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cuzimthedad
Just Be Cuz
Reged: 04/09/06
Posts: 3725
Loc: Sonoma, Northern California
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Used both and replaced 6x30 with the 9x50. I use the 9x50 with both my 20" dob and 6" achro.
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Dan
20" f/5 Obsession
Antares 1529
TV102
Various Naglers, Ethos, UO Orthos and TV Plossls
The Off Fisher Lane Irregulars
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gnowellsct
professor emeritus
Reged: 06/24/09
Posts: 733
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If we're talking about the Celestron/Orion 9x50 I would recommend against getting it. I really think this is a poorly made instrument and I don't like the tiny little barrel thingy.
If you can get a "Made in Taiwan" Meade 8x50, these are pretty good!
The Vixen finders are excellent.
The Tak finder is fun to own, very pricey.
I've never seen a W.O. finder under the stars but I saw one once at NEAF and it look like a nice design.
An illuminated reticle finder is really nice to have and addicting. That said, the Meade 8x50 is nice because it has heavy black lines that you can see even without an illuminator.
So for an entry level scope I recommend the Meade made-in-Taiwan 8x50. It blows away the Celestron 9x50 in quality.
I don't like Meade, I don't buy Meade, but they got the 8x50 finder right. It's just plain a much better finder than the Celestron/Orion 9x50.
I have to add that I have no use for 6x30s. A good 8x50 or 7x50, and a well-made 9x50, are nice to have. Stellarvue makes a nice finder but they are right angle.
regards
Greg N
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"Aperture will get you through times of no money better than money will get you through times of no aperture."
featuring selected astrojunk:
bunch o' widefield eyepieces
bunch o' narrowfield eyepieces
couple o' Barlows
couple o' scopes
couple o' mounts
couple o' tripods
and a pier 'n' stuff
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StarStuff1
scholastic sledgehammer
Reged: 04/01/07
Posts: 989
Loc: South of the Mason-Dixon Line
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The old "rule" was that the finder should have 1/4th the aperture of the main instrument. So, a 1.5-in finder, or a 38.1mm finder should work just great.
Go for a 50mm finder.
Or, don't even get a separate finder and get a 55mm plossl and have a built in 14x finder.
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Tools that make objects very far away appear much closer than they actually are.
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Doug76
Postmaster
Reged: 12/05/07
Posts: 5564
Loc: SE Louisiana, future Texan
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I use 6x30's on my 60mm refractors. 8-9x50's on everything else.
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Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors, 50mm-150mm
1 apo refractor, 90mm
1 SCT, 8 inch
UO Abbe Volcano Tops
Faworski Ortho's
Panoptic 24mm
Carton 100mm f/13 under construction 
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NCMountains
scholastic sledgehammer
Reged: 01/02/09
Posts: 1131
Loc: NC- USA
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I just picked up a 7x50 Antares rt. angle finder for the CPC. Got good reviews and has a replaceable EP to boot.
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CPC800 XLT SCT
Baader Hyperion EP's (8mm, 17mm, 24mm)& FTR's 14mm & 28mm; 40mm Celestron Plossl (came with scope) Vixen 30mm Plossl
GSO Barlow 2x; GSO 2" diagonal
UHC Nebula 1.25" filter
Orion solar filter
Orion StarShoot II CCD
Celestron Neximager (for solar system imaging)
Hirsch f6.3 focal reducer
Celestron SkyScout IYA2009
Mt. Pisgah Sky Chart:
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Luigi
Post Laureate
Reged: 07/03/07
Posts: 4947
Loc: MA
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>>>The old "rule" was that the finder should have 1/4th the aperture of the main instrument. <<<
What were the assumptions and rationale behind that rule?
The only reason to put a finder on a scope is to provide a sufficiently greater FOV to enable locating objects. It's the TFOV that matters, the aperture is almost irrelevant.
If a 60 mm scope will serve well as a finder on a 12" scope, why would a 60mm scope need a finder at all? If it's f/12 with .965 EPs, the max possible TFOV will be about 1.75 degrees making it difficult to locate objects, so a finder that provides a 5 deg or wider FOV would be very helpful, whether it's 30mm or even a larger aperture than the main OTA.
My 120ED will provide almost a 3 degree TFOV so I can reasonably get by without a finder. If I were to put one on it, the only reasons would be to provide a wider TFOV.
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17.5" f/5 Dob. IM-715 MCT. 120ED. Lunt 60mm Ha.
