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Showing content with the highest reputation on 07/11/14 in all areas

  1. 6 points
    I was at the Kerry Dark Sky Reserve last weekend giving a workshop on DSLR photography. We managed to get to a 2000 year old circular Stone Fort to protect us from the windy weather, and to go deep into the dark areas of the reserve. Highest SQM measured during the certification was 21.87, that's dark. Here is just a quick and dirty image 25s of the milky way pointing the camera north, along with a 2nd 25s image for the wall without the light painting . I love the step features on the walls. You can walk all along the top, and complete a full circuit on the 4m thick walls. The lighting was just from a mobile phone light. This was taken with a Canon 7D and a Tokina 11-16mm lens. 3200 iso, and f/2.8 Tom.
  2. 5 points
    NGC 6888, the Crescent nebula, very near to Sadr in Cygnus is thought to have started formation about 250,000 years ago. The central star is very massive, and has a solar wind so strong it has blown off roughly the same mass as the sun every 10,000 years. This wind has collided with gas that had been shed by the star in a series of shells in the past, and the wind has heated it and caused to glow. At a distance of about 4700 light years, the light that those of us who’ve imaged or viewed this have just received left at a time that saw the start of the bronze age, the beginning of writing and the spread of agriculture. World population was between 7 and 14 million. Not long ago in the big scheme of things In this image I’ve set out to get as much depth in the OIII as I could, rather than concentrating on the Ha as the dominant filter. The OIII in this target is often treated as a kind of second cousin, but it’s really interesting, and very different in structure from the Ha. Imaged in June and July 2014 from Weymouth, Dorset. Telescope. 12 inch Ritchey Chretien @ F5.3 Camera. Atik 460 EXM, Baader filters Ha. 16 x 30 minutes OIII. 16 X 45 minutes RGB. 11 x 5 minutes for each filter All subs binned 2x2 Ha-red, OIII-green and blue RGB stars added as individual 'lighten' layers to each mono sub master Captured, calibrated and stacked in Maxim and processed in PS CS6.
  3. 5 points
    Hi All, I am in the middle of doing my NEQ6 power connection mod and wanted to blank the original. I came up with this, if anyone is on the lookout for an idea. It is the end of a Bic biro, with two wraps of gaffa tape on the stem for a really snug fit, it just pops out with a Stanley blade when needed.
  4. 5 points
    That was a big mistake.....now they are free to roam at will across the whole forum, scaring innocent little refractor owners ;-) Sent from my iPhone using Tapatalk
  5. 5 points
    Apos Rule!! Who needs aperture when you can squint down a 2.5" scope and imagine you are seeing all kinds of things ;-) Sent from my iPhone using Tapatalk
  6. 4 points
    It was only about a year ago that I saw the Veil Nebula for the first time. Myself and a couple of others were out late one night with our scopes when I noticed the Argo Navis indicating the Veil was up, we had always supposed that we were too far South here in Perth Western Australia to get any sort of view of it. Anyway I hit the goto button on the Servocat and the scope slewed straight to it very low of course. I could view the Veil through the 28" standing on the ground, no ladder, we were all laughing so surprised that such an iconic object had escaped our view until that moment. It was was a very memorable occasion.
