What can I get to improve telescope

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In summary, a good accessory for a planetary scope is a Barlow lens. magnification is not as important as resolution, but there is a way to magnify things without compromising clarity. A good camera for a scope can be a cheap solution if you are not serious about astronomy. Be wary of adding magnification as your scope becomes more expensive and you may find yourself needing a bigger and better scope.
  • #1
Saladsamurai
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Hey there, I am new to this particular forum. I recently picked up a Meade starting level telescope (nothing electric). I caught a glimpse of my first planet last night and it was rad! I do not know which planet it was, but I assume it was Jupiter as it had some dots around it...they were either Jupiter's moons or I am mistaking and they were just distant(er) stars.

The planet was exremely small in my viewfinder though, so my question is this:Can someone tell me. . . What is a good accessory to add to my scope to help me see things "better"...Is there a recomended lense?

I have a Barlow lense, but I do not seem to benefit from it. I also have the lenses my scope came with: 25mm (I use that to spot things) 9mm(gets me sharper, I think) and a 17mm (I have not found a use yet)...

I understand that magnification is not as important as resolution, but is there a way I can magnify things to a certain extent without compromising clarity?

Thanks,
Casey
 
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  • #2
Saladsamurai said:
Hey there, I am new to this particular forum. I recently picked up a Meade starting level telescope (nothing electric). I caught a glimpse of my first planet last night and it was rad! I do not know which planet it was, but I assume it was Jupiter as it had some dots around it...they were either Jupiter's moons or I am mistaking and they were just distant(er) stars.

The planet was exremely small in my viewfinder though, so my question is this:Can someone tell me. . . What is a good accessory to add to my scope to help me see things "better"...Is there a recomended lense?

I have a Barlow lense, but I do not seem to benefit from it. I also have the lenses my scope came with: 25mm (I use that to spot things) 9mm(gets me sharper, I think) and a 17mm (I have not found a use yet)...

I understand that magnification is not as important as resolution, but is there a way I can magnify things to a certain extent without compromising clarity?

Thanks,
Casey

What is the focal length of your scope? A good planetary scope will have a fairly large focal length. A rough guide for the maximum reasonable magnification that your scope will produce is 50 times the diameter of the mirror in inches. A 4" mirror will at best produce useable images up to 200X magnification. That means that when viewing is optimal, 200X is the best you will do. At that magnification images will be shaky and will streak across your field of view.

You may want to consider a low cost camera for your scope. I've seen some pretty decent images for planets using an unguided 4" scope. If you are serious about your hobby, try to buy the best accessories. These will be real investments that you can carry on to bigger and better scopes. I like the Televue line of lenses and magnifiers. If you go with a camera, a good 2X or 3X magnifier can be a real help. Televue has a magnifier they call the Powermate that will be just what you are looking for.

Beware! As you buy better and better accessories (some as expensive as the scope you are now using) you are going to want (ie 'need') bigger and better scopes and mounts and cameras and locations and temperature controllers and image software and coma correctors and time and...

http://www.televue.com/home/default_3.asp [Broken]
http://www.telescope.com/jump.jsp?itemID=0&itemType=HOME_PAGE
http://www.meade.com/
 
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  • #3
The telescope is listed in the next thread down...it is a 1000mm focal length Newtonian reflector.

The best combination you'll probably be able to use is the 9mm and the barlow (I assume it is a 2x barlow). So that gives 1000/9*2=222x magnification. The maximum theoretical magnification is 350-400x, so you can use a 2.5x or 3x barlow to get more magnification. I wouldn't get smaller than that 9mm eyepiece, as they can be tough on your eyes.

Jupiter rises near midnight, so if you were out late and saw up to 4 dots all along a straight line with the planet, that was Jupiter and they were the moons. At 222x magnification, you should easily be able to see horizontal stripes and the Great Red Spot if it is in the right position. The problem with Jupiter right now, however, is that it stays low to the horizon this year and as you are finding out, the atmosphere really kills the view. Adding magnification just makes it a bigger, fuzzier ball that even seems to 'swim' across the eyepiece. Most people when first looking through the telescope remark about how small the objects are, but your eyes are really good at resolving small details, so you should sill be able to see a lot.

