Upgrading your astro equipment

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Bigzmey United States of America
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Upgrading your astro equipment

#1

Post by Bigzmey »


When and how to upgrade? People have written books on this subject. :) We all want to get maximal return on the investment and that's where discussions often heat up. "My no name $15 EP is as good as $300 Televue" or "Televue or nothing" - you see both statements quite often. Surprisingly, both could be correct. Because you need to consider all optical setup, not just EP.

After years of researching, testing and upgrading equipment I came with a few rules of thumb which seem to work surprisingly well. I don't claim that this is the only or the best way, but it works. I like to hear about your upgrading strategies as well.

1) You always start with telescope, this is where you get the most return on your investment. Weather your next scope has larger aperture or better optics, or both - that's where your money should go first.

2) Mount, as important as scope. Shaky mount will kill any benefits from telescope upgrades. Unfortunately, I see it all the time when people focus on the scope upgrades neglecting mounts. Big mistake! So, when you plan for the telescope upgrade always allocate founds to get the mount which carry the scope well.

3) EPs. Do I need $15 or $300 EP? My rule of thumb - don't spend on EPs more than you spent on the scope. Just to give you an example. My back to hobby scope was $300 90mm refractor on AltAz mount. I learned quite fast that EPs that came with the scope are not good and upgraded to Celestron X-Cel LX, ~$70 a piece. Later I discovered that $60 Dual EDs work as well as X-Cel LX in 80-100mm scopes. I saw clear improvement in the views and reach of the scope. They served my needs well until I have upgraded the scope to ~$800 8" SCT. Suddenly, the views at high powers became soft and other imperfections became evident. Upgrading to ES82 ~$150 a piece have fixed the issue. Could I have purchased ES82 for 90mm scope? Sure! Would I see as evident improvement in the view quality as with 8" SCT? Likely not. I would probably be one of those guys writing "ES82 - what a rip off!" :lol: Even if I liked ES82 the performance improvement of dropping $800 on the set of ES82 with 90mm scope is much smaller then getting 8" SCT and keeping Celestron X-Cel LX set.

4) Diagonal. Not applicable to reflectors, but for CATs and refractors it is as important as EPs. My rule of thumb match diagonal price to your most expensive EP. For 8" SCT I have upgraded to ~$150 2" dielectric and later added ~$160 T2 prism. When I moved to 9.25" Edge HT SCT I went with Baader premium diagonals and Pentax/TV EPs. Again, matching diagonal to EPs, and EPs to scope. Would I recommend $300 Baader diagonal for $300 scope? Nope.

To sum up, my recommendation would be basic $15-30 EPs (Plossls and such) for $100 scopes, $40-70 EPs for ~$300 scopes, $80-200 EPs for $1000, and so on. Can you buy $300 EP for $100 scope? Absolutely! But, you will get much larger performance gain by getting $300 scope instead.

When, I was doing all these upgrades I did not go by EP prices, it is now looking back I have discovered that I seem to always end up matching EP set price to the scope price.

Your thoughts?
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: Upgrading your astro equipment

#2

Post by turboscrew »


Agree. You buy a big fast scope, and you realize, everything is expensive.
The prices of mounts grow much faster than their load rating (and so does the weight).
For an F/6 scope or slower, you can choose between different eyepieces, but faster scopes require better corrected - and more expensive - ones. Last year there were many eyepiece series with notes like "crisp view with F/6 or higher" or "works very well with F/5 or slower". Now the se notes have disappeared, and choosing an eyepiece has become harder.
And the smaller the F-number is, the more expensive the eyepiece tends to be.

Also. get big aperture for light only. In theory you can use much bigger magnifications with bigger apertures, but in practice, the atmosphere limits the generally usable resolution to <= 300x.
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Re: Upgrading your astro equipment

#3

Post by Bigzmey »


turboscrew wrote: Wed Jul 21, 2021 10:36 pm Also. get big aperture for light only. In theory you can use much bigger magnifications with bigger apertures, but in practice, the atmosphere limits the generally usable resolution to <= 300x.
Definitely something to consider. On faint galaxies it is very easy to see advantage of 9.25" SCT over 4" refractor. In theory 9.25" SCT also should provide more detailed views of planets. In practice it is often not the case. Last year the seeing was bad and on average night 4" frac has delivered similar and sometimes even better views of Jupiter and Saturn.
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: Upgrading your astro equipment

#4

Post by pakarinen »


