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Orion Giantview BT-100 VS Celestron Skymaster 25x100 ? Thoughts?

Binoculars Celestron Equipment Eyepieces Orion Refractor
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#1 Noumenon

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Posted 03 October 2021 - 04:00 PM

So I'm thinking of getting a high-powered set of binoculars for more flexibility and portable visual astronomy to supplement my more high-powered telescope. While the telescope has some portability if desired, it does take some more time to break down and move around, etc, and easier star-hopping would be nice. I would love the extreme portability and convenience of bringing binoculars and simple alt-az mount with us while taking trips to see the outlaws in Maine, on other trips, etc, where even the trunk space the telescope would take with the whole family are not feasible.

A night could also start out with these while at home, then transition to the higher power telescope for planetary viewing.

ANYWAY -- I definitely know I want 100mm aperture for maximum light-gathering ability, and the reason why I don't just go right for the Giantviews (apart from the obviously much, much higher pricetag), is that I wonder how much benefit I would really get with switching out eyepieces for higher power, even with Barlows, etc. And are there any other significant benefits to such a system vs "regular" binoculars? Or, even still, is there some major benefit for visual astronomy with "regular" binoculars vs something like the Giantviews?

 

These are some that I've been looking at (as examples and for specs -- I'd be trying to find something like this on the classifieds, instead)...

 

https://www.amazon.c...s/dp/B07BR68XVH

https://www.amazon.com/dp/B00008Y0VU

https://www.amazon.com/dp/B076V6DTKB

 

So, yes, I'd get farrrrr more versatility with the Giantviews, but how much EFFECTIVE/USABLE versatility does one really get with this, vs just "settling" with a 25x for wide FOV?
Does anyone have any experience comparing using two binoculars like this to speak on it? Any input would be greatly appreciated!


Edited by VidiviciVeni, 03 October 2021 - 07:18 PM.

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#2 ngc7319_20

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Posted 03 October 2021 - 05:49 PM

I can offer comparison of the APM 82-90 binoscope to something like normal 15x70 binos.  The effective / useable versatility of the BT is enormous.  I mostly use them in the 60x to 100x range, but you can run them down to about 11x.  Details on Jupiter are exquisite -- dark features in bands, GRS, moon shadow transits, etc.  Star clusters are magnificent.  Deep sky M-objects are fantastic.  The 90 degree eyepieces are much more comfortable for viewing near zenith than normal binos.  

 

Downsides of BT:  You can easily spend more on the eyepieces, mount, etc., than the BT itself.  The setup is more complex and heavier obviously with a bag of eyepiece pairs, etc.  Collimation takes some attention with the BT -- the BT itself has excellent collimation, but some eyepieces need help -- eyepieces sometimes need to be rotated or shimmed to get images aligned (vs. normal bino where it is all done for you at the factory).  I end up marking the eyepieces L or R, and marking the optimal rotation, and once that is done the collimation becomes a non-issue.  You will need some red dot finder, etc., for the BT.

 

I still enjoy using the normal 15x70 binos.  The simplicity is nice.  Often there is a parallelogram mount w/ counter-weights to get steady images at 15x.   And sometimes a zero-G recliner chair.  So it is still more complex than say Canon 15-50 IS where all you need in the binos.  


Edited by ngc7319_20, 03 October 2021 - 05:49 PM.

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#3 sevenofnine

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Posted 03 October 2021 - 05:55 PM

Welcome to C/N! flowerred.gif If you complete your signature with what equipment you have and your location, you will get better answers to your questions.

 

Not many members will recommend any of the Celestron binoculars because of poor quality control. There are too many stories of multiple returns because of Q/C and collimation issues. You are lucky if you get a good pair the first time.

 

A much better place to start your search is Oberwerk.com. Same kinds of binoculars but the owner checks every pair he sells and provides a Q/C sheet. That's from the lowest to the highest priced! 

 

I would start here: https://oberwerk.com...ular-telescope/. It's a 70mm binocular telescope but it's a good one. He has 100mm models as well. I recommend getting a bino-scope over straight through binoculars. Straight through binoculars need a P-mount for you to be comfortable observing. That's a lot of complicated kit IMO.

 

Best of luck to you and your choices! waytogo.gif watching.gif


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#4 Noumenon

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Posted 03 October 2021 - 07:57 PM

I can offer comparison of the APM 82-90 binoscope to something like normal 15x70 binos.  The effective / useable versatility of the BT is enormous.  I mostly use them in the 60x to 100x range, but you can run them down to about 11x.  Details on Jupiter are exquisite -- dark features in bands, GRS, moon shadow transits, etc.  Star clusters are magnificent.  Deep sky M-objects are fantastic.  The 90 degree eyepieces are much more comfortable for viewing near zenith than normal binos.  

