New higher power eyepiece for my scope. Suggestions?

Discuss telescope eyepieces.
User avatar
notFritzArgelander
In Memory
In Memory
Articles: 0
Offline
Posts: 14925
Joined: Fri May 10, 2019 4:13 pm
4
Location: Idaho US
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#41

Post by notFritzArgelander »


turboscrew wrote: Thu Jul 22, 2021 3:25 pm Does this look like a good plan?

Code: Select all

focal length    magnification   exit pupil
26              46              6.50
15              80              3.75
12              100             3.00
8               150             2.00
6               200             1.50
5               240             1.25
4               300             1.00
Yes. The only thing that I think is missing is a 5mm exit pupil 20 mm fl eyepiece. There are a few largish low contrast nebulae for which that’s an essential item.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
User avatar
turboscrew
Inter-Galactic Ambassador
Articles: 0
Offline
Posts: 3233
Joined: Sat Jun 20, 2020 9:22 am
3
Location: Nokia, Finland
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#42

Post by turboscrew »


So, like this?

Code: Select all

focal length    magnification   exit pupil
26              46              6.50
20              60              5.00
15              80              3.75
12              100             3.00
8               150             2.00
6               200             1.50
5               240             1.25
4               300             1.00
- 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.

Image
User avatar
notFritzArgelander
In Memory
In Memory
Articles: 0
Offline
Posts: 14925
Joined: Fri May 10, 2019 4:13 pm
4
Location: Idaho US
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#43

Post by notFritzArgelander »


turboscrew wrote: Thu Jul 22, 2021 3:36 pm So, like this?

Code: Select all

focal length    magnification   exit pupil
26              46              6.50
20              60              5.00
15              80              3.75
12              100            3.00
8               150             2.00
6               200             1.50
5               240             1.25
4               300             1.00
Yes, I’d be happy with that. BTW the largish nebulosity that the 20mm would serve well is in Orion during your prime dark time. I like catching the Horsehead and find that picking it up is easiest at any aperture with a 5mm exit pupil eyepiece. There’s others too.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
User avatar
SkyHiker United States of America
Local Group Ambassador
Articles: 0
Offline
Posts: 2293
Joined: Sat May 11, 2019 8:40 pm
4
Location: Santa Barbara, CA
Status:
Offline

TSS Awards Badges

TSS Photo of the Day

Re: New higher power eyepiece for my scope. Suggestions?

#44

Post by SkyHiker »


I presume you are accounting for using the coma corrector? How does that affect your focal length? My Paracorr II has an adjustable top for visual and turns my 1200 mm into 1380 mm. I am reading that a CC with adjustable top is recommended, especially since each eyepiece requires an exact distance to the CC in order to work well. I am not a visual person myself but I am curious at how eyepieces are discussed in detail while the big elephant in the room is not accounted for. At least, an F/4 Newt has enough coma to consider a CC in the optical path. I would presume that when you buy an expensive eyepiece and want to get the most out of it, you would need to consider how to use the CC in order to get the most out of your eyepiece. Or vice versa, if coma does not bother you, why would you buy expensive eyepieces. Actually here's in interesting thread with Don P chiming in, https://stargazerslounge.com/topic/2674 ... ill-i-see/ .
... Henk. :D Telescopes: GSO 12" Astrograph, "Comet Hunter" MN152, ES ED127CF, ES ED80, WO Redcat51, Z12, AT6RC, Celestron Skymaster 20x80, Mounts and tripod: Losmandy G11S with OnStep, AVX, Tiltall, Cameras: ASI2600MC, ASI2600MM, ASI120 mini, Fuji X-a1, Canon XSi, T6, ELPH 100HS, DIY: OnStep controller, Pi4b/power rig, Afocal adapter, Foldable Dob base, Az/Alt Dob setting circles, Accessories: ZWO 36 mm filter wheel, TV Paracorr 2, Baader MPCC Mk III, ES FF, SSAG, QHY OAG-M, EAF electronic focuser, Plossls, Barlows, Telrad, Laser collimators (Seben LK1, Z12, Howie Glatter), Cheshire, 2 Orion RACIs 8x50, Software: KStars-Ekos, DSS, PHD2, Nebulosity, Photo Gallery, Gimp, CHDK, Computers:Pi4b, 2x running KStars/Ekos, Toshiba Satellite 17", Website:Henk's astro images
User avatar
turboscrew
Inter-Galactic Ambassador
Articles: 0
Offline
Posts: 3233
Joined: Sat Jun 20, 2020 9:22 am
3
Location: Nokia, Finland
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#45

Post by turboscrew »


"To use the HR Coma Corrector visually, at least a displacement of 32mm must be present at the focuser when the focus is on the level of the focuser. For photographic use is critical - the HR Coma Correktor focuses to about 35mm further out."
I didn't find the data.
Without HR, I need to use 50 mm extension to bring any EP to focus.