Interesting!
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Re: Upgrading your astro equipment

#5

Post by Baurice »


I always agreed that there's no point in buying expensive eyepieces for cheap telescopes. I would add a couple of points:

1. A good pair of binoculars will see far more use than an expensive telescope

2. Many or most of us will stop using eyepieces or only use them rarely and get into photography instead. I use my DSLR on its own more than I use it with a telescope and it is only when the planets are around that I use a telescope for visual use.
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Re: Upgrading your astro equipment

#6

Post by Ylem »


A decent diagonal is imperative with an SCT/Mak. Nothing worse than performing collimation, then add the diagonal and it appears off.
Just chasing your tail.
This holds true for refractors I guess.

Also a decent finder is absolutely necessary :)
I love unity finders myself. :)
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Re: Upgrading your astro equipment

#7

Post by SpyderwerX »


Ylem wrote: Fri Jul 23, 2021 12:02 am A decent diagonal is imperative with an SCT/Mak. Nothing worse than performing collimation, then add the diagonal and it appears off.
Just chasing your tail.
This holds true for refractors I guess.

Also a decent finder is absolutely necessary :)
I love unity finders myself. :)
I second that notion on diagonals. I tend to pay as much attention to, if not sometimes more, the diagonal than the EPs. :)
~Frankie~ My mind: Always on...Slightly off. :?
Celestron CPC1100 SCT....Celestron Evolution 8 SCT...TeleVue-85 apo...SkyWatcher ST150 achro..ST102 achro..ST80 achro.
Celestron AVX...Orion Atlas EQ-G...SkyTee-2...Twilight-1.
Baader BBHS prism and mirror diagonals + Vernonscope quartz 1.25"
EPs: TeleVue oldie (NJ) & modern Plossls, Widefields, and Naglers + 3-6 zoom & Brandons 6-32.
Astronomik, Lumicon & Baader filters..
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Re: Upgrading your astro equipment

#8

Post by Bigzmey »


SpyderwerX wrote: Fri Jul 23, 2021 12:21 am
Ylem wrote: Fri Jul 23, 2021 12:02 am A decent diagonal is imperative with an SCT/Mak. Nothing worse than performing collimation, then add the diagonal and it appears off.
Just chasing your tail.
This holds true for refractors I guess.

Also a decent finder is absolutely necessary :)
I love unity finders myself. :)
I second that notion on diagonals. I tend to pay as much attention to, if not sometimes more, the diagonal than the EPs. :)
Hear hear! :) And it is not just collimation. Contrast and resolution could be lost to light scatter on mediocre mirrors. Also budget diagonals (and sometimes not so budget) tend to have reduced clear aperture. People buy 2" diagonals to benefit from wide views of 2" EPs, but don't realize that quite few of those diagonals have open apertures smaller than 2" EPs field stops.

Can't leave home without a couple of good finders (RACI and reddot). :) Funny thing though. while I enjoy better quality RACIs, I prefer very basic $10 red dots over fancier reflex sight designs.
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: Upgrading your astro equipment

#9

Post by Baurice »


Ylem wrote: Fri Jul 23, 2021 12:02 am A decent diagonal is imperative with an SCT/Mak. Nothing worse than performing collimation, then add the diagonal and it appears off.
Just chasing your tail.
This holds true for refractors I guess.

Also a decent finder is absolutely necessary :)
I love unity finders myself. :)
Good bit of advice I haven't followed. I remove mine for photographic use but night not need to if I need one.
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Re: Upgrading your astro equipment

#10

Post by Baurice »


Also, just reminded me, I bought a 9x50 RA finderscope. Much better than 6x30 straight through or telrad/red dot. I even saw M33 from a dark site through mine.
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Re: Upgrading your astro equipment

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Post by Makuser »


