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PEMS

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Everything posted by PEMS

  1. If possible add your location at least as a town, that way people can suggest a club that you may be able to visit. Unfortunately a beginners scope will be every possible type of scope. Usually they are what the person making the recommendation has. Consider a beginner scope as a first introduction and little more. So purchase something easy simple and inexpensive. In effect something that you will move on from in about 6 months or a year. Learn what to do now, have the summer and then after the clocks change again next September maybe think of an upgrade. Few will suggest a small achro, but a simple 80mm will show you a lot and they are easy. The other plus is you can get a front solar filter, or make your own, and go looking at the sun. A film filter is termed "White light" so will basically only show sunspots - no surface structure or flares. However it adds an option to viewing. Astronomy could be standing outside on a warm sunny summers day doing some solar observing. And a small refractor enables that. Another possible advantage of an 80mm achro is that they can just be handled by the Skywatcher Az GTi mount. So you can buy the scope and an inexpensive mount now, go viewing at night sky and sun (with filtering) and later buy the Az GTi goto mount and have a small easily portable goto mount and scope. So one may not be the biggest bu they have a fair amount of expansion options and diversity. The EQ2 mount is not a good mount, I believe it has no option for a polar scope so polar alignment is difficult. If the mount is Equitorial then really it must provide for polar alignment. Without knowing where you are Clubs: http://www.astronomyclubs.co.uk/Clubs/Counties.aspx If you are close to London then in Feb there is Astrofest, means you have to travel there and the entrance cost has to be added in but you can look at equipment. Although I guess most is advanced scopes. Was a show in Kettering last year not sure if that is to be repeated.
  2. As you give Northumberland as a location is Keilder close enough to you as I believe there is some sort of observatory and public interaction there. Likely a good idea to pay them, assuming there is, a visit. Scopes are in basically 3 varieties and each has it's plus points and it's minus points. Easiest is I guess a smallish wide field refractor. Something around f/8 to minimise the chromatic aberration that is present. I think Bresser or ES sell one that is 80mm aperture and 640mm focal length. There are others that are 90mm aperture and 900mm focal length. Would suggest that you have a look and if possible a try of one or two before anything. Also keep in mind that almost immediatly after the scope you will want a couple of eyepieces. And 2 plossls will come to around £60-£70. Also there is this: http://www.astronomyclubs.co.uk/Clubs/Counties.aspx It only lists 2 clubs in Northumberland, and I would expect one of those to be the Keilder one. But if possible have a look and don't rush it.
  3. I suggest that most "maximum magnifications" are almost irrelevant and certainly rarely are what the manufacturers state. They know that people will see 200x maximum on one scope and 300x on another and buy the 300x, oddly even if they are obviously the same scope. I have a small 72ED, Skywatcher. Here is the fun bit: The scope had a "maximum" of 144x, your standard (2x diameter). As thescope is for wide views and at the time the Mercury transit, the maximum does not interest me greatly. Now Skywatcher updated their information and surprise the maximum is now quoted as (3xdiameter), so has become 216x. Same scope, same glass, same paintwork, same alu case. Nothing has changed on the scope but now 50% increase in magnification apparently overnight. So DK what does that mean? I suspect it is marketing, not physics or optics. Many quotes of a maximum are apparently based on the exit pupil and how the eye can function. Some numbers say the eye has an exit pupil limit of 0.5mm and that is a magnification of (2x diameter). But that does not say the scope is capable of that magnification. That just says the eye may be capable of handling it. Have read a statement with the maths that an exit pupil of 1mm is "best", that means a magnification equal to the diameter (mm). Have read another that says the best is a 2mm exit pupil so (diameter/2) - close to Vlaiv's. Many find it good to go with the 1mm idea, it is in the middle and in a way easy. To get 1mm exit pupil you buy an eyepiece equal to the focal ratio, then the magnification delivered is equal to the aperture. I would expect a young eye - childs - to handle a smaller exit pupil better. How old is your eye? What works now could well not work in 8 to 10 years, maybe not so well in 2 years. You can push the magnification "higher", put a 5mm eyepiece in and a 5x barlow and if you do the numbers the magnification is "higher". Very likely utterly useless, but it is higher.
