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Showing content with the highest reputation on 20/04/13 in all areas

  1. 9 points
    I did a automated session with CCDAutoPilot on M101 last night with strong wind gusts (5 Beaufort), severe light-pollution and Moon. I managed to track with 0.29" peak-to-peak with 5 Beaufort wind! Normally I can achieve 0.1" peak-to-peak. With guiding of course. More details on my website. 9x 600s Luminance 1x1 9x 600s RGB 1x1 Automated with CCDAutoPilot, Maxim DL and FocusMax.
  2. 3 points
    Hi, I had around 90 minutes of solar Ha this morning and found this nice little filiprom (filament and Prominance) in the lower left hand corner. This was taken with a Lunt 60 Double Stack and DMK41. I am still processing the other images and will post later. Robin And in negative
  3. 2 points
    Seeing went from the worst I've ever seen to reasonable for a 20 min window. Combined dfk colour and qhy IR pass captures between 12.33 and 12.50am. Colour QHY5L-ll cam came yesterday but had major colour balance issues so need to get some advice using that. QHY IR+ DFK colour: DFK colour: Another combo version : DFK colour run through pipp : Here is an image with the colour QHY the colour balance is horrid I'm clearly doing something wrong (wavelets no other processing, seeing was much worse on this)
  4. 2 points
    By the time I got to Saturn about 11.45pm the seeing was miserable and I decided to only bother with IR pass filter on SPC900/618 chip. Taken at F40, C9.25, AS2, R6, 1.5 drizzle reduced to 50%. Still always nice to get something to justify standing out in the cold, almost sober, late on a Friday night
  5. 2 points
    No, you need two to make a binocular. For a pair of binoculars you need four. I'll get my coat.... On the batphone, so expect typos...
  6. 2 points
    i was also looking at replacing my 10mm with an 8. ive heard good things about the bst's. but i was wondeing what people think of the ed's. i was looking at these, http://www.ebay.co.uk/itm/370782587867?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
  7. 1 point
    Since I've had my SW130p Alt Az Goto scope for almost a year now I thought I would write a little something for anyone thinking about a similar GOTO scope as their first step into astronomy. My thought process when I got the scope was probably fairly typical. I figured that the GoTo system would allow me to find my way around the sky fairly quickly without having to learn every inch of the night sky manually. I also had limited time for observing and thought that this scope would get me going much quicker from the start. Neither of these things turned out to be true. So before you make the choice to Goto or not to Goto here are a few things they don't tell you in the manual. 1. Mount set up. Stability is the key here - don't fully extend the legs (keep the scope low if you can. It must be level - I can't overstress this - buy a spirit level and triple check that it is level - with the scope on and balanced. Rotate the scope all the way round and check that it stays level. 2. Handset set up. Entering the LAT and LONG - These coordinates have to be correct. Also make sure you are not using decimal coordinates found on some websites. Get the correct ones for your location - Don't enter them the wrong way round - Most sites give you North then West buy the SynScan wants West then North (made that mistake a few times!) Get the right timezone. +00.00 for the UK Be accurate when entering the time. Daylight Savings - can't tell you how many times this confused me - for clarity this means British Summer Time (when the clocks go forward) so for right now the answer is NO. Then you can begin alignment (I use 2 star align) This is where the fun starts. The handset will list possible alignment stars. At this point you will realize that you really don't know enough about the night sky and may not be able to locate Mizar or Alioth without a star chart. Also the handset assumes you have an uninterrupted 360 degree view. So when the Handset suggest Dubhe (front tip of The Plough) and I'm at home on the patio - that is behind my house and obscured from view. So then I had to use Stellarium on my laptop or starwalk on my iPhone to work out which star is which. Having located a star which I can see I then line up the red-dot finder on it and then get it centred in the EP - It will inevitably then suggest a second star which is either obscured by houses or trees or list some that I just don't know. Suffice it to say that this takes some time. If it takes too long between the first and second star alignment things are not great form there on in. So Quick set up? - NO not at all Easy to find my way around with no knowledge of the sky> - NOPE Don't get me wrong - when it is all set up