 

[... etc...]

At 60x to 100x do you get any chromatic aberration or other relative distortions (all things being equal)? The flexibility toward higher power is very appealing, but I wondered about the kind of distortions I'd experience through BTs vs something like the 6" newtonian I'm used to. I didn't at all expect even the 100mm BTs to pick up on details like that on Jupiter or even Saturn's rings, and hadn't even thought about DSOs...

 

I noticed that going with a 90 degree really bumps up the price and weight *a lot* due to the added complexity and nature of achieving this. While I can see the benefit, I feel like 45 degrees would be great, and while I can see the craning being an issue if looking around zenith, I suppose I could sit in a reclining chair.

 

The 11x zoom and wide field of view at these 100mm BT apertures is something I'm pretty excited about, too.

 

 

You can easily spend more on the eyepieces, mount, etc., than the BT itself.

Yeah, this is the big hangup, for me. While I can fit this in my budget and am very blessed to have enough disposable income to do so, I still try to impose limits on myself. While I could get a 25x100 for it seems a mere $200+ used, even used the BT could easily topple $1000 after everything is said and done, even used, *just to get started* and even with my SVBony redline and other eyepieces I'd consider "fine enough" at this relatively early stage of my depth into this hobby. I know it's subjective and hard to qualify -- but will I get that-much-greater of an "ooooooo" feeling of having the BTs over the regular binos to justify this 5x and more cost? And more importantly put, is that a feeling you'd consider for yourself between these two -- if having a simple, quick 25x100 vs a 100mm BT, once using the 100mm BT, considering the downsides you noted, would you often enough forego using the BTs just because of ease of reg binos at the same aperture?

 

I will undoubtedly have some 9x60s or so as easier handhelds, as well, in either case.

 

 

Welcome to C/N! flowerred.gif If you complete your signature with what equipment you have and your location, you will get better answers to your questions.

Done! Thank you smile.gif

 

 

Not many members will recommend any of the Celestron binoculars because of poor quality control. There are too many stories of multiple returns because of Q/C and collimation issues. You are lucky if you get a good pair the first time.

I see. Thank you for the heads up. I edited my post with the couple I were looking at, along with another brand (Zhumell?).

 

 

 

A much better place to start your search is Oberwerk.com. Same kinds of binoculars but the owner checks every pair he sells and provides a Q/C sheet. That's from the lowest to the highest priced!

 

I would start here: https://oberwerk.com...ular-telescope/. It's a 70mm binocular telescope but it's a good one. He has 100mm models as well.

Wow, the prices are definitely much higher than the Orion, for example. The Orion BT at 100mm is almost $1000 less -- I'm sure the quality justifies this, I just wonder if at the stage I'm in with this, if I with my more neophyte-level appreciation for optical quality, etc, can appreciate the value differential. People I talk to definitely recommend Oberwerk a lot, though. 

EDIT: I'm seeing what seem like reasonable implications around the idea that, if you have  a telescope for higher-power views and larger apertures, already (I have a 6" newtonian which is more mid-sized, but will likely get an 11" SCT in the near future once I'm done restoring the old newtonian I was given), that it may be a bit redundant to go with larger, much more unwieldy BTs like the 100mm I was looking at -- your recommendation for a BT more "grab-and-go" might supplement my versatility better. Thoughts?

 

 

 

I recommend getting a bino-scope over straight through binoculars. Straight through binoculars need a P-mount for you to be comfortable observing. That's a lot of complicated kit IMO.

 

Best of luck to you and your choices! waytogo.gif watching.gif

So far both of you seem pretty confident that the BT is the way to go. I'm definitely leaning more in that direction the more I read and as people give input.
 

This is great information so far -- thank you guys. Also, please, if you know of a thread(s) where this has been effectively covered that you can point to so I'm not asking people to reinvent the wheel, then that's great, too. I do enjoy the correspondence, though!

 

UPDATE: Some people on some other threads seem to be implying that *if* you have a telescope for deeper objects, anyway, and with the larger aperture -- maybe I really don't need to go to a 100mm, especially due to its size. That while it seems to make sense to go with a BT for the versatility, to go with a smaller aperture to maximize the widest FOV w/ the versatility of various eyepieces while also being able to handle it manually with much more ease?


