Author Topic: $250 for Accessories-Make the most of my beginner's scope  (Read 719 times)

tiogeroligh

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$250 for Accessories-Make the most of my beginner's scope
« on: December 27, 2017, 09:26:31 PM »
(TL,DR- How would you spend $250 to accessorize an entry-level 102mm f/5.9 achro refractor?)

Hello All!

Let me begin by thanking everybody here at Cloudy Nights for the wealth of information you have already provided me. As a newby astronomer, I have found this community to be invaluable. This post is going to be a little long, so I am going to cut to the chase and save some ink. I'll introduce myself more thoroughly in the introduction thread soon.
I have a Meade Infinity 102mm f/5.9 achro refractor. Not the best scope, but generally it is serving me well.
That said, it has some "quirks" that I would like to improve upon.
I am a student living on loans, so saving until I can afford a better telescope or higher quality accessories is not an option. There is no income to save.
That said, I have recently had a windfall of $250, and I wish to invest it in the telescope
Below I am going to outline some of the scope's shortcomings that are bugging me and some of my thoughts about addressing them. My hopes are that a) you will have better ideas than i do, and b) you can help me prioritize and maximize my budget. I can't do everything I want for $250.
Below are my basic gripes and ideas. Don't feel like you have to address them one-by-one. In fact, feel free to disregard all my ideas. You have $250 to spend. How would you make my telescope better?

Eyepieces
The scope comes with 1.25" MA series eyepieces in 26mm, 9mm, and 6.3mm, giving me magnification 23x, 67x, and 95x, respectively. I spend most of my time using the 26mm for "rich field" observing and the 6.3mm for the Moon, Mars, and Saturn. I haven't really figured out what the 9mm is for.

The eyepieces have generally been satisfactory, but don't reach the full useful-magnification potential of the scope (around 200x I think?). The scope comes with a 2x barlow, but I have not been able to pull good views of Saturn, Mars, or the Moon through it. The image breaks down. Perhaps it has just been observing conditions, but I suspect the barlow is junk.

I could a) buy a new Barlow or b) buy a 4mm (150x) or so eyepiece and get near my scope's magnification limit, and do so with fewer optical elements.
While I'm at it I think I might like to add a 32mm or 40mm eyepiece for even wider field viewing (recommendations?).
This also leaves me with the decision of a) blow my whole budget on a couple high quality eyepieces, or buy "budget eyepices" to leave money for other accessories. I was kind of thinking about the Gosky plossl's on Amazon.

Finder Scope
My scope came with a red dot finder. It stinks. I would like to put a magnified finder on it.
Will I be okay with a cheap 6x30, or will that also leave me wanting more after a week or two?
Do I have to mount it in place of the red dot finder, or can I mount it separately (and keep both)? I have some tools and I'm a handy guy. Is it okay to drill into the optical tube and mount the new finder directly?

Rack and Pinion Focuser (I want dual speed)
The scope comes with a 2" rack and pinion focuser with a 1.25" adapter. The focuser is actually fairly smooth, but I find myself really wishing I had dual speed focusing. I don't think a new two speed focuser is going to be within my budget.
I thought maybe I could attach a helical focuser in front of the star diagonal. I could then use the rack and pinion for gross focusing and the helical focuser for fine focus. Thoughts?

Star Diagonal (2" maybe?)
The scope comes with a 1.25" plastic (but fairly sturdy) star diagonal.
Is there any chance my high-power image breakdown described above could be due to a cheap diagonal? Could a better one help?
Also, I really enjoy my time with the 26mm eyepiece the most for its wide views. This gets me thinking about even wider views.
For around $210 I can get a 2" diagonal and a 37mm 2" super-wide w/ 70mm afov (or similar), and have $40 bucks left to play with for a high-magnification eyepiece or for a better finder. Could this be a worthwhile investment at this point?

Thanks to everybody who made it this far! As I said earlier, these are my ideas, but I'm interested in your ideas. You have $250 to spend. Go nuts!



hutualyli

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #1 on: December 28, 2017, 09:28:34 PM »
I have used a 2" to 1.25" helical focusing adapter with good results on a reflector. I would not recommend putting it in front of the diagonal or else your eyepiece orientation will be moving all over the place while you focus. You could get a 2" diagonal and put it behind the diagonal but now you can't use 2" eyepieces. So it is a less than ideal solution.

