whats the largest F4 to F6 focal ratio scope money can buy?

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realflow100 United States of America
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whats the largest F4 to F6 focal ratio scope money can buy?

#1

Post by realflow100 »


I dont like the really long focal length scopes because it makes it really hard to locate a target and center it. and the requirement of an obscenely long focal length eyepiece with humungus AFOV like a 2" 40mm 100*degree eyepiece with a focal reducer

I want to be able to take full advantage of largest exit pupil with 32mm to 20mm eyepiece as well as largest magnification that the telescope is capable of with 6mm eyepiece with or without a 2x barlow

What is a good wide view telescope around F4 to F6 focal ratio of size 8" to 12" that I could buy?
Svbony SV503 70mm ED F6 420mm FL refractor telescope (New)
Canon EOS 100D/SL1
Tamron 18-200mm F3.5-F6.3 II VC lens
canon 50mm STM F1.8
svbony 8-24mm zoom eyepiece
svbony goldline 66 degree 9mm and 6mm + 40mm plossl + 2x barlow.
svbony UHC 1.25 filter + astromania 1.25" O-3 filter + also an svbony H-B filter.
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Star Dad United States of America
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#2

Post by Star Dad »


I like my Orion 8" f4.9 fl1000mm Newtonian. Two fellows in my club have the Orion 8" f3.9 fl800mm astrograph. For me it was the compromise between planetary visual and DSOs. Hindsight being what it is - I probably should have gone with the astrograph as I have since inherited a number of refractor ~60mm fl1000mm and reflector 114mm fl1000mm scopes. Of course, I had no idea that I'd be this deep into AP.

I routinely use a 40mm and 30mm lens for visual in my Orion 8". Orion also makes a 10 inch version.
"To be good is not enough when you dream of being great"

Orion 203mm/f4.9/1000mm, converted TASCO 114mm/f9/1000mm to steam punk, Meade 114mm/f9/1000, Coronado PST, Orion EQ-G, Ioptron Mini-Tower and iEQ30, Canon 70D, ASI120MM,ASI294MC, Ioptron SkyHunter
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#3

Post by realflow100 »


can I have a few links to various options?
Svbony SV503 70mm ED F6 420mm FL refractor telescope (New)
Canon EOS 100D/SL1
Tamron 18-200mm F3.5-F6.3 II VC lens
canon 50mm STM F1.8
svbony 8-24mm zoom eyepiece
svbony goldline 66 degree 9mm and 6mm + 40mm plossl + 2x barlow.
svbony UHC 1.25 filter + astromania 1.25" O-3 filter + also an svbony H-B filter.
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#4

Post by Star Dad »


This is the site for Orion scopes: https://www.telescope.com/ . word of caution - you might end up spending a lot of time and money on that site.
"To be good is not enough when you dream of being great"

Orion 203mm/f4.9/1000mm, converted TASCO 114mm/f9/1000mm to steam punk, Meade 114mm/f9/1000, Coronado PST, Orion EQ-G, Ioptron Mini-Tower and iEQ30, Canon 70D, ASI120MM,ASI294MC, Ioptron SkyHunter
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#5

Post by realflow100 »


https://www.telescope.com/Telescopes/Re ... goryId=345 looks like the closest to what im looking for but DANG THATS EXPENSIVEEEEEE

if I saved up and got that I'd have one whopper of a deep sky viewing experience. and also pretty decent for planets too!
Svbony SV503 70mm ED F6 420mm FL refractor telescope (New)
Canon EOS 100D/SL1
Tamron 18-200mm F3.5-F6.3 II VC lens
canon 50mm STM F1.8
svbony 8-24mm zoom eyepiece
svbony goldline 66 degree 9mm and 6mm + 40mm plossl + 2x barlow.
svbony UHC 1.25 filter + astromania 1.25" O-3 filter + also an svbony H-B filter.
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#6

Post by Lady Fraktor »


These are not the largest available nor the most expensive.
If you want quality you have to pay accordingly.
https://www.obsessiontelescopes.com/
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#7

Post by Ngc1514 »


4AE829B0-8814-47E5-BC8A-C8D4B0F64D2C.jpeg
Not sure it’s the largest, but it’s more than I’d care to handle! It’s a Tectron 36 incher called, appropriately, the Yard Scope. Used to be Tom Clark’s scope at Chiefland, but he sold it to Bob Summerfield of “Astronomy To Go.”
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#8