Hi Andrey and all. Boy this a great thread. I am in complete agreement with all of you. Back in 1974, I bought a Jason (rebranded Tasco?) 60mm f/11 refractor scope. It came with two Japanese standard .965" eyepieces (Achromatic Ramsden and Huygens). Later, I purchased a .965" to 1.25" adapter from University Optics and 1.25" 16mm Konig and a 1.25" 32mm Plossl eyepiece from A.E. Jaeger . Wow, what a difference in the views. I spent months on any clear night taking Moon Walks and I wore out my old Sky &Telescope lunar map, as you see.
Old Lunar Map.JPG
However later, the telescope manufacture's decided; "Why sell quality scopes and include inferior eyepieces"? Today, the market features scopes that come with 1.25" 25mm Plossl eyepeices and sometimes also a 10mm eyepiece in the package. Plossl eyepieces are very good and I have several myself. And, you can add to your collection over time to fill a focal length gap that you think that you might need. As to eyepiece quality, I always try to get the best that I can afford, look for sales and free shipping. The only thing to add here, is that I use 2" eyepieces on my 6" f/5 refractor, and being a short focal length Fraunhofer doublet, it is somewhat sensitive to lesser quality eyepieces.
As to the finderscopes, I am so happy with the RACI finders on my scopes. Now, I don't have to twist my neck with a straight through finder and then go back to the eyepiece. When I first got a 9x50 RACI, I was amazed at what I could see just with it. Then you have to remember, the 50mm objective comes close to a 60mm telescope. Also, I use dielectric diagonals on my refractor and Mak-Cass scopes.
Andrey, back in 2000 I bought I bought a complete kit at Books A Million for just $16 on sale. The kit was by Robin Scagell, who is a long-serving Vice President of Britain's Society for Popular Astronomy.
AStroBooks5.JPG
Here is a more detailed explanation about why sometimes a smaller aperture scope can perform better, from Robin Scagell's book "The Night Sky Through Your Telescope:
Scagell1.jpg
I hope that I have added something to the discussion on here, and the best of regards to all.
Marshall
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Re: Upgrading your astro equipment

#12

Post by Bigzmey »


Hi Marshall. My first "real" scope does not go as far back as yours. However even in early 90s entry level scopes came with less plastic, better mounts and EPs. But, as you I don't miss those straight through finders. Thanks god for RACIs and red dots! :lol:
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: Upgrading your astro equipment

#13

Post by mikemarotta »


My other hobby is numismatics and we have these challenge questions, too. Some collectors only want the highest Mint states and certfied by a top-tier grading company. And that's OK, but the discussion then turns on someone posting a classic 19th century silver half-crown, like a US half dollar or a UK florin with nice, even wear, and you know that the coin has historicity: it had a life. For myself, I pursued archaic and classical Greek coins from the towns and times of philosophers and had about 50 from Thales to Hypatia. An uncirculated coin would be nice to look at, have all the details, but would lack historicity: it never did any work for anyone, never bought a krater of wine or a loaf of bread. On that basis, some people collect gold of the 12 Caesars, again, nice coins, but a bronze semis or quadrante answers the sign at the tavern: Nulla mensa sine impensa.
  • So,my first axiom is that the best telescope is the one that gets used.
    And my second is that good seeing is more important than good glass.
I have a new 8-inch Newtonian and a new 115mm APO refractor, both in boxes for want of other hardware. I need finders that fit and I need tripods and mounts that can carry the loads. The Newtonian is a Bresser that I bought from Explore Scientific. Their customer service rep said: "We do not have anything that fits this finder base perfectly because we make them to be universal." As for the mount and tripod, the Newt only weighs 10kg (22 lbs), and the frac 17 lbs (like 7.75 kg), but right now, all accessories are hard to find. So, the nominally "best" telescopes are just not getting used right now and it will be clear tonight. So, I am taking out the 102mm achromatic doublet refractor with my kit of Celestron Ploessls, not the others with the Televue 82-degree 7 mm and Meade 82-degee 14 mm.
Bigzmey wrote: Wed Jul 21, 2021 9:04 pm 1) You always start with telescope ...
2) Mount, as important as scope. ...
Right and if the mount is just as important then it could be Number 1. We all each and everyone of us focus on the telescope and then say, "... but the mount..." Why not start with the mount? That would be my advice for anyone asking about their second telescope. The first telescope can be almost anything (above a basic level). I still take my 70 mm National Geographic out for short trips in the backyard, just to see what I can see. I don't take it out more often because the mount is held together with rubber bands. If I did this all over again, for my second telescope I would shop long and hard for a mount and tripod first. Those are harder to find and as noted by Turboscrew, they get expensive on a curve steeper than the telescope.
Bigzmey wrote: Wed Jul 21, 2021 9:04 pm ... My rule of thumb - don't spend on EPs more than you spent on the scope.
Baurice wrote: Thu Jul 22, 2021 10:11 pm I always agreed that there's no point in buying expensive eyepieces for cheap telescopes. I would add a couple of points:
1. A good pair of binoculars will see far more use than an expensive telescope
I know from looking back at my logs that last year at this time when we were shut down for Covid, my city skies were much clearer. I split the double-double in epsilon Lyrae and split delta Scorpii, among other targets. Last week, I got out for a few hours from 10:00 to 02:00 and neither was attainable with the same instrumentation.