A 6x30 won't be much different than a red dot (worse really) unless you have really dark skies. Go 50mm or go red dot. For that scope I would go red dot. Spend your dough on something else. Unless you are like my friend who always forgets to turn it off and therefore goes thru a battery per stargazing session.

your Barlow is probably what is messing up your high power views. If you like your lenses well enough, just get a 3mm for high power. Maybe a Zhummel Planetary. If you really like it you can add the 6mm and 9mm to upgrade your others.

As for low power, wide field, I wouldn't go much above 30mm unless you have reasonably dark skies. So a 32mm plossl if you stay at 1.25" or a 30-32mm wide angle 2" with 2" diagonal. That will eat most of your budget right there though.

A UHC or Narrow Band nebula filter would be a nice pickup if you can afford it. But better eyepieces may be the priority for now.

Scott

unexaric

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #2 on: December 29, 2017, 05:59:20 AM »
A telescope is only half of the one, with the other half being the eyepieces, for one cannot be used without the other. Telescopes come and go, but eyepieces are like luggage, for life, and to be used with successive telescopes in future.

When choosing glasses or lenses to combine with the objective-doublet of the refractor, you want the overall quality to be more or less balanced. If, for example, one combines a poor-quality eyepiece with an otherwise quality refractor lens(or a Newtonian primary mirror), then the images are going to suffer, and with the telescope unable to reach its full potential.

But that doesn't mean having to break the bank in the quest for quality. Faster telescopes(f/4 to f/6) do tend to be a bit particular as to what is combined with their objectives(primary lenses and mirrors), but at f/6 the need to satisfy said "hunger" is not as critical.

With the Meade's 600m focal-length, a 26mm(23x) is a low-power eyepiece; the 9mm(67x) a moderate-power, and the 6.3mm(95x) a moderate-to-high power. A 3mm(200x) would be a high-power, in conjunction with a 600mm focal-length.

It's at the higher magnifications where the telescope, eyepiece and barlow have to work the hardest in order to produce good images, therefore they need to be of better quality; the glasses of better figure and polish. The dynamic, fluctuating atmosphere needs to be cooperative as well for best image quality. Also at the higher powers it becomes more difficult to track an object with a manual mount, so at the higher powers oculars with wider fields-of-view are desired.

Whilst the Meade may appear to have a drawtube to accept a 2" visual-back, bringing one or two 2" oculars to focus is a different matter entirely. Meade describes the focusser to be only a 1.25"; something to think about. You would either have to cut and shorten the tube and remount the focusser; or add long, unwieldy tube-extensions. If you feel that you can experiment, then by all means.

If I had a Meade like yours in front of me, and wished to enhance its performance...

A mirrored star-diagonal...

lhttp://agenaastro.co...ssion-ring.html ...or... http://agenaastro.co...r-diagonal.html

...or a good prism... http://agenaastro.co...r-diagonal.html

If you're bothered by the chromatic aberration, or false-colour, in a fast-achromat... http://agenaastro.co...ler-filter.html

...or, for a less-expensive alternative to reduce the false-colour...

http://agenaastro.co...low-filter.html ...and/or... http://agenaastro.co...low-filter.html

Inexpensive yet good-to-better quality barlows...

http://agenaastro.co...arlow-lens.html
http://agenaastro.co...arlow-lens.html
http://agenaastro.co...ead-ub2stl.html
http://agenaastro.co...qb-2956185.html

A barlow is mandatory with a 600mm focal-length, if wanting to realise the telescope's full potential, and it pays to get one of better quality. Many beginners do not take the quality of barlows as seriously as the eyepieces. Anything introduced into the optical train, from the objective to the eye, will affect the final image.