and working it is great. (providing you don't get overexcited and accidentally kick one of the tripod legs causing you to have to do the whole alignment again!) But I have only been able to get up and running quickly by being very prepared in terms of having the right coordinates before I go anywhere with the scope and being very careful when entering data into the handset. In addition I have had to learn the night sky so as to be able to locate various stars for alignment. So I bought a good star atlas and also a copy of Turn Left at Orion. Knowing the night sky really does make things easier. Other issues. As I said - it assumes a 360 degree clear view. So if you go on the Deep Sky Tour and choose Andromeda - it might still be behind a tree or house. It also does not know what scope you are using. So some of the DSO's it is listing may be well beyond the resolving power of your scope - The 130p is great but some targets are beyond its power. Batteries - Don't use rechargables - the power output drains and the scope goes out of alignment. Invest in some kind of PowerTank if you want a full night's observing. Try and find a 360ish clear viewing point if you can - it makes a world of difference. Plan your observing session - I will use Stellarium (free to download for Mac or PC) to plan the night's session - choosing targets and times before hand. I will use a star chart to make sure I know where the scope should be pointing. In many ways (bad weather aside) it has been great getting to know this scope and it certainly forced me to learn the night sky. If I could have a "Do over" I would have bought an 8" Dobsonian but there is still a lot to recommend the 130p Goto. My next purchase will be a SW250px Dob - but without learning the night sky first I would be as out of my depth with that as I was with the 130p. Hope that helps someone in making the right decision on a scope - or if you bought a Goto scope maybe it will be useful to you. Clear Skies - Nigel
  8. 1 point
    Going to try my hand at Uber-geekiness here! I'm sure we all know the famous foot-in-mouth part in Star Wars IV: A New Hope, where Han Solo says of the Millennium Falcon: "It's fast enough for you old man. It's the ship that made the Kessell run in less than 12 parsecs." Well we, of course all know that a parsec is a unit of distance, and so George Lucas made a bit of an error here. Or did he? Whilst in a relativity lecture last month, we were introduced to the idea that time can be measured with units of distance, in fact this actually becomes necessary whilst calculating differences in the observations of time intervals by observers in differing inertial reference frames. To turn time into a unit of distance, one uses the equation Δτ = ctwhere c is the speed of light and t is the time interval. Well working backwards from this then, we can extrapolate that without lying a jot, Han Solo quite correctly stated, in Relativity Jargon, that he made the Kessell run in About 4.1 seconds. Not too shabby, Han old buddy, not too shabby at all. I'm now waiting patiently to be told how wrong this is!
  9. 1 point
    Just got back from the dark site, had Luna imaging in mind and thats all i got, these images shot at prime focus on auto using Tal and micro four thirds olympus, single shots, just wish i could get the hang of stacking a few shots to improve them
  10. 1 point
    Hi I was just playing around with one of the remote iTelescope (previous called gras) scopes and decided to go for a shot at the Trifid in narrowband This was 9 mins in Ha, 9 mins in SII and 24 mins in OIII on the Sidlng Spring T30 scope I processed this in Pixinsight using pixel math (red = Sii + 0.3*Ha, green = Ha, blue = Oiii + 0.4*Ha) after a bit of trial and error I realise I need a few more subs but there are a few questions 1 - any suggestions for next subs, it is already very bright in Ha after 9 mins so I guess more SII? 2 - any suggestions as to what pixel math combo's might be better 3 - in order to capture the blue reflection nebula, am I correct in thinking I need some subs through a blue filter? This is a rough play in PI, if anyone wants the individual Ha, SII, OIII channels for play I'm happy to post them
  11. 1 point
