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Buzzard75

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About Buzzard75

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    Nebula

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    New Bern, NC
  1. Which eyepiece do you REALLY use most?

    Either my ES82 14mm or my TV Delos 10mm. The only other eyepiece I own is a cheap Orion 28mm that isn't good for much other than locating objects. Still working on filling out my eyepiece case. Think I have room for one or two more.
  2. Skyscan goto

    In decimal format, anything west of the meridian (from the UK, across North and South America to the international dateline), longitude is expressed as a negative value. South of the equator latitude is expressed as a negative. In your case, your longitude is -1.29 and becomes 1.29W. In order to convert the decimal, you need to know that latitude and longitude are expressed in degrees(deg), minutes(') and seconds("). There are 60 minutes(') in each degree and 60 seconds(") in each minute('), thus there are 3600 seconds(") in every degree. For every tenth (0.1) of a degree, you can multiply by 6' (60'/10=6'). For every one-hundreth (0.01) of a degree, you can multiply by 36" (3600"/100=36"). Your longitude is 1.29W. Working with the tenths, 0.2*6'=12'. Working with the hundreths, 0.09*36"=324". Now, in 324" there are actually 5' and 24" (324/6=5 remainder 24) so take the 5' and add it to your previous (12') and you get 17'. So your real longitude expressed in degress, minutes, and seconds is 1deg17'24"W. That's the long way. The short way is to approximate per ronin's suggestion. Also, Stellarium and Star Walk 2 provide your GPS coordinates. Stellarium gives it to you in both degrees+minutes+seconds as well as decimal and Star Walk gives it to you in deg+min+sec. Your phone's default clock app should also be able to tell you what time it is down to the second, which is close enough for SynScan.
  3. I probably would have thought more about where I possibly wanted to go in the future with the hobby. I underestimated the itch. When I first started, I wanted something that would give me large, looming views of Jupiter and Saturn as well as DSO's, mostly nebulae and galaxies. That led me down the path of finding a scope for visual observing and, since I was on a budget, getting the most for my money. It's hard to beat the light capturing capability of a dob for the money so that's the direction I went. The problem with dobs is, they can be quite large and may not be easily portable depending on how large they actually are. I've gotten it out several times in the last few months, but it's kind of a hassle and takes me an hour to lug everything outside to my spot and get it all set up. Then it takes another hour to tear it all down and get it put away properly. Which is fine if I'm going to be right outside my house for a few hours. Not so good when I have to drive an additional two hours round trip to a dark site only to get put out by cloud cover. Now that I've been observing for a while though, I've taken an interest in astrophotography, but don't have the setup for it. It can be done with a dob, it's just not made for it and the results will never be as good as something on an EQ mount. So as I said, now I'm wishing I had thought more about where I might want to go in the future with the hobby. I probably would have spent a bit more money and bought something that was more portable that I could do both observing AND photography work with. If I had bought something smaller on a tripod mount that I could leave assembled and just pick it up and take it outside, I'd be more inclined to do that than have to spend two hours hauling assembling, and disassembling the dob. On the flipside though, had I bought something smaller, I wouldn't get some of the views that my dob has been able to provide me. So I guess those are really my recommendations. Think about what you want to do now, what you might want to do in the future, determine if portability is a large concern for you, know what your budget is if you have one, and buy something that fits into all those criteria.
  4. SYNSCAN HANDSET v4 USER MENU