Oculars...

http://agenaastro.co...l-eyepiece.html (20x, and binocular-like)
http://agenaastro.co...a-eyepiece.html (30x, but only if you're looking to replace the bundled 26mm)
http://agenaastro.co...w-eyepiece.html (40x)
https://www.astronom...ece_p16946.aspx (50x)
https://www.astronom...ece_p16945.aspx (75x)

This wide-field 9mm(67x) is popular... http://agenaastro.co...a-eyepiece.html

The same ocular can be had for even less if you don't mind waiting on the boat... http://www.ebay.com/...DoAAOSwyjBW3lNh

Sames goes for the 20mm listed above... http://www.ebay.com/...0YAAOSwxp9W3kej

Here are both the 6mm and 9mm 66° wide-field oculars at a bargain... http://www.ebay.com/...VwAAOSwdzVXo~ut

There's even a 15mm... http://www.ebay.com/...KEAAOSwv9hW3kiK

...and the 15mm and 20mm together... http://www.ebay.com/...WUAAOSwHoFXqEEF

By using PayPal to pay, you risk nothing.The preceding were merely examples of what might be considered given the stated budget.

Jerome Fountain

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #3 on: December 29, 2017, 10:36:52 PM »
Read lots of forums. put that money in the freezer so it doesn't burn a hole in your pocket. Every quality piece of equipment you DO buy can be used on any future scope (for the most part). You will at some point want a RACI finder but make sure it's an 8x50. I've got a nice 8x50 RACI on my AR102, but I don't use it much (it's a wide field scope). Scott above is right about 30mm or so being a good choice for wide field. I have a 40mm and live under pretty dark skies and it's washed out a lot of the time (but I still see lots of stars). You'll definitely want a nicer diagonal (or 4), you'll definitely want different eyepieces (although I wouldn't throw THOSE away. A focuser is needed at that short focal length yes, but if you take the time to remove the glue/grease flock/blacken that focuser tube and shim it nicely with teflon it could work well. Then an addition of a larger focus wheel/knob on one side would give you a 2 spped capability. As far as recommending eyepieces the amount of eye relief you require and what kind of targets you're interested in are needed for anyone to give appropriate suggestions. Many very nice choices are out there. I'm liking waterproof stuff btw and waiting to see how the new 62* series pan out. Quick suggestions...you're going to need a mount. It's recommended you spend more on the mount/tripod than the telescope. That too can be used with many future scopes. BIG candy store out there. Me? I'm looking at that 26mm 62*, the 6.7 & 11mm 82*, and the Meade 5.5mm. Got the 16mm 68*. trying to keep it light. Sorry if I sound like an ES salesman, trust me, I wish the TV 7mm was waterproof. I may not let that stop me though. Geez, a 6, a 6.3, a 6.5, a 6.7 and a 7mm? It never ends. Do a lot of reading. GAS will get you, resistance is futile. Save up $159 more and get the Omni XLT it comes with an acceptable mount, diagonal, and eyepiece and then use both scopes (alternately) on that nice mount. That's what you should do if you like refractors. Hindsight says I should have saved a little more and bought the Omni XLT WITH cg-4 mount for $409 but I got the Twilight 1 for $200 instead as I was looking only for a mount. Super duper mount....for a short 80mm refractor. Live and learn. The Twilight 1 is an awesome and beautiful mount, I love mine, but it's not enough to keep an AR102 steady at high mag (which it's not designed for anyway). Good cheap eyepieces? 6 & 9mm expanse clones. Any AT Paradigm ED's (especially8-15) ,The 6.5mm Meade HD, maybe the 9mm. the Meade 5.5mm UWA. All the ES eyepieces are great values. Used eyepieces can be the best value. Good luck Sky Muse just hit it out of the park btw

guisamcipen

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #4 on: December 30, 2017, 07:16:14 AM »
Some really really great suggestions above.
The best one being put the cash in the freezer.

Do you have this scope package?
http://www.meade.com...-refractor.html

#1 . The item that I use the most that you don't have is a 32mm plossl.
This will give you the widest field of view possible with your 1.25 inch focuser.
Besides using it to take in a bunch of sky, I use it all the time as a "finder" eyepiece.
You will have a 2.75 degree field of view, and you may find that you will not need
a new finder to get things into view. I have a high point omni plossl. You should be able to get one for around $30.00 on this site.

Additionally if you have never seen or hefted 2" diagonals an occulars they are huge and heavy. Your mount may not be strong enough to hold these things.#2 Beef up ths mount. If you are using this scope on a hard surface, like a deck, or driveway, you might want to get some anti-vibration pads. I think this mount would be wobbly for high powers.
I have seen plans to make your own for a few dollars
with furniture glides from home depot.  Anything that you can do to stiffen up the mount will be good. There are suggestions here like adding great stuff to hollow legs. Browse the ATM section.