Post by turboscrew »


Go closer to F/6. I have F/4, and everything tends to be expensive. Most eyepieces have difficulties to handle such a steep light cone - that means expensive eyepieces. Like Baader Hyperions are said to be good for F/6 or slower. Also, big aperture means a big minimum magnification. Andomeda galaxy may not fit into the view.
The minimum magnification of my 12" / 1200 mm is about 43X (assuming 7 mm pupil). For me (pupil about 5.5 mm) about 55X. With 50° AFOV that gives TFOV of 0.92°. Bigger tubes are more expensive and tend to need bigger (= more expensive) mount.
My tube costs about 2000 eur and the mount (CEM120 for possible AP) about 4000 eur.
That gives you some idea of cost between the tube and mount when the things get bigger.
(BTW, at the moment 1 eur = 1.21 USD.)

What kind of mount have you thought of? Dobsons make it cheaper, but if you want EQ-mount, the price jumps.
- Juha

Senior Embedded SW Designer
Telescope: OrionOptics XV12, Mount: CEM120, Tri-pier 360 and alternative dobson mount.
Grab 'n go: Omegon AC 102/660 on AZ-3 mount
Eyepieces: 26 mm Omegon SWAN 70°, 15 mm TV Plössl, 12.5 mm Baader Morpheus, 10 mm TV Delos, 6 mm Baader Classic Ortho, 5 mm TV DeLite, 4 mm and 3 mm TV Radians
Cameras: ZWO ASI 294MM Pro, Omegon veLOX 178C
OAG: TS-Optics TSOAG09, ZWO EFW 7 x 36 mm, ZWO filter sets: LRGB and Ha/OIII/SII
Explore Scientific HR 2" coma corrector, Meade x3 1.25" Barlow, TV PowerMate 4x 2"
Some filters (#80A, ND-96, ND-09, Astronomik UHC)
Laptop: Acer Enduro Urban N3 semi-rugged, Windows 11
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#9

Post by turboscrew »


Lady Fraktor wrote: Sun Jun 28, 2020 6:02 pm These are not the largest available nor the most expensive.
If you want quality you have to pay accordingly.
https://www.obsessiontelescopes.com/
One note: High price still doesn't guarantee good quality. Also expensive garbage is being sold.
- Juha

Senior Embedded SW Designer
Telescope: OrionOptics XV12, Mount: CEM120, Tri-pier 360 and alternative dobson mount.
Grab 'n go: Omegon AC 102/660 on AZ-3 mount
Eyepieces: 26 mm Omegon SWAN 70°, 15 mm TV Plössl, 12.5 mm Baader Morpheus, 10 mm TV Delos, 6 mm Baader Classic Ortho, 5 mm TV DeLite, 4 mm and 3 mm TV Radians
Cameras: ZWO ASI 294MM Pro, Omegon veLOX 178C
OAG: TS-Optics TSOAG09, ZWO EFW 7 x 36 mm, ZWO filter sets: LRGB and Ha/OIII/SII
Explore Scientific HR 2" coma corrector, Meade x3 1.25" Barlow, TV PowerMate 4x 2"
Some filters (#80A, ND-96, ND-09, Astronomik UHC)
Laptop: Acer Enduro Urban N3 semi-rugged, Windows 11
LAT 61° 28' 10.9" N, Bortle 5

I don't suffer from insanity. I'm enjoying every minute of it.

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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#10

Post by Lady Fraktor »


turboscrew wrote: Thu Jun 03, 2021 9:40 pm One note: High price still doesn't guarantee good quality. Also expensive garbage is being sold.
Do you have some links to these?
Once you get into the Zambutto, Lockwood and Kennedy prices you have nothing to worry about from the optical side.
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#11

Post by turboscrew »


Lady Fraktor wrote: Thu Jun 03, 2021 9:55 pm
turboscrew wrote: Thu Jun 03, 2021 9:40 pm One note: High price still doesn't guarantee good quality. Also expensive garbage is being sold.
Do you have some links to these?
Once you get into the Zambutto, Lockwood and Kennedy prices you have nothing to worry about from the optical side.
Quality costs, but sometimes bad quality stuff is sold with high prices.
I haven't collected info about bad telescopes, but somehow I don't find telescopes, like this, convincing...
http://www.hioptic.com/telescopes/refle ... Q5_AT5.htm
Neither does this.
https://www.skyatnightmagazine.com/revi ... pe-review/