  4. If the scope is 114 I would suggest that you consider magnifications of 80x and 100x, and if you want to try then maybe 120x. The maximum value given is often based on another consideration that of the exit pupil. Then manufacturers quote a magnification that correlates to that exit pupil. The catch is that it does not mean that the scope is realistically capable of the necessary performance, and usually they are not. The focal ratio of your scope is 7.89, closest integer is 8 so use that. An 8mm eyepiece will give around 110x, a 10mm 90x, a 12mm will give 75x, a 15mm 60x. For the initial finding a low power eyepiece of 30mm plossl or the 25mm options in the 60 degree line (X-Cle LX, BST Starguiders, Meade HD). Most viewing will be at the 60x to 80x area, people seem to think that the higher magnifications will dominate, they do not. It is also useful to work out the field of view that an eyepiece will give you. Little use having a 0.5 degree view on a 1 degree object. Presuming you purchase in steps I suggest a wide 30mm or 25mm, and a 12mm. You can later add a 10mm or 8mm in. Barlows are a bit odd. They alter the image size, so you have an image as if it were from a telescope of double the focal length. Another aspect is they are not specifically designed for your or any particular scope, and they are made to a cost, so they will often degrade the image you see. Many people do not therefore use a barlow.
  5. Ultimately imaging is a motorised mount, usually a goto as they seems better or more accurate, and a scope matched to te subject. For Planets an SCT, often with a barlow or powermate, and for DSO's a small fast scrope around the 80mm in refractors or 130mm for reflectors. The one scope that appears to do neither DSO or planetary imaging is a Dobsonian. The dobsonian was developed as a sort of budget reflector for visual use and to funnel the available money into the mirror side. So they are primarily a visual scope and not well suited to imaging. For lunar they work as the setup then is simply an f/5 lens on a DSLR. The lens just happens to be a rather large telescope however it is just an f/5 lens ultimately. And with that 1/50 or 1/200 of a second will get an image. Why buy what is a visual scope for imaging. I have seen people recommend that you have a visual scope and an imaging scope since the 2 requirements are almost different enough that the 2 should be considered separate. A possibly extreme example is the William Optics Redcat, designed for imaging as I believe you cannot put an eyepiece on it, so imaging only, no consideration for visual. It is said the no one scope does it all, but it seems we still talk ourselves into thinking that maybe this one scope will break the rule and do it all.
  6. As was said by Peter use Polaris. For visual that will be adaquate and the Synscan should be able to account for the difference. Do you have a polar scope with the mount. If so then the next task is working out how to perform the polar alignment better with that and Polaris. Polaris is something like 1 degree off of True North. I have seen values of 0.8 degree and 1.2 degrees. Not sure which one it actually is but 1 degree is in the middle.
  7. The 72ED is the scope of the two for imaging. If used for viewing you will need a diagonal and a few eyepieces, you will find 3 will be adaquate to get started. Which ones you purchase is a case of budget mainly. The Skywatcher focuser does have a lot of travel, so can cause a few problems. If you buy a 2" diagonal then it may be impossible to get enough inward travel. A 2" diagonal looks good on it so if you decide on one research the mechanical size of it for the optical path involved. There are low profile diagonals but not sure how low profile they are. For imaging you do not need the diagonal, you attach straight through with a T-ring for the DSLR or whatever attachment is required for an AP camera. Hold off of buying a guide scope. You cannot fully guide with the mount as it does not have a declination motor so there is no way you can control that aspect. Which means is it worth purchasing a guide scope and camera. I would not, however your decision. It seems to be a case that having a guide port makes you think you can guide fully whereas you cannot. So a guide port does not mean you can guide, at least fully. The focuser on the skywatcher 72ED does not feel very solid. You may need to take it apart to understand how it fully operates. Mine I found I just could not adjust correctly until I had taken it apart to see what exactly was happening and then understand it more. Slightly extreme maybe, but it worked, asI now know what is going on. The scope is flexible in that you can add diagonal and eyepiece and view, remove diagonal and add attachments and DSLR and image, you can also add a solar filter or herschel wedge and solar view.
