...To summarize, I'm not quite sure what to think about the 30mm Scopos. It does some things well (like correcting astigmatism), but in many ways, the Agena SWA, which is almost 1/3 the price, beat it. Neither is as good as a real "premium" eyepiece, and to be honest, I'm slightly dissapointed in the Scopos' performance overall. The 30mm is definitely not as good as the 35mm (at least the Stratus version), but the 35mm is not an option for me because of the weight. Of course, these are ep's that cost under $200, so for the price, they're not bad. But definitely not a Panoptic. I guess there's still no free lunch with low power, widefield ep's- despite the recent improvements in the lower priced alternatives. I'm going to continue to evaluate the Scopos, hopefully under better conditions, but in the end, I'm not sure whether it's my final solution. :)

#2 Chopin

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Posted 13 February 2007 - 08:33 PM

And there it is folks! :grin:

Thanks for taking the time to post your initial evaluation of the edge performance of the 30 Scopos, Erik. Maybe with some better skies, you'll get an idea on the contrast/transmission capabilities. Until then, your edge measurements seem like a good starting point for anyone willing to look at one of these.

Much appreciated sir. :bow:

#3 erik

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Posted 13 February 2007 - 08:41 PM

And there it is folks! :grin:

Thanks for taking the time to post your initial evaluation of the edge performance of the 30 Scopos, Erik. Maybe with some better skies, you'll get an idea on the contrast/transmission capabilities. Until then, your edge measurements seem like a good starting point for anyone willing to look at one of these.

Much appreciated sir. :bow:

Hi Jason, thanks! Yep, the conditions were too poor to make a judgement on transmission. I tried, but the clouds were moving through too fast. Also, due to the difference in magnification between the 32mm and 30mm ep's, I'm not sure it would be a fair comparison. FWIW, the light throughput seemed fine. Stars were a bit "warmer" looking through the Scopos, but more pinpoint through the Agena. Saturn had a slightly darker hue through the Scopos as well. ...But of course, that could've just been a cloud rolling through the fov... :grin:

#4 csa/montana

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Posted 13 February 2007 - 09:26 PM

Erik: Thank you for an in-depth report on this eyepiece. Your honesty & experience is very valuable to others reading this. I do believe this is the first report!

Again, thanks!

Carol

#5 skyview

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Posted 13 February 2007 - 10:24 PM

Thanks for the report, too bad about the free lunch.

I'm leary about a number of these new EPs, especially since I have an f/5.4 refractor. So anyone brave enough to try them out and fill the rest of us cowards in gets a gold star in my book.

#6 Hal_Coward

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Posted 13 February 2007 - 11:06 PM

I'm leary about a number of these new EPs, especially since I have an f/5.4 refractor. So anyone brave enough to try them out and fill the rest of us cowards in gets a gold star in my book. [/quote]

Same goes for me and my fast reflectors. Two gold stars from me. Thanks!!

#7 erik

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Posted 13 February 2007 - 11:37 PM

Well, I had it out again this evening under much better conditions. I'm sending this eyepiece back. It has a subtantial amount of field curvature, which mostly negates the benefit of good astigmatism correction. In addition, it doesn't "snap to focus" like the Agena, and stars aren't very pinpoint. I'm hoping that they're not all like this. In any case, I'm going to get something different. Maybe something with green letters...

#8 ezrider23

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Posted 13 February 2007 - 11:48 PM

Maybe something with green letters...


26mm T5 :whistle:

#9 Lew Zealand

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Posted 14 February 2007 - 01:08 AM

Thanks for the first light report and follow-up, Erik! Your description of the field curvature is a definite deal breaker for me (and apparently you!), I can live with some astigmatic stars at the edge at faster focal ratios if there is no field curvature. That and the tighter stars in the Agena 32mm are making me consider it very seriously. And I'll be using it at f/6 and f/10 - both slower than your scope. Any idea if the 38mm Agena is as well corrected as the 32mm??

#10 Rick Woods

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Posted 14 February 2007 - 12:27 PM

Maybe something with green letters...


26mm T5 :whistle:

31mm T5 :wron:

#11 Scanning4Comets

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Posted 14 February 2007 - 12:38 PM

30mm T7 :whistle: :lol: ;)

#12 naglertized

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Posted 14 February 2007 - 03:45 PM

28mm. WO UWAN, a little more magnification the same if not larger FOV.

#13 Scanning4Comets

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Posted 14 February 2007 - 05:41 PM

Erik...why don't you try the 30mm XW and give us the full scoop?

#14 erik

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Posted 14 February 2007 - 06:39 PM

The 30mm XW is a bit too expensive for what I want, given that the fov is 70 degrees, and not 82. The UWAN is out of the question because of the weight, as is the 31mm Nagler, Meade 30mm UWA, etc. The 26mm Nagler is probably the best solution, but I wish the 31mm was lighter in weight. I owned the 31mm, and balance was a big problem. I'd also rather not spend $600 on one ep, but I'm also a bit tired of messing with the less expensive alternatives. I'm really dissapointed with the Baader- it's nothing like the 35mm Stratus, or most of the 1.25" Stratus for that matter (in terms of performance).

#15 erik

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Posted 14 February 2007 - 06:41 PM

Thanks for the first light report and follow-up, Erik! Your description of the field curvature is a definite deal breaker for me (and apparently you!), I can live with some astigmatic stars at the edge at faster focal ratios if there is no field curvature. That and the tighter stars in the Agena 32mm are making me consider it very seriously. And I'll be using it at f/6 and f/10 - both slower than your scope. Any idea if the 38mm Agena is as well corrected as the 32mm??

Hi Tom! I haven't used the 38mm, but it's been reported that it may be identical to the Burgess SWA, which have received some good reviews...

#16 square_peg

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Posted 14 February 2007 - 10:16 PM

30mm T7 :whistle: :lol: ;)



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