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Mr. Bill
Carpal Tunnel
Reged: 02/09/05
Posts: 2748
Loc: Just passing through.....
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I have really become enthusiastic about using a small telescope side by side with my 100mm BTs.
The BTs with 24 Pans give me 25x with a 2.7 degree fov and my 140mm (5.5 inch) Vixen Petzvel refractor with the 13 Ethos at 62x and a 1.6 degree fov complements it perfectly for "zooming in" on targets of interest swept up in the binocular field.
Both the binoculars and the refractor give wide angle high contrast views perfect for sweeping the summer/fall MW.I have found the Cygnus/Cepheus/Cassiopeia MW particularly productive in providing great views of light/dark nebulae and open clusters embedded in the galactic arm starfields.
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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
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F.Meiresonne
Carpal Tunnel
Reged: 12/22/03
Posts: 2900
Loc: Eeklo,Belgium
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Strange you mentioned that.
Lately i have started to use a Helios 8X40 together with my 8 and 18 incher. As my reflectors have laserfinders it's quite easy to search for an object and then quide the scopes directly to the objects. Thats quite straightforward for finding real quick many targets.At the same time it shows me what is possible in 8X40 binoculars and they are also great for viewing large parts of the sky, particulary the Cygnus and Cassiopeia are the places to be...
In the past i never used small bino's much but it seems i underestimated a bit the possibilities. this could be because i really never owned good smaller bino's until now.
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Freddy Meiresonne
Obsession 18 inch #1638
Orion Optics 8 inch F/4.5 -1/8 wave optics -Vixen GP-E
20x80 Helios Stellar Binos
10x60 Helios Quantum 4(= Obie Mariner)
10x50 Helios Nature sport plus
8x40 Helios Nature sport plus
Eyepieces in use :Pan 35,24,19, N13T6, Pentax 10 XW, N9T6, Ultrascopic 7.5, TV2, baader ortho 12.5 and 9 mm
Edited by F.Meiresonne (08/13/08 05:12 PM)
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edwincjones
Post Laureate
Reged: 04/10/04
Posts: 4360
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Most of my observing is from my observatory in my yard in mag 4-4.5 skies, so I just pick either a scope or binoculars. I find that I am using smaller glass over time and more handheld than tripod binocs. It just depends on the ocassion and the object to be viewed.
edj
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n w arkansas
Binocular, Solar, General Amateur Astronomy
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Mr. Bill
Carpal Tunnel
Reged: 02/09/05
Posts: 2748
Loc: Just passing through.....
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I use Telrads on all my binoculars/telescopes so it is quite easy to duplicate positions between.
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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
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RichD
super member
Reged: 11/08/07
Posts: 197
Loc: Derbyshire, UK
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Hi Mr Bill
When i get my 'scope out (12" Dob) i like to have my 10x50s for finding and widefield MW views and a pair of 16x70s on a tripod for objects too large for the scope but needing a little more than 10x.
I have to say though that these days, prob 80-90% of my observing is binos only and most of that with the 16x70 and 10x50.
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Clear skies
Rich
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OpalescentNebula
member
Reged: 01/11/07
Posts: 52
Loc: Calgary, Alberta
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Dont have a telescope at the present.
Right now I use my 10x42s & 20x110s.
Im looking at getting an APO refractor from 90 110mm. I havent decided on what to buy. Keep on reading the refractor forum, and just get more confused.
I have on order an AP 130 & an AP 155 (to be delivered in the next decade) but I would like to have a refractor up and running in the next year.
My other thought would be to get another set of binoculars with 45 deg & changing magnification.
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Yours truly,
Bill
"Good friends are like stars...you don't always see them, but you know that they are always there" - unknown
Binos : Zeiss 10x42 FL, Garrett Optical 20x110
telescope: WO Megrez 110 ED
Eyepieces: 13mm Ethos, 5mm Pentax, 28mm WO
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Mr. Bill
Carpal Tunnel
Reged: 02/09/05
Posts: 2748
Loc: Just passing through.....