  8. The Desktop/laptop version is separate to the mobile version. The mobile version I bought has rarely been used. Honestly would say less then 5 times in 2 or 3 years, just found it to be poor in comparison. Skysafari is in my experience infinitely better. You will likely find you only need the Plus version of Skysafari. If telescope/mount control is a factor now or in the future then I would again go for Skysafari. They seem to be the one that most manufacturers have talked and developed with.
  9. Possibly a few things to check: Is the location correct, the scopes used to want Longitude then Latitude whereas we talk of Latitude and Longitude. So make sure that 51.5 (51 30) is actually the Latitude and not the Longitude. Longitude would be about -0.5 (-000 30) at an estimate, check the leading zero's as you could end up at 30 degrees West not half a degree West. Date and time is not remembered, you enter it each time and Date is US format, not UK format. If you get it wrong they do not inform you of any error. In location check the timezone, they can default to Western Pacific Timezone which is UTC -8 They will need setting up at the start and Level and North (as it is often termed) is a reasonable choice. Would have expected the manual to have given a requirement but I guess back then they didn't bother as much. From reading others posts I also suggest that you do a reset as that seems useful, even required, to clean out data in the memory that appears to hang around.
  10. Works fine with the 1.25" fitting. Used one for the transit all day. The travel problem is when you fit a 2" diagonal and eyepiece, there is just enough inward travel if you are lucky. I had the adaptor skimmed a bit at a machine shop to gain 2.5mm. However as the 1.25" wedge fitting is smaller it works, the diagonal does not gobble up the path length. Will agree that a bit more travel on the focuser would be nice Having to get 2.5mm removed was a bit extreme I felt and will not I expect suit all eyepieces. If you intend to use a 2" diagonal then expect possible troubles or concerns, or search for a more suitable, as in shorter, diagonal.
  11. They are an improvement but in their basic form still "white". For a step up you need the continium filter. And they add to the cost. Have used an ED80 with a Herschel Wedge and will say very good experience. They are a solid lump so no concernes about damage to the film filters. Have read of the Lacetera being at the Brewster angle, not sure what extra that adds. Bought the TS wedge for the transit and after some confusion it is fine. It comes with a continium filter AND they have an ND3 filter stacked with the continium. Slight problem is no real mention of the ND3 so I bought a seperate ND3 then found 2 days before the transit that I did not require it. Works well as it comes and I suppose I can now swap the TS combination for a simple and single ND3, so have White, not Green. I also purchased a UV/IR cut, bit additional safety but never fitted it on the day. Suppose the answer would be you do not "need" one, but they are a very nice addition to the equipment armoury. You will use it and I would expect use it more.
  12. Scope sounds a good choice and you have a reason for the moon filter. You have at least put some thought into it. I would agree that the eyepiece kit is probably not that great a decision. My opinion is that 2 well thought out individual eyepieces are better. So if not ordered I would suggest you hold off of that at this time. Would suggest as a tip that you add your town or county to your information. In general knowing approximately where a person is helps. Runs into the state that if close by to myself you are welcome to try an eyepiece or two. Very likely many miles away but never know for sure. Take time to set up finder and scope, they do not just fit right and need setting. Other bits are learn the basic constellations and therefore the main stars. A suggestion of try Almaak in Andromeda means you have to have some idea of Andromeda at least. Start on easy targets, again needs a little thought applied. Oddly M31 the Andromeda Galaxy may not be easy owing to its size. You need quite low magnification to get it all in a single view. But everyone tries for it. Hope the eyes make a full and improved recovery.
  13. A friend of mine has one of these and they had to make a small converter to go from a now normal circular power plug to the PP3 that the ETX uses. From what they have said it is easy but a little bit of a catch in the way the wiring goes. Think they bought the 2 bits reuired from Maplin, who no longer exist. So a bit of a problem I expect. Also they work well on 12v, they use a lithium 12v battery rested on the base under the tube. I will ask them the details. Where in Southern England are you?