OH, and "The Explore Scientific Coma Corrector is a class of its own: it is also fully usable visually, and increases the focal length by only 6%."
- 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.

Image
User avatar
Jones
Mars Ambassador
Articles: 0
Offline
Posts: 179
Joined: Tue Jun 23, 2020 12:21 am
3
Location: Arizona
Status:
Offline

Re: New higher power eyepiece for my scope. Suggestions?

#46

Post by Jones »


Forget everything everyone has told you.
You must get the TS Optics UWA 82 degree eyepieces.
You get the big field but these are better on the planets than the Televue Delites. The only things better are the Takahashi TOE's 52 degree for the planets. There are similar ones but they are not nitrogen charged and are a little less good.
20210722_095812.jpg
Arizona- where the sky's are not cloudy all night.

Triple lensed fracs are so yummy when looking at planets.
User avatar
Don Pensack United States of America
Mars Ambassador
Articles: 0
Offline
Posts: 183
Joined: Tue May 25, 2021 8:07 pm
2
Location: Los Angeles, CA
Status:
Offline

Re: New higher power eyepiece for my scope. Suggestions?

#47

Post by Don Pensack »


To be honest, it's hard to see a difference in magnification <30x between eyepieces.
That means the 15mm and 12mm are essentially duplicates.
And you certainly don't need a 20mm for in between the 26mm and 15mm.
A constant magnification change could be: 24mm, 12mm, 8mm, 6mm, 4.8-5mm, 4mm.
26mm is close enough. I don't think you need the 15mm, though having an "extra" eyepiece is OK.
Astronomer since 1963
Currently using a 12.5" dob and a 4" apo refractor
User avatar
notFritzArgelander
In Memory
In Memory
Articles: 0
Offline
Posts: 14925
Joined: Fri May 10, 2019 4:13 pm
4
Location: Idaho US
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#48

Post by notFritzArgelander »


Jones wrote: Thu Jul 22, 2021 5:05 pm Forget everything everyone has told you.
......
That is silly. Mileages vary.
Last edited by notFritzArgelander on Thu Jul 22, 2021 7:31 pm, edited 1 time in total.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
User avatar
notFritzArgelander
In Memory
In Memory
Articles: 0
Offline
Posts: 14925
Joined: Fri May 10, 2019 4:13 pm
4
Location: Idaho US
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#49

Post by notFritzArgelander »


Don Pensack wrote: Thu Jul 22, 2021 6:43 pm To be honest, it's hard to see a difference in magnification <30x between eyepieces.
That means the 15mm and 12mm are essentially duplicates.
And you certainly don't need a 20mm for in between the 26mm and 15mm.
A constant magnification change could be: 24mm, 12mm, 8mm, 6mm, 4.8-5mm, 4mm.
26mm is close enough. I don't think you need the 15mm, though having an "extra" eyepiece is OK.
Yeah, I just don't buy constant magnification change as a good guiding principle. Apart from a 5mm exit pupil being essential for some objects really old folks find that 6mm exit pupil might be a good aperture stop if they can only dilate to 5mm. Fortunately I'm not that old yet and can still find a 6mm exit pupil useful.

I still find exit pupil increments at the long end and focal length increments shorter than 2mm exit pupil to be a better principle for optimizing by object and sky conditions both. Constant magnification increments might make an adequate minimalist set but it won't optimize performance. YMMV.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
User avatar
Bigzmey United States of America
Moderator
Moderator
Articles: 8
Online
Posts: 7550
Joined: Sat May 11, 2019 7:55 pm
4
Location: San Diego, CA USA
Status:
Online

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#50

Post by Bigzmey »


turboscrew wrote: Thu Jul 22, 2021 3:36 pm So, like this?