    I've just spent a couple of hours with the Bresser Messier AR127L on the moon. That in itself is amazing, as I've never before devoted more than 15 minutes at the end of a session on the subject. The view just seems to have more three dimesional 'pop' than my 300 Dob and I found myself with the 8.8mm jammed in the diagonal just roaming around the lunar surface. I'm going to have to get myself a good moon map to find out what all of this stuff is.... However, that's not the point of this post. Aside from a brief daliance with a WO Zenithstar ED80 II 'Apo' when I was kidding myself I had the time for imaging, I've never had a refractor for purely visual purposes. In the process of researching the AR127L I have ended up with, I read much about the control (or not) of the false colour an achromat delivers. However, finding actual images to illustrate what this false colour realistically looks like is hard, so even as I pointed it at the moon for the first time, there was still a certain amount of trepidation. That there would be some colour fringing was beyond doubt. As to whether I would find it too distracting was another issue. Long story short - I'm as happy as a canine with an even number of appendages. I then thought it would be interesting to try and take a picture that realistically represented what I was seeing, for the benefit of others who may follow down this well worn path and lack objective information on which to base the decision. I took a number of photos with an EOS 450D at 400 ISO, file size 'L', with differing exposure lengths. the one that best represented the visual experiance was 1/125 of a second. With a bit more effort, I could probably have improved upon the focus, but that was not the information I was chasing. Here it is as a 100% crop, saved at 80% Jpeg compression in GIMP, but otherwise completely unretouched: I'd be interested to see other peoples images taken and treated the same way. Standardising on the ISO and subject would be useful, with only the exposure length changed to compensate for different F ratios. Failing that, I hope this helps someone Googling as I have over the last couple of months. Russell
  12. 1 point
    hello to everyone. first off i would like to lend my appreciation to this site. i have been slopping around reading the forums over the past while, and i have found all comments and replies to be very informative, and those doing so to be friendly. so thank you. i have been interested in astronomy for many years, and my equipment has never extended more than books, my eyes, binoculars and an understanding girlfriend who would suffer me rattling on. my said good lady decided to add to her suffering (or a ploy to give her some peace on cloudless nights), and bought me a celestron nextstar 127 slt mak (500mm focal length f11.81) for my birthday. my first night out has hooked me completely. seeing Jupiter and her moons sitting astride was breathtaking, and iv'e been shaking my fists at the clouds and wind since. i'm now looking to upgrade my eye pieces. first on my list is a barlow x2. there-after i find myself scratching my head as i pour through websites wondering if the eye piece kits on offer would be the best route to go with, such as celestron's own kit with plossl pieces and filters. iv'e set my budget at around £150, though i will take a hammer to my wee piggy bank if it would suit to spend a little more. any advice would be grateful.
  13. 1 point
    I set up the telescope and binoculars for a spot of daytime observing of the Moon and am pleased because with the weather forecast I have at the moment... I'm all good to go for some observing from my own back garden!
  14. 1 point
    The ISS taken with a Canon 40D at the prime focus of a Celestron EdgeHD 925 Scope: International Space Station by ejwwest, on Flickr ISS travelling from right to left
  15. 1 point
    A 15 pane mosaic of the Southern part of the Moon and a single frame of the Alpine Valley - from last night:
  16. 1 point
    Hi. I use a pair of Burgess Optical binoviewers with my 200p. They are 2nd/3rd hand. Work well with a Barlow lens. Just upgraded the focuser to a low profile model ( available from FLO). This now enables focus without the Barlow. Cracking views of the Moon, Jupiter and Saturn since I bought them. Reccomend a purchase. Have to presume tho WO viewers will work for you in a similar way. John
  17. 1 point
    If I remember it was a thread by Psychobilly regarding focusing on a star that is at the intersection of two 1/3 lines on the sensor. I can't find the thread right now though..... Thanks, Anotn
  18. 1 point
    Thanks, with only £500 difference between the 9.25 Deluxe and 1100 deluxe I kind of want to get the largest aperture I can especially as this would have to be a keeper. I have had a few 8's and I think the 9.25 would be too similar. The 11 will realistically be the largest scope I own. Still, I've heard the 9.25's are very nice.
  19. 1 point
    I wanna see the stamp he puts on that when he posts it
  20. 1 point
    They would say that in the US wouldn't they? They don't live in Rip off Britain. Only you can decide whether or not the preposterous premium of the Edge series is justifiable (over and above the already very high price of the regular CPC series).
  21. 1 point
  22. 1 point
    The failure rate does make me nervous about any manned mission.