#3 If the star diagonal is the erecting that may be causing your high power viewing issues.
Get a non erecting prism diagonal. Mirrors I think??? are better, but usually you have
to go up in price to get a mirror that is better than a low cost prism.

#4 If your high power viewing does not improve after replacing the diagonal, get one of the
barlow's thas skymuse says.

200 power is tough to obtain with a 100mm scope. I have a celestron GT 102 f/10.
Most nights are 160 if Im looking at planets, doubles etc.. I need good skies where 200 adds more quality to what I see.

As skymuse says if you don't like CA on your bright objects get a #8 color filter
It does 80% of what a minus-v filter does at 1/4 the price.

Aaron Maggot

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #5 on: December 31, 2017, 01:50:05 AM »
The AR102 is heavy! A twilight I should be sufficient for the Meade refractor. Unfortunately it would eat up 80% of his budget, but it would be a nice upgrade.

unoutdethea

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #6 on: December 31, 2017, 06:12:41 AM »
The facts concerning your telescope are that it is a short-focus doublet and as such is not really designed to perform very well at magnifications much above 100x-125x. Its performance is much better on wide-field views, or most magnification on the Moon. Neither is it a high-end instrument worth investing a lot in for accessories.

For locating most objects a simple red dot finder should be ok when working a low power. If you want more, than a red dot finderin combination with an 8x50 RACI finder will suit your needs.

Given the optical specs of the scope, while it's nice, a better diagonal, Barlow, or minimal focal-length eyepiece (3mm-6mm) are not likely to improve matters and more probably will just disappoint. Wide-field views are where this little scope should excel, so a nice wide-field (68* or 82* AFV) providing about 20x-25x should prove advantageous providing that you have at least moderately dark skies.

BrooksObs

housletica

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #7 on: December 31, 2017, 07:02:09 PM »
Get a Rigel QuikFinder, 2" diagonal, and a 37mm 70° eyepiece. You'll get a true field of view of over 4° with that EP and the Rigel is plenty useful for both locating planets and DSOs.

Corey Howell

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #8 on: January 01, 2018, 09:23:23 AM »
You will eventually get a better scope, I would put my money into quality eyepieces that you will carry forward. Spending cash on anything less than a good quality and reusable item is just not efficient.

Matt Gibson

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #9 on: January 08, 2018, 02:44:20 PM »
Cogley,
Welcome to cloudy nights!

I had the Meade infinity 102. The issues are the mount and the diagonal for mid to high power. The mount has too much backlash to acquire and keep targets. It's ok for the moon but annoying for anything else.

To address that problem I put the scope on a different mount. A SkyWatcher AZ4 mount, which is not sold anymore, but Orion still sells it as the Versago II mount for $179. This mount can handle 15lb

For the diagonal you can go two ways. 1.25" or a 2" diagonal. I did use both. And yes the focuser can handle a 2" diagonal with lighter 2" eyepieces, say 12 oz max. The issue I had with the focuser was not the glue that was used, which by the is better than the Celestron (Synta) glue, the issue is lack of fine focus, especially at high powers. If you do go down the 2" road you will need to buy rings and a dovetail because the weight balance will have shifted to the back. An upgraded 2" dual speed focuser would address this, but not sure it is worth it for this scope.

Ok lets talk eyepieces. The ones included are just ok. For wider fields the Celestron Omni 32mm sold on Amazon is very good. For higher power I liked the Celestron X-Cel 60 degree 5mm eyepiece. Amazon usually has the lowest price on this eyepiece line, which I recommend as the next step up from plossls. As for the barlow that came with the scope it is junk and needs to be replaced
I eventually sold this scope last year when Explore Scientific had the ES AR102 on sale for $299

behelphyri

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #10 on: January 09, 2018, 07:05:22 AM »
Quote
(TL,DR- How would you spend $250 to accessorize an entry-level 102mm f/5.9 achro refractor?)

Hello All!