Code: Select all

focal length    magnification   exit pupil
26              46              6.50
20              60              5.00
15              80              3.75
12              100             3.00
8               150             2.00
6               200             1.50
5               240             1.25
4               300             1.00
Looks reasonable. There is a bit of redundancy, but since your 6mm and 15mm are minimal glass 50 deg EPs having 12mm and 5mm wide field long eye relief EPs would still be useful. Alternatively, you may decide to split the difference between 15mm and 6mm and get just one EP in the middle (10-11mm).
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
User avatar
Bigzmey United States of America
Moderator
Moderator
Articles: 8
Online
Posts: 7550
Joined: Sat May 11, 2019 7:55 pm
4
Location: San Diego, CA USA
Status:
Online

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#51

Post by Bigzmey »


notFritzArgelander wrote: Thu Jul 22, 2021 7:22 pm
Jones wrote: Thu Jul 22, 2021 5:05 pm Forget everything everyone has told you.
......
That is silly. Mileages vary.
I thought it was a friendly poke, no? ;)
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
User avatar
notFritzArgelander
In Memory
In Memory
Articles: 0
Offline
Posts: 14925
Joined: Fri May 10, 2019 4:13 pm
4
Location: Idaho US
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#52

Post by notFritzArgelander »


Bigzmey wrote: Thu Jul 22, 2021 7:34 pm
notFritzArgelander wrote: Thu Jul 22, 2021 7:22 pm
Jones wrote: Thu Jul 22, 2021 5:05 pm Forget everything everyone has told you.
......
That is silly. Mileages vary.
I thought it was a friendly poke, no? ;)
Hopefully so. I may be running a sense of humor deficit today having had a bad night of insomnia without compensating fun. Maybe I'll take a nap. ;)
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
User avatar
Bigzmey United States of America
Moderator
Moderator
Articles: 8
Online
Posts: 7550
Joined: Sat May 11, 2019 7:55 pm
4
Location: San Diego, CA USA
Status:
Online

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#53

Post by Bigzmey »


notFritzArgelander wrote: Thu Jul 22, 2021 7:28 pm
Don Pensack wrote: Thu Jul 22, 2021 6:43 pm To be honest, it's hard to see a difference in magnification <30x between eyepieces.
That means the 15mm and 12mm are essentially duplicates.
And you certainly don't need a 20mm for in between the 26mm and 15mm.
A constant magnification change could be: 24mm, 12mm, 8mm, 6mm, 4.8-5mm, 4mm.
26mm is close enough. I don't think you need the 15mm, though having an "extra" eyepiece is OK.
Yeah, I just don't buy constant magnification change as a good guiding principle. Apart from a 5mm exit pupil being essential for some objects really old folks find that 6mm exit pupil might be a good aperture stop if they can only dilate to 5mm. Fortunately I'm not that old yet and can still find a 6mm exit pupil useful.

I still find exit pupil increments at the long end and focal length increments shorter than 2mm exit pupil to be a better principle for optimizing by object and sky conditions both. Constant magnification increments might make an adequate minimalist set but it won't optimize performance. YMMV.
Going by exit pupil seems to work consistently for me, no matter what scope I am using, so I am going by exit pupil now and just adding one or two EPs in between if need arises.
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
User avatar
turboscrew
Inter-Galactic Ambassador
Articles: 0
Offline
Posts: 3233
Joined: Sat Jun 20, 2020 9:22 am
3
Location: Nokia, Finland
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#54

Post by turboscrew »


Jones wrote: Thu Jul 22, 2021 5:05 pm Forget everything everyone has told you.
You must get the TS Optics UWA 82 degree eyepieces.
You get the big field but these are better on the planets than the Televue Delites. The only things better are the Takahashi TOE's 52 degree for the planets. There are similar ones but they are not nitrogen charged and are a little less good.

Image
I just wonder how well it works with F/4. I know Baader Hyperions don't work well with F-number lower than 6.
Last edited by turboscrew on Thu Jul 22, 2021 8:59 pm, edited 1 time in total.
- 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.

Image
User avatar
turboscrew
Inter-Galactic Ambassador
Articles: 0
Offline
Posts: 3233
Joined: Sat Jun 20, 2020 9:22 am
3
Location: Nokia, Finland
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#55

Post by turboscrew »


Bigzmey wrote: Thu Jul 22, 2021 7:33 pm
turboscrew wrote: Thu Jul 22, 2021 3:36 pm So, like this?

Code: Select all

focal length    magnification   exit pupil
26              46              6.50
20              60              5.00
15              80              3.75
12              100             3.00
8               150             2.00
6               200             1.50
5               240             1.25
4               300             1.00
Looks reasonable. There is a bit of redundancy, but since your 6mm and 15mm are minimal glass 50 deg EPs having 12mm and 5mm wide field long eye relief EPs would still be useful. Alternatively, you may decide to split the difference between 15mm and 6mm and get just one EP in the middle (10-11mm).
That's the catch. I already have 26 mm, 15 mm and 6 mm. 5 mm is ordered, but it hasn't arrived yet. Well, I also have 25 mm and 10 mm, but they are the cheapest Kellners I could find (my very first EPs), so I'm not considering them as part of my set any more. Just haven't removed them from my signature yet.
Also, I made a poll on the biggest Finnish astronomy club ( https://www.ursa.fi/english.html ) about the maximum useful magnification. According to them, it's about 250x. 300x very seldom, so I decided to get a 5 mm (240x) eyepiece.
(There are not so many 4.8 mm eyepieces around to select from.)

