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Help for choosing my first telescope ;)


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Good to hear that you have a positive opinion about the scope. Now the power tank , I won’t buy immediately with the scope , but when I actually run the scope with batteries and see if it does the trick for me or not.

Also good to know that it is portable ;) That’s good !

And about the Field Derotator - of course I will buy it - I can’t afford to buy the Sky Watcher Explorer 150P with GoTo mount for 730$  , but i can afford to buy a FREAKING FIELD DEROTATOR for 995$ plus a scope ;) (Sry , didn’t wanna sound rude xD) , but thanks anyway for letting me know there is such an accessory.

Also , knowing my location , you would understand how much shipping it will need. Does anyone have experience with long distance scope shipping ? Won’t it suffer (mainly the mirrors) from so much handling and shipping ? (Also given that the primary is not collimateable makes me worry a bit )

By the way I have another general concern about using scopes - here in Armenia the climate is quite not forgiving ;) Although we have very dry air throughout the year , we tend to have severe cold winters AND severe hot summers. This summer the temperature went up to +50 degrees Celcius (in the sun) and more than +40 almost constant in the shade (Although obviously the night temp will be lowe , but not much) . Then we have very very snowy and cold (I mean freezing , cutting cold) winters , when the temperature drops to about -15 deg. Celcius . Although last winter we had temperatures about -22 deg. Celcius. Now I would like to know what are the optimal operating temperatues for telescopes ? When is it dangerous to even expose the scope to the weather ? Or maybe temperature doesn’t affect the scope at all?

THANKS !

 

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2 hours ago, Androri said:

And about the Field Derotator - of course I will buy it - I can’t afford to buy the Sky Watcher Explorer 150P with GoTo mount for 730$  , but i can afford to buy a FREAKING FIELD DEROTATOR for 995$ plus a scope ;) (Sry , didn’t wanna sound rude xD) , but thanks anyway for letting me know there is such an accessory.

That's why I prefaced it with "Technically".  Practically is a whole 'nother matter.  It would be rather absurd to put that accessory on that scope.  Some people handy with stepper motors and controllers and machining have spun their own versions.

2 hours ago, Androri said:

By the way I have another general concern about using scopes - here in Armenia the climate is quite not forgiving ;) Although we have very dry air throughout the year , we tend to have severe cold winters AND severe hot summers. This summer the temperature went up to +50 degrees Celcius (in the sun) and more than +40 almost constant in the shade (Although obviously the night temp will be lowe , but not much) . Then we have very very snowy and cold (I mean freezing , cutting cold) winters , when the temperature drops to about -15 deg. Celcius . Although last winter we had temperatures about -22 deg. Celcius. Now I would like to know what are the optimal operating temperatues for telescopes ? When is it dangerous to even expose the scope to the weather ? Or maybe temperature doesn’t affect the scope at all?

This same concern came up recently in another thread from a Canadian.  My concerns would be the same here.  LCDs don't do well below a certain temperature, some electronics as well.  Batteries certainly don't like super cold temps, either.  Lubricants in the mount could turn to sludge as well.  The optics and mechanicals should be just fine at any temperature as long as everything has had time to acclimate to the ambient temperature.  Storing the tube in an unheated space can help speed things up.  Just don't bring cold items into a warm humid house unless they're sealed against moisture or they'll immediately get covered in condensation which could leave spots as it dries.  Don't get too close to eyepieces in the winter or the eye lens will fog over from all the moisture coming off your body.  Eyeglasses make a nice vapor barrier if you have long eye relief eyepieces.

As far as high tempertures, there shouldn't be any issues as long as it's dry.  Lubricants in the mount might dry out over time, so pay attention to any changes in the sound of the mount during rapid slewing.  We have high temperatures and high humidity here in Texas which leads to dew issues and mosquitoes.  Count your blessings it's dry where you live.

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I generally hate really cold too (LOL) , but now if I can remember accurately -when it starts snowing here , it doesn’t even stop for 2 months ... , so I guess worrying much about too cold isn’t a big concern.