    Doesn't seem there's an option to delete. It appears when you add something new you can specify which number you want it to have in your list and if something already exists in that slot, it just overwrites it.
  5. Theoretical maximum magnification is often quoted as 50x the aperture in inches. The USEFUL maximum is about half that. In your case, 150mm=5.9in, the theoretical maximum is roughly 350x, but the useful maximum is only 175x. With a focal length of 1800mm, you should look for an eyepiece or a combination of eyepiece and Barlow that will give you this useful maximum or something as close to it as possible, so roughly 10-11mm. You could get a 10mm eyepiece or a 20mm and a 2x Barlow and achieve the same magnification. If you buy the Barlow, then any eyepiece you buy after that would essentially be like buying two eyepieces. You also don't want to go too far below a 1mm exit pupil. The lower you go the more uncomfortable the viewing can be and you may begin to start focusing on floaters and things in your eye rather than your object. Take your eyepiece focal length and divide by your focal ratio to get your exit pupil. Your focal ratio is 1800/150=12. So 10mm/12=.833mm. On the other end of the spectrum, I start looking at exit pupil sizes more closely because I have a Newtonian with an obstruction in the center of the aperture. Anything that will give you an exit pupil larger than 7mm will start to show a darkening in the center of the image if there is a secondary mirror obstructing the aperture. Also, the human eye isn't capable of dilating much more than 7mm. Some people aren't even capable of that and it gets worse as we get older. With a 7mm exit pupil and an f/12 scope, the longest focal length eyepiece you'd want is 84mm. Good luck finding one that long. Even if you did, it'd probably be ridiculously large and expensive. I'd say 50x is probably as low as you'd want to go, so a 36mm eyepiece would probably do you well. And if you bought the 2x Barlow, you'd also essentially have an 18mm eyepiece as well. As for what goes in between, anything that really tickles your fancy. Tele Vue, Explore Scientific, Plossls, Naglers, etc., etc. Each manufacture and type of eyepiece will have pros and cons and it's really up to you to decide what you really like about each brand and type. You also have to decide what's in your budget as each manufacture and type will vary greatly in price.
  6. SGL App???

    I use the Clear Outside app, but unfortunately find it's not extremely accurate in forcasting cloud cover. Several nights I've missed out because it forecast 90+% cloud cover so I didn't even bother. It ended up clearing off to something I would estimate as being less than 25%, which is more than acceptable viewing conditions in my book, but by that time it was too late to haul all my gear out.
  7. Eyepieces for a 12inch dobsonian