  23. 1 point
    All three colour images will be stored separately in the fits file. As Steve says, you have to output them from Fits Liberator individually and then combine them into a colour image in Photoshop. Andrew
  24. 1 point
    It's nice to know that taking the mickey out of Ebay is alive and well on SGL! Well Royal Mail has increased it's prices recently, but not that much. Well spotted.
  25. 1 point
    To be fair, his first line does say it's only there to fill the box ... but then again, having to pay someone £10M for going to Corby isn't that far out AndyG
  26. 1 point
    So, Skywatcher, Meade, celestron, orion optics, in fact all telescope makers have it wrong then. All we need is a bit of MDF and a tube of silicone? No ones noticed this before so all that talk of mirrors biscuiting and needing proper support is hot air and nonsense. We can simply stick it to a sheet of MDF with three blobs of silicone.
  27. 1 point
    Wow thanks for all the advice! BST's it is. clear skies. Rob
  28. 1 point
    Um, which one is supposed to be the better then ? Myself I would go for the 102, but you don't actually say which one you would. There is nothing worthwhile between the f numbers and at f/6.9 the 102 is easier on the design and glass properties. There is a lot more then just reading an f number and plumping for whatever one is lower.
  29. 1 point
    It is a shame that this eyepiece has had its reputation tarnished with these seizing issues. It really is a great eyepiece to have in your case. I certainly wouldn't make your decision based purely on this thread, I think people will more likely come online to share a grievance with a product but rarely to praise said product IMO. I had my first zoom for almost 2 years with no problems what so ever, based on the pleasure I've had using it I would still recommend one, certainly for beginners. Greg
  30. 1 point
    one more time but with numbers already in for most popular apetures and focal lengths. (note add you numbers in mm) CA index calculator.xlsx
  31. 1 point
    I will turn up for a chat and a cuppa on the Saturday, As I live all of 10 mins drive from the site I won't stay the night (comfy bed vs lumpy tent hmmmm, no contest). My scopes are firmly bolted into the dome so won't bring kit but it would be nice to meet some other members in the flesh. Robin
  32. 1 point
    Hi Scott, i know exactly what your question meant & i have often asked the same thing. Does half the Iso mean i need to do double the exposure, in theory yes if all things were equal but there are a lot of variables involved & i am no expert, i lost three 300 secs & two 600 secs subs because of planes & satelites Friday night. Also i have found that a 60 sec sub is about 22.5Mb & a 300 sec sub is 25.3 Mb so not that much larger (in case anyone was thinking they would be a lot bigger). I would stick with Iso 800, if LP is problematic use a filter, they do work, on a side note though, if vignetting using 1.25" is a problem keep the target dead central then crop it later. Here are 2 images one at Iso 800 @ 61 seconds the other is Iso 800 @ 300 secs, the 60 secs is fine but the finer detail will be missing, yes it's not as noisy but that can be taken care of, the 'pinky' colour can also be stretcvhed out as well. Iso 800 @ 61 secs Iso 800 @ 300 secs
  33. 1 point
    I will take some dslr shots with Tal100 and olympus pen tonight if its clear
  34. 1 point
    Hi , i've had a try with a number of different battery techs, lead acid, Nicad, dry cell, NiMh, lithium ion and lithium poly. They all have pros and cons. For price,capacity, Toughness, cold performance the lead acid is hard to beat. The only big down side is weight. The battery memory effect everyone talks about is a bit of an urban myth. Batteries lose the ability to hold charge after cycling many times and some techs have low discharge thresholds that need to be stayed above or they get wrecked. Also lithium needs charging in a different way in that the volts can't exceed a set level or fire/explosion occurs so the final charge does'nt delta peak it amp reduces. I have built nicads and nimh for years for radio control racing and even those, famous for memry effect can be reconditioned using the correct charging methods. If i was to guess at the next wave of batteries for scopes it would be lithium polymer but they can be dangerous, especially if shorted or got wet. I have had two fires and one big pop during my rc flying, they are nasty when they do go.I have a 5 amp pack that I have tried with thye scope but matching voltage is difficult as each cell is 3.7volts nominal (3 would give 11.1 volts or 4 would give 14.8) so not ideal for a 12v usage. To recap i use a 12volt booster pack (a mac one) mainly heavy but rock solid. tons of amps and with an attached charge level indicator and my eq6 will last all night, probably two.