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Quote:
Hi Mr Bill
When i get my 'scope out (12" Dob) i like to have my 10x50s for finding and widefield MW views and a pair of 16x70s on a tripod for objects too large for the scope but needing a little more than 10x.
I have to say though that these days, prob 80-90% of my observing is binos only and most of that with the 16x70 and 10x50.
That's why I prefer a short focal length refractor as the next step up from binoculars in terms of fov and magnification.
It seems that a refractor and binos complement each other very well.
Also, both lend themselves to alt azimuth mounting and Telrad finders, which makes for simplicity and intuitive observing.
KISS...my philosophy these days.
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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
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Luigi
Carpal Tunnel
Reged: 07/03/07
Posts: 1960
Loc: Massachusetts
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I always wear bins on a harness when observing with any of my scopes. These have been 7x42 Leica, 8x32 Zeiss, and most recently 10x50 Nikon AE. I use the bins to get the lay of the land, then a Telrad and 9x50 finder to zero in.
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17.5" f/5 Discovery Truss
IM715 7" f/15 MCT, Eon-120ED
Lunt 60mm single etalon HA
CG5A coffee grinder, Orion Skyview Alt-AZ
35,19,15 Pans.9 Nag. Meade 24.5 4kSWA, 4.7 5kUWA.
BO-TMB 7mm planetary.
Zeiss Diascope 85
Zeiss, Leica, Canon IS, Fujinon, Nikon binos
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Luigi
Carpal Tunnel
Reged: 07/03/07
Posts: 1960
Loc: Massachusetts
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I always wear bins on a harness when observing with any of my scopes. These have been 7x42 Leica, 8x32 Zeiss, and most recently 10x50 Nikon AE. I use the bins to get the lay of the land, then a Telrad and 9x50 finder to zero in.
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17.5" f/5 Discovery Truss
IM715 7" f/15 MCT, Eon-120ED
Lunt 60mm single etalon HA
CG5A coffee grinder, Orion Skyview Alt-AZ
35,19,15 Pans.9 Nag. Meade 24.5 4kSWA, 4.7 5kUWA.
BO-TMB 7mm planetary.
Zeiss Diascope 85
Zeiss, Leica, Canon IS, Fujinon, Nikon binos
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F.Meiresonne
Carpal Tunnel
Reged: 12/22/03
Posts: 2900
Loc: Eeklo,Belgium
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I don't use often a Telrad. I think a Telrad works better in truly dark skies.I have it only as a backup whenever my laser does not work. I never took binoculars to our observing site, but from now on this will be different.
By using both my telescope and bino i discovered that i actually can see M71 in the bino wich i found quite stunning.
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Freddy Meiresonne
Obsession 18 inch #1638
Orion Optics 8 inch F/4.5 -1/8 wave optics -Vixen GP-E
20x80 Helios Stellar Binos
10x60 Helios Quantum 4(= Obie Mariner)
10x50 Helios Nature sport plus
8x40 Helios Nature sport plus
Eyepieces in use :Pan 35,24,19, N13T6, Pentax 10 XW, N9T6, Ultrascopic 7.5, TV2, baader ortho 12.5 and 9 mm
Edited by F.Meiresonne (08/13/08 05:11 PM)
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deSitter
scholastic sledgehammer
Reged: 12/09/04
Posts: 755
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Same here, although I did pick up a pair of Konus 20x80s from a friend who couldn't keep them collimated. We'll see how they work out. I have them pretty fairly collimated. I used the trick of rapping on the prism housing to reset the collimation spring and got sufficient travel to collimate them.
-drl
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Tony Flanders
Carpal Tunnel
Reged: 05/18/06
Posts: 2062
Loc: Cambridge, MA, USA
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Quote:
That's why I prefer a short focal length refractor as the next step up from binoculars in terms of fov and magnification.
Well yes, but ...
Why not just use shorter focal-length eyepieces on your BT-100 to achieve the same effect? My experiments hint that at identical magnification, binoculars are pretty nearly equivalent in how much you can see (though of course not in subjective experience) to a telescope of identical light-gathering ability. In other words, when used at not-very-wide exit pupils, 100-mm binoculars are more or less equivalent to a 140-mm telescope running at the same magnification.