Let me begin by thanking everybody here at Cloudy Nights for the wealth of information you have already provided me. As a newby astronomer, I have found this community to be invaluable. This post is going to be a little long, so I am going to cut to the chase and save some ink. I'll introduce myself more thoroughly in the introduction thread soon.
I have a Meade Infinity 102mm f/5.9 achro refractor. Not the best scope, but generally it is serving me well.
That said, it has some "quirks" that I would like to improve upon.
I am a student living on loans, so saving until I can afford a better telescope or higher quality accessories is not an option. There is no income to save.
That said, I have recently had a windfall of $250, and I wish to invest it in the telescope
Below I am going to outline some of the scope's shortcomings that are bugging me and some of my thoughts about addressing them. My hopes are that a) you will have better ideas than i do, and b) you can help me prioritize and maximize my budget. I can't do everything I want for $250.
Below are my basic gripes and ideas. Don't feel like you have to address them one-by-one. In fact, feel free to disregard all my ideas. You have $250 to spend. How would you make my telescope better?

Eyepieces
The scope comes with 1.25" MA series eyepieces in 26mm, 9mm, and 6.3mm, giving me magnification 23x, 67x, and 95x, respectively. I spend most of my time using the 26mm for "rich field" observing and the 6.3mm for the Moon, Mars, and Saturn. I haven't really figured out what the 9mm is for.

The eyepieces have generally been satisfactory, but don't reach the full useful-magnification potential of the scope (around 200x I think?). The scope comes with a 2x barlow, but I have not been able to pull good views of Saturn, Mars, or the Moon through it. The image breaks down. Perhaps it has just been observing conditions, but I suspect the barlow is junk.

I could a) buy a new Barlow or b) buy a 4mm (150x) or so eyepiece and get near my scope's magnification limit, and do so with fewer optical elements.
While I'm at it I think I might like to add a 32mm or 40mm eyepiece for even wider field viewing (recommendations?).
This also leaves me with the decision of a) blow my whole budget on a couple high quality eyepieces, or buy "budget eyepices" to leave money for other accessories. I was kind of thinking about the Gosky plossl's on Amazon.

Finder Scope
My scope came with a red dot finder. It stinks. I would like to put a magnified finder on it.
Will I be okay with a cheap 6x30, or will that also leave me wanting more after a week or two?
Do I have to mount it in place of the red dot finder, or can I mount it separately (and keep both)? I have some tools and I'm a handy guy. Is it okay to drill into the optical tube and mount the new finder directly?

Rack and Pinion Focuser (I want dual speed)
The scope comes with a 2" rack and pinion focuser with a 1.25" adapter. The focuser is actually fairly smooth, but I find myself really wishing I had dual speed focusing. I don't think a new two speed focuser is going to be within my budget.
I thought maybe I could attach a helical focuser in front of the star diagonal. I could then use the rack and pinion for gross focusing and the helical focuser for fine focus. Thoughts?

Star Diagonal (2" maybe?)
The scope comes with a 1.25" plastic (but fairly sturdy) star diagonal.
Is there any chance my high-power image breakdown described above could be due to a cheap diagonal? Could a better one help?
Also, I really enjoy my time with the 26mm eyepiece the most for its wide views. This gets me thinking about even wider views.
For around $210 I can get a 2" diagonal and a 37mm 2" super-wide w/ 70mm afov (or similar), and have $40 bucks left to play with for a high-magnification eyepiece or for a better finder. Could this be a worthwhile investment at this point?

Thanks to everybody who made it this far! As I said earlier, these are my ideas, but I'm interested in your ideas. You have $250 to spend. Go nuts!

If must buy new, I'd get a Versago mount for $179 ,one of the Chinese eBay 62 degree aspheric 4mm eyepiece for $10(or the setof 4,10,and 23mm for $23.  The Versago can be used with many different telescopesof modest weight and the stability and movement is much better than the usual beginner azel. At least get the 4mm ;at $10 or less it is less than one pizza.

For actually STUDYING the planets or anything ,a motorized scope that follows the sky is practically mandatory.Hand cranking usually means induced vibration of the image.A simple RA motor will suffice on a stable EQ mount.

Over your budget but nice to have: For finer focusing the Accufocus unit from Orion made a HUGE difference in achieving a correct focus with an otherwise stock Celestron ST-80.By removing your hand from the focuser and substituting a motor scope vibration is reduced to nearly none.All these thing can be used with other or better scopes you will acquire.