Oh, and anything from here: http://www.sale-telescopes.com/
(even cheap price is high, if you don't get any products.)
- Juha

Senior Embedded SW Designer
Telescope: OrionOptics XV12, Mount: CEM120, Tri-pier 360 and alternative dobson mount.
Grab 'n go: Omegon AC 102/660 on AZ-3 mount
Eyepieces: 26 mm Omegon SWAN 70°, 15 mm TV Plössl, 12.5 mm Baader Morpheus, 10 mm TV Delos, 6 mm Baader Classic Ortho, 5 mm TV DeLite, 4 mm and 3 mm TV Radians
Cameras: ZWO ASI 294MM Pro, Omegon veLOX 178C
OAG: TS-Optics TSOAG09, ZWO EFW 7 x 36 mm, ZWO filter sets: LRGB and Ha/OIII/SII
Explore Scientific HR 2" coma corrector, Meade x3 1.25" Barlow, TV PowerMate 4x 2"
Some filters (#80A, ND-96, ND-09, Astronomik UHC)
Laptop: Acer Enduro Urban N3 semi-rugged, Windows 11
LAT 61° 28' 10.9" N, Bortle 5

I don't suffer from insanity. I'm enjoying every minute of it.

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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#12

Post by realflow100 »


I think my issue more right now is mostly light pollution issues. rather than size of my scope.

I can very clearly and easily see the background sky is almost a mid-brightness yellowgray color (in terms of the darkest vs lightest things I can see in a scene. Shadows under trees look significantly darker than the sky itself)

its impossible to see orion nebula or andromeda naked eye. Even magnitude 4 stars are well out of my reach!
I can only see stars about magnitude 3 and brighter approximately. even with using averted vision to the best of my abilities. (I have below average eyesight. about 20/40 to 20/50 in either eye I think my left eye is the worse one.)
I can focus fine so its not focusing thats the problem for me.
its everything looks equally blurry/astigmatism at all distances. from 2 inches from my face. a couple feet away. and even the moon at night. all looks about the same amount of blurryness.

my current location where I live is definitely a bortle 9 for me naked eye. and even with optical aid. telescope or binoculars.

With binoculars andromeda galaxy is just a tiny faint fuzzy looking dot. almost looks like a very faint globular cluster (but no distinct stars of course) Barely the very center of the core visible.
and orion nebula is not visible at all

Pleiades is the only naked eye deep sky object I can see. And I can't see any distinct stars in it. looks too fuzzy for me. Siginificantly brightens with averted vision. Almost invisible looking directly at it.
Svbony SV503 70mm ED F6 420mm FL refractor telescope (New)
Canon EOS 100D/SL1
Tamron 18-200mm F3.5-F6.3 II VC lens
canon 50mm STM F1.8
svbony 8-24mm zoom eyepiece
svbony goldline 66 degree 9mm and 6mm + 40mm plossl + 2x barlow.
svbony UHC 1.25 filter + astromania 1.25" O-3 filter + also an svbony H-B filter.
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#13

Post by 25585 »


realflow100 wrote: Sun Jun 28, 2020 1:10 pm I dont like the really long focal length scopes because it makes it really hard to locate a target and center it. and the requirement of an obscenely long focal length eyepiece with humungus AFOV like a 2" 40mm 100*degree eyepiece with a focal reducer

I want to be able to take full advantage of largest exit pupil with 32mm to 20mm eyepiece as well as largest magnification that the telescope is capable of with 6mm eyepiece with or without a 2x barlow

What is a good wide view telescope around F4 to F6 focal ratio of size 8" to 12" that I could buy?
Focal length will increase as aperture does. What's the maximum FL you want?
Unashamed Linda Ronstadt ♡ fan! :dance: :Clap:

Eyepieces from: Aero, Antares, APM, Baader, Brandon, Bresser, Celestron, Datysun, Docter, Explore Scientific, GSO, I R Poyser, Meade, Nikon, Orion, Pentax, Rodenstock, Siberia, Sky-Watcher, Taiso, Takahashi, TAL, Tele Vue, TS, Vernonscope, Vixen, Zeiss.

Scopes from: Altair, Bresser, Lumicon, Orion Optics UK, Sky-Watcher, Takahashi, Tele Vue, TS, Vixen.
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#14

Post by 25585 »


My 10" F6 is 60", same for my 12" F5. Both are solid tube. A 14" F5 would be the max for aperture. 12" F6, 10" F7, 8" F9 are all ones I would like.