True, the 13-mm Ethos is physically too big to use in a binocular telescope, so you'd have to settle for the 82-degree AFOV of the Nagler rather than the 100-degree AFOV of the Ethos. But is that such a greivous loss?
Quote:
It seems that a refractor and binos complement each other very well.
Odd! I would say that they complement each other particularly poorly. Put another way, of all conventional telescopes, short-focus refractors are the instruments that most nearly overlap the capabilities of binoculars. Not surprising, considering that binoculars are simply pairs of short-focus refractors.
I would say that quite clearly, SCTs are the instruments that best complement binoculars. The one thing that SCTs can't deliver is wide FOV -- but the binoculars take care of that.
Like you, I prefer altazimuth mountings, and I like at least a little overlap between the capabilities of the binoculars and telescope. From that point of view, I'd say that the ideal complement for 100-mm binoculars is an 8-inch or 10-inch Dob.
Either the SCT or the Dob would provide the two things that the binoculars really can't give you: serious aperture and decent views at medium to high power.
I don't have the mental discipline to use a big, high-quality scope and restrict myself to low magnifications as you do. A 1.6-degree TFOV is far too big and low-power to provide decent views of the overwhelming majority of open clusters. As for nebulae, both bright and dark, they're all over the place. Some are too big even for binoculars, and some really crave high magnification.
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Tony Flanders
eyeglasses
6x15 and 8x32 monoculars
8x25, 7x35, 10x30 IS, 10x50, and 15x70 binoculars
70mm and 100mm achromatic refractors
4.5", 7", and 12.5" Dobs
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Joe Ogiba
Post Laureate
Reged: 02/14/02
Posts: 3340
Loc: NJ USA
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Quote:
True, the 13-mm Ethos is physically too big to use in a binocular telescope, so you'd have to settle for the 82-degree AFOV of the Nagler rather than the 100-degree AFOV of the Ethos.
84° vs 100° in a BT
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Pentax PF-80ED
Meade 102ED APO
Orion EON 72
120ST
Apex 127
C6 XLT
CR150
C9.25
XT10
Zeiss 7x42 FL
Canon 10x42L IS WP
15x50 IS
12x36 IS II
Garrett Optical 28x110 HD-WP Signature Series
Oberwerk BT-80 45
Apogee RA-88-SA
Denk II Power x Switch binoviewer w/13mm Ethos, 20mm Pentax XW's, 20mm Widescan III's.
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Mr. Bill
Carpal Tunnel
Reged: 02/09/05
Posts: 2748
Loc: Just passing through.....
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Well...
That's why I posted this thread..different strokes, etc.
Truth be known, I normally observe with the BT100s, 140 Vixen and 10 inch set up side by side by side. All on alti azimuth mounts with Telrads.
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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
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Fiske
Carpal Tunnel
Reged: 03/14/04
Posts: 2057
Loc: Missouri / United States
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Quote:
Most of my observing is from my observatory in my yard in mag 4-4.5 skies, so I just pick either a scope or binoculars. I find that I am using smaller glass over time and more handheld than tripod binocs. It just depends on the ocassion and the object to be viewed.
edj
edj:
Sounds like we have virtually identical observing environments.  I'm in KC.
I split my observing time between a TV-101, an 8-inch Dob (XT-8), and a home built 22-inch Dob on the telescope side. For binos I use either a Nikon 8x42 LX or Nikon 12x50 SE. I tend to use the 8x42 more for a finding aid at the scope, and the 12x50 more when I am concentrating on bino observation, though it is generally better on a tripod because of the magnification. I'm missing a good 10x pair at the moment, but will probably add a premo binocular (10x42 LX or EDG) sometime this year or early next.
I have found the 8x42s are remarkably nice used in conjunction with the TV-101 at a dark sky site. They seem to complement each other well.
