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Binocular Questions

  1. Jun 16, 2009 #1
    Does anyone have any samples images from 7x50, 15x70, and 25x100 binoculars as pointed towards objects in space? I'd like to get a nice telescope one day, but right now, I'd like to buy 1 or 2 binoculars that I can use in my back yard for looking up at the stars and learning about the sky.

    I've read that a good pair of binoculars can be better than many low-mid sized telescopes for some objects due to increased field of view, ease of viewing through 2 eyepieces, and also due to the fact that the light in my city negates many opportunities to view deep-sky objects with a telescope.

    I've read I can "see" galaxies and nebulae (which would be great), but how well? I've searched and searched and read many articles, but I really want to see these with my own eyes before I decide what to buy. Or perhaps I just want to know what to expect. I'd just like to look at some samples pictures.
     
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  3. Jun 17, 2009 #2

    Chronos

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    I would vote 7x50 to start, with 15x70 as a close second, depending on budget. With 25x100 you will need a tripod. I dont consider that very practical. It will be difficult enough to hold that 15x still enough to get decent views.
     
  4. Jun 19, 2009 #3
    I appreciate the reply. I do plan on starting with 7x50's. I was hoping someone could post or point me to some images taken with binoculars or with telescopes of similar power. I want to know what the views will look like.
     
  5. Jun 19, 2009 #4

    russ_watters

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    Hmm.... Images from a camera wouldn't be very helpful because the brightness is vastly greater in a photo than what you can see with your eyes. That makes your request pretty diffulct too - it wouldn't be very easy to simulate the bightness of an image through binoculars. I can tell you.....

    -Jupiter, Saturn, and Venus would probably not be recognizable with 7x50s, but would be with 25x100, though not terribly impressive.
    -For deep sky objects, star clusters would certainly be in play, and that is what they are best for. Galaxies and nebulae would be a little difficult. They'd certainly be big enough, but brightness would be problematic. It isn't any better for binos than for a low focal ratio telescope. So unless open star clusters are your primary concern, I don't know that there is a big advantage to binoculars there.
    -Most people seem to favor binoculars for learning the night sky. I like to learn, but I also want to see what I can see. I'm more of an instant gratification person, so I very much prefer a telescope, even a small one, to a pair of binoculars. You just can't see as much (that I care about) with binoculars as with a telescope.
    -Obviously, budget is an issue. If the options are binos or nothing, certainly binos would win. But for me, I preferred even a crappy old K-Mart Special refractor to binos. Seeing Venus, Jupiter, Saturn, and the moon through a telescope were reason enough for me.
     
    Last edited: Jun 19, 2009
  6. Jun 19, 2009 #5
    I started astronomy this year with an old pair of birding 16x50 binoculars. I am young, and so I never have any issues with holding them still. What I can tell you is that if you live in a light polluted area, deep sky objects will be difficult. From my location, which is about 20 miles from a major urban area, the dimmest object I can find is M31, the Andromeda galaxy, and only on a good night. Star clusters are very visible, especially the Pleiades, Hyades, Beehive, and Ptolemy's cluster. The only nebula that I have been able to see is the Great Orion Nebula.

    I sometimes travel to a very dark location that has visibility down to magnitude 6.5 with the naked eye. From this location I can see a variety of galaxies, such as M81 and M82, although the most I can see is a faint blur. The same is true of globular clusters, which just look like fuzzy stars.

    That said, I recently purchased an equatorial mount 5 inch primary Newtonian, and I can say the binoculars really are a lot more convenient and useful for basic astronomy.
     
  7. Jun 19, 2009 #6

    Nabeshin

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    Pray tell, what does being young have to do with holding binoculars steady (assuming "old people" don't all have Parkinson's disease)?
     
  8. Jun 20, 2009 #7
    Nabeshin, I am so sorry if I offended you. You clearly have revealed a profound age bias that I must take proactive steps to overcome. I have no idea where I could have gotten the new-fangled notion that elderly people tend to have http://content.karger.com/ProdukteDB/produkte.asp?Doi=22127".

    Regarding the binoculars dilemma, I would say that you may want to clarify exactly what objects you want to see. If you are stuck in your city location, buying a really high resolution pair of binoculars will not help counteract the light pollution, as the increased light gathering capability would just make them gather more light pollution with the starlight. With telescopes, there are special eyepieces available that can filter out common city light wavelengths.
     
    Last edited by a moderator: Apr 24, 2017
  9. Jun 20, 2009 #8

    russ_watters

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    I'm 33 and don't use binoculars very often, but I have used them over the years. IMO, binocular observing, even with relatively low power, requires a tripod. It may not be as big an issue with terrestrial viewing, but when you are looking at dim objects in the sky, it is.
     
    Last edited: Jun 20, 2009
  10. Jun 20, 2009 #9

    russ_watters

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    I've made an attempt at some simulations. My laptop display is 13"/1680 pixels wide and sitting on my lap is 22" from my face. That's a field of view of 33 degrees. You'll need to adjust your display to this scale using some geometry. Ie, if your monitor is 13" across but only 1280 pixels wide, you'll need to locate it 22*(1680/1280)=29" from your face to get the same image scale.