Stability on all telescopes is a big, big issue. You'll probably have to track slowly, allowing the planet to drift through the field of view while you aren't touching the controls, to make it stable. Even with my big, stable, motorized telescope, I have to tell people not to touch the eypiece, because they won't see a thing if they do. You'll get the hang of it. If there is an option for a motorized-drive (or if you are technically inclined...), that would allow you to track objects through the sky without touching the controls, making it much more stable.

If you can get out not long after sunset, try finding Saturn - it is a very rewarding view, and since it is high in the sky, it should be much clearer.
 
  • #4
Russ, I am not sure what you meant by the next thread down. . . I do not think they stay in order for too long.

I have gotten the hang of not touching anything while viewing, though getting Jupiter into focus is a real shaky time..

However, No matter what combination of lenses I use, I cannot seem to see the features of Jupiter (i.e. the horizontal bands). All I can see is a bright dot with a string of 4 smaller white dots surrounding it.

I know that my telescope is not the greastest, but I am quite sure that I should be able to make out some more distinct features.

The largest that the planet appears in my viewfinder is the actual size of this asterisk-->*

The image is quite crisp, but all of the sharpness in the world doesn't help if the image is too small for the human eye too resolve.

I have a 2X Barlow that I bough with the scope. Along with three other lenses. These are the specs:

114mm diameter, 1000mm (f/8.8) focal length reflector; rack-and-pinion 1.25" focuser with sleeve lock; equatorial mount with variable-tension locks; two 1.25" eyepieces (MA9mm and MA25mm) with rubber eyecups; diagonal mirror (1.25") Lenses:eek:ne 9mm (78x) and one 25mm (28x)
and one 17mm(23x)

I will keep trying:tongue2:
 
  • #5
Does the telescope require that you collimate the mirror? Could the collimation be a little off?
 
  • #6
chemisttree said:
Does the telescope require that you collimate the mirror? Could the collimation be a little off?

I am sorry chemistry; I have no idea what this means:redface: I do not recall hearing this term collimation in the instructions.
 
  • #7
Saladsamurai said:
Russ, I am not sure what you meant by the next thread down. . . I do not think they stay in order for too long.
True - I probably should have linked it for him...
However, No matter what combination of lenses I use, I cannot seem to see the features of Jupiter (i.e. the horizontal bands). All I can see is a bright dot with a string of 4 smaller white dots surrounding it.
Is it really just a dot or does it have a definite size and disk shape? It is possible that it is due to atmospheric conditions lowering the contrast of the image, but it is possible that the telescope needs to be collimated like chemistree suggested, but only if you are using very high magnification.

Collimation is a process for aligning the components of the telescope - for yours, that means adjusting the secondary mirror. I wouldn't worry about it quite yet.
I know that my telescope is not the greastest, but I am quite sure that I should be able to make out some more distinct features.
You absolutely should - it is possible to see the banding even with a large pair of binoculars.
The largest that the planet appears in my viewfinder is the actual size of this asterisk-->*
"viewfinder"? You mean the eyepiece?
The image is quite crisp, but all of the sharpness in the world doesn't help if the image is too small for the human eye too resolve.

I have a 2X Barlow that I bough with the scope.
If the image is crisp, then it probably isn't an atmosphere or collimation issue, but simply a magnification issue. It sounds like you haven't used the barlow yet - definitely give it a try.
 
  • #8
Yes, I meant the eyepiece. And I have tried the Barlow. Whenever I encounter a problem of any sort, I usually investigate as thouroughly as I can on my own before posting here; I think I have tried every combination with the Barlow and other lenses; so maybe collimation is a problem. . . but I will attempt again tonight before messing with the scope.