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Fiske Miles
Nikon 8x42 LX / 12x50 SE Binos
Mini Borg 60ED, TV-101, AT80Ach, XT-8, C11/CI-700, 22-Inch Dob
Way too many Nagler eyepieces
http://www.fiskemiles.blogspot.com/
www.fiskemiles.com
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milt
sage
Reged: 09/13/04
Posts: 424
Loc: Arizona
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Quote:
I don't have the mental discipline to use a big, high-quality scope and restrict myself to low magnifications as you do. A 1.6-degree TFOV is far too big and low-power to provide decent views of the overwhelming majority of open clusters.
Tony, I don't think Bill is necessarily restricting himself to low magnifications in the scope just because it has a short focal length - he could still use higher mag's as necessary for the object he is comparing with the binocular. I do agree that a 1.6° field doesn't push the optics.
It used to amaze me that my TV101 Petzval could show me everything from 4° fields at low powers to near-perfect diffraction patterns at high. A well-executed Petzval (difficult due to the alignment of the two groups) is a joy to behold.
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Clear skies, Milt
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Joe Ogiba
Post Laureate
Reged: 02/14/02
Posts: 3340
Loc: NJ USA
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The other night I had my BT80-45's on Bogen 501/475 combo, 28x110's on 12" Hercules fork mount, C9.25 with Denk II and a pair of 13mm Ethos on Giro 2DX mount and XT10 10" dob.
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Pentax PF-80ED
Meade 102ED APO
Orion EON 72
120ST
Apex 127
C6 XLT
CR150
C9.25
XT10
Zeiss 7x42 FL
Canon 10x42L IS WP
15x50 IS
12x36 IS II
Garrett Optical 28x110 HD-WP Signature Series
Oberwerk BT-80 45
Apogee RA-88-SA
Denk II Power x Switch binoviewer w/13mm Ethos, 20mm Pentax XW's, 20mm Widescan III's.
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BobinKy
scholastic sledgehammer
Reged: 04/27/07
Posts: 930
Loc: Country road
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During my recent decision to add telescopes to my binocular collection I looked at four specifications: magnification, limiting magnitude, FOV, and exit pupil. My goal was to identify two or three telescopes that would provide a natural progression from the binoculars I use for night sky observing.
Another goal was to keep my optics as simple as possible. Therefore, I researched refractors and Dobsonian reflectors, avoiding compound telescopes like the popular SCT. I am not interested in doing astrophotography.
Since what the observer carries in the eyepiece case is critical to what can be see with a telescope, I included a manufacturer's line of eyepieces for each scope listed below: Pentax XW--a new (but expensive) line that is receiving good reviews in the threads. I added the Televue 2.0 Powermate (a barlow of sorts) as the last spec for the 15-inch reflector. The 5mm eyepiece with the Powermate 2.0 probably represents the limit of the 15-inch scope.
The progression tables include the binoculars that I use for night sky observing and three scopes I am considering purchasing in the future: 90 mm APO refractor, 10 inch reflector, and 15 inch reflector. The (a) magnification spec measures power, (b) limiting magnitude provides a limit on the magnitude of objects that can be viewed with the optics, (c) FOV tells how much of the night sky will appear in the eyepiece, and (d) exit pupil is a rough handle on how bright the object will appear.
Finally, I have attached the Excel spreadsheet that I used to calculate the specs for those who want to plug in other models of binoculars, telescopes, and eyepieces.
My first scope purchase will go deep with a 15-inch reflector. I am still undecided on which eyepieces to start with. Any suggestions?
