Mr. Bill
Carpal Tunnel
  
Reged: 02/09/05
Posts: 2757
Loc: Just passing through.....
|
|
Just talked to Mike at Astronomics about new Vixen 125mm binoculars that will take standard 1 1/4 eps. Word is that the price will be around $4K, but that will include the fork and mount and 22mm eps so you are looking at a complete package.
It is scheduled to be available in the US in August.
With my 24 Pans assuming f/5, it would give 26x at 4.8mm exit pupil.....perfect for MW scanning!
Needless to say, Mr. Bill is watching developments with GREAT interest.
-------------------- 10x50 Fujinon FMT-SX binos
15x70 AP binos + Paragon p-mount
Oberwerk 100BT 45 degree + Hercules fork mount
120mm f/5 Orion achromat + Moonlite focuser
140mm f/5.7 Vixen NeoAchro Petzvel refractor
150mm f/6.5 Antares achromat
150mm f/8 homemade achromat....EE Barnard MW Sweeper
8 inch newt with f/5 Swayze mirror
10 inch f/4.7 Orion newt + Paracorr
15 inch f/5 Discovery split tube
35mm Pan, 26mm Nagler, 17mm Nagler, 13mm Ethos, 8mm Ethos
Member IDA
Edited by Mr. Bill (06/25/08 03:01 PM)
|
milt
sage
   
Reged: 09/13/04
Posts: 429
Loc: Arizona
|
|
Hi Bill,
Are these really new, or the same old 125mm f/5 achro's that Vixen has been selling for years? If so, my guess is that they are going to have a fair amount of color. This may not bother you at low magnifications, but if it proves to be objectionable at high powers the advantage of interchangeable ep's is somewhat negated.
Milt
|
Mr. Bill
Carpal Tunnel
  
Reged: 02/09/05
Posts: 2757
Loc: Just passing through.....
|
|
Quote:
Hi Bill,
Are these really new, or the same old 125mm f/5 achro's that Vixen has been selling for years? If so, my guess is that they are going to have a fair amount of color. This may not bother you at low magnifications, but if it proves to be objectionable at high powers the advantage of interchangeable ep's is somewhat negated.
Milt
My info says they are a new design....I guess we'll have to wait and see. I hope for better coatings and perhaps a third objective element for field flattening.
The advantage to me of interchangable eps is that I can select the finest available (IMO the 24 Pans are at the top of the list for low power, the 14mm Denks for medium). The oculars always seem to be the weakest link and heavily contribute to the field edge distortions, even on expensive binos.
-------------------- 10x50 Fujinon FMT-SX binos
15x70 AP binos + Paragon p-mount
Oberwerk 100BT 45 degree + Hercules fork mount
120mm f/5 Orion achromat + Moonlite focuser
140mm f/5.7 Vixen NeoAchro Petzvel refractor
150mm f/6.5 Antares achromat
150mm f/8 homemade achromat....EE Barnard MW Sweeper
8 inch newt with f/5 Swayze mirror
10 inch f/4.7 Orion newt + Paracorr
15 inch f/5 Discovery split tube
35mm Pan, 26mm Nagler, 17mm Nagler, 13mm Ethos, 8mm Ethos
Member IDA
Edited by Mr. Bill (06/25/08 03:47 PM)
|
EdZ
Professor EdZ
   
Reged: 02/15/02
Posts: 12562
Loc: Cumberland, R I , USA42N71.4W
|
|
These would be the Vixen 125 that I saw at NEAF. They were displayed at NEAF with what is supposed to be a fixed power 30x eyepiece. At that time I called the Vixen rep over to the display and I pointed out that the exit pupil SHOULD be 4.2mm. I showed him that the exit pupil was 3.8mm. The cause of thee reduction was not clearly apparent, but he agreed the reduced exit pupil was apparent.
Causes could be several:
..perhaps the eyepieces were not a focal length that produced 30x but they were giveing 33x.
..there may have been baffels intruding into the light cone path before the light reached the prisms
..the prism aperture could be sized such that the entire light cone cannot pass.
Either one or more of the above is reducing the exit pupil on this big binocular.
edz
-------------------- Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
|
Mr. Bill
Carpal Tunnel
  