I thought that with the 2x Barlow and the 28x 25mm lense it would be enough. I will try again with the 78x 9mm and the Barlow even though it is hell on the eye.


russ_watters said:
True - I probably should have linked it for him... Is it really just a dot or does it have a definite size and disk shape?
1. Do you remember the name of the thread?
2. It does have definite shape and size. . . I use the word dot to emphasize just how small it appears though. I realize it will not be "huge" but it is ...this is so difficult to describe with words...
I guess I could say that it is defined enough that I can see it is a disk (i.e. the edges are not blurred) but I can not make out any distinct features other than that (because of the size).
 
  • #9
I saw the other thread. Meade EQ-AST 1000 mm short tube. It has a relay lens in it to shorten the tube and increase the focal length. Is the relay lens achromatic? It is definitely not apochromatic... If it isn't, you could be having a problem with the lens causing the image to be fuzzy. The blue light will have a slightly different focus than the red resulting in loss in contrast.
A contrast enhancer filter or a "mars" filter could do the trick.

http://www.telescope.com/shopping/p...e=PRODUCT&iMainCat=6&iSubCat=22&iProductID=83
http://www.lumiconfilters.com/filter-catalog.php?cid=18&cn=Lunar+&+Planetary+Filters
 
  • #10
No, chemistree, it is a Newtonian reflector - no lenses except in the eyepiece. Just a primary and secondary mirror.
 
  • #11
From the Meade site:

SPECIFICATIONS
Meade Model 114EQ-AST (P/N: 04056) — Basic model includes the same diameter mirror as above, but includes a special relay lens which shortens the tube length and yields a 1000mm focal length (f/8.8). Includes a somewhat smaller mount and tripod than the model above. The exact same accessories are present in both models...

http://www.meade.com/starterscopes/eq_series.html [Broken]

Does the term 'relay lens' refer to a mirror?
 
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  • #12
This is the scope I have http://shopping.discovery.com/product-56911.html?endecaSID=112B1C66EFF0 [Broken]...

I tried agin last night but I still can't discern an distinguishabl features of Jupiter. Crapass.
 
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  • #13
Saladsamurai said:
This is the scope I have http://shopping.discovery.com/product-56911.html?endecaSID=112B1C66EFF0 [Broken]...

I tried agin last night but I still can't discern an distinguishabl features of Jupiter. Crapass.

Yes, I followed the link on the other thread. The EQ-114 ASTR. I assume that the 'R' stands for the Relay lens? Is there any other glass (besides the 2 mirrors) between the opening at the top of the scope and the focusser? I still think a filter might be a cheap (try) fix.
 
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  • #14
I have never looked inside, so I really don't know. I was trying not to take anything apart, but I might have too. The only reason I did not think it would be the filter is that it is not that I can't idetify Jupiter's features due to clarity, but due to size. It is just so small...
 
  • #15
You should be able to see any lenses by inspection of the scope. No tools required. There shouldn't be any glass covering the opening on top. You should see the secondary mirror in the same plane as the focusser. The lens (if there is one) might be in the focusser tube.

In my 4.5 in reflector, Saturn looks like a pea held at arms length when I use my 2X barlow and 9mm combination. The magnification with this combination is about 100X. Your magnification will be roughly twice that at 222X. You should see some detail and the image should NOT look tiny but definitely disc-shaped.
 
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  • #16
chemisttree said:
From the Meade site:

SPECIFICATIONS
Meade Model 114EQ-AST (P/N: 04056) — Basic model includes the same diameter mirror as above, but includes a special relay lens which shortens the tube length and yields a 1000mm focal length (f/8.8). Includes a somewhat smaller mount and tripod than the model above. The exact same accessories are present in both models...

http://www.meade.com/starterscopes/eq_series.html [Broken]

Does the term 'relay lens' refer to a mirror?
I stand corrected - I've never heard of such a thing. Essentially, it is an integral Barlow lens, in the middle of a Newtonian reflector. And if there is only one element, it certainly would yield some chromatic aberration.
 
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  • #17
Jupiter is small at 220x magnification, but it should be big enough to see stripes. Still, you can get a good 3x barlow from Orion (www.telescopes.com) for around $50 and that'll help increase the magnification.

With the 9mm and the 2x Barlow, the view should look something like this (though with less contrast):
 

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  • #18
Wow! Great pic Russ! One of yours?
 
