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Pages: 1 startrend12 newbie Reged: 05/24/12 Loc: N.E. Ohio NexStar 8SE - Visible sizes of planets and DSOs       #5358143 - 08/08/12 02:17 PM Edit   Reply   Quote Quick Reply   Hi All, This forum is great, I learned a lot here. This is my first post,so, please bear with me. I did read through many posts before asking this question, I apologize if this has been asked before. I have recently bought a NexStar 8SE (EPs: 25mm Plossl and Meade 8-24mm Zoom) My question is about the sizes of the planets that are visible through this scope. I see Saturn and Jupiter about the size of a pencil eraser. Colors/shades are OK on Saturn and it's rings but Jupiter looks washed out. Is this the usual size (and color) you see of these planets in this telescope? Also, the Ring Nebula seemed really tiny and barely visible, so was Sombrero Galaxy(M104) which was very hard to see in the first place (I am not comparing Hubble pics or images taken with cameras and better optics). My Setup: NexStar 8SE 25mm Celestron Plossl 8mm-24mm Meade Zoom Orion Variable Polarizing Moon Filter Moderate to low light pollution Allowed Telescope to cool down Thanks in advance. SCS Post Extras:       Bob Griffiths Getting Grouchy Reged: 10/10/05 Loc: Frederick Maryland Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: startrend12]       #5358339 - 08/08/12 03:58 PM Edit   Reply   Quote Quick Reply   With the 25 mm eyepiece you are getting 81x.. The planets will be exactly the same size in in your scope... 81x in any other scope will show you exactly the same size planet.. NOW if you happen to be using a wide field of view eyepiece the actual size of the planet will be the same BUT it will appear smaller because it is surrounded by a heck of a lot more space.. Jupiter is one super large and bright Planet that just happens to be pretty close to Earth...so yes I can see you saying it looks washed out.. try a polarizing filter on it and the moon is you want to tone it down.. The size of objects like the ring Nebula and all the galaxies are not going to be all that large ..again in any scope under the same magnifications... Bob G. Post Extras:       hopskipson professor emeritus Reged: 06/24/10 Loc: Queens, New Yawk, Light pollut... Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: Bob Griffiths]       #5358391 - 08/08/12 04:29 PM Edit   Reply   Quote Quick Reply   I'm not sure what you mean by washed out. To me on good seeing nights at a magnification of 200x I can see alot of detail such as the Great Red "pink" Spot and 4 to 6 bands. The bands sometimes have swirls and dark "barges" in them. I haven't looked at Jupiter this summer with it's early morning viewing and all around lousy weather lately so I can't comment on what is visable now. As for DSO's their dim light is spread out over a realitively large area and make them difficult to observe. If you add light pollution or a bright moon phase it becomes a real challenge. From my rooftop I have yet to see the Sombrero. The DSO's I have seen like M13 are just fuzzy patches. It takes a lot of viewing time, averted vision and patience to pick up some details in these objects and there is where the fun comes in this hobby. Hunting them down and trying to tease out as much detail as conditions permit. Enjoy the adventure ! Oh! and welcome to this forum!!!! James Post Extras:       WarmWeatherGuy professor emeritus Reged: 08/27/11 Loc: Orlando, FL 28° N, 81° W Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: startrend12]       #5358443 - 08/08/12 05:00 PM Edit   Reply   Quote Quick Reply   I had a C8 for 15 years before I realized that some nights are better than others for seeing stuff. Some nights are WAY better than other nights. Obviously I didn't use the telescope enough. Also, I only recently found out that $70 eyepieces are WAY better than the cheap eyepieces that come in a kit. For sky transparency and seeing try this web site to find out what to expect near you in the next day or two: http://cleardarksky.com/csk/ Things can be dim because your pupil is small if you live too close to a city. If you drive out to Bryce canyon when there is no Moon you will see much more. Post Extras:       startrend12 newbie Reged: 05/24/12 Loc: N.E. Ohio Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: WarmWeatherGuy]       #5361774 - 08/10/12 01:50 PM Edit   Reply   Quote Quick Reply   Thank you all. Bob - I didn't check how close it was, but I guess you are right about the Jupiter - it might be too bright now to pickup the details. James - I used my Meade 8-24mm Zoom to increase the magnification all they way upto 12 or even close to 9 but still couldn't see all the details you mentioned. I guess like Bob said it might be too bright now? WarmWeatherGuy(Steve?) - I totally agree about the dark skies and better optics. Also, thanks for the web site reference. Your photos look really cool, and all of you have great gear! Can you guys please suggest any good medium-price-range eyepieces (not the high-end ones like TVs - yet) for 1. planetary observing 2. for DSOs (I did read through various threads on this topic but...). My main interest is in DSOs but I am starting with planets to get my kids interested. Thanks, SCS Post Extras:       WarmWeatherGuy professor emeritus Reged: 08/27/11 Loc: Orlando, FL 28° N, 81° W Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: startrend12]       #5362034 - 08/10/12 04:20 PM Edit   