Zeiss, Leica, Fujinon, Nikon, Pentax, Bushnell bins
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sailor70623
scholastic sledgehammer
Reged: 01/12/08
Posts: 944
Loc: Ok.
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Luigi has it right again. It's TFOV in a finder that is important. But I also find that it should go deep enough to be used star hopping too. 50mm on all my scopes, and I always get the 8X over the 9X to both open up the TFOV and let more light in for the cross hairs. I mostly use the cheap GSO RACI finders. I find the RACI easier to use to get the scope on target. Easier on my neck too. Many nights I end up using only the telrad. A telrad will work better than most cheap finder scopes. They are very fast and easy to use, cheaper too.
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Corornado PST
LB 16" & 12"
Z 10"
LX50 8"
8" CPC
ETX127
102&90mm MAKs
80mm Richfield APO
70mm refractor
ETX60
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peter k
super member
Reged: 02/03/07
Posts: 172
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I've had both, but now only have the 6x30, which I use on my 10" dob. I observe pretty much exclusively at dark sites, where the 6x30 goes to mag 9. This is deeper than, for instance, Sky Atlas 2000, and as deep as Uranometria. I have no need to go deeper than that for starhopping, and I like the compactness and lightness of the 6x30.
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KWB
Postmaster
Reged: 09/30/06
Posts: 9269
Loc: Westminster,Co Elev.1646Meters
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A 6 X 30 finder has it's place. In this example the added weight of the GSO 50mm finderscope overwhelmed the capability of this EQ1 mount. With the smaller finder the setup is useable and IMO more like it when using a real small OTA. The SV F50 finder is even heavier.
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Kenny
"Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe." - Albert Einstein
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CounterWeight
Pooh-Bah
Reged: 10/05/08
Posts: 1303
Loc: PDX chronoplast
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for - goto, star hopping, both?... imaging? Mount?
I have 2 I use, a Tak 7*50 and a Baader 8*50, both illuminated. Honestly with all the parallax error in the plastic battery quasi HUD type box's I am back to these forever I think.
I can look down the optic tube of my telescope to get it close enough to use them on something - enough to get me going... but I think there is a balance to the scope/ep FOV that you do your hunting with and the finder that will make you happy with that scope... 6" f5 must be a wide field, maybe the 6*30 is a better compliment? In a way I'm really used to them (7/8*50)no matter the scope used... is this to be a 'tween' the Rigel and main scope?
After buying my TEC and using the mount for the finder they make - I'd add that the finder mount can make using it easy or hard... TEC amazing easy (very quick to align and use) and accurate, Tak can be difficult and time consuming (but a terrific optic) and accurate after setup...
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 - 
CGE (Frankenmount mod.)
Onyx 80ED, Tak FS-128 #02058, TEC APO160ED #030
CCD: Orion SSPDSCIv2, SSI3, SSAG
diags, ep's, tubes, filters, Binocs
My CN Image Gallery
Experience is a difficult teacher, it gives the test first, and gives the lesson later
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TimD
scholastic sledgehammer
Reged: 02/16/05
Posts: 907
Loc: CA USA
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I have upgraded two scopes that I had previously put 6x30's on with 8x50 finders. I gave the 6x30's a good try, but they just didnt compare to the light grasp and fov of the 50mm. the 50 looks a bit large on my 3 in refractor, but as I said the 6x30 didn't cut it (for me at least)
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Takahashi TSC 225
WO Megrez 102
Meade ETX 90, ETX 125
Meade LX90
Classic Orange tube C14, C90, C5+
Etc,Etc,Etc!!
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arpruss
scholastic sledgehammer
Reged: 05/23/08
Posts: 858
Loc: Waco, TX
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A consideration is that a large finder is also a nice thing for looking at objects that are too wide for the main scope (without having to pull out binos). I ended up making a straight-through 13x68 (from one of MASILMW's $12 lenses, an old Kellner and some cardboard tubes). 20 oz for the finder, and currently another 16 oz for a quick-and-dirty wooden alt-az mount to attach it to the main scope (I hope to reduce that significantly). It would, however, look a bit funny on a 6", so I'd go for a 50 or 60.
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Coulter Odyssey 13.1" split-tube
Coulter Odyssey 8"
Home-made 7.8" F/4 dobsonian travel scope
Home-made 68mm F/5.3 achro (typically used as finder on 13.1")
Skymaster 15x70
BPTs4 8x30
32mm Plossl, 30mm Rini, 27mm Kellner, 13mm Hyperion, 6mm TMB/BO Planetary, Owl 2X Barlow
Palm TX with AstroInfo and RescoViewer
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