  • #19
chemisttree said:
Wow! Great pic Russ! One of yours?
Nooooo - it's a screenshot from Starry Night! I do have a recent one that is half-decent, though. I'll post it later.
 
  • #20
By less contrast, you mean the bands won't be as sharply defined right?
 
  • #21
Right.

....
 
  • #22
I saw Jupiter with a d:114 Focal:900mm with a 10mm eyepiece and a 2x barlow, that is 180x magnification, i saw it the size of russ image, but not so colorfull, also with less contrast, but if you try to do a little more focus with your eye you can barely see the stripes!
In saturn you can clearly see the rings also!
 
  • #23
Burnsys said:
I saw Jupiter with a d:114 Focal:900mm with a 10mm eyepiece and a 2x barlow, that is 180x magnification, i saw it the size of russ image, but not so colorfull, also with less contrast, but if you try to do a little more focus with your eye you can barely see the stripes!
In saturn you can clearly see the rings also!

I looked a Jupiter last night with my 4.5" Newt. The bands were just visible... even with a full moon! They were much more apparent with my contrast enhancer filter.
 
  • #24
This sucks:mad:
 
  • #25
Saladsamurai said:
This sucks:mad:

Still no joy? You really should see a planet about the size of this :confused: (viewed at ~20" from a 15" monitor) in your eyepiece using the barlow and the 9mm. Banding should be evident if the moons around it are sharp. What time are you trying to observe? Later in the night (around midnight) should be better for you. Are you really looking at Jupiter? Go out tonight and find the moon. Jupiter is right next to it. Was that what you were looking at? Do the moons around Jupiter appear to be in line, one on one side and three on the other?

Of course, I'm at latitude 30 degrees and Jupiter rises to about 30 degrees above the horizon at midnight. For you it will get to about 25 degrees above the horizon at midnight. Look almost due south: 165 degrees on the compass if you include the -16 degree magnetic declination or 180 degrees on the compass if you ignore the correction for declination.
 
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  • #26
chemisttree said:
Still no joy? You really should see a planet about the size of this :confused: (viewed at ~20" from a 15" monitor) in your eyepiece using the barlow and the 9mm. Banding should be evident if the moons around it are sharp. What time are you trying to observe?

None:mad: I see a disk of half that diameter with the 2x Barlow and 9mm. I am convinced that my scope is garbage:mad: The mount is garbage; the RA slips; the tripod is shakier than a bobble-head with Parkinson's...

When I use the 2x Barlow and 9mm, I absolutely cannot get a perfectly sharp image like I can without the Barlow using only the 9mm.

As I turn the focus knob the image goes from blurry to increasingly sharper but than it reaches a critical point where it just starts getting blurry again (without ever getting crisp).

I don't know what else there is I can do. I could spend more money on things to try to make it work better, or just cut my losses and look for another scope.

I wonder if this "relay lense" as anythong to do with it? I wonder if that was just a garbage idea Meade came up with to help make the tube shorter, but with the mass producing of garbage "relay lenses" came the compromise in clarity.

I could be just talking out my arse though:rolleyes:

also: Yes. It is indeed Jupiter I am looking at.
 
  • #27
The relay lenses may have something to do with it, but the fact that Jupiter never gets above 25 degrees has a lot to do with it too. Try Saturn and Venus...
 
  • #28
Last night I looked a Jupiter when it was only 25 degrees above the horizon. I saw 4 moons clearly (all on one side now) but no bands or detail. I think Russ is right... try for something like Saturn earlier in the evening.
 
  • #29
As I turn the focus knob the image goes from blurry to increasingly sharper but than it reaches a critical point where it just starts getting blurry again (without ever getting crisp).
I have the same problem with my 2x barlow, you have a more narrow area to do focus, and you have to move it with much more precision.
Another problem i noted is that when i use the barlow i see a red and blue halo arround jupiter, i think it has to do with the low quality of the barlow lens..