To solve the problem of good seeing, you cannot buy enough telescope. We are moving. Our neighborhood is getting built up. We have been here almost eight years. We rent. So, we're looking to move. And, I have a map of the 2023-2024 annular and total eclipses. We have a lot of choices.

I agree 100% on the binoculars. They get hard to hold. And I am older and shakier and I was never agile or adroit but it is nice to use them to verify locations and targets and mostly, just to lay back in the chaise lounge and look up at the sky.
Makuser wrote: Fri Jul 23, 2021 6:12 pm ... I spent months on any clear night taking Moon Walks and I wore out my old Sky &Telescope lunar map, as you see. ... Andrey, back in 2000 I bought I bought a complete kit at Books A Million ...
And that's another great example of "outside the box thinking." I had a nice telescope as a kid, a 4-inch reflector. I never saw much with it, maybe the Moon a couple of times. My first view of Saturn, what got me hooked, was with my first telescope, a Tasco 30x30 birdwatcher. But someone showed me that. We lived near city hospital and we had young doctors as renters in the neighborhood and one night they were partying and one of them pointed to Saturn and told me to get my telescope.

Now, my mentors are books and I do a lot of shopping, just window shopping and reading looking for the ones that work best for me. That includes planispheres. I have several and one I like best. I am happy that the city library is open again and I have been using curbside pickup for several months now.

And then there's websites. I rely on Sky & Telescope but use others as well.
Sky tonight
https://skyandtelescope.org/interactive-sky-chart/

Jupiter's moons
https://skyandtelescope.org/wp-content/ ... piter.html

The Great Red Spot
https://skyandtelescope.org/observing/i ... -red-spot/

Saturn and its moons
https://skyandtelescope.org/wp-content/ ... aturn.html

Mars (when it comes around again)
https://skyandtelescope.org/wp-content/ ... /mars.html

And, finally, I mentioned taking an online class in astrophysics and I am looking at another. In addition to a standard university textbook and some other classroom materials that I acquired over the years, I recently bought Steven Weinberg's overview lectures.
Weinberg Astrophysics (cover) copy.jpeg
And another textbook for a one-year class.
9781108422161.jpg
9781108422161.jpg (12.49 KiB) Viewed 3620 times
It does not matter what kind of telescope you have, or what your oculars are, or the magnification of your finderscope, or the load bearing limit of your mount and tripod. If you do not understand what you are looking at, why are you out there?
---------------------------------------
Michael E. Marotta
Astro-Tech 115 mm APO Refractor Explore Scientific 102 mm f/6.47 Refractor Explore Scientific 102 mm f/9.8 Refractor Bresser 8-inch Newtonian Reflector Plössls from 40 to 6 mm Nagler Series-1 7mm. nonMeade 14 mm. Mounts: Celestron AVX, Explore Twilight I Alt-Az, Explore EXOS German Equatorial
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Re: Upgrading your astro equipment

#14

Post by Bigzmey »


mikemarotta wrote: Fri Jul 23, 2021 11:05 pm
Bigzmey wrote: Wed Jul 21, 2021 9:04 pm 1) You always start with telescope ...
2) Mount, as important as scope. ...
Right and if the mount is just as important then it could be Number 1. We all each and everyone of us focus on the telescope and then say, "... but the mount..." Why not start with the mount? That would be my advice for anyone asking about their second telescope.
Telescope is #1 because you can't observe with mount alone. With telescope you can, even if holding it in your hands. :D

More seriously, it makes sense to match mount to scope. When I decided to buy 102mm ED scope I did not get AVX. Why pay extra and haul extra weight when 102mm rides nicely on compact and lightweight AZGti? However, if I would buy AZGti first without settling on the scope I could miss the mark since it has only 11lb capacity.
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: Upgrading your astro equipment