And I am happy to hear that dry heat won’t interfere . Although I can say that we sometimes have that “Sahara Desert” air , which tends to make the air very turbulent (idk if it is the right term tho) , so you can see the air rise , squiggle around with just your eyes ;) Won’t that be a problem when you change from 1x-150x magnification ? :) Although it may* not be the same for the night idk.

I am also getting concerned about the battery thing , although also if I won’t use it much during the very cold , then maybe it’s ok.I am glad that ,at least, no optics will be harmed from the cold / hot . What about the power tank ? Will it run the scope normally when it’s cold ?

Also , can I use this scope without the need of electricity ? Can I just manually move it from thing to thing ? Or it will damage the system ?

You mentioned , that after condensation evaporates , there may be some dust on the mirrors . If this happens (or even not) how do you clean the mirrors ? Or is it too risky to try to do it yourself ? What about cleaning the eyepieces / barlows ?

Thanks !

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2 hours ago, Androri said:

 how do you clean the mirrors ? Or is it too risky to try to do it yourself ? What about cleaning the eyepieces / barlows ?

Thanks !

Mirrors? Very carefully!!

Eyepieces? You don't! End!

Fraid I can't help you with the rest of it but yes this scope can be used in full manual mode.

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Oh that’s fortunate ! Thanks for letting me know .

By the way what is the major difference between the reflectors and refractors ? Cause today I found an option similar to the Star Discovery 150mm reflector , instead it is a refractor.

https://www.firstlightoptics.com/startravel/skywatcher-startravel-102-synscan-az-goto.html

Now , it is a bit cheaper than the prev. one , and I would like to know more about what I would get more and what less with this one than the reflector.

The things I noiced were that :

1.Obviously cheaper.

2.Refractor means smaller in size (I assume) , easier to transport.

3.Comes with 2 eyepieces (10+20) and 2x barlow , though , with this model I lose 1 magnification because 10x2 barlow=20

4.No possible collimation problems (although they guarantee that the Star Discovery reflector is collimated for life)

5.The focal length is smaller , thus , I get less magnification for the given eyepiece ( The first major concern)

6. Lower max. magnification . (The sencond major concern)

So yea , basically the other is the same - the mount the alt az system , has the same amount of objects in the database etc.

What do you have to say about this ? Is it too low power for the planets ? Is it better/worse for DSO ? 

THANKS !

 

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Mounts are not the same. That mount does not have freedom find (it is not designed t be used with no power). 

The ST102 will show chromatic aberration on bright objects like planets, some people are more bothered by CA then others.

I would suggest you read reviews on both telescopes to get a feeling for them.

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3 hours ago, Androri said:

how do you clean the mirrors ? Or is it too risky to try to do it yourself ? What about cleaning the eyepieces / barlows ?

Mirrors should only be cleaned very occasionally. Consider that there is quite a large secondary mirror blocking the light path and you can't see that so a bit of dust on the mirror actually won't make that much difference. In addition, mirror coatings take time to harden so I suggest you give it at least a year before considering cleaning a new mirror, unless you get something particularly nasty that will eat into the coatings on it. The time between cleaning mirrors should usually be measured in years. Professional telescope mirrors are usually never cleaned until enough time has passed for the mirror to require not only cleaning, but recoating. If/when you do need to clean a mirror, this video will show you how.

Cleaning the exterior lens surfaces of an eyepiece can be done more regularly, but still try to avoid excessive cleaning so that you do not damage the coatings. The eye lens is the one most likely to need cleaning, being more exposed to dust and dirt in the following manner. Most of the time only step 1 should be required.

  1. Use a bulb blower to blow any loose dust/dirt off the lens. Try to get a bulb blower with a soft tip so that if the tip accidentally touches the lens it will not damage it.
  2. If necessary use a soft lens cleaning brush to loosen more stubborn particles. After using the brush reuse the blower.
  3. If there are water marks on the lens and all solid particles are removed, lightly spray some lens cleaning solution (e.g. Baader Wonder Fluid) onto a lens cleaning cloth (never the lens) and carefully wipe the lens. Use the solution sparingly as you do not want excess cleaning solution to seep down around the edge of the lens into the eyepiece. Clean off any remaining solution with a dry cleaning cloth. Use the blower again to remove any particles that may have come off of the cloth.