  7. 4 points
    I've been comparing the 10mm and 18mm Baader Classic Orthos to a wide range of similar focal length eyepieces over many months now. The competition included Baader GO, Fujiyama orthos, Astro Hutech orthos, Pentax XW's, TV Delos, TV Ethos, TV Plossls and quite a few more. In my early comparisons I suspected that the 18mm Classic Ortho was showing just a little more contrast and brightness in a range of deep sky objects including galaxies and that has been confirmed a number of times now against all the eyepieces I've compared them too. One of the comparisons I did involved the starfield in Orion where the Horsehead Nebula is located. It's my ambition to visually detect this object this Winter so I've been getting to know the starfield as well as I can in preparation for the "right night". Comparing the view with both just the eyepiece and with the Lumicon H-Befa filter fitted (which I'll use to hopefully tease the Horsehead out) the Baader Classic 18mm and 10mm orthos consistently show the faintest visible field stars more easily than other eyepieces and actually showed a couple of stars that had not been hitherto visible. These comparisons were made with my 12" dobsonian on a number of nights where the conditions varied from moderate to good. I found the same thing earlier this year when observing the long lasting supernova in the galaxy M82. The Baader Classic 10 and 18 showed both the faintest stars and the dark rifts and brighter knots in the galaxy just that bit better than other eyepieces did. Not that the others were particuarly poor in any way, the Baader CO's were just a tad better. The Baader CO's are not perfect eyepieces of course and their field of view is on the narrow side for manual tracking and I feel that the Baader GO's, Fujiyama and Astro Hutech orthos are better for viewing the Moon and planets because they control light scatter around bright objects just a little better than the Baader CO's do. If someone can lend me a couple of Zeiss ZAO's I'll happily compare them with the Baader CO's and report back Alvin Huey and friends in the USA have done something similar and found the Baader CO 10 somewhere in between the Delos 10mm and the Zeiss ZAO on faint galaxies with some very large aperture scopes. Here is another short comparison from last year, this time between the Baader CO 10mm and the superb Pentax XW 10mm: http://jaysastronomyobservingblog.blogspot.co.uk/2013/08/david-vs-goliath-in-eyepieces10mm.html
  8. 3 points
    Hi I managed to shoot some SII and OIII data last night to finish this off although for part of the evening I was shooting through bonfire smoke and then high mist at the end of the night. Although conditions could have been much better I'm still pleased with the final result. This was taken with the Televue NP127/FLI astrograph on my Paramount ME with exposures times of 24x10 minutes Ha, 22x10 minutes OIII and 30x10 minutes SII. There is plenty of Ha and OIII but the SII is very weak. Hope you like it The full size image can be seen at the following link http://m4.i.pbase.com/o9/29/869929/1/158125374.hYQ7hd5B.Sh2132HSTfinal.jpg Best wishes Gordon
  9. 3 points
    My very first imaging session on Uranus! Not much else to say really just a blue ball. Seeing was dreadful and with a full moon next door conditions were not great. I took several mono red avis at around 8fps up to 10000 frames mainly captured with a 50% histogram but they have come out too bright even when using 3x drizzle but for some reason the only colour shot which was only 1000 frames from 2000 has come out best (or least worse!). Auto Dob 250 & QHY5L-II C with 3x tv :
  10. 3 points
    I been off for a while and I do apologise for not checking back but I was really busy (work-work-work) and envy...I had a SkyWatcher 130 EQ - bought that coz everybody said its the best starting scope, WELL - I did grow out that little scope extremely quickly. But it did help to improve my knowledge, and get a experience. But now I have a new one and oh dear it does makes the 130 to look like a dwarf. Since I bought the DADDY it never stopped raining so I decided to construct a nice light shroud and dew shield. Later probably a setting circle and digital angle gauge and lastly flocking the whole OTA. I can not wait to get it out and just cruise the night sky.