Reply   Quote Quick Reply   My favorite eyepieces are the Celestron X-Cel LX series. I would start with the 12mm one. http://www.celestron.com/astronomy/accessories/eyepieces/celestron-x-cel-lx-12-mm-eyepiece.html You can find them for $65 with free shipping right now. Post Extras:       engchris super member Reged: 05/17/12 Loc: Florida Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: WarmWeatherGuy]       #5363141 - 08/11/12 10:46 AM Edit   Reply   Quote Quick Reply   Have you allowed your scope to "cool down" before viewing? I have an 8SE also and have been able to view Jupiter a couple of times in the early morning hours. Yes, it can seem a bit washed out but I was still able to easily make out several cloud belts and the red spot. I actually found that contrast improved as the sun began to rise. Not what I was expecting but I suppose the sky becoming brighter and the planet becoming dimmer somehow improved the view. Post Extras:       Midnight Dan Postmaster Reged: 01/23/08 Loc: Hilton, NY, Yellow Zone (Bortl... Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: engchris]       #5363420 - 08/11/12 02:22 PM Edit   Reply   Quote Quick Reply   Hi SCS: The Baader Hyperions are a great set of eyepieces that hit the sweet spot of excellent quality and reasonable price. They go for about $120 each. They have a nice wide 68° field of view, a comfortable viewing distance of 20mm eye relief, and are designed to nearly eliminate blackouts and kidney-beaning so they're easy to view through for long periods: http://www.alpineastro.com/Eyepieces_Accessories/Eyepieces_Accessories.htm#hyperion If that's still too steep, I recommend the Orion Expanse ... or rather the Agena Astro version of the same eyepieces which are $37-$40 each (as opposed to Orion's $65 each). These eyepieces are very similar to the Hyperions in most of their aspects, except they experience blackouts and kidney-beaning much more easily. But for the price, they are a real bargain! You can get the whole set for about the same price as one Hyperion: http://agenaastro.com/agena-1-25-ewa-eyepiece-set.html?SID=caum0evh3sf2uruc07tvrht5c5 -Dan Post Extras:       hamdul super member Reged: 06/23/09 Loc: Litchfield NH, USA Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: Midnight Dan]       #5363535 - 08/11/12 03:49 PM Edit   Reply   Quote Quick Reply   Dan, I've been into amateur Astronomy for the past 30 or so years but the terms relating to eyepieces "Blackout" and "Kidney beaning" are new to me. Pray tell what are they? Fred Post Extras:       brianb11213 Postmaster Reged: 02/25/09 Loc: 55.215N 6.554W Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: hamdul]       #5363589 - 08/11/12 04:40 PM Edit   Reply   Quote Quick Reply   Quote: I've been into amateur Astronomy for the past 30 or so years but the terms relating to eyepieces "Blackout" and "Kidney beaning" are new to me. Pray tell what are they? With some eyepieces - especially long focus ones with long eye relief and consequently very large eye-facing lenses - it can be hard to get your eye in the right place to see the whole field of view and have the eye pupil coincident with the "exit pupil" of the telescope, which is the virtual image of the objective projected outside the scope by the lenses in the eyepiece. Sometimes you see nothing (a blackout), sometimes a part of the field is visible but there's a hole in the field (kidney beaning). Kidney beaning actually only afflicts reflectors as the culprit is the virtual image of the silhouette of the secondary mirror. Eyepieces which are sensitive to these phenomena are usually but not always provided with some sort of adjustable eye guard which helps you to get your eye into the right place, once it's been set properly. Post Extras:       John Laidlaw member Reged: 09/16/08 Loc: Hales Corners, WI USA Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: brianb11213]       #5363626 - 08/11/12 05:20 PM Edit   Reply   Quote Quick Reply   Might I add this with regard to very bright planets? If the image appears washed out, try increasing your magnification - this will spread the light over a larger apparent area, making it appear slightly dimmer. The best magnification will depend on your local seeing conditions and transparency, so experimentation will be key. And, as others have mentioned, practice is essential to learn how to see the details . Post Extras:       WarmWeatherGuy professor emeritus Reged: 08/27/11 Loc: Orlando, FL 28° N, 81° W Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: John Laidlaw]       #5363649 - 08/11/12 05:34 PM Edit   Reply   Quote Quick Reply   SCS, If by washed out you mean you don't see colors then it will always be "washed out." When people say they saw the Great Red Spot on Jupiter they don't mean that it actually looked red. If you are near a forest fire you might see some color as the air is making it that way. The color you see in the pictures is not what you see in the eyepiece. In the eyepiece everything is pretty much monochrome. From what I hear you CAN see color in nebulae if you have a 20 inch (diameter) telescope. Does anyone know if the red spot on Jupiter actually looks red by using a larger telescope? If so, how big? Post Extras:       brianb11213 Postmaster Reged: 02/25/09 Loc: 55.215N 6.554W Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: WarmWeatherGuy]       #5363687 - 08/11/12 05:54 PM Edit   Reply   Quote Quick Reply   Quote: Does anyone know if the