Edited by VidiviciVeni, 03 October 2021 - 08:24 PM.


#5 ngc7319_20

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Posted 04 October 2021 - 12:27 AM

At 60x to 100x do you get any chromatic aberration or other relative distortions (all things being equal)? 

I should mention I have the ED glass version of the APM 82-90 ED binoscope.  I can't really say whether the Orion BT-100 would perform in the same way.   The Orion BT-100-90 claims to also have ED glass, while the Orion BT-100-45 does not say.  Also there is a wide range of what makers call ED glass, so whether the APM 82-90 ED and Orion BT-100-90 ED would perform similarly I can't say for certain.  (They appear similar in the ad photos, and are likely from the same factory.)

 

Mine have a little chromatic aberration at 100x on bright objects like Jupiter and Moon.  Sometimes I will use a cardboard mask and reduce the aperture from 82mm to 75mm or 70mm if I notice aberrations.  This is sort of a standard "trick" for improving refractor images.  There is effectively no chromatic aberration at 70mm aperture and 100x -- stars are perfect little white Airy disks.  I am using Baader Morpheus eyepieces -- there is no noticeable distortion other issues -- stars are pin point from the field center to near the field edge. 

 

Around 150x to 200x the images do start to break down and I can see some chromatic aberration.  I use 2x Barlows with the Morpheus 6.5mm or 4.5mm eyepieces to get these powers -- and I am not sure how much chromatic comes from the Barlows and how much from the BT itself.  Jupiter and Saturn are also getting dim -- it is not really enough aperture at 82mm for 200x.  That is where a 6" or 8" Newtonian would excel. 

 

At lower powers, in the 11x to 16x range, I use simpler Plossl eyepieces and star images do get a little soft at the field edges.  The Plossls are not as well corrected as the Morpheus eyepieces.

 

I noticed that going with a 90 degree really bumps up the price and weight *a lot* due to the added complexity and nature of achieving this. While I can see the benefit, I feel like 45 degrees would be great, and while I can see the craning being an issue if looking around zenith, I suppose I could sit in a reclining chair.

 

I think the market is bigger for the 45 degree version -- more sales for terrestrial use.  Also the 90 degree claims to have ED glass, wile the 45 degree does not make that claim -- that might also account for price differences.

 

With the 90 degree I use a yoke-style mount (similar to the Orion U-Mount) on a tripod with a crank-up center column.  The view is very comfortable while standing, even at the zenith


Edited by ngc7319_20, 04 October 2021 - 04:15 AM.

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#6 Rich V.

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Posted 04 October 2021 - 09:56 AM

The Orion Giantview bino telescopes are made by KUO in China; the same mfgr that makes APM's BTs.  They make achromats, "ED" and "SD" apos, also.   They make 45° and 90° versions.  Orion offers a 100mm 45° achromat as well as a 100mm ED 90° model.  They are priced according to glass type used in the objectives.

 

FWIW, here's APM's 100mm offerings; they have a wider range than the two 100mms offered by Orion.

 

https://www.apm-tele...rture-more.html

 

Any BT is easier to view through comfortably because of the neck position angled eyepieces allow.  It can be mounted on a sturdy tripod and head and used from a seated position.   A straight-through bino really needs a parallelogram mount to use it comfortably for astronomy, an added dimension of mounting complexity that needs to be addressed.

 

Good luck in your choice.

 

Rich


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#7 markb

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Posted 08 October 2021 - 12:47 PM

There is so much info above I'll restict mine to personal experience, without generalities.

 

Straight through binos? Hated them! I've had Apogee 100s, superb UO 80s and misc. 70s, and never could enjoy them. Some folks like the lounge chair plus parallelogram setup, but you are adding several hundred dollars for a quality parallelogram (ignoring self-built units, few have that skill level).

 

I bought WWII 10x80 flak binos (everything after might be better termed a BT binocular telescope), 45 degree fixed 70+ degree eyepieces, and loved them! I restored two pair and am working on a third, coated, pair that needs new objectives. Keepers.

 

I next tried an APM 100 blue tube 45 degree semi-APO, a store demo that was perfectly collimated. Loved it, too, and immediately contacted Marcus at APM to order a hand aligned pair of ED APOs. Sharper, and much more enjoyable without the violet CA.

 

I'd go as color free as you can afford, and, while 80s are nice, take the 100s if budget allows. Some folks say that is not a good idea if you have high light pollution, but I found the exact opposite for myself (20 miles from Manhattan, now 18 from central Phoenix, LED heavy).