Yesterday i took a very very cheap USB CMOS webcam, and with a film canister could take videos from the moon with my telescope. The problem that i am having is when i point at jupiter, the webcam has an AutoExposure control, but i can not set it manualy, so i can see Jupiter and it's moons, but Jupiter looks completely staturated white. I was thinking to place some kind of "improvised Filter" to block some of the light.

One question: I know that a 900mm telescope with a 10mm Eyepiece, will give me, 90x magnification. But with the webcam at Prime focus i am misiing one variable, how do i calc the maginification? Aparently with the webcam at prime focus i get more magnification that with te 10mm eyepiece and the 2x barlow, could it be?

Sorry my english!
PD: My telescope mount sucks!
 
  • #30
Burnsys said:
Another problem i noted is that when i use the barlow i see a red and blue halo arround jupiter, i think it has to do with the low quality of the barlow lens..
Yes, though if the red is on one side and the blue on the other, that's caused by the atmosphere when the planet is low on the horizon.
Yesterday i took a very very cheap USB CMOS webcam, and with a film canister could take videos from the moon with my telescope. The problem that i am having is when i point at jupiter, the webcam has an AutoExposure control, but i can not set it manualy, so i can see Jupiter and it's moons, but Jupiter looks completely staturated white. I was thinking to place some kind of "improvised Filter" to block some of the light.
Almost every webcam will allow you to disable the autoexposure and set it manually. Try AMCap (google it) to do the capturing - it has good menus for changing webcam options.
One question: I know that a 900mm telescope with a 10mm Eyepiece, will give me, 90x magnification. But with the webcam at Prime focus i am misiing one variable, how do i calc the maginification? Aparently with the webcam at prime focus i get more magnification that with te 10mm eyepiece and the 2x barlow, could it be?
It could be true, but what you need to do the calculation is resolution of the final image on your screen and distance from your eye. I do the calculation manually with trigonometry (actually, I have it plugged-into a spreadsheet).
 
  • #31
Saladsamurai, try looking at www.clearskyclock.com to see what your sky conditions are like. It doesn't necessarily follow that a very clear night is good for observing due to bad transparency (which reduces contrast) or bad "seeing", which is mostly turbulent air causing the image to fail to become sharp.

Attached is an image I just took a few minutes ago using techniques that enhance detail. Cloud cover is near near-perfect, but both seeing and transparency are bad. The result: blurry and low contrast.

The second image, I took through a very thick haze, but it was dead calm, making the seeing good.
 

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  • #32
russ_watters said:
Yes, though if the red is on one side and the blue on the other, that's caused by the atmosphere when the planet is low on the horizon.
You where right! i tried it today when Jupiter was high and the effect was almos inexistent

Almost every webcam will allow you to disable the autoexposure and set it manually. Try AMCap (google it) to do the capturing - it has good menus for changing webcam options.
I couldn't found it, all i could found was an "Stop AE (Auto exposure)" option, but i had to point a flashlight to the camera and select the option to keep the autoexposure in that level :uhh:

Well finaly here are my first pictures from jupiter, filmed in 640x480 and then stacked in registrax using your tutorial :smile:

The first picture is how it looked with the auto exopsure, at least i could see the moons! :yuck:
 

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  • #33
Thanks for that link Russ. So now "seeing" is my primary concern on the chart correct. Here is a link to my area http://cleardarksky.com/c/PlmIsldMAkey.html

I just went out and viewed at 11:00 pm. If I am reading the chart correctly, the seeing should have been average correct?

I definitely saw things better tonight, but still no bands:frown: I noticed on the site it mentioned things looking like they were under a layer of rippling water during poor conditions of some sort.

What causes this? This seems to be what I have been experiencing a lot of the time.

Also: There appeared to be something small (relative to Jupiter) and bright red to the lower-right of Jupiter...what is that?? I thought it was a planet, but according to Skychart it was not.
 
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  • #34
That level of seeing isn't very good, though it is slightly better than what I had earlier tonight, and you see my results...

The rippling-water effect is the seeing and it is atomspheric turbulence caused by thermal effects (wind, updrafts, etc.). It is worstened by the planet being low on the horizon, since you have to look through much more of the atmosphere. So...