Put the $250 aside and watch craigslist,etci n your area ,CN classifieds, Amazon, and ebay;continue to read online about any scope or accessories you think interesting.Often you can save half IF the secondhand scope has been well cared for or stored AND you know what to look for.

Paul Syring

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #11 on: January 09, 2018, 08:38:03 AM »
I upgraded my cheap plastic star diagonal to a $31 metal GSO star diagonal and it was a big improvement. I'd also suggest a 6mm eyepiece with more eye relief like an Expanse clone, like an Agenda EWA for $45. Then,maybe upgrade the MA25 eyepiece to a 25mm Plossl for $30. But that's only $106. Sorry, you'll still have $144 leftover if you do that.

trafefupgi

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #12 on: January 11, 2018, 03:55:04 AM »
Too Long, Didn't Read Version of my Post:

My general plan at this point:
Invest in one mid-quality ($50 range) short focal length eyepiece that will give me 125x-150x. Zhummel Planetary Z-series has been suggested.
Invest in one or two low-to-mid-power, wide field EP's. ($100-$150 dollars combined).
Buy this star diagonal for better viewing and the built in helical focuser. ($70)http://www.williamop...&product_id=676
Maybe skip a meal and splurge on a #8 color filter. ($13)
Depending on results of the above, maybe try to score a better mount as a Christmas present.
My actual post-

Thank you all for taking time to read my lengthy post and thank you for the very detailed replies so far. I know just enough to know that "I don't know what I don't know," and that just a little bit of knowledge can get you into more trouble than none. It is nice to have the wisdom of others to lean on so that I can avoid at least the most severe mistakes in the expenditure of my funds.

Perhaps I should have included more detail in my original post, but I felt bad about its length and didn't want to discourage readers.

I live at the edge of yellow zone sky, with unlimited access to green zone at a friend's house ten minutes away, and dark-blue-to-grey zone sky inside an hour drive. It really makes me wish I had a better scope.

Unfortunately, I am currently in a graduate program that prevents me from working, with two years of school left. So I am stuck with the scope I have and the budget I have for two more years. I truly appreciate the advice to put the money in the freezer and to save it to upgrade a future, better telescope, however...

...I am currently blessed with the darkest sky I am ever likely to have regular access to, and I want to make the most of it. That means pushing this (unfortunately limited) scope to the best use I can make of it. I would rather spend "inefficiently" right now on this telescope and have the best two years I can, than save the coin to go towards a better scope when I return to the white zone after I graduate and get a job. The next two years aren't going to be perfect, but I am blessed with phenomenal local observing conditions, and I wish to do what I can to make the most of them.

That said, I intend to seriously consider all the advice here. I have some follow up questions, if you would indulge me.

My General Plan
I have tried to condense the advise above to a few key principles, as I lack the expertise to judge the merit of one person's advice over another when they differ. I welcome continued arguments on the merits of different approaches, to the extent you guys wish to spend your valuable time here with me.

My take-aways are:
I should limit my expectations for high-power viewing, and accept a maximum magnification in the 100x-150x range.
This scope excels at low power, wide-field viewing, and I would be wise to spend my money in this arena.
No finder in my budget range will provide an efficient investment over the red-dot.
A better star diagonal would help. Stick to 1.25".
My mount/tripod are going to limit my performance.
My general plan at this point:
Invest in one mid-quality ($50 range) short focal length eyepiece that will give me 125x-150x, unless there is a strong reason a quality barlow paired with my existing eyepieces would be better. Zhummel Planetary Z-series has been suggested.
Invest in one or two low-to-mid-power, wide field EP's (lots have been suggested here and I welcome further discussion). ($100-$150 dollars combined).
Buy this star diagonal for better viewing and the built in helical focuser. ($70) http://www.williamop...product_id=676
Maybe skip a meal and splurge on a #8 color filter. ($13)
Depending on results of the above, maybe try to score a better mount as a Christmas present.