  14. Useful post, I bought one of the TS solar wedges a couple of months back and never realised there is an ND3 in effect built in with the continium, so just bought a separate ND3 to use under the clouds Monday. Don't need the second ND3 now, bit unimpressed as everything indicated no ND3. Just separated the TS filter and yes there is an ND3, will say I did wonder why the continium appeared rather dark, now I know. Have to remove the ND3 I bought from the internals of the wedge as I would expect ND6 to be a little on the dim side. That was money I didn't need to spend. Also need to clean the TS filter now. Suppose like Neil I can have white or green.
  15. I have found that you learn the sky with either, there is no "One or the other". A lot will be a case of what do you want to do. If you want to go to an object and see them then move on after a while to another then the goto. If you want to scan around the sky a bit and see what you bump into then get a manual one. The goto would mean you have to have an idea of what you would want to go look at to occupy an evening of observing. In effect you have some homework of making a short list up. They are useful as you can just let the scope track the target for 10-20 minutes as you need do little once the object is found. A goto is not automatic. There is a fair bit that you need to do before it will do its bit of going to a selected object. Most is actually manual strangely. A scope like a dobsonian needs no real setup and if you ignore cool down - think everyone really does - you can be viewing in minutes or less. With a dobsonian you can sort of wander through a constellation and see what pops into view. Biggest decision will be Astrophotography or not. A dobsonian is not the scope for any real imaging. So decide that aspect initially. Or decide to have a visual dobsonian and a separate imaging rig. A 6" dobsinian is something for you to use while the imaging rig is collecting an hours worth of exposures. But the idea of "Learn or Goto" is somewhat invalid. Bet no-one has been at a star party where the owner of a goto has asked which star is which for them to set their scope up. Everyone I have met with a goto knows all the stars, where the targets are and whether to scope has gone to the right area of sky for the requested target - they know the sky.
  16. Check Lat and Long values. The mount does if I recall have the input as Long then Lat, whereas we talk of Lat and Long and very often input therefore the 2 values the wrong way round. The other is to check the Date, it is in US format of mm/dd/yy. However a recent date would mean a month greater the 12 which it should not accept. They do not say Error, they just sut there displaying the value that was entered but do nothing with it. So unless you see it the date may revert back to whatever the system defaults to. I guess that you have set a custom location and so have set the timezone to UTC 0, I think it is entered as 0. The mount may default to a US timezone. And if you have picked a location from the offered list then set a custom location. Means you cannot pick say Birmingham, and get Birmingham Alabama and not Birmingham UK.
  17. Maybe we should not automatically side with the person with the dome. They could want the neighbour to keep their lights down and then be out at the early hours of the morning rotating a noisy dome and disturbing people. Would expect that dome to produce significant noise when rotated from target to target. The "evil" neighbour may just have become fed up of it and complained to the council through having an inconsiderate astronomy observer living next to him. The astronomy guy has not bothered to ask or enquire about the need for planning permission. Did he talk it over with the neighbour or just go ahead regardless? There may be another side to the story.
  18. I believe the Tracers are LiFePO and they will start initially at 12 volts but drop rapidly to around 11.5v. Strange the lesser cost Li Ion batteries start a bit higher in voltage and if memory is right do not drop quite as much, they could run most of the time at around 11.8 volts. Flashing light on the mount is under voltage so tracking may be also be a little low, which is no good. Also it will give up at some time and part way through a session is not what you want. Yes they are 12 volts, but not for very long, probably 5 minutes of initial life when fully charged and maybe only when new. For that you would really need one that is rated at around 13 volts, maybe a bit more. Check out a motor cycle Lithium Battery as they are rated at 13.2v. They only come is small capacities. 4Ah or 5Ah being common before the cost escalates. LiFePO are good as they maintain charge longer, you do not have to charge them as often, you can leave them longer. But if you use one and then recharge and either use the equipment regularily or check the charge at intervals of 2 or 3 months they would seem to have little advantage.