#15

Post by turboscrew »


mikemarotta wrote: Fri Jul 23, 2021 11:05 pm My other hobby is numismatics and we have these challenge questions, too. Some collectors only want the highest Mint states and certfied by a top-tier grading company. And that's OK, but the discussion then turns on someone posting a classic 19th century silver half-crown, like a US half dollar or a UK florin with nice, even wear, and you know that the coin has historicity: it had a life. For myself, I pursued archaic and classical Greek coins from the towns and times of philosophers and had about 50 from Thales to Hypatia. An uncirculated coin would be nice to look at, have all the details, but would lack historicity: it never did any work for anyone, never bought a krater of wine or a loaf of bread. On that basis, some people collect gold of the 12 Caesars, again, nice coins, but a bronze semis or quadrante answers the sign at the tavern: Nulla mensa sine impensa.
  • So,my first axiom is that the best telescope is the one that gets used.
    And my second is that good seeing is more important than good glass.
I have a new 8-inch Newtonian and a new 115mm APO refractor, both in boxes for want of other hardware. I need finders that fit and I need tripods and mounts that can carry the loads. The Newtonian is a Bresser that I bought from Explore Scientific. Their customer service rep said: "We do not have anything that fits this finder base perfectly because we make them to be universal." As for the mount and tripod, the Newt only weighs 10kg (22 lbs), and the frac 17 lbs (like 7.75 kg), but right now, all accessories are hard to find. So, the nominally "best" telescopes are just not getting used right now and it will be clear tonight. So, I am taking out the 102mm achromatic doublet refractor with my kit of Celestron Ploessls, not the others with the Televue 82-degree 7 mm and Meade 82-degee 14 mm.
Bigzmey wrote: Wed Jul 21, 2021 9:04 pm 1) You always start with telescope ...
2) Mount, as important as scope. ...
Right and if the mount is just as important then it could be Number 1. We all each and everyone of us focus on the telescope and then say, "... but the mount..." Why not start with the mount? That would be my advice for anyone asking about their second telescope. The first telescope can be almost anything (above a basic level). I still take my 70 mm National Geographic out for short trips in the backyard, just to see what I can see. I don't take it out more often because the mount is held together with rubber bands. If I did this all over again, for my second telescope I would shop long and hard for a mount and tripod first. Those are harder to find and as noted by Turboscrew, they get expensive on a curve steeper than the telescope.
Bigzmey wrote: Wed Jul 21, 2021 9:04 pm ... My rule of thumb - don't spend on EPs more than you spent on the scope.
Baurice wrote: Thu Jul 22, 2021 10:11 pm I always agreed that there's no point in buying expensive eyepieces for cheap telescopes. I would add a couple of points:
1. A good pair of binoculars will see far more use than an expensive telescope
I know from looking back at my logs that last year at this time when we were shut down for Covid, my city skies were much clearer. I split the double-double in epsilon Lyrae and split delta Scorpii, among other targets. Last week, I got out for a few hours from 10:00 to 02:00 and neither was attainable with the same instrumentation.

To solve the problem of good seeing, you cannot buy enough telescope. We are moving. Our neighborhood is getting built up. We have been here almost eight years. We rent. So, we're looking to move. And, I have a map of the 2023-2024 annular and total eclipses. We have a lot of choices.

I agree 100% on the binoculars. They get hard to hold. And I am older and shakier and I was never agile or adroit but it is nice to use them to verify locations and targets and mostly, just to lay back in the chaise lounge and look up at the sky.
Makuser wrote: Fri Jul 23, 2021 6:12 pm ... I spent months on any clear night taking Moon Walks and I wore out my old Sky &Telescope lunar map, as you see. ... Andrey, back in 2000 I bought I bought a complete kit at Books A Million ...
And that's another great example of "outside the box thinking." I had a nice telescope as a kid, a 4-inch reflector. I never saw much with it, maybe the Moon a couple of times. My first view of Saturn, what got me hooked, was with my first telescope, a Tasco 30x30 birdwatcher. But someone showed me that. We lived near city hospital and we had young doctors as renters in the neighborhood and one night they were partying and one of them pointed to Saturn and told me to get my telescope.

Now, my mentors are books and I do a lot of shopping, just window shopping and reading looking for the ones that work best for me. That includes planispheres. I have several and one I like best. I am happy that the city library is open again and I have been using curbside pickup for several months now.