    Welcome, Div! I'm not sure if you have the one with the IntelliScope system (XX12i) or the GoTo system (XX12g), but they are essentially the same scope. I personally have the XX12g. I have a 28mm Orion DeepView eyepiece that came with the scope, a 14mm Explore Scientific 82deg eyepiece, a 10mm Tele Vue Delos, and a 2x Orion 4-element Barlow. Bottom Line Up Front: To get down to the crux of the discussion. We have the exact same telescope. However, what works for me and what works for you may actually be two entirely different things because of our personal preferences and our intentions of use. Likewise, what works well in one telescope, may not work very well in another, such as the difference between a 12" and a 4". Not knowing what that 4" telescope is, it's hard to tell you what you should be seeing compared to a 12" dob other than everything will be smaller and dimmer in the 4" when using the same eyepiece. Typically for planetary viewing though, you're going to want the shortest focal length you can get to bring out the most detail while not enhancing distortions from the atmosphere (more on that below). Some evenings I can push my magnification all the way up to 300x using the 10mm and the 2x Barlow. Other nights I'm only able to get it to 214x using the 14mm and the 2x Barlow. At 214x I can get Jupiter and all four of the Gallilean moons in without any issues and I can make out most of the cloud bands. If the seeing conditions are optimal and I can push it to 300x, I may start to lose Callisto depending on where it is in its orbit, but I can make out all of the cloud bands and even see the Great Red Spot if it's facing us. When looking at Saturn, I can see the Cassini Division. Using the 10mm and a 2x Barlow I essentially have a 5mm eyepiece. If you're not starting to see this when using your 6mm eyepiece on your 12" dob and it looks exactly the same in your 4", then there's either something wrong with your eyepiece, the telescope, or you're not looking at what you think you're looking at. Getting to the meat and potatoes of it. Be prepared, this is somewhat of a lengthy post and some of it will probably be information you already know. Since I have the same scope though, I want you to understand how I made my decisions as to which eyepieces to purchase and all my logic behind them. Finding the right combination of eyepiece and telescope is somewhat of a trial and error. That being said, there are some general guidelines that can be applied upfront to help steer you towards the right focal lengths. For instance, the rule of thumb for theoretical maximum useful magnification of a telescope is typically defined as 50X the aperture in inches. In our case, this results in a magnification of 600x (50x12). This is under ABSOLUTELY PERFECT seeing conditions. Given all of the atmospheric interferences we have to deal with (humidity, air turbulence, clouds, dust in the air, etc.), it's a very rare thing that we can even push magnification beyond 200-300x depending on the quality of the optics in the scope and the eyepiece. Not only are you magnifying the object you're trying to view, but you're also magnifying all those disturbances between you and it. It can make for a very hazy image and it may appear to shimmer. This shimmer is actually the atmosphere you're seeing. So let's assume 300x is our maximum. I'm sure you're already aware, but if you take the focal length of your telescope and divide it by the focal length of your eyepiece, you'll find your working magnification. Consequently, if you take your focal length of your telescope (1500mm) and divide by your maximum magnification (300x), you'll find the shortest focal length eyepiece you'll probably want to use (5mm). The other thing you need to worry about when getting to the short focal lengths is exit pupil. To find your exit pupil, you take your the focal length of your eyepiece and divide by the focal ratio of the telescope. The focal ratio of the telescope is defined as the focal length divided by the aperture (1500mm/305mm = 4.9 or commonly noted as f/4.9). The exit pupil of a 5mm eyepiece would be 1.02mm (5/4.9). This is a perfectly acceptable exit pupil. You can go smaller, but anything smaller than 0.5mm will be like looking through a pinhole. Some people even begin to see floaters in their eyes and begin to experience discomfort as the exit pupil gets smaller. It should also be noted that a smaller exit pupil will also appear dimmer when viewing nebulas and galaxies than a larger exit pupil. Small exit pupil sizes are something that is a personal preference based on what you find comfortable and acceptable. Moving on to the other end of the spectrum, the longer focal length eyepieces, one of the biggest things to concern yourself with is actually the exit pupil again. Only this time we're talking about large exit pupils. The human eye is only capable of dilating so large. Some people's pupils can get wider like owl eyes, but as we age, they typically can't dilate as much. With refractors there really is no limit to how large an exit pupil can get before developing any negative impacts. With reflectors like ours however, we have a secondary mirror in the path of our vision. If the exit pupil gets too large, the center of the image will actually begin to dim due to the obstruction of the secondary mirror. I personally use 7mm as my guideline, but yours may be different and you may be comfortable with a larger exit pupil. Using this as a guide though, we take the exit pupil and multiply it by the focal ratio, giving us 34.3mm (7x4.9) for a long focal length eyepiece. Now, 34.3 seems like an odd number. I would feel comfortable bumping that up to 35mm. This would also give us a magnification of 42.8x (1500/35). Coincidentally, if you look at the specifications for the telescope from Orion, you'll see that they actually have already defined the lowest useful magnification as 42x. You could have just taken those two numbers and figured out the appropriate focal lengths, but I hope this explanation has provided some more insight into how they achieved those numbers. Conversely, they defined the theoretical maximum magnification as 610x and the highest useful magnification as 300x. So you have a large and a small eyepiece, what do we put in between? Really anything that tickles your fancy, however there's one caveat to that and it's Barlow lenses. You seem to have a wide range of eyepieces and quite a bit of overlap. I personally decided on getting a 2x Barlow so that I could effectively double the number of eyepieces I have rather than having a plethora of individual eyepieces. In the case of a Barlow you want to try and avoid factors and multiples of eyepieces you already own as you can get Barlow lenses in 2, 3, 4, or even 5x. I have three