  11. 3 points
    Hello Thank you friends astronomers. Two others images with barlow 2 : Good day.Luc
  12. 3 points
    Hi just like to thanks for the warm welcome really enjoyed the night and I will be back. Thanks Damian for the talk really interesting and informative. Thanks again Mark
  13. 3 points
    Thanks for that Soupy and to all our members and guests that attended and didn't fall asleep, hope it wasn't too hard to follow. Good to see everyone and nice to see new faces too. Lots to come in the following months keep up the good work guys Damian
  14. 3 points
    Hi Olly, Thanks for looking as suggested I have given it a dose of SCNR, strange I can't see the green cast on my pc... have to watch out for that one! also there is a lot of Ha in the egdes and SCNR messes with that a bit. I have also noticed that it looks worse on the 1Mb version that's on here. I have also pulled the core in a bit, again I didn't want to overdo this as you see so many that have been overcooked on the compression, but I think I have improved on it. see what you think??? I hope you're well Olly all the best Colin
  15. 2 points
    Lucy-Richardson deconvolution is a bit of a hot item at the moment, and I have found it very useful in sharpening solar images, producing clearly superior results to the wavelet sharpening I had been doing before. After some playing with the algorithm, and implementing it in C, I thought it might be a good idea to make an attempt at a simple explanation of Lucy-Richardson deconvolution (also at the request of bigmakstutov). As all deconvolution methods, it tries to undo the blurring caused by optics and seeing. The effect of blurring is to replace every point source (star) in the image by a little blob called the point-spread function (PSF). While most obvious on stars, the effect is also present in extended sources. Here, the value of each pixel that it should have had without blur, is replaced by a weighted sum its original value and that of the neighbouring pixels. This process of replacing pixels by weighted sums of the neighbourhood is called convolution. The effect of convolution with a small blob is to lose fine detail and sharpness. In theory, we can perform a so-called inverse filter, which undoes the convolution, but this only works in the absence of noise. The key problem is that the noise in the image is not convolved with the PSF. This means that fine detail in the noise is not lost in the image. Inverse filtering boosts fine details indiscriminately, causing the fine detail in the noise to explode. The LR deconvolution method is different in that it does not directly invert the process of convolution, but tries to estimate an image which when blurred by the PSF is as close as possible to the original input (or observed image). The idea behind this is simply that the observed image is a mix of the desired, unblurred image, convolved with the PSF, plus some Poisson noise (photon and dark current noise). Therefore, the aim is to find an image that, when blurred with the same PSF, gives a result consistent with the observed image. In the following we assume that some estimate of the PSF is known (a Gaussian function often works well). The process starts with some first estimate (which can be the observed image, or even a flat, 50% grey image). At each iteration it computes a correction factor for each pixel, and multiplies each pixel of the current estimate with this correction factor. The correction factor approaches 1.00 as the process approaches the desired, deconvolved image, because multiplying by 1.00 does not change anything. The set of correction factors for each pixel forms an image in its own right, so computing the correction factors can be done by processing images. The first step is to convolve a copy of the current estimate with the PSF (we blur the current estimate). We then divide the observed image pixel by pixel by this blurred estimate. This yields a new image, which is then blurred by the PSF mirrored in the origin (i.e. you flip it horizontally and vertically). As most PSFs used in this context are symmetric this need often not be done. There are however cases in which you need to do it. After this blurring, you now have the desired correction factor. All that remains is to multiply the correction factor image with the current estimate, and go to the next iteration. I did wonder about the behaviour of the correction factor in the case that the blurred current estimate contained zero values. This would lead to division-by-zero errors. A short analysis shows that this can be avoided by setting all correction-factor pixels to zero at those locations (or to any arbitrary factor). The reason for this is that these zero values in the blurred estimate occur only where the current estimate is zero itself. Whatever we use to multiply those pixels with, the result remains zero. As you iterate the effect is to creep closer and closer to the final image. If the process converges (which is not guaranteed) adding more iterations does not sharpen the results further. What can happen is that more iterations become unstable due to noise, or a poor estimate of the PSF. In this case the pixel values can start to oscillate around the correct value. To prevent such oscillations some versions of the method introduce a strength parameter, which I think decreases the step size of the iterations. The idea is that more, smaller steps will not overshoot the desired solution. If the PSF estimate is wrong, this will not help much. Thus, when optimizing the parameters, focus on the PSF is more important than the number of iterations, unlike e.g. iterated unsharp masking. I do often enhance the image with a bit of unsharp masking after LR deconvolution One key problem in deconvolution is knowledge of the PSF. In most cases it is supposed to be known, and often a Gaussian function with width tuned by the so-called standard deviation sigma can be used. There are methods called blind deconvolution which try to estimate the PSF as well. If you do have knowledge of the PSF, it is best not to use these. Here are some results on prominences. The first image uses wavelets, the second LR deconvolution: I will post a GUI-based program which allows batch processing later.