(a) MagnificationBinoculars
Fujinon FMT-SX 7x50....7x
Pentax DCF 10x50....10x
Fujinon FMT-SX 16x70....16x
Garrett Signature 22x85....22x
Stellarvue SV90T f/7.0 90 mm APO Refractor
Pentax XW 40mm eyepiece....16x
Pentax XW 30mm eyepiece....21x
Pentax XW 20mm eyepiece....32x
Pentax XW 14mm eyepiece....45x
Pentax XW 10mm eyepiece....63x
Pentax XW 7mm eyepiece....90x
Pentax XW 5mm eyepiece....126x
Pentax XW 3.5mm eyepiece....180x
Orion XT10 f/4.7 10-inch reflector
Pentax XW 40mm eyepiece....30x
Pentax XW 30mm eyepiece....40x
Pentax XW 20mm eyepiece....60x
Pentax XW 14mm eyepiece....86x
Pentax XW 10mm eyepiece....120x
Pentax XW 7mm eyepiece....171x
Pentax XW 5mm eyepiece....240x
Pentax XW 3.5mm eyepiece....343x
Discovery PDHQ f/5.0 15-inch reflector
Pentax XW 40mm eyepiece....48x
Pentax XW 30mm eyepiece....64x
Pentax XW 20mm eyepiece....95x
Pentax XW 14mm eyepiece....136x
Pentax XW 10mm eyepiece....191x
Pentax XW 7mm eyepiece....272x
Pentax XW 5mm eyepiece....381x
Pentax XW 3.5mm eyepiece....544x
Pentax XW 5mm eyepiece w/ 2.0 powermate....762x (b) Limiting Magnitude
Night Sky of NELM 5.6Binoculars
Fujinon FMT-SX 7x50....9.4
Pentax DCF 10x50....10.1
Fujinon FMT-SX 16x70....11.0
Garrett Signature 22x85....11.6
Stellarvue SV90T f/7.0 90 mm APO Refractor
Pentax XW 40mm eyepiece....11.2
Pentax XW 30mm eyepiece....11.6
Pentax XW 20mm eyepiece....12.1
Pentax XW 14mm eyepiece....12.5
Pentax XW 10mm eyepiece....12.8
Pentax XW 7mm eyepiece....13.1
Pentax XW 5mm eyepiece....13.3
Pentax XW 3.5mm eyepiece....13.4
Orion XT10 f/4.7 10-inch reflector
Pentax XW 40mm eyepiece....12.6
Pentax XW 30mm eyepiece....13.3
Pentax XW 20mm eyepiece....13.9
Pentax XW 14mm eyepiece....14.4
Pentax XW 10mm eyepiece....14.8
Pentax XW 7mm eyepiece....15.2
Pentax XW 5mm eyepiece....15.5
Pentax XW 3.5mm eyepiece....15.7
Discovery PDHQ f/5.0 15-inch reflector
Pentax XW 40mm eyepiece....13.6
Pentax XW 30mm eyepiece....14.2
Pentax XW 20mm eyepiece....14.8
Pentax XW 14mm eyepiece....15.3
Pentax XW 10mm eyepiece....15.7
Pentax XW 7mm eyepiece....16.1
Pentax XW 5mm eyepiece....36.4
Pentax XW 3.5mm eyepiece....16.5
Pentax XW 5mm eyepiece w/ 2.0 powermate....16.2 (c) FOV
1° = 60 (both measures reported)
FOV reported is manufacturer's advertised FOV Binoculars
Fujinon FMT-SX 7x50....7.5° 450
Pentax DCF 10x50....5.0° 300
Fujinon FMT-SX 16x70....4.0° 240
Garrett Signature 22x85....3.0° 180
Stellarvue SV90T f/7.0 90 mm APO Refractor
Pentax XW 40mm eyepiece....4.4° 267
Pentax XW 30mm eyepiece....3.3° 200
Pentax XW 20mm eyepiece....2.2° 133
Pentax XW 14mm eyepiece....1.6° 93
Pentax XW 10mm eyepiece....1.1° 67
Pentax XW 7mm eyepiece....0.8° 47
Pentax XW 5mm eyepiece....0.6° 33
Pentax XW 3.5mm eyepiece....0.4° 23
Orion XT10 f/4.7 10-inch reflector
Pentax XW 40mm eyepiece....2.3° 140
Pentax XW 30mm eyepiece....1.8° 105
Pentax XW 20mm eyepiece....1.2° 70
Pentax XW 14mm eyepiece....0.8° 49
Pentax XW 10mm eyepiece....0.6° 35
Pentax XW 7mm eyepiece....0.4° 25
Pentax XW 5mm eyepiece....0.3° 18
Pentax XW 3.5mm eyepiece....0.2° 12
Discovery PDHQ f/5.0 15-inch reflector
Pentax XW 40mm eyepiece....1.5° 88
Pentax XW 30mm eyepiece....1.1° 66
Pentax XW 20mm eyepiece....0.7° 44
Pentax XW 14mm eyepiece....0.5° 31