Reged: 02/09/05
Posts: 2757
Loc: Just passing through.....
|
|
Quote:
These would be the Vixen 125 that I saw at NEAF. They were displayed at NEAF with what is supposed to be a fixed power 30x eyepiece. At that time I called the Vixen rep over to the display and I pointed out that the exit pupil SHOULD be 4.2mm. I showed him that the exit pupil was 3.8mm. The cause of thee reduction was not clearly apparent, but he agreed the reduced exit pupil was apparent.
Causes could be several:
..perhaps the eyepieces were not a focal length that produced 30x but they were giveing 33x.
..there may have been baffels intruding into the light cone path before the light reached the prisms
..the prism aperture could be sized such that the entire light cone cannot pass.
Either one or more of the above is reducing the exit pupil on this big binocular.
edz
The 125mm model that you saw at NEAF is what is currently on the Vixen website ; the 125mm binocular I'm talking about with interchangable 1 1/4 inch eps is not yet released in the US. Supposed to be two entirely different animals.
We'll see...
-------------------- 10x50 Fujinon FMT-SX binos
15x70 AP binos + Paragon p-mount
Oberwerk 100BT 45 degree + Hercules fork mount
120mm f/5 Orion achromat + Moonlite focuser
140mm f/5.7 Vixen NeoAchro Petzvel refractor
150mm f/6.5 Antares achromat
150mm f/8 homemade achromat....EE Barnard MW Sweeper
8 inch newt with f/5 Swayze mirror
10 inch f/4.7 Orion newt + Paracorr
15 inch f/5 Discovery split tube
35mm Pan, 26mm Nagler, 17mm Nagler, 13mm Ethos, 8mm Ethos
Member IDA
|
EdZ
Professor EdZ
   
Reged: 02/15/02
Posts: 12562
Loc: Cumberland, R I , USA42N71.4W
|
|
Quote:
The 125mm model that you saw at NEAF is what is currently on the Vixen website ; the 125mm binoculars I'm talking about with interchangable 1 1/4 inch eps are not yet released in the US. Supposed to be two entirely different animals.
We'll see...
The comment from the rep as we stood there and discussed the 125 was
we will soon be making this model available to take interchangable 1.25" eyepieces.
edz
-------------------- Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
|
Mr. Bill
Carpal Tunnel
  
Reged: 02/09/05
Posts: 2757
Loc: Just passing through.....
|
|
Quote:
Quote:
The 125mm model that you saw at NEAF is what is currently on the Vixen website ; the 125mm binoculars I'm talking about with interchangable 1 1/4 inch eps are not yet released in the US. Supposed to be two entirely different animals.
We'll see...
The comment from the rep as we stood there and discussed the 125 was
we will soon be making this model available to take interchangable 1.25" eyepieces.
edz
Hummmm......I'll call Mike at Vixen to get the real scoop.
State tune for further details....
-------------------- 10x50 Fujinon FMT-SX binos
15x70 AP binos + Paragon p-mount
Oberwerk 100BT 45 degree + Hercules fork mount
120mm f/5 Orion achromat + Moonlite focuser
140mm f/5.7 Vixen NeoAchro Petzvel refractor
150mm f/6.5 Antares achromat
150mm f/8 homemade achromat....EE Barnard MW Sweeper
8 inch newt with f/5 Swayze mirror
10 inch f/4.7 Orion newt + Paracorr
15 inch f/5 Discovery split tube
35mm Pan, 26mm Nagler, 17mm Nagler, 13mm Ethos, 8mm Ethos
Member IDA
|
EdZ
Professor EdZ
   
Reged: 02/15/02
Posts: 12562
Loc: Cumberland, R I , USA42N71.4W
|
|
Well, that should clear up anything. It was Mike I spoke with at NEAF.
edz
-------------------- Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
|
Rick
Carpal Tunnel
   
Reged: 04/12/05
Posts: 2573
Loc: Tokyo, Japan
|
|
FWIW, there are no Vixen 125mm binoculars available in Japan either fixed mag or with interchangeable eyepieces and none seem to be in the works. Occasionally, their online outlet will have a pair of refurbed 30x125mm, but it is not a normally stocked item.
clear skies, Rick
-------------------- www.japanastro.com
|
edwincjones
Post Laureate
   
Reged: 04/10/04
Posts: 4415
|
|
How do the Vixens compare to the BT120s as far as quality, FOV, weight, etc to justify the increase in cost?
edj
--------------------
n w arkansas
Binocular, Solar, General Amateur Astronomy
|
edwincjones
Post Laureate
   
Reged: 04/10/04
Posts: 4415
|
|
Once, at a star party I had a chance to compare the old Orion/Vixen 125s with zoom eps with my big fugis.
They had good optics and build, but a very small FOV (that the interchangeable eps could correct).
I have never seen a BT100, but my guess is they are close in quality.
edj
--------------------
n w arkansas
Binocular, Solar, General Amateur Astronomy
Edited by edwincjones (06/25/08 06:35 PM)
|
milt
sage
   