 

Multiple the objectives by 1.4x to get a rough single tube equivalent, a well accepted conversion.

 

80s are perfectly nice, 100s are nicer, but bulk increases. Vixen BT80s are another option, but I like APMs QC on the Chinese sourced units everyone sells (except vixen?).

 

Your listed Orions look fine, I didn't read carefully to see if they use ED glass or SD glass, both highly recommended. Ordering from Amazon has the capability to return them easily and without cost, usually, if you find they have too much color, or you happen to get a pair that is not particularly well collimated or the objectives were carelessly assembled and are not as sharp as expected.

 

I use a SB T head mount (great high capacity steel bearing units, Sergio sells here and AM, but is easiest on eBay, $270  IIRC). with Orion L bracket, and a long vixen dovetail on the 'off' side, with a 1/2 pound sliding CW that makes use effortless (yes, I know I have to do a post on the simple setup). I use a siyverors tripod with a bolt swapped to 3/8-16 pitch.

 

I've read vibration issues on BT 'tray' mounts, and would never recommend a photo tripod, unless, perhaps you are buying a big dollar rigid unit with an expensive video head. There may be satisfactory ones out there, but get very specific recommendations with model numbers.

 

90 or 45? Personal preference. I'm totally sold on 45 degree BTs. No question.

 

Eyepieces? Plossls are fine, lots of solid performing inexpensive ones like Svony abound. APM UFFs are the best, made for the curved fields, with excellent AFOV. Backdoor Chinese flat field products are cheaper under other labels, but blackening and other specs vary.


Edited by markb, 08 October 2021 - 12:57 PM.


#8 Mike G.

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Posted 08 October 2021 - 01:08 PM

one thing no one has mentioned is that when using binos, even mounted, small exit pupils can be difficult to keep aligned with even small head movements.  that is, if your head is not perfectly still and you are down below 2mm exit pupil, you may experience blackouts.  for this reason, the highest mag I can pleasantly use in my APM 100's is 55x with a pair of 11mm DeLites.  If I need to go higher mag, I get a scope out.  for me, binos (even binoscopes) is all about wide field views.  typically, I run my 100's at 25x to 40x.  after 55x, my head just moves around too much for it to be a pleasant experience.


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#9 Rich V.

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Posted 08 October 2021 - 02:23 PM

Mike, do you sit or stand while viewing?  It's natural to have trouble at higher mags keeping two eyes aligned at the proper eyepoint.  I rarely stand but instead, sit on an adjustable chair with a geared column tripod and I'm definitely steadier and more comfortable because of it.  75x is still my preferred higher mag, just the same, though.

 

Rich


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#10 ngc7319_20

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Posted 08 October 2021 - 02:51 PM

one thing no one has mentioned is that when using binos, even mounted, small exit pupils can be difficult to keep aligned with even small head movements.  that is, if your head is not perfectly still and you are down below 2mm exit pupil, you may experience blackouts.  for this reason, the highest mag I can pleasantly use in my APM 100's is 55x with a pair of 11mm DeLites.  If I need to go higher mag, I get a scope out.  for me, binos (even binoscopes) is all about wide field views.  typically, I run my 100's at 25x to 40x.  after 55x, my head just moves around too much for it to be a pleasant experience.

This is a good point.  It likely varies considerably from observer to observer depending on max eye pupil size, eye aberrations, and steadiness.  But yes, it can take some effort to align the bino-scope exit pupils with both your eye pupils, especially at the higher powers.


Edited by ngc7319_20, 08 October 2021 - 02:52 PM.


#11 Mike G.

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Posted 09 October 2021 - 02:03 PM

Mike, do you sit or stand while viewing?  It's natural to have trouble at higher mags keeping two eyes aligned at the proper eyepoint.  I rarely stand but instead, sit on an adjustable chair with a geared column tripod and I'm definitely steadier and more comfortable because of it.  75x is still my preferred higher mag, just the same, though.

