Got a scope about two weeks ago. (Should have searched the net for a site like SignAstro first!!!!).
I would like to know what size EP I can use while will yield best clear (close-up) view without causing blur effect. I was told that a 4 or 6 mm EP will cause blur.
Apperture : 3" : Focul length : 700mm, f/9 (I was given a 10 & 20 mm EP as standard purhcase.
Just started on sky watching after my youngest boy wanted to see the stars closer. I have found the site to be very usefull as most partcipants are clear and careful in sharing their learnings. Thanks a plenty.
Advice on EP
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Firstly, welcome to Singastro forums! Usually, a rule-of-thumb is 50x for every inch of aperture. So your scope will theoretically support up to 150x. You will need a 700/150 = 5mm ep to give you that magnification. But you will generally find that for your scope, this magnification will only work well on the brightest objects such as the moon, jupiter and saturn. The latter two are not conveniently visible this time of the year, but will be an awesome sight when they do become visible.
The quality of the eps also play an important role. I suggest you look for some good quality but affordable plossl eyepiece in the 25mm to 30mm range to give you a wide field of view so you can look at the brighther open clusters like M6 or M7, which are beautiful and relatively easily visible even in our light-polluted skies. Your 10mm and 20mm will give you awesome views of the moon's craters. Make sure you observe the moon at a time other than full moon for the most details. Perhaps you can give us more specific information about the make of your scope and eyepieces, so others can chime in with more specific recommendations.
cheers
Chee Chien
The quality of the eps also play an important role. I suggest you look for some good quality but affordable plossl eyepiece in the 25mm to 30mm range to give you a wide field of view so you can look at the brighther open clusters like M6 or M7, which are beautiful and relatively easily visible even in our light-polluted skies. Your 10mm and 20mm will give you awesome views of the moon's craters. Make sure you observe the moon at a time other than full moon for the most details. Perhaps you can give us more specific information about the make of your scope and eyepieces, so others can chime in with more specific recommendations.
cheers
Chee Chien
We do it in the dark...
Portaball 12.5"
Takahashi Mewlon 210
William Optics 110ED
...and all night long!
Portaball 12.5"
Takahashi Mewlon 210
William Optics 110ED
...and all night long!
Thank you Chee Chien.
Basically I went on to buy a FIRSTSCOPE 76, 3" NEWTONIAN
EQUATORIAL TELESCOPE @ shop at Science Centre. I was told that it is an entry level scope. It came with Celetron 10 & 20 mm / 1.25" barrel EP.
Once again thanks for the advice. I have been reading into the various forums and see that there is a good healthy community of Astro enthusists. glad to have found this site.
kalai KC
Basically I went on to buy a FIRSTSCOPE 76, 3" NEWTONIAN
EQUATORIAL TELESCOPE @ shop at Science Centre. I was told that it is an entry level scope. It came with Celetron 10 & 20 mm / 1.25" barrel EP.
Once again thanks for the advice. I have been reading into the various forums and see that there is a good healthy community of Astro enthusists. glad to have found this site.
kalai KC
hmm.. seriously consider getting something like a gd 32mm plossl. that would be used far more than any other eyepiece inside ur box, since it would provide gd low power views to help make hunting for objects more easily. the entry level scopes sold nowadays are getting reasonable in terms of quality. however i felt that the cheaper bundled eyepieces should be upgraded to quality plossl or similar eyepiece if possible.
~MooEy~
~MooEy~
Hi,
Consider getting a 2X barlow and a 30mm Plossl. That will allow your 10mm eyepiece to be like a 5mm, and the 30mm like 15mm while preserving eye relief.
If the views are blur, make sure the scope is collimated i.e. the primary (large) mirror, secondary (small) mirror and eyepiece are in the optimal alignment.
If you are unsure how to collimate it, just ask and the newtonian users here would be happy to help. Look through the Buy and Sell section. There are a number of sellers selling off their eyepieces. The Plossl is an excellent low-cost, multi-purpose design.
BTW, don't expect the stars to seem closer just by increasing the magnification. Stars (other than the sun of course!) still seem like pinpoints of light on all amateur scopes.
Kay Heem
Consider getting a 2X barlow and a 30mm Plossl. That will allow your 10mm eyepiece to be like a 5mm, and the 30mm like 15mm while preserving eye relief.
If the views are blur, make sure the scope is collimated i.e. the primary (large) mirror, secondary (small) mirror and eyepiece are in the optimal alignment.
If you are unsure how to collimate it, just ask and the newtonian users here would be happy to help. Look through the Buy and Sell section. There are a number of sellers selling off their eyepieces. The Plossl is an excellent low-cost, multi-purpose design.
BTW, don't expect the stars to seem closer just by increasing the magnification. Stars (other than the sun of course!) still seem like pinpoints of light on all amateur scopes.
Kay Heem