Going below F5 makes collimation too fiddly for me, F6 & longer is more tolerant.
Unashamed Linda Ronstadt ♡ fan! :dance: :Clap:

Eyepieces from: Aero, Antares, APM, Baader, Brandon, Bresser, Celestron, Datysun, Docter, Explore Scientific, GSO, I R Poyser, Meade, Nikon, Orion, Pentax, Rodenstock, Siberia, Sky-Watcher, Taiso, Takahashi, TAL, Tele Vue, TS, Vernonscope, Vixen, Zeiss.

Scopes from: Altair, Bresser, Lumicon, Orion Optics UK, Sky-Watcher, Takahashi, Tele Vue, TS, Vixen.
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#15

Post by Bigzmey »


realflow100 wrote: Fri Jun 04, 2021 1:56 am I think my issue more right now is mostly light pollution issues. rather than size of my scope.

I can very clearly and easily see the background sky is almost a mid-brightness yellowgray color (in terms of the darkest vs lightest things I can see in a scene. Shadows under trees look significantly darker than the sky itself)

its impossible to see orion nebula or andromeda naked eye. Even magnitude 4 stars are well out of my reach!
I can only see stars about magnitude 3 and brighter approximately. even with using averted vision to the best of my abilities. (I have below average eyesight. about 20/40 to 20/50 in either eye I think my left eye is the worse one.)
I can focus fine so its not focusing thats the problem for me.
its everything looks equally blurry/astigmatism at all distances. from 2 inches from my face. a couple feet away. and even the moon at night. all looks about the same amount of blurryness.

my current location where I live is definitely a bortle 9 for me naked eye. and even with optical aid. telescope or binoculars.

With binoculars andromeda galaxy is just a tiny faint fuzzy looking dot. almost looks like a very faint globular cluster (but no distinct stars of course) Barely the very center of the core visible.
and orion nebula is not visible at all

Pleiades is the only naked eye deep sky object I can see. And I can't see any distinct stars in it. looks too fuzzy for me. Siginificantly brightens with averted vision. Almost invisible looking directly at it.
Have you considered how are you going to find the targets? I love to star-hop to my targets under dark skies, however under light polluted skies it becomes slow and painful. So, at home I deploy smaller scopes on GoTo mount and this is the route I would suggest. It could be 5-6" reflector, 4-5" refractor or 6-8" SCT. I would go with 8" SCT and use focal reducer if you don't like slow focal ratio.
Scopes: Stellarvue: SV102ED; Celestron: 9.25" EdgeHD, 8" SCT, 150ST, Onyx 80ED; iOptron: Hankmeister 6" Mak; SW: 7" Mak; Meade: 80ST.
Mounts: SW: SkyTee2, AzGTi; iOptron: AZMP; ES: Twilight I; Bresser: EXOS2; UA: MicroStar.
Binos: APM: 100-90 APO; Canon: IS 15x50; Orion: Binoviewer, LG II 15x70, WV 10x50, Nikon: AE 16x50, 10x50, 8x40.
EPs: Pentax: XWs & XFs; TeleVue: Delites, Panoptic & Plossls; ES: 68, 62; Vixen: SLVs; Baader: BCOs, Aspherics, Mark IV.
Diagonals: Baader: BBHS mirror, Zeiss Spec T2 prism, Clicklock dielectric; TeleVue: Evebrite dielectric; AltairAstro: 2" prism.
Filters: Lumicon: DeepSky, UHC, OIII, H-beta; Baader: Moon & SkyGlow, Contrast Booster, UHC-S, 6-color set; Astronomik: UHC.

Observing: DSOs: 3106 (Completed: Messier, Herschel 1, 2, 3. In progress: H2,500: 2180, S110: 77). Doubles: 2382, Comets: 34, Asteroids: 255
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Re: whats the largest F4 to F6 focal ratio scope money can buy?

#16

Post by Mike Q »


Two things, first find darker skies. Light pollution is the enemy no matter what scope you have. Secondly you dont have to spend thousands on the high end works of art when you can spend around a grand on something like an Orion Skyline. A 10 or 12 inch dob would be a lifetime scope and will give you unforgettable views of the night sky. The only real issues are possibly moving it around, and possibly transporting it. Even broken down they are large, but the individual pieces are awkward but not really heavy.
Orion Skyline 10 Inch
Orion XX16G
Stellina
AT102EDL
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