And then there's websites. I rely on Sky & Telescope but use others as well.
Sky tonight
https://skyandtelescope.org/interactive-sky-chart/

Jupiter's moons
https://skyandtelescope.org/wp-content/ ... piter.html

The Great Red Spot
https://skyandtelescope.org/observing/i ... -red-spot/

Saturn and its moons
https://skyandtelescope.org/wp-content/ ... aturn.html

Mars (when it comes around again)
https://skyandtelescope.org/wp-content/ ... /mars.html

And, finally, I mentioned taking an online class in astrophysics and I am looking at another. In addition to a standard university textbook and some other classroom materials that I acquired over the years, I recently bought Steven Weinberg's overview lectures.
Image
And another textbook for a one-year class.
Image

It does not matter what kind of telescope you have, or what your oculars are, or the magnification of your finderscope, or the load bearing limit of your mount and tripod. If you do not understand what you are looking at, why are you out there?
And when it comes to numismatics, make a difference between enthusiast and investors.
- 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: Upgrading your astro equipment

#16

Post by OzEclipse »


Bigzmey wrote: Wed Jul 21, 2021 11:14 pm
turboscrew wrote: Wed Jul 21, 2021 10:36 pm Agree. You buy a big fast scope, and you realize, everything is expensive.
The prices of mounts grow much faster than their load rating (and so does the weight).
For an F/6 scope or slower, you can choose between different eyepieces, but faster scopes require better corrected - and more expensive - ones. Last year there were many eyepiece series with notes like "crisp view with F/6 or higher" or "works very well with F/5 or slower". Now the se notes have disappeared, and choosing an eyepiece has become harder.
And the smaller the F-number is, the more expensive the eyepiece tends to be.

Also. get big aperture for light only. In theory you can use much bigger magnifications with bigger apertures, but in practice, the atmosphere limits the generally usable resolution to <= 300x.
Definitely something to consider. On faint galaxies it is very easy to see advantage of 9.25" SCT over 4" refractor. In theory 9.25" SCT also should provide more detailed views of planets. In practice it is often not the case. Last year the seeing was bad and on average night 4" frac has delivered similar and sometimes even better views of Jupiter and Saturn.
Hi Andrey and Turboscrew,

I have a different view to some of these statements above.

I don't know what your local conditions are like. In my experience, a large aperture always outperforms a small aperture. If the seeing is that bad, pack up or put a stop on the large aperture. However, I wonder if part of what you may be experiencing might be tube currents or lack of thermal equilibrium. SCT's are particularly susceptible to tube current problems. I don't own an SCT but I have read that wrapping the tube with insulating foam or coreflute keeps the warm air inside and prevents convection currents allowing higher magnification observing earlier in the session.

Seeing conditions in my part of the world often change a lot during the night. Frequently stable just after sunset, then unstable early evening, stabilises around midnight, excellent in the small hours.

My 18"dob has a thin 18" Galaxy optics mirror, dual primary mirror fans and a mostly open truss design with plenty of clearance in the rocker box to minimise tube currents. On any given night, it is generally thermally settled well before my friend's Takahashi 12" cassegrain has thermally equilibrated. When conditions are less than ideal, patience at the eyepiece often rewards with short periods of stability when the observer can see much more detail than through a smaller aperture. If it is a 300x "night," 300x through a large aperture will reveal much more planetary detail than 300X through a smaller aperture. My 18" gets 350x with a 7mm Nagler. It is a push to dob and I find higher magnifications harder to use due to the rapid movement of the image. On Jupiter, mars and Saturn, I think I can see as much detail at 350X with a 7mm Nagler, as i can at 500x with a 5mm Pentax XW.

It's possible that your local seeing conditions are so bad so often that your statement is correct for your local conditions, but you should not generalise that to global advice.

Turbo: Using an f4 telescope you should probably always use a good coma corrector( CC) when observing. Then your eyepiece doesn't need to be so well-corrected. A Nagler design might give you acceptable images without a CC. But with a coma corrector, if the primary optic is a well corrected parabola, both high magnification and wide field should be possible and with a wider range of eyepieces. Matt (Rainmaker) sold me his 18" f5.5 and then built himself a more transportable 18" f3.5. He has a permanently mounted CC in it and the views are better and seem even sharper without a hint of coma than my f5.5 which itself is an excellent optic. However, if your optics are good, and Orion UK have a good name, then a good CC is a worthwhile investment.

