DOB Vs Refractor for planetary viewing

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notFritzArgelander
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Re: DOB Vs Refractor for planetary viewing

#21

Post by notFritzArgelander »


Richard wrote: Fri Jan 24, 2020 3:17 pm
notFritzArgelander wrote: Thu Jan 23, 2020 5:55 pm
Richard wrote: Thu Jan 23, 2020 2:55 pm 100% a Mak is probably the best for planets given the size but there are not many to look at , one can only look at Saturn, Jupiter and Mars (sometimes) nice and the rest is so so , so unless you are fixated with these 2-3 planets then look at a more useful scope like a Dobs
Only is way too strong! I'm very happy with DSO views with my MK66 full aperture corrector Rumak Mak at f12 and my sub aperture corrector f10 VMC110L. The littler one takes a 0.5x focal reducer very nicely too and is an excellent grab and go kit for general viewing.
Yes any scope can be modified for other uses but in my opinion a Mac is a planetary scope just like a long focal length refractor like my Tasco ,good for planets, double stars and globs but without modification (reducer etc) not good for DSO, but honestly most people will not see DSO due to the LP in their area, probably 95% , few of us live in a low LP area
We'll have to agree to disagree then. Even unmodified a Mak is excellent on DSOs. The same factors that are good for planets (good contrast) are good for rendering details in nebulae. For cutting through LP the smaller exit pupils on Maks make that an easier task than with Dobs. If LP is a problem, use a Mak.
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
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Re: DOB Vs Refractor for planetary viewing

#22

Post by Bigzmey »


notFritzArgelander wrote: Fri Jan 24, 2020 4:05 pm
Richard wrote: Fri Jan 24, 2020 3:17 pm
notFritzArgelander wrote: Thu Jan 23, 2020 5:55 pm

Only is way too strong! I'm very happy with DSO views with my MK66 full aperture corrector Rumak Mak at f12 and my sub aperture corrector f10 VMC110L. The littler one takes a 0.5x focal reducer very nicely too and is an excellent grab and go kit for general viewing.
Yes any scope can be modified for other uses but in my opinion a Mac is a planetary scope just like a long focal length refractor like my Tasco ,good for planets, double stars and globs but without modification (reducer etc) not good for DSO, but honestly most people will not see DSO due to the LP in their area, probably 95% , few of us live in a low LP area
We'll have to agree to disagree then. Even unmodified a Mak is excellent on DSOs. The same factors that are good for planets (good contrast) are good for rendering details in nebulae. For cutting through LP the smaller exit pupils on Maks make that an easier task than with Dobs. If LP is a problem, use a Mak.
It comes down to the type of DSOs. If it is a large target, or target which requires a large exit pupil, then yes slow Mac/SCT/frac would not do. For open clusters which tends to spread out and extended defuse nebulae (low SB, large size, large exit pupil for filters) my weapon of choice is 150mm F5 achro.

But for small faint DSOs (like majority of galaxies) or planetary nebulae (need sharp focus at high powers) I actually prefer slow scopes.
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: DOB Vs Refractor for planetary viewing

#23

Post by Baurice »


I used a 127mm Mak with a 0.5x focal reducer. Although I sometimes needed a light pollution filter, I managed to bag all Messier objects.

But I use it mainly for the Moon and planets. I also use it for the Sun but the solar disc has been sunspot-free recently.
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Lady Fraktor Slovakia
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Re: DOB Vs Refractor for planetary viewing

#24

Post by Lady Fraktor »


helicon wrote: Thu Jan 23, 2020 6:14 pm
Well, I can set it up myself but there is always that moment when I sling the OTA into the dovetail with one hand and then tighten the locking knob with the other hand (Twilight II). I almost dropped the scope once. So if I have folks over for dinner I usually set up the scope, hold the OTA with two hands and have someone tighten the knob for me. (sister, nephew or whomever). Otherwise I do it myself.
:)
Here is how a short person does it :)

Once the mount is set up turn the RA axis till the counterweight shaft is horizontal and lock the clutch ( I have a mark on the mount and dovetail that indicates my balance point)
Make sure the dovetail tightening screw is pointing up.
Cradle the telescope in both arms and step up to the mount placing the dovetail into the saddle. Tighten the screw with either hand.
Unlock the clutch and enjoy. :)

Doing this you have full control of the telescope tube and when you set it into the mount saddle the dovetail will be resting on the solid jaw already.
If it is a heavier tube with a handle you can help lift with one hand while tightening the holding screw with the other.

This can make it easier for anyone that has a hard time mounting a larger telescope on an EQ mount.
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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coopman United States of America
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Re: DOB Vs Refractor for planetary viewing

#25

Post by coopman »


FOV is also dependent on whether the scope has a focuser that accepts 2" eyepieces. Some 6" Dobs don't have that (stock).
You can get an 8" or 10" Dob for what the 6" achro will cost, and the Dob will most likely provide a better image. "Aperture is king" as they say, as long as you can handle the weight of the scope & its mount.
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