red spot on Jupiter actually looks red by using a larger telescope? If so, how big? The contrast & colour of the GRS vary quite a lot with atmospheric conditions on Jupiter, at the moment it's fairly subdued. The colours on most planets are pretty subdued (the exception is the orange/red prevalent on Mars), you'll see more if you use a larger telescope with a relatively lower magnification as the eye sees tonal & colour contrasts much more easily when there's a sharp gradient rather than two patches of slightly different tone/colour some distance apart. I find the best magnification for planets generally is between 20x and 30x for each inch of aperture. Quite often the atmosphere isn't steady enough to allow even that much to be used, if your scope is more than a very few inches in aperture. The more you look, the more subtle colour you'll see. I see subdued orangey reds, blues and greens on Jupiter just about every time I look at it with any scope over about 6 inches in aperture - though I've never seen the GRS as "brick red", at its best it's more sort of a basketball orange to me. As others have said, if there is too much contrast between the planet and the dark sky background, this makes it harder to see detail and colour on the plant. I find the best solution is to view in twilight (or even full daylight, which works well for Mars, Venus & Mercury): if I'm viewing planets at night I always use a filter to reduce the glare. I find that a neutral density filter of the right strength is preferable to variable polarisers, as there's less scatter & they're less fiddly to use. I also use coloured filters a lot with planets, these can help bring out subtle details which the eye can't see "straight" but do of course make the planet's colour look very unnatural. Edited by brianb11213 (08/11/12 05:55 PM) Post Extras:       WarmWeatherGuy professor emeritus Reged: 08/27/11 Loc: Orlando, FL 28° N, 81° W Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: brianb11213]       #5363697 - 08/11/12 05:59 PM Edit   Reply   Quote Quick Reply   Thanks for that. I will look at Jupiter in the daytime. I always figured it would look more washed out because the Moon looks more washed out in the daytime. The problem may be due to my location in Florida where we have lots of humidity. Post Extras:       Midnight Dan Postmaster Reged: 01/23/08 Loc: Hilton, NY, Yellow Zone (Bortl... Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: hamdul]       #5363970 - 08/11/12 09:48 PM Edit   Reply   Quote Quick Reply   Quote: Dan, I've been into amateur Astronomy for the past 30 or so years but the terms relating to eyepieces "Blackout" and "Kidney beaning" are new to me. Pray tell what are they? Fred Brian gave a good explanation. But to add a little ... the problem is that each eyepiece has a "perfect" viewing location. This is the distance, and centering where your eye must be to see the view. If your eye moves some distance from that perfect location, you will lose the view. In some cases, it seems to go black all of a sudden - blackouts. In other cases, you can see a kidney-bean shaped dark area at one side of the view. Some eyepieces, like the Hyperions, are designed with a fairly large tolerance around that perfect location. Your eye can move quite a bit before you lose the view. And when you do lose it, you see it slide out of view rather than instantly blacking out, so you can easily adjust your position and get it back. It makes viewing much more comfortable because you don't have to be so precise about where you hold your head. With other eyepieces, often less expensive designs, the viewing zone is quite small and it requires you to hold your head in just the right location or the view blacks out. This can be frustrating and make viewing less comfortable. As Brian says, using the eyecup as a positioning aid helps with getting the right distance. -Dan Post Extras:       M16SEAL member Reged: 04/04/12 Loc: Riyadh,Saudi Arabia Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: Midnight Dan]       #5364474 - 08/12/12 09:42 AM Edit   Reply   Quote Quick Reply   In best weather condition I can see with 7mm Celestron Luminos (x290) the following : Satrun : you can see the orange line on atmosphere & Cassini division become visible in the rings Jupiter : you can see easily atmosphere bands Mars : small red disk Uranus : you can see small green disk Neptune : you can see tiny blue disk Mercury : orange-yellow small disk Post Extras:       azure1961p Postmaster Reged: 01/17/09 Loc: USA Re: NexStar 8SE - Visible sizes of planets and DSOs [Re: M16SEAL]       #5364908 - 08/12/12 03:21 PM Edit   Reply   Quote Quick Reply   Figure 81x is really really low. I dont even go that low on my 70mm refractor for planets. Typically, planetary observation is 150x to 250x. Large aperture and or steady skys on the smaller targets like mars and neptune can benefit from up to 400x or more. Galaxies will appear larger than any planet with the exception of the smallest galaxies that are either some 300 million lightyears away and are averege or closer in but small regradless. Typical messier galaxies anyway are going to appear far larger in scale than jupiter. M31 for example wont even begin to fit at 80x. Figure on 200x-250x as a rough averege of common working mags for planets and moon. Deepsky is typically, 50x to 200x but exceptions abound. Pete Post Extras:       Pages: 1

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