Regards

Joe
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Amateur astronomer since 1978...................Web site : http://joe-cali.com/
Scopes: ATM 18" Dob, Vixen VC200L, ATM 6"f7, Stellarvue 102ED, Saxon ED80, WO M70 ED, Orion 102 Maksutov, ST80.
Mounts: Takahashi EM-200, iOptron iEQ45, Push dobsonian with Nexus DSC, three homemade EQ's.
Eyepieces: TV Naglers 31, 17, 12, 7; Denkmeier D21 & D14; Pentax XW10, XW5, Unitron 40mm Kellner, Meade Or 25,12
Cameras : Pentax K1, K5, K01, K10D / VIDEO CAMS : TacosBD, Lihmsec.
Cam/guider/controllers: Lacerta MGEN 3, SW Synguider, Simulation Curriculum SkyFi 3+Sky safari
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Re: Upgrading your astro equipment

#17

Post by Bigzmey »


Hi Joe
If you search forums including this one for the discussions on the effects of poor seeing on large apertures you will find many observers sharing our sentiment.

I do remember one evening in 2016 when Jupiter was riding high in Leo where I had magical experience of observing Jupiter at 400x and seeing the levels of details I never forget. 5 years later I am still waiting for another night like this.

If you can see something like that on regular basis, count your blessings. It's like saying why can't you guys get Bortle 1 sky, it is so easy for me. :lol:
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: Upgrading your astro equipment

#18

Post by turboscrew »


OzEclipse wrote: Sat Jul 24, 2021 2:58 am
Bigzmey wrote: Wed Jul 21, 2021 11:14 pm
turboscrew wrote: Wed Jul 21, 2021 10:36 pm Agree. You buy a big fast scope, and you realize, everything is expensive.
The prices of mounts grow much faster than their load rating (and so does the weight).
For an F/6 scope or slower, you can choose between different eyepieces, but faster scopes require better corrected - and more expensive - ones. Last year there were many eyepiece series with notes like "crisp view with F/6 or higher" or "works very well with F/5 or slower". Now the se notes have disappeared, and choosing an eyepiece has become harder.
And the smaller the F-number is, the more expensive the eyepiece tends to be.

Also. get big aperture for light only. In theory you can use much bigger magnifications with bigger apertures, but in practice, the atmosphere limits the generally usable resolution to <= 300x.
Definitely something to consider. On faint galaxies it is very easy to see advantage of 9.25" SCT over 4" refractor. In theory 9.25" SCT also should provide more detailed views of planets. In practice it is often not the case. Last year the seeing was bad and on average night 4" frac has delivered similar and sometimes even better views of Jupiter and Saturn.
Hi Andrey and Turboscrew,

I have a different view to some of these statements above.

I don't know what your local conditions are like. In my experience, a large aperture always outperforms a small aperture. If the seeing is that bad, pack up or put a stop on the large aperture. However, I wonder if part of what you may be experiencing might be tube currents or lack of thermal equilibrium. SCT's are particularly susceptible to tube current problems. I don't own an SCT but I have read that wrapping the tube with insulating foam or coreflute keeps the warm air inside and prevents convection currents allowing higher magnification observing earlier in the session.

Seeing conditions in my part of the world often change a lot during the night. Frequently stable just after sunset, then unstable early evening, stabilises around midnight, excellent in the small hours.

My 18"dob has a thin 18" Galaxy optics mirror, dual primary mirror fans and a mostly open truss design with plenty of clearance in the rocker box to minimise tube currents. On any given night, it is generally thermally settled well before my friend's Takahashi 12" cassegrain has thermally equilibrated. When conditions are less than ideal, patience at the eyepiece often rewards with short periods of stability when the observer can see much more detail than through a smaller aperture. If it is a 300x "night," 300x through a large aperture will reveal much more planetary detail than 300X through a smaller aperture. My 18" gets 350x with a 7mm Nagler. It is a push to dob and I find higher magnifications harder to use due to the rapid movement of the image. On Jupiter, mars and Saturn, I think I can see as much detail at 350X with a 7mm Nagler, as i can at 500x with a 5mm Pentax XW.

It's possible that your local seeing conditions are so bad so often that your statement is correct for your local conditions, but you should not generalise that to global advice.

Turbo: Using an f4 telescope you should probably always use a good coma corrector( CC) when observing. Then your eyepiece doesn't need to be so well-corrected. A Nagler design might give you acceptable images without a CC. But with a coma corrector, if the primary optic is a well corrected parabola, both high magnification and wide field should be possible and with a wider range of eyepieces. Matt (Rainmaker) sold me his 18" f5.5 and then built himself a more transportable 18" f3.5. He has a permanently mounted CC in it and the views are better and seem even sharper without a hint of coma than my f5.5 which itself is an excellent optic. However, if your optics are good, and Orion UK have a good name, then a good CC is a worthwhile investment.