  16. 2 points
    Hi Every one, I found some data I had not processed from Mid July of this year I think this was first light for a new camera lens I had purchased, It was quite nice finding the data, and bit of a challenge to do anything with it as there was only 8 exposures at 5 minutes long. Fairly pleased with the result considering, a bit noisy but to be expected Taken with a modified Canon 1100d at 150mm fl iso400 at f2.8 all on top of a eq6 pro, Darks used, processed in DSS, PI and PE. Paul
  17. 2 points
    ....more AP firsts for me from last week M41 NGC2287 Canis Major 100s GSO 6" F4, Fuji DSLR @ ISO1000 M46 NGC2434 Puppis 100s GSO 6" F4, Fuji DSLR @ ISO1000- the more eagle eyed may also spot planetary nebula NGC2438. M47 NGC2422 Puppis 100s GSO 6" F4, Fuji DSLR @ ISO1000 M67 NGC2682 Cancer 100s GSO 6" F4, Fuji DSLR @ ISO1000. The FOV also shows two galaxies NGC2661 & 2651 & two open clusters 2664 & 2678
  18. 2 points
    My mum does a lot of sewing and as she is visiting this weekend, she made me this. An astro cushion cover.
  19. 2 points
    Not a good day for imaging, started with the Quark / B'Fly but seeing was rubbish plus gale force winds and the USB socket on the quark started playing up had to strap it to the side with a velcro strip, think I'll need to get a cable with a right angle plug to stop it flapping about. Impossible to focus the Quark so tried the LS60 which proved a lot easier, except then Firecapture kept dropping the camera, eventually managed a couple of videos then gave up as the wind was horrendous. And looking on Helioviewer I just missed a nice flare by 30 min's So this is the result of a couple of hours faffing about, just shoved through A'Stakkert and P'Shop without altering any settings, bit gaudy Just goes to show you need a Quark and an LS60 as I told Mrs T but she's still not convinced Dave
  20. 2 points
    Kirkster501 Interesting you should mention the focuser slip. This is what Ian King had to say when I questioned him today: "I think there will always be a small about of play in any rack and pinnion focuser. The focuser is fully adjustable though so you can experiment with tensioning it to your requirements. A word of advice though, Takahashi put some kind of screw lock substance on the tension bolts. My instructions from Takahashi Europe are that if customers wish to adjust the tension on the focuser they need to use some acetone or nail polish remover to remove the screw lock first. In fact I am going to France in a few weeks to spend a day with Takahashi Europe to get first hand instruction on how best to adjust these focusers." So, maybe Ian can help once he's been instructed on how to do the adjustment. Regards John
  21. 2 points
    There are only two types of astronomers,those who dob and those who wish they could :0)
  22. 2 points
    I've 100% respect for the way you want to undertake astronomy Steve, and everybody else too I think we each devise our own way to approach it taking into account a whole load of things. If it works and puts a smile on your face thats what matters
  23. 2 points
    I have not seen the design but I've made one of my own. However it is still early days so I can't comment on dewing. Mine has separate main mirrors which makes finding suitable items a lot easier. They don't need to be coplanar as long as they can be adjusted to be parallel. There is a third mirror so I can aim it with a laser pointer. It is not finished but here is a picture. There have been some developments since it was taken.
  24. 2 points
    This is the last night's moon. GSO 12" F/5 Canon Rebel XS 29 frames ISO100 1/1600s each Full res: http://www.astrobin.com/full/134408/B/ Cheers
  25. 2 points
    I like my old Takumar M42 lenses, they are 40-45 years old. The Andromeda above was taken with a 135mm f3.5 Super-Takumar that cost me £18 off eBay. This is probably my best effort with it, 30 minutes of data (2 minute subs) on the Heart & Soul Nebulae, with the Double Cluster on the right.