Look for Saturn!

I don't know what that object was below Jupiter - there was an 8th magnitude star in the area, though (a fair amount dimmer than the moons).
 
  • #35
I will look for Saturn tomorrow; however, I don't see it being that much better (granted I know nothing about astronomy) but if is position that matters: I would have to get to Saturn by 9pm as it will be over 30deg to the horizon. Any later and I it looks like it will be around 24, which is what Jupiter was at all night.

Also, you probably already know, but on June 30, Saturn and Venus will cross orbits, so you should be able to see them both in the same eyepiece.

That red thing was awesome. No clue what it was, but it looked like a ruby.
 
<h2>What are the different types of telescopes and their advantages?</h2><p>There are three main types of telescopes: refracting, reflecting, and catadioptric. Refracting telescopes use lenses to gather and focus light, reflecting telescopes use mirrors, and catadioptric telescopes use a combination of lenses and mirrors. Refracting telescopes are best for viewing planets, reflecting telescopes are best for deep sky objects, and catadioptric telescopes offer a balance between the two.</p><h2>What are the key features to consider when purchasing a telescope?</h2><p>The most important features to consider when purchasing a telescope are the aperture (diameter of the primary lens or mirror), focal length, and focal ratio. These factors determine the telescope's light-gathering ability, magnification, and field of view. Other important factors include the mount, eyepieces, and accessories.</p><h2>What are the benefits of adding a computerized mount to a telescope?</h2><p>A computerized mount, also known as a GoTo mount, can greatly enhance the viewing experience with a telescope. It uses a database of celestial objects to automatically locate and track them, making it easier to find and observe specific targets. This is especially beneficial for beginners or those interested in astrophotography.</p><h2>How can I improve the image quality of my telescope?</h2><p>There are several ways to improve the image quality of a telescope. One option is to upgrade the eyepieces, which can greatly impact the clarity and sharpness of the image. Another option is to use a Barlow lens, which increases the magnification without sacrificing image quality. Additionally, regularly cleaning and collimating the optics can also improve image quality.</p><h2>Is it possible to upgrade an existing telescope?</h2><p>Yes, it is possible to upgrade an existing telescope. Some common upgrades include adding a motorized mount, upgrading the eyepieces, or replacing the primary lens or mirror with a larger one. However, it's important to research and carefully consider the compatibility and cost of these upgrades before making any changes to your telescope.</p>

What are the different types of telescopes and their advantages?

There are three main types of telescopes: refracting, reflecting, and catadioptric. Refracting telescopes use lenses to gather and focus light, reflecting telescopes use mirrors, and catadioptric telescopes use a combination of lenses and mirrors. Refracting telescopes are best for viewing planets, reflecting telescopes are best for deep sky objects, and catadioptric telescopes offer a balance between the two.

What are the key features to consider when purchasing a telescope?

The most important features to consider when purchasing a telescope are the aperture (diameter of the primary lens or mirror), focal length, and focal ratio. These factors determine the telescope's light-gathering ability, magnification, and field of view. Other important factors include the mount, eyepieces, and accessories.

What are the benefits of adding a computerized mount to a telescope?

A computerized mount, also known as a GoTo mount, can greatly enhance the viewing experience with a telescope. It uses a database of celestial objects to automatically locate and track them, making it easier to find and observe specific targets. This is especially beneficial for beginners or those interested in astrophotography.

How can I improve the image quality of my telescope?

There are several ways to improve the image quality of a telescope. One option is to upgrade the eyepieces, which can greatly impact the clarity and sharpness of the image. Another option is to use a Barlow lens, which increases the magnification without sacrificing image quality. Additionally, regularly cleaning and collimating the optics can also improve image quality.

Is it possible to upgrade an existing telescope?

Yes, it is possible to upgrade an existing telescope. Some common upgrades include adding a motorized mount, upgrading the eyepieces, or replacing the primary lens or mirror with a larger one. However, it's important to research and carefully consider the compatibility and cost of these upgrades before making any changes to your telescope.

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