  35. 1 point
    Just having a think about the sharpness drop off. Could it be the way I observe that introduces the error? It would be hard to articulate this so I drew something to explain (in case it isnt obvious im quite visual - i always feel the need to draw things..) In 1. This is standard obseving with eye square to exit pupil and head square to eye. looking at the central part of the field and observing edges only in periphial. in 2. tracking an object across the field without moving head, the eye moves away from the exit pupil leaving some light not entering the eye. in 3. head tilts around eye which remains central this allows you to look into the eyepiece at an angle but keeps the pupil central to the exit pupil light shaft. You need to move slightly closer so that you line of sight remains within the exit pupil light shaft. I find 2 works if the object isn't tracked far out from centre but introduce kidney beans and blackout on 82 degrees so I use method 3 for UWAs. I was using method 2 for the BGO as the field is tighter. Could this introduce out of focus, sharpness loss/blurring? Obviously when tracking an object in this way the on axis is not your focus so I couldn't say the quality. you can only see what you're looking at (obviously). I did also try method 3 at the field stop itself and it was definitely no where near as sharp as on axis / method 1. about half as good id say, thats a notable loss of performance.
  36. 1 point
    Never say never I guess going to check my scopes collimation today. Didn't do them last night when I put them out so they might have been slighty off the sweet spots. I wouldn't have thought this was coma at all given the magnification it would've been utilising only a small central part of the mirror not the edge where coma is usually introduced at low magnification. which uses the whole mirror. This is much more like a collimation error or simply the eyepiece just doesn't like the scope. It's be good to get an honest report from someone with the same exact scope and eyepiece. Our maybe even have someone confirm what I'm seeing on mine. I've plans to meet a board member in the near future so maybe can do that then EDIT: I did a mock up of a photo of Plato at about the same moon phase as last night versus the sketch i did. The red circle is a match. the blue circle I saw as one but is actually two. the green area is where I saw a white line crossing the crater, barely visible in the photo though and the yellow circle was where I suspected there was another but couldn't say for sure. turns out it was one so I think that counts. I now believe the real challenge here lies in visibly splitting the pair in the blue circle
  37. 1 point
    There is a good explanation in the help files for Deep Sky Stacker, available here http://deepskystacker.free.fr/english/technical.htm#Drizzle I've successfully drizzled guided images, but perhaps that means my guiding isn't all that good!
  38. 1 point
    Improvise, adapt and overcome is the name of the game sometimes when it comes to planned trips out bush. I had planned to take a walk into some pretty advanced bush this weekend but as things turned out, I wasn't able to get it sorted by Saturday morning when we were leaving. Instead, I rang the national park to ask about another alternative. Unfortunately, there were scheduled burn-offs in progress, making fire and smoke a hazard to avoid there. Plan three was to negotiate from the bottom of some cliffs into the creek below. We climbed the mountain, took the climbers track to the bottom of the cliffs on the other side and subsequently found ourselves blocked by very steep and dangerous terrain at every turn. There just seemed to be no safe way to go about it. Might have to come back to crack this one when I have more time to take it slow and safe. Plan four came as a relief to not only me, but my two companions as we decided to turn south and head to the very summit of the granite tops in our area. Not only did this mean less effort to actually get there, but it allowed us to truly relax and take in the serenity of the mountains. The sounds of a solitary Lyrebird echoed out of the tree-line below us. Apart from it's signature resonance giving away it's true identity, the animal expertly imitated a pink and grey galah, a Red Wattlebird, a Currawong and several others. Apart from this and a few other small birds, this weekend I was struck by the lack of wildlife. We saw a few lizards and skinks, some wrens and even some female bower-birds, but that was about it. I really was hoping for the wedge-tailed eagles I know to frequent the area but alas, no show. As God caressed our faces with His temperate breeze, the sun slowly made it's westward descent over the smouldering fires before retreating into thick clouds. That kind of spoiled any afternoon light for the landscape side of photography, but as night blanketed the sky, the top sheets of cloud peeled back to reveal the Milky Way in all it's glory. Time to break out the torches for a bit of light painting, complimented by Canberra's golden river of street lights blazing upward into the remaining cloud cover. One magnificent boulder on it's own looked great with the fires burning in the background and the Australian Aboriginal's dreamtime Emu stretched it's black neck and head up to look over skeleton trees desperately holding onto the rock in their last-ditch effort to stay upright even after life has left them.