Hi Power Viewing Specific Questions

It seems like the consensus is that my useful limit will be somewhere in the 100x-150x range.
Given the optical design of this telescope, is there a reason to prefer a barlow over a 4mm or 5mm eyepiece? It seems to me that a single optical element would be preferable to putting more glass in the optical chain. I understand that a barlow "doubles" my eyepiece collection, but it doesn't really seem like this scope offers the flexibility that would benefit from an extensive eyepiece collection anyways. Adding one more high power and one or two more low power eyepiece will give me 5-6 EPs. Isn't that sufficient given the limitations of this telescope?
Does any of this conversation change if I use an aperture mask to create a 60mm f/10 or 80mm f/7.5 (or something in between)?
Finder Questions
I'm gonna stick with the red-dot finder instead of wasting my money on this nit-pick. However, I've been thinking about it, and my biggest beef with the finder is actually its location. With it at the back of the scope (where admittedly all refractors put it), the large 102mm tube blocks half my view of the sky when i get down below the finder and I can't see where I'm trying to drive the scope. Is there a reason other than tradition for the finder's location here?

I've got a little bit of mad-scientist in me and I can't help but tweaking and modding my toys. Is there a reason I can't drill the front of the tube and mount the finder up front (like on a reflector)?

With these plans articulated, I appreciate your further comments and advice.

Thanks!

meenchinobun

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #13 on: January 11, 2018, 05:51:51 AM »
Hi Cogley - welcome to CN

Perhaps I'm odd, but I seldom use any of my scopes at much more than 100x. My most commonly used eyepieces provide 27x.

My take - having been through the grad school mill (twice) - keep your head down, blitz your course and limit your time under the stars until your studies are done. Every hour spent behind your books will matter. $250 could buy you a critical reference or five.

You probably won't do this, so here's my take on your shopping list... in rough order of priority.

1. You can access dark skies but you can't observe things if you can't find them. A Telrad will be big for your scope but (with the exception of high end raci's) I think it's the best finder on the market. I haven't tried a Rigel but I have tried several alternatives that would go for more than your entire budget.

2. Dealing with chromatic aberration is important - unless you're in an area where your scotopic vision dominates it will degrade image contrast. I'd say the #3 or #8 would work. #3 in dark skies and #8 on bright objects when your photopic vision will switch on.

3. It's important that your mount does not vibrate. Twist the top of the mount and try to see whether the tripod or the head are deforming more. If the legs are the problem, it's easy to cut new ones from timber and create a really stiff tripod.

4. Diagonal - this matters IF (and only if) your current one has a major problem. You can of course determine whether your diagonal is working well by comparing it with a known-good diagonal of any size. Don't worry about 2" diagonals - they are nice to have but only matter if you have 2" eyepieces. I advise you to ignore 2" eyepieces until you're earning a living...

5. Eyepieces - Your MA eyepieces are quite rudimentary. 25 & 18 mm Plossls would be nice and maybe a Barlow giving you effectively 25/18/12.5/9 for exit pupils of 4.3/3.0/2.2/1.5 mm . This is about as good as it gets. If you can get a wide angle 18 mm (more or less) then you might want to substitute a wide angle 13 mm for the Barlow and 25 mm.

If you wear glasses to correct astigmatism, you will probably want lo look for wide angle eyepieces with longer eye relief. This is less of an issue when you use higher magnifications.

6. Fine focus - I'm not convinced this will help you much. It's the sort of thing than an experienced eye can judge in a second but it would take pages to describe. If there's a local ATM group, you might want to get to know them and see what they think. They could also help you with parts to build a ~25 mm symmetric eyepiece (which is really quite easy).

leypelepha

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Re: $250 for Accessories-Make the most of my beginner's scope
« Reply #14 on: January 11, 2018, 02:10:37 PM »
I think your current plan is a good one. F6 is slightly demanding, so you are looking at $50-60 for a good 50-60 deg eyepiece, or closer to $100 for a good 70-80 deg eyepiece. The zhummel or paradigm series would work nicely (I think they are the same). The Celestron Xcel series gets some love too, although I think its appeal is more with eyeglass wearers who need the long eye relief. For the 70-80 deg think explore scientific or Meade series 5000. Celestron has some competitive ones too, ultima or axiom, whatever the line is called these days. There are cheaper 80 deg eyepieces, but those should probably be avoided with an F6 scope.

As for a mount for Christmas, the Versago or Twilight I would be nice. Vixen Portamount good too but more expensive unless you find a good sale.