Reged: 09/13/04
Posts: 429
Loc: Arizona
|
|
Quote:
FWIW, there are no Vixen 125mm binoculars available in Japan either fixed mag or with interchangeable eyepieces and none seem to be in the works. Occasionally, their online outlet will have a pair of refurbed 30x125mm, but it is not a normally stocked item.
I heavily researched what we will call the "old" Vixen 125mm before deciding to get my binoscope. At various times it was available in three versions: 1) Fixed mag 20x or 30x, 2) Zoom mag and 3) Interchangeable ep's. Allister St Claire owned one and his experiences helped dissuade me from taking the plunge:
http://www.telescopereviews.com/documents/orion_binos_cna.pdf http://www.telescopereviews.com/documents/labts.pdf
The false color by itself is not an indictment of Vixen's optics because a 125mm f/5 achromatic doublet is going to be what it is going to be. However, the spiky stars and soft field edge that Allister found in two examples and undersized exit pupil Ed is seeing 4 yrs. later don't belong in a $4,000. instrument. IMHO....
Milt
|
GlennLeDrew
professor emeritus
Reged: 06/18/08
Posts: 608
Loc: Ottawa, Ontario, Canada
|
|
I checked out a pair of Vixens at a star party (Starfest, NW of Toronto) several years ago. They were the fixed power model, working at 30X if I recall. I wasn't impressed. As Edz noted, the exit pupil was undersized, because of a too-small prism aperture which stopped down the system. The collimation wasn't the best, and I didn't see at the time an easy way to tweak this.
The chromatic aberration was just what you'd expect for that size achromat. But the view just wasn't as sharp as it should have been. I attributed it to slight mis-alignments in the prism train, resulting in some astigmatism (no, it wasn't my own eyes--the orientation wasn't right.)
==============
Some years before, I had built a 5" f/5 right angle bino for a friend, using a pair of decent (~1/3 lambda wavefront error) objectives from American Optical. I used all mirrors (enhanced aluminum) for folding/redirecting the light path. Moreover, I added 2-axis (U/D and L/R) collimation adjustment for one side of the instrument, easily performed by simply turning one or both small knobs. My buddy uses premium eyepieces (mostly Naglers and Panoptics) from 40mm down to 4.8mm. This instrument blows away the Vixen, mainly because I made sure the optical axes entered the eyepieces centered and true. And it can nicely illuminate the huge fields of 2" eyepieces having field stops up to 48mm diameter. For deep sky "fuzzies" they're the shinizzle, and they're not so bad on double stars, either!
=============
I suspect the newer Vixen will simply be the older model, with new eyepiece barrels replacing the original fixed eyepiece barrel. If that's the case, I don't hold out much hope for an improvement, I'm afraid.
-------------------- Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
|
milt
sage
   
Reged: 09/13/04
Posts: 429
Loc: Arizona
|
|
Quote:
the view just wasn't as sharp as it should have been. I attributed it to slight mis-alignments in the prism train, resulting in some astigmatism
Glenn, I think you're exactly right. What Allister describes sounds like the "sweet spot" was definitely somewhere other than field center. As you point out, even 1/3 wave optics can be respectable providing the alignment is correct.
Milt
|
Tamiji Homma
sage
Reged: 02/24/07
Posts: 413
Loc: California, USA
|
|
Quote:
Hummmm......I'll call Mike at Vixen to get the real scoop.
State tune for further details....
I am interested in new Vixen, too. I like my 20x125 as sweeper but I'd love to look through with well corrected wide eyepieces.
By the way, here is exit pupil of 20x125, It is about 6mm, maybe slightly larger.
Tammy
|
Mr. Bill
Carpal Tunnel
  