  39. 1 point
    Similarly there has been work done on alpha, the fine structure constant looking long distances to signatures in quasars. E.g., http://prl.aps.org/abstract/PRL/v107/i19/e191101
  40. 1 point
    Good to see you here. I've just joined myself and am in a similar situation. I'm trying to find the best set of EPs to start collecting. I've so far got a 20mm plossl and a 25mm excel. I like the excel and will be going for a smaller one soon. Beware of the variation in prices and definately shop around, I've seen them from £89-£69 each. good luck Stu
  41. 1 point
    that was going to be my next question, i have the 25mm but with my new scope (150pl) the mag will increase slightly from 40x to 48x and seen as BST dont make anything after 25mm is it worth going for a 30/32 but this would be around 40x so would it be worth it??, so i guess you may have cleared that up for me already probs go for the 18mm and then might as well get the 12mm in for a penny and all that!
  42. 1 point
    Hi Rob I have the same telescope as you which I have had for about three months now. I pretty soon bought an eyepiece to replace the 10mm one. My choice was the 8mm BST Starguider as I was looking for something better to study the moon and Jupiter. Hopefully I will get good views of Saturn when the skies clear up enough down here. I am delighted with my choice as it is a great eyepiece that is sensibly priced. The Starguiders have great reviews on this forum. I am still using the standard 25mm eyepiece that came with the scope for DSOs, which I find actually isn't too bad an eyepiece. My next investment will be in replacing that one for something of better quality, and there is loads of good advice on here. Good luck with your choices. Cheers, Phil.
  43. 1 point
    One of the best small sites I've been to! Lovely place, top notch facilities! See you all again, I hope. Matt
  44. 1 point
    Not sure I'm too happy with this hypothesis - needs some thinking about. Preliminary idea in my head says that the debris from the Death Star would continue to orbit at the same altitude as the undestroyed space station. Will do some more thinking and report back You can tell if I were in the Star Wars Universe I'd be employed by the Empire's Health, Safety and Environmental Bureau!
  45. 1 point
    OMG! No it's me - I forgot to add it. Here it is :-
  46. 1 point
    Another possibility is to check the guide rate you have set in EQMOD - I think the default is 0.1x. Try increasing it to 0.5x
  47. 1 point
    Hoping to make SGL9 or maybe 10 depending on how quickly I can finally get round to learning to drive. In the memetime however, I found this and felt the need to share
  48. 1 point
    We've had a beautifully clear evening here, just north of Copenhagen, and I was quite surprised by how much higher Panstarrs is than when I glimpsed it on 15th, and also by how bright it still is. I think that if we get another evening as clear as this, the EQ6 and Tak are going to be coming along for the ride in the car... This was with a D700 and 85mm f/1.4 (at f/3.5, 4s and ISO 800):
  49. 1 point
    The FLT-98 is, from what I have heard, the jewel in the crown of the William Optics range. I really believe that you can't go wrong with it (and would also suggest that resale values will always be pretty good). As a decent imaging scope then it's a good bet as is the TSAPO90, the quality of which I can personally vouch for... Mount - well the SkyWatchers are always well reviewed on here. There is a lot to be said for tried and tested... My first decent mount was a Celestron CG-5. It was rather an uninformed purchase, but I still use it today for imaging with my refractors and it performs well. It's also light and easy to move and for a portable set-up I'd suggest a smallish refractor and a lightish mount offers the best combination. As to guiding - I'd really recommend off-axis guding. No problems with flexure, no more expensive than a guide scope, and lighter into the bargain...
  50. 1 point
    As you say Nigel the GOTO is not a miracle worker though to be fair you do have a choice of alignment stars so don't have to use the first one it suggests. All you need to know are 2 bright stars visible from your location preferably fairly low in the sky. Using the GOTO is rather like a satnav.....its adviceable not to throw away your map book.
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