Regards

Joe
Well, I think seeing conditions vary from place to place, and I guess the polar vortex plays its part here.
But I think, in general, the 300x is the top at most places. In Finland it seems to be around 250x.
The main point, however, is that there is such limit everywhere.

And when it comes to coma corrector, I have this: https://explorescientificusa.com/produc ... -corrector
- 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: Upgrading your astro equipment

#19

Post by mikemarotta »


Bigzmey wrote: Fri Jul 23, 2021 11:23 pm... However, if I would buy AZGti first without settling on the scope I could miss the mark since it has only 11lb capacity.
Right. We had the same discussion about my 102-mm ED APO which you pointed out would be front-heavy and overweight for my Explore First Light mount and tripod. That is why shopping for the mount first is very much like shopping for the telescope first: What do you want it for? What kind of observing do you expect to do? Buying the lightest mount is like buying the smallest aperature because it is the cheapest. Think the problem through. In my case, just as a first approximation, I set my limit at 30 lbs (14 kg) as the most that I can lift, carry, and set comfortably. Using JayTee's Table of Mount Payloads, I can see that I can expect to pay between $800 and $1500. (Prices have gone up since that was published.) And I might get by with 27lbs (1.25kg) for a little less, but that would be near the limit of any telescope that I might want for observing and not at all for astrophotography which holds little interest for me.
---------------------------------------
Michael E. Marotta
Astro-Tech 115 mm APO Refractor Explore Scientific 102 mm f/6.47 Refractor Explore Scientific 102 mm f/9.8 Refractor Bresser 8-inch Newtonian Reflector Plössls from 40 to 6 mm Nagler Series-1 7mm. nonMeade 14 mm. Mounts: Celestron AVX, Explore Twilight I Alt-Az, Explore EXOS German Equatorial
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Re: Upgrading your astro equipment

#20

Post by mikemarotta »


OzEclipse wrote: Sat Jul 24, 2021 2:58 am In my experience, a large aperture always outperforms a small aperture.
Yes, of course, Joe, more light is better. Even in the early 18th century, there were telescopes with lenses of nominally small aperature (like 3 inches about 700 mm) but long focal lengths for high power. However, the best advances in understanding came later in the century from Herschel's very large mirrors. Aperature counts. That said, though, it is indeed focal ratio - focal length divided by aperature - that delivers value to the observation.

Waiting in the wings, I have an 8-inch 208mm Newtonian. When it is up an running, I expect broad, bright views. But as an f/3.9 F=819mm, it will not give much more magnification than my refractors: 70 mm f/10 F=700 mm; 102mm f/6.47 F=660 mm; 115 mm f/7 F=805 mm. 300X is impossible. I do not like the 6mm Ploessl that I have but if I used it with my 2X Barlow, magnification can never exceed 273. I have found from experience that the 8mm Ploessl with the2X Barlow is my practical limit: 204.75 when the 8-inch is up and 201.25 when the 115mm is mounted; but right now with the 102-mm aperature f/6.47 F=660-mm magnification = 165X.

And that's only for splitting doubles and other coarse work.

My best viewing based also on my physiology is with a 17mm and Barlow in the 102 for 77.6X
You might not want to go outside for performance so underwhelming.
And that's fine.
For you.

I could ask a lot of rhetoical (and argumentative) questions. The fact is that you can enjoy playing cricket without playing tests. We all enjoy stargazing, at whatever levels work best for us by whatever means we have for our lifestyles. It can be an aesthetic experience, which is to say: it is self-validation.

It might make an interesting project to observe and report naked-eye. I mean, Andromeda is there, the Beehive, Ptolemy's, ... I read that if you are in a very dark site, and you can put a tree or a barn between you and the disk of Jupiter, you can see its moons naked eye. Now, that would be something to report!
Last edited by mikemarotta on Sat Jul 24, 2021 5:27 pm, edited 1 time in total.
---------------------------------------
Michael E. Marotta
Astro-Tech 115 mm APO Refractor Explore Scientific 102 mm f/6.47 Refractor Explore Scientific 102 mm f/9.8 Refractor Bresser 8-inch Newtonian Reflector Plössls from 40 to 6 mm Nagler Series-1 7mm. nonMeade 14 mm. Mounts: Celestron AVX, Explore Twilight I Alt-Az, Explore EXOS German Equatorial
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