Also my 3x Barlow is the cheapest I could find (got it together with the Kellners).

My idea was going ad hoc with the current good EPs and taking into account both magnifications and exit pupils.
The purchasing order and time are another matter.
- 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.

Image
User avatar
turboscrew
Inter-Galactic Ambassador
Articles: 0
Offline
Posts: 3233
Joined: Sat Jun 20, 2020 9:22 am
3
Location: Nokia, Finland
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#56

Post by turboscrew »


Would it be bad idea, if, instead of 12 mm and 8 mm, I'd get only 9 mm (133x, 2.25 mm exit pupil)?
- 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.

Image
User avatar
notFritzArgelander
In Memory
In Memory
Articles: 0
Offline
Posts: 14925
Joined: Fri May 10, 2019 4:13 pm
4
Location: Idaho US
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#57

Post by notFritzArgelander »


turboscrew wrote: Thu Jul 22, 2021 9:24 pm Would it be bad idea, if, instead of 12 mm and 8 mm, I'd get only 9 mm (133x, 2.25 mm exit pupil)?
Not a bad idea. The 15mm will be useful for galaxy hunting.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker IV, Vixen Porta II, Celestron CG5
User avatar
Bigzmey United States of America
Moderator
Moderator
Articles: 8
Online
Posts: 7550
Joined: Sat May 11, 2019 7:55 pm
4
Location: San Diego, CA USA
Status:
Online

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#58

Post by Bigzmey »


turboscrew wrote: Thu Jul 22, 2021 9:24 pm Would it be bad idea, if, instead of 12 mm and 8 mm, I'd get only 9 mm (133x, 2.25 mm exit pupil)?
That would work. Are you thinking 9mm Delite?
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
User avatar
turboscrew
Inter-Galactic Ambassador
Articles: 0
Offline
Posts: 3233
Joined: Sat Jun 20, 2020 9:22 am
3
Location: Nokia, Finland
Status:
Offline

TSS Awards Badges

Re: New higher power eyepiece for my scope. Suggestions?

#59

Post by turboscrew »


Bigzmey wrote: Thu Jul 22, 2021 10:59 pm
turboscrew wrote: Thu Jul 22, 2021 9:24 pm Would it be bad idea, if, instead of 12 mm and 8 mm, I'd get only 9 mm (133x, 2.25 mm exit pupil)?
That would work. Are you thinking 9mm Delite?
I wasn't thinking anything specific. But I came to realize, there are not too many good 9 mm options.
- 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.

Image
User avatar
Don Pensack United States of America
Mars Ambassador
Articles: 0
Offline
Posts: 183
Joined: Tue May 25, 2021 8:07 pm
2
Location: Los Angeles, CA
Status:
Offline

Re: New higher power eyepiece for my scope. Suggestions?

#60

Post by Don Pensack »


This might help in looking for eyepieces of a particular focal length:
https://www.cloudynights.com/topic/7583 ... p=10917573

As for selecting by exit pupil, lots of discussions suggest a 40% difference might be optimum. Less than that, and the brightness difference might not be noticeable.
If we start with a 6mm exit pupil, the exit pupil progression is: 6.0mm, 4.6mm, 3.6mm, 2.8mm, 2.2mm, 1.7mm, 1.3mm, 1.0mm, 0.8mm, 0.6mm
Now that may be a bigger set of eyepieces than you want, and it will put the eyepieces really close together in magnification at the low end.

If all your eyepieces have the same apparent field, you can get smooth decreases in field area of 50% between eyepieces by dividing the focal lengths by 1.414
To wit: 30mm, 21.2mm, 15.0mm, 10.6mm, 7.5mm, 5.3mm. We can round off to a set of 30, 21, 15, 11, 8, 5mm, a 6-eyepiece set.
There are many ways to choose eyepieces. And if you buy too few, buy another. Too many? Sell one or more.
One truth: you cannot buy a set of eyepieces today you will find optimum in 10 years. So just take the plunge.
Astronomer since 1963
Currently using a 12.5" dob and a 4" apo refractor
Post Reply

Create an account or sign in to join the discussion

You need to be a member in order to post a reply

Create an account

Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute

Register

Sign in

Return to “Eyepieces”