 

Rich

I do both, I have a Vestil adjustable chair I use with the binos and scopes. But besides being 66 y.o., I also have arthritis is my cervical spine. So there’s that…. But even in a zero gravity chair with hand held binos resting on my forehead, I still prefer them with exit pupils >3mm



#12 Dpasqa

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Posted 25 November 2021 - 12:52 PM

Just my little two cents, I bought the Orion BT-82’s. I couldn’t justify having to spend another $400+ for a heavy duty mount and tripod required for the 100’s. My BT-82’s work fine on my Paragon Plus Heavy Duty tripod I already owned. Although I’m sure you can see more detail with the 100’s, I’m happy with what I can see with the 82’s. I still can see the cloud bands on Jupiter and the rings separated on Saturn which makes me happy to see. If I want larger views I can switch to my XT8 Dob. Thing I love about the BT’s is how easy it is to setup and find things. The dob is a pain getting it outside and setup cause of the bulk and weight, where I get the BT’s are on the the tripod in seconds. So if you don’t want to deal with the higher cost of the 100’s and a heavy duty tripod and mount, you might consider the 82’s. You’ll be surprised what you can see. 


Edited by Dpasqa, 25 November 2021 - 02:16 PM.

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#13 erin

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Posted 28 November 2021 - 10:15 AM

Just my little two cents, I bought the Orion BT-82’s. I couldn’t justify having to spend another $400+ for a heavy duty mount and tripod required for the 100’s. My BT-82’s work fine on my Paragon Plus Heavy Duty tripod I already owned. Although I’m sure you can see more detail with the 100’s, I’m happy with what I can see with the 82’s. I still can see the cloud bands on Jupiter and the rings separated on Saturn which makes me happy to see. If I want larger views I can switch to my XT8 Dob. Thing I love about the BT’s is how easy it is to setup and find things. The dob is a pain getting it outside and setup cause of the bulk and weight, where I get the BT’s are on the the tripod in seconds. So if you don’t want to deal with the higher cost of the 100’s and a heavy duty tripod and mount, you might consider the 82’s. You’ll be surprised what you can see. 

To your last point, I have the OB 70mm BT and am very happy with what they show me and how portable they are.

 

Also, for the OP, I want to point out that you have to buy the cases for the Orion BT’s separately and they are pricey. Oberwerk’s BT’s come with the case included in the listed price. I wasn’t sure if you were aware.

 

Good luck!


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#14 Dpasqa

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Posted 28 November 2021 - 10:42 AM

To your last point, I have the OB 70mm BT and am very happy with what they show me and how portable they are.

 

Also, for the OP, I want to point out that you have to buy the cases for the Orion BT’s separately and they are pricey. Oberwerk’s BT’s come with the case included in the listed price. I wasn’t sure if you were aware.

 

Good luck!

Yes you have to buy the case for the Orion, but with that said, the price is close. I guess if you don’t want the case Orion is better. I like the Gray that OB offers more than the Orion white but color doesn’t change the view or value. I’ve always bought Orion products so I went that way.

 

BTW, I did a review in the BT-82 case. I was disappointed in that the holes for the eyepieces are too large and deep for most eyepieces. I had to put filler foam rubber so my eyepieces, they didn’t design this with real world use in mind. I can’t imagine what eyepieces I would use that are 5 to 6” long. For people that use Plossl eyepieces it would be a hassle since most of them would fall into the holes and be difficult to get out, they could have used smaller holes and a few more if they thought it through. So for $300 I shouldn’t have had to jerry rig the darned thing. 


Edited by Dpasqa, 28 November 2021 - 10:44 AM.

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#15 erin

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Posted 28 November 2021 - 12:20 PM

What a bummer about the Orion cases…most of my pairs are smaller eyepieces too. Thanks for mentioning that!



#16 Astrogoss

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Posted 28 November 2021 - 08:49 PM

I own the Oberwerk BT 100 and 70 XL-ED BT's and couldn't be happier with them.


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#17 oldmanrick

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Posted 28 November 2021 - 09:48 PM

one thing no one has mentioned is that when using binos, even mounted, small exit pupils can be difficult to keep aligned with even small head movements.  that is, if your head is not perfectly still and you are down below 2mm exit pupil, you may experience blackouts.  for this reason, the highest mag I can pleasantly use in my APM 100's is 55x with a pair of 11mm DeLites.  If I need to go higher mag, I get a scope out.  for me, binos (even binoscopes) is all about wide field views.  typically, I run my 100's at 25x to 40x.  after 55x, my head just moves around too much for it to be a pleasant experience.

I have found that "stick time" or practice, plus working up through progressively smaller exit pupils will eventually go a long way towards better comfort when using big binoculars at higher powers.  

 

Also be sure to get as comfortable as you can.  As Rich said above, an adjustable observing chair and elevating geared center column in a solid tripod are also great aids to more comfortable viewing, especially at higher powers.

 

Rick




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