eyepieces, 28, 14, and a 10mm. With the addition of a 2x Barlow, I have essentially doubled the number of eyepieces. I now have the equivalent of a 28, 14, 10, 7, and 5mm. But wait, that's only five not six, you say. You're right. With a 2x Barlow my 28mm is essentially a 14mm eyepiece. I've broken my caveat of factors and multiples, but I don't intend to use the 28mm for much longer and I'll get into why later. I knew the shortest I would ever go would be 5mm. Starting with that and deciding to get a 2x Barlow meant that I could actually get a 10mm eyepiece rather than a 5mm and double the number of eyepieces I had. So every eyepiece I purchase from here on out is like a 2-for-1 sale. On the opposite end of the spectrum, the largest I'll ever go is 35mm. However, I also needed to consider the apparent field of view (AFOV). Some people prefer a narrow field of view while others prefer a wide field of view. Both have pros and cons and a lot of it is personal taste. I personally wanted a wide field for object location and that space walk feeling when looking through the eyepiece. There are some nice 35mm eyepieces out there. However, some of them have a somewhat narrow AFOV (68deg or less) when compared to others. I can actually get a slightly shorter focal length eyepiece (increasing the magnification) with a larger AFOV (cramming more stuff in), and actually have a slightly larger true field of view (AFOV/mag) for that space walk feeling I'm looking for. Right now I have my eye on a an 30mm Explore Scientific 82deg. The magnification is only slightly reduced from the 28mm I already have, but the apparent field of view is greatly increased from 56deg to 82deg. This means that my true field of view goes from 1.04deg to 1.64deg of the night sky. And here's where we get into eyepiece construction. The quality and construction of the eyepiece can play just as big of a part in the quality of the imaging as the combination of the scope and eyepiece focal lengths do. The 28mm eyepiece that came with the scope has a fairly narrow field of view at 56deg, compared to the 82deg of the Explore Scientific and the 72deg of the Tele Vue. It also only has four elements. The Tele Vue has somewhere between 6-8 as does the Explore Scientific. Neither has published how many lenses or what type they are, but these are what they are believed to be. Typically the more lenses, the better the imaging, but that's not always the case. You also have to take into account coatings of lenses, lens groupings, and construction of the actual optical tube they are held in. All of this plays a part in the image quality obtained from the eyepiece and this is where the trial and error I mentioned at the very beginning come into play. Each manufacturer has their own proprietary coatings, lens orientations, and eyepiece manufacturing techniques. They can all have a variety of types of eyepieces that they offer as well. Two eyepieces from two different manufacturers, or even the same manufacturer, with the exact same focal lengths, and the exact same AFOV's may actually provide very different imaging qualities. For example, the 28mm Orion I have is a fine starter eyepiece. But it is absolute junk compared to something from Tele Vue, Baader, Explore Scientific, or even some of Orion's own higher end eyepieces. It is Orion's absolute lowest-end entry level eyepiece. It's not something I use for regular viewing. I only really use it for object location and then switch to my 14mm. This is why I said I was looking for something else. I want something that will still provide me with the object locating capability, yet with better imaging capabilities that I would actually like to use for those larger deep space objects (DSO's). In order to find what works best for you, you may have to try a number of eyepieces. That's not to say that you can't be happy with what you already have. What you have may be perfectly fine, they are just suited for specific situations. Short focal lengths are great for planetary observing while longer focal lengths are great for DSO's. Some of the eyepieces may have better coatings on them that lend themselves to providing better anti-reflective or light scattering properties. I recommend you continue to use what you have, find out which ones you like the most, and determine why. If you have the ability, I'd also recommend you join a local astronomy group and attend a few viewing sessions. These can be great places to meet other knowledgeable people and possibly even try out their eyepieces to see if there's something out there that you like even better than what you have.
  8. According to the documentation, 1-star is only available for equatorial mounts. Alt-Az setups and GoTo dobs can only do 2-star and Brightest Star or do the Easy Tracking mode.
  9. I was actually just looking into this myself. I have the SynScan V4. Per the manual, it has an Easy Tracking Mode. Put the scope in the Home Position (base leveled, scope horizontal and parallel to the ground, pointing true North. Turn it on and let it Initialize. Skip the Alignment and start the tracking function directly and then references Section 5.4 of my manual. And that's where I'm stuck. So it sounds like it's possible even for an Alt-Az mount, but I haven't quite figured it out yet. Edit: AH HA! I got it. You go into the Menu and select Tracking. In there are options for Sidereal Rate, Lunar Rate, and Solar Rate. In this case, solar or lunar would apply fairly well.
  10. ...that's what I want to know. What? This isn't Hamlet and I not Shakespeare, people. This is SCIENCE! With the eclipse coming up, I have a decision to make. I'm heading west for the weekend and I'm debating on taking my dob. It's very much overkill for solar viewing and the eclipse, but I thought if I had some good clear skies at night I might use it then as well. It's just going to be fairly light polluted for night time viewing where we'll be staying. For solar though, I have an off-axis filter, which helps a bit, but the sun is still excrutiatingly bright. I also have a variable polarizing filter that's intended for the moon and blocks up to 40% more light transmission, so that helps some as well. Using both, it's actually not too bad. To top it off though, the weather is showing that it's going to be a bit cloudy and possibly rainy the whole time we're up there. If it's not obvious, I really want to take it, but there's a lot of stuff telling me not to bother. So what would you do in my shoes? Would you lug your 150lb dob setup and all the other stuff that goes along with it nearly 400 miles and over six hours to a fairly light polluted area on the hopes that you may or may not get to use it for either night time or solar viewing? Or would you just leave it at home?
  11. Favourite summer DSO?