  26. 2 points
    TBH I'm not sure I do agree with John on this. I don't see one or two nights a month as it being any more than just a hobby. I don't see a couple of nights a month as abandoning my family either. Its simply a different way of pursuing it. If one wishes to only observe at home thats fine obviously, but those of us that choose to go to dark skies are certainly not losing sight of it being just a hobby. For example I've not bought an eyepiece in over two years how many others can say that? Are those that spend money frequently taking from their children's inheritance ..........of coarse not. its just a hobby
  27. 2 points
    Is there a second rule? Or can't you talk about it? Dobsonian rule #1: Ensure that it's as big as possible - aperture fever really pays dividends
  28. 2 points
  29. 2 points
    the first rule about the dob mob is never talk about the dob mob....... I agree, or at least am unaware of a specific section in the forum.
  30. 2 points
    Thanks John I was quite happy with my eyepiece line up until reading this!! BCO 10mm now on the Christmas list. Paul
  31. 2 points
    Hi Guys, I took the data last week for my version of M42, was a bit of a mission to process as I had a few different exp lengths. I'm pretty happy with the outcome? it's made up from: LRGB 15s,60s,120s,600s , Ha 60s, 600s total lights 17.3hrs taken on my Tak106FSQ reduced, Avalon mount, Atik 460Ex all processed in PI please let me know what you think. many thanks Colin
  32. 2 points
    Pretty much agree that south-ish is what's needed, also make sure that you're not facing the houses in the same road when looking south. Use google maps when looking for a house, and take a compass with you. Yes you may get some strange looks but tell them you're an astronomer, I did. Also have a good look around for horrors such as floodlit sports grounds and insecurity lights.
  33. 2 points
    Unless binoculars are on a mount there pretty pants and for a child to hold them still is going to be a no no. A small dob is the way forward.a 6" dob will show you the great red spot and gas bands on Jupiter.the brighter globular clusters will be resolvable and galaxy's will be easy to see. Yoyr child can explore the craters on the moon in far more detail than a pair of 15x70 celestrons which I have and think are pants. Seeing shadows inside creators will surely be a wow moment for both of you.
  34. 2 points
    binos are a reasonable cost alternative but i always find keeping them still very hard so i`m not really a fan of them myself.
  35. 2 points
    Yes - it's important to consider the extras when deciding which scope to buy. For a refractor you'll probably need a field flattener/corrector matched to the scope. Possibly a dew heater as well. For a reflector you'll need the collimation tools and a coma corrector. It may be a bigger scope (for the same price) so might need a correspondingly larger mount.
  36. 2 points
    SPX350 F4.5, ST10XME with Astrodon filters. Not imaged here for a while as weather has been windy the last 6 months in SE Queensland but I managed to grab a quick Orion Nebula. Created a different image in Hubble palette and also managed a close up with my Mintron CCD at 3 meters to get the faint stars in between the Trapezium. M42 gets to 70 degrees alt from Australia and the ST10XME is fantastic for narrowband. Ha-12x5min OIII-20x3min SII-12x5min Ha/OIII/SII-16x5secs each for trapezium stars. Thanks, John.
  37. 2 points
    Splendid, Splendid, Splendid. Happiness is a new scope! Don't forget the first light report. That sounds like an epic day's shopping. Looking at your signature, where did you get the last item on the list?
  38. 2 points
    You only live once cobber http://www.nicholoptical.co.uk/1310%2020%20inch%20F4.2.htm
  39. 2 points
    Really enjoyed talk from Damian. Having done engineering in a past life I appreciate the skill and serious finesse in the manufacture of this beast of a scope. Sent from my iPhone using Tapatalk
  40. 2 points
    Oh I've seen what dark skies can do Calvin. But it's just a hobby .....