In addition, you can get a "lens pen", which consists of a brush one end and a polishing tip on the other. This can be used in conjunction with a bulb blower to clean eyepieces.

7 minutes ago, Androri said:

what is the major difference between the reflectors and refractors ?

A refractor uses lenses at the front to focus the light, a reflector uses mirrors. The refractor you are looking at is an achromatic refractor, which means that it focuses 2 colours of light at the same point, while a more expensive apochromatic refractor will focus 3 colours. This means that it will suffer from chromatic aberration (i.e. a purple fringe around bright objects). This effect will be quite pronounced in a short f5 scope, probably making it unsuitable for planetary observation. 

15 minutes ago, Androri said:

So yea , basically the other is the same - the mount the alt az system , has the same amount of objects in the database etc.

The Star Discovery mount is a newer and better mount than the synscan az.

16 minutes ago, Androri said:

Is it too low power for the planets ? Is it better/worse for DSO ? 

The optimum magnification will be lower on all objects due to having a smaller aperture. As mentioned above it is also not intended for planetary observations. The smaller aperture also means less light is gathered and so it will also be worse on DSOs than the 150p.

However, a smaller telescope that is more transportable will be much more useful when you decide that you want to try observing from a darker location.

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Oh man , you guys always fascinate me with such detailed and informative comments ! I am the buyer , yet I didn’t notice there were two different mounts on them , not to mention that one of them is not meant to work with no power.

You basically gave me the answer . I will still go with the reflector. 

As for transportation , it will probably be like once a week or sth if I am lucky ;) , and it is a place where I definately won’t walk to in any case , no matter which scope ;) xD , so as long as it is in the car it’s basically the same to take either of them along.

By the way how do you transport your scopes ? (If you even do) How to keep it safe during the process ? I guess I don’t have to worry much about collimation getting bad for the chosen model , but anyway do you collimate your scopes every time after transportation ?

And thx for the detailed guide on how to clean the stuff , I am happy it doesn’t need to be cleaned much xD LoL . I have had a microscope for years , have cleaned it once I think , and just the outside xDDD.

By the way I just remembered something , saying microscope. I think I have read somewhere (don’t remember where though) that microscope oculars do just fine with telescopes LOL. Dunno if this is true or not , but if you have any experience , tell me .Not that I plan on relying on my microscope oculars (cause they’re pretty old and some are scrached) , but it would be really intersting if it worked xD . And I have quite a few pairs , would like to know what is the correspondance between microscope and telescope oculars ( I have 5x 7x 10x 15x and 20x eyepieces ) .

:excl:PERSONAL INFO DOWN THIS POINT NO NEED TO READ IF INTEREST IS ONLY IN THE FORUM SUBJECT.:excl:

I actually bought this microscope secondhand (or maybe third or fourth LOL it is really old) from a local dealer, which is actually really powerful and fully functional . It was after I got interested in microbiology. After some while of observing I felt like I HAD TO take images and record videos of what I saw . So I started doing so from then on and now am happy with the collection of potos / videos I have and am still doing it.Some of the shots are of really interesting organisms, parts of their life cycle , which never happened to be seen since then.

By the way I DIY-ed some things to hold my simple camera in front of the eypiece , so nothing fancy , but great results.

Now all this , to tell you why I am looking for something that you can actually do some astrophitography with from the start , It’s not that I wanna sell the pictues or get HD pictues or something. I purely know myself and know for sure that the time will come , and WILL WANT TO take pictures. And plus something , which is abscent in micoscopy , there are many many objects (mainly DSO-s) which just don’t show much detail with the naked eye - so the way to actually see them you NEED TO take pictures and stack them :) .

THANKS !