    Note, these simulations show image scale only. They are not accurate simulations of brightness or color saturation. What you see with your eyes will be dimmer and less saturated, except when looking at the moon. Also important to note, though the image scale is accurate, the field of view is only somewhere around half what you would get with binoculars.

    The first three simulations are the Pleiades, a good open star cluster visible to the naked eye (often mistaken for the little dipper).
     

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  11. Jun 20, 2009 #10

    russ_watters

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    These are the Perseus double cluster.

    I took a photo that looks similar to the last picture, but with a slightly smaller field of view and since you can't see the blackness around the cluster, it loses the effect. I'll have to try to get a wider view this summer when it is out...
     

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    Last edited: Jun 20, 2009
  12. Jun 20, 2009 #11

    russ_watters

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    The Moon. It will actually look better than these pictures. The artwork is not very good (these are from Starry Night)...
     

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  13. Jun 20, 2009 #12

    russ_watters

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    And last, Jupiter and some moons at 7x and 25x. Jupiter will look close to this. Theoretically, the moons should be naked eye visible, but they usually aren't. They are visible even with only 7x binos.
     

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  14. Jun 20, 2009 #13

    turbo

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    7x50's are a nice starting point, and are commonly available used. If you buy new binoculars and can afford it, buy base level binos from a very reputable maker. The quality of the optics and coatings from the better makers often extends to their basic models, though you won't get the bells and whistles of the more $$$ models.

    I got my Nikons on sale at LL Bean years ago, and they are my most-used astronomical equipment, plus I keep them handy to look at birds, wildlife, etc. Binoculars and a decent set of charts can get you a long way. Almost any optical aid will help, but IMO, 7x50s are the best choice for portability, light-gathering, light weight (you WILL get arm-weary holding much larger binoculars and looking up!), and all-around usefulness. You can take the 7x50s on hikes and bird-watching jaunts, but the larger binoculars will stay at home and be used only for astronomy.
     
  15. Jun 20, 2009 #14
    Thanks guys! All the responses are great! Especially the pictures! That's exactly what I was looking for. I'll be starting with 7x50's, and will be getting 25x100's in a year. I can have both for under $500 combined, which meets with my current financial situation more appreciably! When I finally get a telescope, I'll know much more about what I'm doing.

    I'd like to be able to see Jupiter, Saturn, the Andromeda Galaxy, and the Orion Nebula. Those are my priorities. Looks like I won't really see those with 7x50's, but I'm hoping the 25x100's will get me there!

    Mike
     
  16. Jun 20, 2009 #15
    I have Celestron 12x60mm binos and can just make out that Saturn has rings. (It mostly looks oblong.) Andromeda and Jupiter plus 3 or 4 of its moons are easy. The binos were very inexpensive and are decent quality. I would say that they are best used with a tripod but can be hand held for short periods of time.

    Let us know what you buy!
     
  17. Jun 21, 2009 #16
    I have some Orion 20 x 80 that I built a parallelogram mount for(like http://www.bigbinoculars.com/stedivu.htm" [Broken]) except out of cherry wood (for about $30) and they work really great. Set up is quick (5 minutes). I love them.
     
    Last edited by a moderator: May 4, 2017
  18. Jun 30, 2009 #17
    You can easily see Andromeda with the naked eye. Using my 8x40 binos I can see galaxies like M81, M33, M101 and M51 and then 8x40 isn't even that great a bino to see faint objects.
     
  19. Jan 10, 2010 #18
    I finally got my first binoculars, Celestron 12x50s, and ever since they arrived in the mail I've had completely overcast skies every single night! It's 5 straight nights now! Grrr....
     
  20. Jan 11, 2010 #19
    I have Nikon 10x50 EX and 7x50 CF binos. The 10x50 (EX are more expensive) actually have the same field of view as the 7x50 and so behave the same when holding steady. I used some cheap 15x70's for a while but they were pretty hard to hold for long and weren't much better than good 10x50's.

    What you can see really depends on how dark your skies are. 10x50's should be able to see Jupiter's big 4 moons, and a hint of Saturn's rings. Lots of faint objects are possible too, but it varies immensely place to place.

    IMO, once your binos get too big and you are carrying a tripod around, you might as well go and buy a 6" Newtonian scope.
     
  21. Jan 16, 2010 #20
    It took 8 nights of waiting for me to get some clear skies! I decided to focus my first attempt at skywatching on Orion. I was impressed with how clear the binoculars were, but was a little disappointed at how much light pollution I have. I was hoping to see the Orion nebula, but it is nothing more than a faint, gray, wisp through my binoculars. I think I'll buy a tripod and stabilize the image a little; that should help. I probably also need to commit some serious outside time in the cold to my eyes can fully adjust.

    After Orion, I made my way up to the Plaedes, which was VERY cool. I really liked finding it using a star map. I've never done that before, and it was neat to "discover" it!

    Lastly, I was able to see coloration of stars. Red, bluish, and yellow. It was pretty cool!

    Fortunately, I live pretty close to the mountains, and can make my way up there eventually to view the skies.

    Mike
     
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