Reged: 02/09/05
Posts: 2757
Loc: Just passing through.....
|
|
Talked to Mike Fowler this morning....he confirms that the new model is the same design as the 30x and 20x fixed powers set up for interchangeble eps. I also told him about edz's discussion at NEAF; he didn't remember it. Sent him link to this thread and he told me he would contact Japan about undersized exit pupil issue and get back to me. Will pass it along as soon as I know anything.
I got bad info (or misunderstood the meaning of "new design") from Mike Bieler at Astronomics about this being a completely new design.
-------------------- 10x50 Fujinon FMT-SX binos
15x70 AP binos + Paragon p-mount
Oberwerk 100BT 45 degree + Hercules fork mount
120mm f/5 Orion achromat + Moonlite focuser
140mm f/5.7 Vixen NeoAchro Petzvel refractor
150mm f/6.5 Antares achromat
150mm f/8 homemade achromat....EE Barnard MW Sweeper
8 inch newt with f/5 Swayze mirror
10 inch f/4.7 Orion newt + Paracorr
15 inch f/5 Discovery split tube
35mm Pan, 26mm Nagler, 17mm Nagler, 13mm Ethos, 8mm Ethos
Member IDA
Edited by Mr. Bill (06/26/08 02:05 PM)
|
davidmcgo
sage
Reged: 10/09/04
Posts: 446
Loc: San Diego, CA
|
|
Hi Tammy,
If you move the ruler to where the projected light is sharp edged, that would show the exact exit pupil diameter I think. There can be a difference between how it appears on the eyepiece exit as you've photographed and at optimal position where you'd get a focused disk on the frosted ruler.
Dave
|
Tamiji Homma
sage
Reged: 02/24/07
Posts: 413
Loc: California, USA
|
|
Hi, Dave.
I took the photo after I focused to infinity and taped the ruler on edge of the eyepiece. So the ruler is a few millimeters away from eye lens.
Then I manually focused the exit pupil with f/22 to get decent DOF so that ruler can be in focus to read along with the exit pupil.
I've been wondering I should get the ruler back away from the eye lens to project, where my eyes were when I set focus to infinity? If so, it is little bit tricky to place the ruler at the right distance from eye lens.
Tammy
|
WRose
Pooh-Bah
   
Reged: 07/08/05
Posts: 1043
Loc: Colorado, USA
|
|
Mr_Bill, I use the 24mm Panoptics, 24mm Brandons, 7/8" Brandon (~22mm), 19mm Panoptics, and then Nagler T6s on down in my Bt-125HFT. I have also used many of the 'high End' planetary EPs with these. When you get into higher powers a pair of Baader Semi-APO filters do help knock down the fringing especially on the brighter planets. From what I've heard they are a new 'design' the same as the fixed versions recently displayed/sold. With high quality eyepieces, the objectives are the weakest link in the BT-125HFT. Don’t know about the new version but suspect it’s the same,
Milt, The BT-125 HFT don't have nearly as much fringing (CA) as the earlier versions. With Filters 200x is not a problem even for bright targets.
Quote:
However, the spiky stars and soft field edge that Allister found in two examples . . .
Not an issue with my BT-125HFT. With 24mm Panoptics & Brandons I don't get a 'soft edge'. The 25W Masuyama work very well with the BT-125HFT telebinocular. On nights of very good or beeter seeing and transparency the Zeiss A-4 and 4mm TMB-Supermonos bino nicely with the BT-125HFT although the 5mm seems to work a little better most of the time. The 3.5 Naglers and Pentax XWs are about as much as you can push them at ~220x and are surprising on nights when conditions are great. Understand these are not an APO and don't compare to the NP-127 for color correction, etc. as expected. They are not 150mm Fujinons either. But at $4,800.00 for the complete kit with foot locker size shipping case, I haven't regretted buying them.
-------------------- Clear Skies, Bill
|
Mr. Bill
Carpal Tunnel
  
Reged: 02/09/05
Posts: 2757
Loc: Just passing through.....
|
|
Hi Bill Rose...
I think that what is being offered is what you now have?? Talking to Mike Fowler at Vixen, he confirmed that there was a limited release of about 20-30 units in the US of the interchangable models. I think the upcoming binoculars are probably a re-release of what you have at $4000 instead of $4800.
Can you measure your exit pupils using say the 24 Pans and see if you are getting the full aperture? This would answer the question and is the one thing that will make me decide on "pulling the trigger" on the upcoming release. Also, what is your opinion of the coatings, baffling, and collimation.
Is there provision for collimation if necessary. I've read reviews where that was apparently a problem.
Since I would use these at only low or moderate power, high power deficiencies are not important to me.
-------------------- 10x50 Fujinon FMT-SX binos
15x70 AP binos + Paragon p-mount
Oberwerk 100BT 45 degree + Hercules fork mount
120mm f/5 Orion achromat + Moonlite focuser
140mm f/5.7 Vixen NeoAchro Petzvel refractor
150mm f/6.5 Antares achromat
150mm f/8 homemade achromat....EE Barnard MW Sweeper
8 inch newt with f/5 Swayze mirror
10 inch f/4.7 Orion newt + Paracorr
15 inch f/5 Discovery split tube
35mm Pan, 26mm Nagler, 17mm Nagler, 13mm Ethos, 8mm Ethos
Member IDA
|
Wes James
Carpal Tunnel
   