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Have you thought about just getting a mount like the eq5 and using your camera and even that bresser telescope you still have. Buying bits in stages but getting a better system. Not sure if your imaging desire might over take your considered mounts capability.

Your microscope eyepieces may be wrong size not 1.25 but you might find an adaptor.

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Microscope eyepiece barrels are either 23mm or 30mm, neither of which is 1.25".  You'll need a hard to find adapter for the 23mm versions or a few wraps of electrical tape around the 30mm barrels to make them work.  Another problem is microscope eyepieces are designed to work well in slow light cones.  I think somewhere around f/15, IIRC.  Most reflectors are around f/5 to f/6, so they are much more demanding on eyepieces.  Microscope eyepieces will typically show more edge aberrations than dedicated astro eyepieces when used in a telescope.  There are exceptions like some high-end Zeiss microscope eyepieces that do very well in telescopes.

All batteries will provide less power in cold weather.  Some are more sensitive to it than others.  It has to do with the chemical reactions involved.  There will be some power, just less than you're used to during warm weather.  Anyone who's ever tried to start a car at -20 degrees Farenheit or colder knows what I'm talking about.

If you're getting Saharan winds, be careful they're not full of dust that could settle on your mirrors, and later scratch them if you're not careful blowing it off.  We get a fair amount of Saharan dust here in Texas each year.  The skies turn kind of yellowish for a week or two until a front comes through to push it south and eastward.

High winds at any altitude will affect your seeing conditions.  You can sort of judge it before setup by noting how steady the bright stars appear to be.  If they're rapidly twinkling, planet viewing will be bad.  If they're rock steady, get out there quick and observe before conditions change.

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Oh , thanks for the comments , although I guess you got me wrong about the desert air xD It’s not actually air that comes from Sahara , nor it is dusty , it is just very very hot you know. Like when you turn on a gas stove and look to the air just higher from the flame - it wobbles around from the heat - that’s the effect here during a summer day although without any fire xD.

And also :

6 hours ago, happy-kat said:

Have you thought about just getting a mount like the eq5 and using your camera and even that bresser telescope you still have.

Yes I have , but maybe not , cause photography while being very interesting subect and fun thing to do , is still not my primary reason of getting a scope ;) . Thx for advice , though don’t know what you meant by “that bresser telescope you still have” , I own / have owned no scope xD . Maybe I didn’t get what you said ^^. 

About the winds - we do tend to have quite steady winds in the evenings and midnights . Though right now looking at Vega from my window XD I can’t see any twinkling xD .

MY LONELY VEGA :icon_biggrin: !!!

Also just today I found out about another scope , I am still not sure which exact type it is tho. It seems a bit better than the star discovery series, but it is bigger too.

I had a conversation with the sellers and they told me that they would* in fact lower the price a bit for me, but the only comcern was that they did not guarantee shipping and safe handling. IDK why ?! Although there might be some comparibility issues. They sent me some really good looking photos taken directly from the scope which I put here , so yea. They say light pollution has almost no effect on the observing quality.

Plus it is in the CLEARANCE section , so I guess it is lower price than it is acrually worth .

Some of the comments on the product say that the instrutions are in Chinese , and that it is a piece of rubbish ... idk...

So basically what do you think about this scope ? Is it even worth the buck ? Here’s the link , please check and tell me :

https://www.firstlightoptics.com/clearance/hubble-cassegrain-reflector-telescope.html

THANKS !!!

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On the microscope eyepieces, yes they can work as telescope eyepieces. It all depends ...  The 23mm eyepieces are the wrong size, but 30mm eyepieces will fit with a bit of packing. Some microscope eyepieces are Huygenian and will not work well with modern short-focus telescopes and they have a narrow field of view.  Those marked as 'wide-field' are more like a Plossl eyepiece and can work well in a modern short focal length reflector.

Then there is the question of working out the focal length of a microscope eyepiece marked with x6, x10 etc. As a guide, a x10 is about 22mm focal length.

As it happens, I have a 30mm size microscope eyepiece marked WF 10x/22 and it works well in my f5 Newtonian, in fact better than my 25mm supplied-with-kit eyepieces.