Pentax XW 10mm eyepiece....0.4° 22
Pentax XW 7mm eyepiece....0.3° 15
Pentax XW 5mm eyepiece....0.2° 11
Pentax XW 3.5mm eyepiece....0.1° 8
Pentax XW 5mm eyepiece w/ 2.0 powermate....0.1° 4 (d) Exit Pupil (mm) Binoculars
Fujinon FMT-SX 7x50....7.1
Pentax DCF 10x50....5.0
Fujinon FMT-SX 16x70....4.4
Garrett Signature 22x85....3.9
Stellarvue SV90T f/7.0 90 mm APO Refractor
Pentax XW 40mm eyepiece....5.7
Pentax XW 30mm eyepiece....4.3
Pentax XW 20mm eyepiece....2.9
Pentax XW 14mm eyepiece....2.0
Pentax XW 10mm eyepiece....1.4
Pentax XW 7mm eyepiece....1.0
Pentax XW 5mm eyepiece....0.7
Pentax XW 3.5mm eyepiece....0.5
Orion XT10 f/4.7 10-inch reflector
Pentax XW 40mm eyepiece....8.5
Pentax XW 30mm eyepiece....6.4
Pentax XW 20mm eyepiece....4.3
Pentax XW 14mm eyepiece....3.0
Pentax XW 10mm eyepiece....2.1
Pentax XW 7mm eyepiece....1.5
Pentax XW 5mm eyepiece....1.1
Pentax XW 3.5mm eyepiece....0.7
Discovery PDHQ f/5.0 15-inch reflector
Pentax XW 40mm eyepiece....8.0
Pentax XW 30mm eyepiece....6.0
Pentax XW 20mm eyepiece....4.0
Pentax XW 14mm eyepiece....2.8
Pentax XW 10mm eyepiece....2.0
Pentax XW 7mm eyepiece....1.4
Pentax XW 5mm eyepiece....1.0
Pentax XW 3.5mm eyepiece....0.7
Pentax XW 5mm eyepiece w/ 2.0 powermate....0.5
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Bob
38° Kentucky, USA
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12518
Loc: Cumberland, R I , USA42N71.4W
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Just a few comments.
Seems the LM predictions for a 90mm scope are very aggressive. There is a mag 13.1 star just outside the east side of M57. It takes about 100x in my 5" SCT to see that star. IIRC, it also takes about 100x in my TV102.
Why would you invest in an eyepiece combo that gives an 8.0-8.5mm exit pupil? It will reduce the effective aperture of your scopes by perhaps 20% - 30%. Yeh, I know, it gives a widest fov. BUT, it makes a 15" scope a 11-12" scope. It'll turn your 10" scope into a 7" scope.
If you want to know the real Tfov that you will see you need to look up the field stop diameter for these eyepieces. The Afov, especially in wide filed eyepieces is probably about 6%-8% larger than what you will see, due to distortion.
With a 2x Powermate in your case the 10mm and the 7mm eyepieces are redundant.
I'd recomend starting out with a set of TV plossls, and not spend $3500 for a set of eyepieces, Save $2500.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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BlueRidge
sage
Reged: 01/12/07
Posts: 288
Loc: Blue Ridge Mtns., VA
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I use the Miyauchi BR141s with 23x, 33x and 45x EPs (33x is the most oft used)
I have SV90BV and Denk II's with a Powerswitch and numerous EPs (14,20mm).
A killer combo for the most beautiful bright and dark nebula of the Milky Way constellations.
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Celestron Skymaster 15 x 70's, Miyauchi BR-141's
Celestron Nexstar 11 GPS, SkyAlign upgrade
Celestron 9.25 XLT OTA, CG-5 Mount
Stellarvue SV90TBV
Denk II Binoviewers/#S2 Power/Filterswitch
21mm and 14mm Denk EPs
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