Reged: 04/12/06
Posts: 2454
|
|
Re. Collimation adjustability, I don't know about the 125's, but I have the Vixen BT-80M's, and if you peel back the black covering right under/beside the eyepiece, there are screws to tweak the prism's.
-------------------- Wes
Atlantic Beach, FL
Some bino’s from Miyauchi 5x32 Binon's up through Garrett 20x110 Signature's,
Some telescopes from a Stellarvue 80mm NHNG up through a couple of 8” reflectors…
And a wonderful 4.25" Delmarva Shiefspiegler!
Some good friends, made here on C/N.
Oh- several cats and a wonderful wife!
Anyone want a cat???? :-O
"When your work speaks for itself- Don't Interrupt" -Gamble Rogers
|
WRose
Pooh-Bah
   
Reged: 07/08/05
Posts: 1043
Loc: Colorado, USA
|
|
Quote:
Can you measure your exit pupils using say the 24 Pans and see if you are getting the full aperture?
This was checked and rechecked by several people when I first got these. The answer is Yes, they are Full Aperture. There is no restriction of vignetting.
Quote:
Is there provision for collimation if necessary. I've read reviews where that was apparently a problem.
There are provisions to allign the tubes and the prisms. I've never had any particular problem with them being out of alignment. Even after long Pacific transits they've been just fine. I'm sue they could get out of alignment but it's not common on mine. I tweak them ocassionally like maybe once every 18 months.
For $4,000.00 I'd chack and make sure that includes the mount, HAL110 tripod, and heavy duty shipping case along with the 6x30 Finder Scope, etc. Also check if they have the ability for encoders and computer. Not saying it isn't as I don't know, I'd just be surprised if they're selling the same thing for $800.00 USD less after 5 years. Supposedly they stopped making them because they couldn't afford to make them at that price and people wouldn't buy them for more.
-------------------- Clear Skies, Bill
|
Anders Asp
newbie
Reged: 07/18/08
Posts: 1
Loc: Eskilstuna, Sweden
|
|
Hi there all of u! Have anyone heard or seen any new information about the new vixen 125mm binos? I will try to get a pair shipped to Sweden where i live, i just hope the binos will be as good as vixen says... Its kind of nice to be able to pick any magnification you want, i kind of like that. I hope the colorcorrection will be good and the sharpness will be good also. I wonder what the maximum field of view is and with what ep:s to get that.
Right now i have Widescan Type III 20mm x2 and 13mm x2, the ep:s are 84deg. I hope they will work good in the new vixen binocular.
/ Anders Asp
|
Vincent33
member
Reged: 09/18/07
Posts: 95
|
|
Quote:
Have anyone heard or seen any new information about the new vixen 125mm binos?
Now they have a place in the Vixen pages:
http://www.vixenoptics.com/binoculars/bt125.html
they are the models with interchangeable eyepieces.
The f ratio is 6.08, didn't seen it mentioned before in this thread.
But the BAD news is that these huge guys JUST "collect 300% more light than the naked eye" ... RUBBISH! ;-)
|
Gordon Rayner
professor emeritus
Reged: 03/24/07
Posts: 506
|
|
RE: Interchangeable eyepieces
I had nothing but disappointment from putting wide field Tele-Vue oculars on WW II f/3.5 Busch 10 x 80, and similar, but better bad results on WW II Toko and Toyokawa Navy Arsenal (Kowa)15 x 105 , which are f/4 or f/4.5 , as I recall, in particular combined with the Fuji eyepiece for their 25 x 150 straight view.
The late Kevin Kuhne did a lot of eyepiece substitution on WW II military binoculars. There had to be an element of chance /and or compromise, though I did not view through any of his modified equipment.
In many/most/ cases, the designer balances the eyepiece errors to those of the prisms and the objectives. See Hopkins in Mil . Handbook 141, for example.
Things will be better at f/5 or longer, of course. There is an element of chance/compromise in arbitrary use of eyepieces not specifically designed for a particular combination of objective and prism. The eyepieces mentioned in this thread have not been designed for use with a particular prism glass path and index. The errors may be acceptable(?) but they must be there.
|
edwincjones
Post Laureate
   
Reged: 04/10/04
Posts: 4415
|
|
Quote:
How do the Vixens compare to the BT120s as far as quality, FOV, weight, etc to justify the increase in cost?
edj
--------------------
n w arkansas
Binocular, Solar, General Amateur Astronomy
|