  19. If you have the Pro version and it is for Eq then the scope should I think be mounted on the Right Hand Side. That allows for a counter weight bar to be added and that for Eq operation forces the scope on the right to operate correct. I would however then question the mount firmware version. So possibly the app is Eq, the motor or setup is Left Hand Side/Alt-Az. Question is does the Pro App need newer Firmware on the mount. Can App and Motor Firmware get out of step. The App on mine is updated automatically but never updated the mount firmware. When mine arrived I do recall a few options that you had to select and set. May be worth looking through those again as sometimes a new App version goes off to some default settings. Also which side when set up are you placing the scope on, was asked previously. What device are you running the App on? Assume that it is GPS for data and the other bits?
  20. As Peter says reads that you are entering the minutes bit as a decimal value and NN.63 so trying 63 minutes for example is invalid. That field can be no larger the 59. For completeness the minutes would be Minutes = (0.63*60) then you enter that as the minute value field. However on Google Brooksville has the decimal value below Something.5 so even if that is the problem values as per Google should enter. However up around the danger area and a different map may give a value just a bit too big. Google says: Long 82 28' West, and Latitude 28 31' North, minute values rounded a bit. There is no message displayed to say Invalid Value. The handset just sits there until you realise the problem and put it right.
  21. My opinion is find a club and see what is around, then decide. Which bit of the UK or world are you. All scopes have poor aspects, you basically have to give up something. You have aperture and usually a reasonably wide view, but do not have the goto ability nor the tracking. One of the SE strains of scope will give you the goto and the tracking but you will lose the wide views and some aperture, setting up can then be not so straight forward. My scope for here is a small Az GTi and a Skywatcher 72ED, not going to go big was a decision I made. Much less aperture but I find it an easy to use scope. I read that the mount will take an 80ED, but no more. You need to determine the positives and the negatives of any scope and system. If my little small aperture 72ED gets things in view I would consider it better then anything significantly bigger that fails. Also just purchased a Herschel Wedge for solar viewing. Small scope maybe, but usable and flexible.
  22. You must have clutches. You release the clutches when you manually move the scope then you tighten them for the motors and gears to engage to drive the main scope. Guess that is the problem therefore. You need to find and set the clutches as appropriate. Since you can move the scope at present to center the alignment stars it would read that the clutches are more or less off and so the motors and gears are not driving the OTA correctly. Slight slippage.
  23. Entirely personal but I would go with the better quality 80 ED and sacrifice the aperture. An 80mm is also often considered the best all round aperture refractor to "do anything" , at least within reason. It can go on a basic mount, or a small goto, do astrophotography, add a solar filter and observe the sun. Moon and most planets will show a fair detail. Althogh as I have read there are not really that many observable planets. Jupiter and Saturn are OK but Mars seems to cause problems. I would say that abything the 80ED struggles with the 120 ST would struggle with. So the better quality is my choice.
  24. Friend of mine looked into options a couple of years back, from memory: As best I recall look for UCLAN they have a distance learning degree and maybe lesser certificates. Something says they also operated under the name of astronomy.ac.uk. So search for that also, may be a more direct source of information. Another possible was Birkbeck College, however less knowledge on their offering. OU has or had an OpenLearn scheme. Small free courses and I would think you selected a range to do but they were not a recognised final qualification as in BSc type. There was also at time mention of Coursera who offered again small courses. Think they were free also. From the previous look in to this I had the impression that in the UK you had A'Levels then Degree and not a lot between to build up over time. Think that is what put my friend off. It was small courses for no great recognition or a Degree.
  25. A local craft shop will have sheets of red acatate or acrylic that you can use. One I visited recently had a few colours in stock, they did have a red. As a easy to remove cover I would say try taping one side with something like sellotape, I have a roll of tape that is notated as Invisible. Seems a nice flexible strip of tape. Tape one side or the top and fold or flip the sheet as required.
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