I also have the 102mm Startravel you were asking about. It is a low-cost widefield scope, has noticeable chromatic aberration and is no substitute for a 6" reflector. Not recommended if you want a general purpose scope. The GoTo mount is a popular one, but the mount is designed to be portable rather than solid and it will not work for anything without a battery.

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23 hours ago, Androri said:

By the way how do you transport your scopes ? (If you even do) How to keep it safe during the process ? I guess I don’t have to worry much about collimation getting bad for the chosen model , but anyway do you collimate your scopes every time after transportation ?

For some scopes it is possible to get either a case or padded bag to make transportation easier/safer but these are usually quite expensive and for large scopes probably not that practical either. My OTA was packaged with a large foam block at either end with a circular cut out the same diameter as the tube. I kept these blocks and cut each one in half to create a pair of cradles (one for each end) that I can easily lay the OTA in to stabilise it during transport. In addition, both OTA and mount are securely strapped to fixing points to prevent movement. 

As for collimation, I almost always check it at the start of each session, even when it has only travelled a few yards from the shed to the middle of the garden. Once you know what you are doing it is not a particularly difficult or time consuming task and if you go to the effort of travelling to a dark site you don't want the night's viewing degraded by a miscollimated scope. 

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Oh great ! Thanks for the info ! 

Well if the star dicovery 150mm reflector is not well collimated , i guess , it is not well collimated for life ... The primary as they say is not collimateable and is fixed into position permanently. Maybe I got that part wrong ? Idk. But I think I got it right ;)

And wow , I didn’t know there were special microscope to telescope adapters on the market , but it seems there are :) That’s good if I won’t be able to DIY something xD I will at least (worst case) just hold my microscope eyeiece just the correct place by hand and look through it , cause I don’t wanna buu adapters just to find out that my eyepieces are dim , have unuseably narrow fov etc. LOL .

But thanks for letting me know !

By the way I have heard there are some popular books about astronomy . What would you suggest me to get and read to better understand stuff ? (Scientists themselves don’t actually understand stuff about the space tho LOOL ) 

I would like to have a book that would be more of a detailed “guide” type of thing xD . It would be anything from teaching the sky, the stars or dsos or even how to properly use telescopes and take shots of the sky ^^ .Not stories about astronomy or astro pictures :) . A book that will help me learn . 

THANKS !

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'Turn Left at Orion' is a popular book to get going with, walks you through the year (Northern hemisphere) what is visible and what expect it to look like in different sized telescopes even binoculars and how to find it manually.

Have you identified an astro club in your area/town?

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6 hours ago, Androri said:

Oh great ! Thanks for the info ! 

Well if the star dicovery 150mm reflector is not well collimated , i guess , it is not well collimated for life ... The primary as they say is not collimateable and is fixed into position permanently. Maybe I got that part wrong ? Idk. But I think I got it right ;)

And wow , I didn’t know there were special microscope to telescope adapters on the market , but it seems there are :) That’s good if I won’t be able to DIY something xD I will at least (worst case) just hold my microscope eyeiece just the correct place by hand and look through it , cause I don’t wanna buu adapters just to find out that my eyepieces are dim , have unuseably narrow fov etc. LOL .

But thanks for letting me know !

By the way I have heard there are some popular books about astronomy . What would you suggest me to get and read to better understand stuff ? (Scientists themselves don’t actually understand stuff about the space tho LOOL ) 

I would like to have a book that would be more of a detailed “guide” type of thing xD . It would be anything from teaching the sky, the stars or dsos or even how to properly use telescopes and take shots of the sky ^^ .Not stories about astronomy or astro pictures :) . A book that will help me learn . 

THANKS !

What's kind of fun with a too small barrel eyepiece when you hold it over the focuser opening is the move it left/right and up/down to examine the image plane in pieces.  It's like using a loupe to examine an object up close.  In that moment, you realize an eyepiece is nothing but a magnifier and the image plane is the object being examined.

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