    I've only been to a dark site once so it's hard for me to choose a favorite. I was all over the place that night. I was floored the first time I saw the Trifid Nebula, M20. I'd never seen it before and I was actually able to make out its structure even without a filter. I've yet to see the Veil Nebula that everyone regards so highly, but I've also yet to try. I'll add it to my list, but I might have to wait until I get an OIII filter. There are so many other things on my list to view. All that being said, my eye is always drawn back to the Ring Nebula, M57, though so I would have to say that's my current favorite. It's bright enough that I can see from my light polluted backyard and it looks amazing at a dark site. I don't think I've seen enough to declare any one object my favorite though.
  12. Aug states Solar Eclipse

    I would suggest somewhere in the middle of the country, part of Wyoming, Nebraska, Kansas, Missouri, Kentucky or Tennessee. Stay away from the coasts. The west coast and parts of Idaho and Wyoming are dealing with fires and the east coast is under constant threat of thunderstorms this time of year. I'll be heading to South Carolina, not too far from Luna-tic. Hoping for clear weather.
  13. The Case of the Mysterious Telescope

    I did ask Orion. They said they don't maintain a complete inventory of parts and they don't manufacture the EQ-2 anymore. I told them what I needed it for and they actually suggested I buy the AstroView tripod and mount. Yeah, no. Not going to spend $260 on something I'm going to just turn around and donate. Maybe Skywatcher will be more helpful, but I doubt it. I don't weld and I don't know anyone who even has a welder, but I can ask around. It's an option. Shipping from the UK will probably cost more than the parts themselves. I might just have to end up giving it to them as is. Thanks for all the info and the ideas.
  14. The Case of the Mysterious Telescope

    Thanks! Yeah, not sure I really want to put an arm and a leg into it and pay for that shipping. I don't mind putting a little bit of money into it so the club or someone else doesn't have to. I reached out to both Orion and Sky-Watcher who both have distribution in the US to see if I can work something out. I wouldn't be fussed about dropping $30-40 into it, but I certainly don't want to basically pay for an entire mount.
  15. The Case of the Mysterious Telescope

    Yeah, it's really the piece that the leg attaches to. If I could get a replacement part and a new accessory tray, I'd be set. I wouldn't even know where to get the replacement parts though.
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