  41. 2 points
    Hi Paul I'm probably not the right person to give advice here as I am a DSO junky and for me dark sky trips ARE what its all about. For me buying larger and larger apertures to use under so so skies is like chasing phantoms. The main advantages of larger apertures are image scale and resolution, but the object must have detail in order for us to resolve it. A featureless blob will otherwise become just a larger featureless blob when a bigger scope is employed. Contrast is where the detail is, to get contrast we must have dark skies. Don't get me wrong any detail that can be seen will be improved by aperture but just don't expect objects to "Pop". Only dark skies can do this. I'm not trying to talk you out of a larger scope, just to be realistic in your expectations. Dark skies are what DSO observing is about, not giant apertures Good luck with your decision
  42. 2 points
    Another one from the same 'marathon' session last week. M50 Monoceros 300s, 150mm F2.9 scope, Fuji DSLR @ ISO1000 And another...... M48 in Hydra 300s, 150mm F2.9 scope, Fuji DSLR @ ISO1000
  43. 2 points
    Hi Um, I can see a whole lot of frustration and wasted time ahead... Why not do yourself a favour and just start with a dslr instead? Louise
  44. 2 points
    It was a lovely clear moonlight night yesterday and I went out with the intention of re-doing my NGC 2210 sketch but it was far too low and barely visible so I had a look for something else to have a go at. NGC 6510 was quite high and showing quite well so this is my effort. It's more of an impression than pinpoint accuracy but I'm quite pleased with it. Afterwards I thought I'd do an SGL search to see if anyone had posted anything about NGC 6510 and came across this thread. I was surprised to say the least when I realised I started it. You know you're getting old when .........-
  45. 2 points
    After buying my first scope ever in october and after first light 2 days later, I had to wait for the sky to clear up and then... The moon came out ! I rushed to install everything in my kitchen (see my other post) and after "wowing" my wife and 5 yrs old daughter with an amazing view of the moon through the ocular, I installed my moded toucam webcam at prime focus on my C6. The moon appeared in all it's glory on the screen of my laptop and I captured 1 thousand frames of it. I then used PIPP and Registax, fiddled with wavelets and contrast. A blurry and awful image came out of it. I spammed my family and friends, like a toddler showing it's first mess of a drawing, I got polite "nice", "keep at it" as replies but still ... I am happy because that's what it's all about. The joy of astronomy. In the grand tradition of this forum: I present to you my 1st attempt at The Moon ! I was able to identify the second one as Archimedes and Montes Apenninus, but with the flips and mirror, not sure about the 1st.
  46. 1 point
    First is a terminator mosaic with panes of 640x420 and the second is a "full frame" image of the northern part of the Lunar disc. All using my 120mm APO and ASI 120MM, red filter and a frame rate of 100+ fps. This camera is certainly fast!!
  47. 1 point
    Thanks Guys I'll aim for a 16" SW or may consider a Lightbridge depending on price / level of modding required. What Luke and Kerry discribe is just the sort of observing that I am after.!! Not that I'm ruling out the odd dark sky excursion, but it will be very much the exception to be savoured as much for the company as the view. At least I know what I am aiming for now. Paul
  48. 1 point
    I would recommend to anyone doing this adjustment manually that the screws that you make this adjustment to are not the best quality. I like to make sure mine are locked off nice and tight and when I made the adjustment I twisted the head off the screw. Bearing in mind that I'm talking nice and tight, not Hulk tight, if I were doing the same again I would 1. take it easy with the stock parts and 2. think about replacing the screw with a decent one before doing it. Just my experience.
  49. 1 point
    ... And almost as a postscript to your post and another (Moon Convert), tonight there is the most gorgeous halo around the moon above me. It's all very well knowing that it's caused by ice crystals and that it's nothing more(!?) than a rainbow - the fact is, it is wonderful to look at. Colour on the inside of the ring; apparently darker sky within the ring, and the feeling of something 'big' which is above and beyond us. No wonder poets have been inspired by lovely Luna.
  50. 1 point
    Alright, but I do worry that making the Kielder area more attractive to casual tourists can only lead to one thing - the degradation of the excellent skies that are available there now. More accommodation will have to be provided, be it hotels, hostels, campsites or whatever, and that will inevitably lead to more light pollution. Not everyone who goes will be that interested in astronomy, so more amusements will have to be created for them. Make no mistake, if it comes to a decision by the relevant authorities - should we preserve our dark skies or should we make more money? Money will ALWAYS be the winner. More traffic means more streetlights - even in a protected dark-sky site, 'elf & safety will pounce on it. OK, I'm painting a dismal picture based simply on the admirable ambitions of the guys at Kielder Observatory. But these are real concerns.
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