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Showing content with the highest reputation on 14/10/17 in all areas

  1. 6 points
    At long last the sky stayed clear enough for me to obtain 3 hours of data in 10 min subs of the elephant trunk nebula. The only option was to use my HA filter as this image was taken at full moon.This is the longest period of continuous time I have been able to image without guiding playing up or running into any other problems e.g. the dog getting caught up in the cables to my mount and cameras. I'm still very much wet behind the ears when it comes to this imaging lark but I feel I am slowly progressing. I had a lot of problems controlling the stars in processing this image and any advise or comments would be much appreciated. I'm hoping to get an O111 filter so there is the chance of bicolour imaging as long as the sky behaves and there are no other pet related incidents.
  2. 4 points
    Hi everyone. This was a 'Is it doable at 1200mm?' session. It's quite small and the 18x4min snaps make it noisy. It maybe worth adding a few more frames. Or am I flogging a dead newt? Thanks for looking and clear skies.
  3. 3 points
    Finally got the rig together, Solarmax 60mm double stack with BF15, dodgy mount needing something a bit more accurate than push and shove, Altair Astro gp-cam, a Think Tank cover and my sons laptop.
  4. 2 points
    1st images of the sun in years, nice prom
  5. 2 points
    Yep and then there were, still are motor cycle jackets Belstaff's, combine with a Harris tweed or Norwegian wool sweater and your core is good for anything sweeping in from the North. Thin layers will trap warm air in-between, just a different approach, both will work and I would welcome some artic air this winter.
  6. 2 points
    A daylight Moon - After a regular session photographing the Sun I thought I'd have a go at the Moon too! The moon was high in the sky so it gave a good opportunity. ED120 APO, Canon 1100D, 1/640sec, 100 single frames taken. PIPP was then used to crop the frames followed by AS2! to stack 60 from the 100 taken. Then Lucy-Richardson deconvolution in Astra Image to sharpen. Quite a few gentle iterations of curves in Photoshop to try and get some contrast back, followed by a tiny bit of sharpening. The original colour image has been changed to mono.
  7. 2 points
    I agree with Swamp Thing on trailers. They are great destroyers, although many US observers use large, stables ones for Dob transport. There are misconceptions regarding the Serrurier Truss (as seen in Swamp Thing's avatar.) Some people think they must be less rigid than tubes but in fact the design is very clever, it's key feature being that it maintains the secondary in the right attitude even if it flexes slightly. However, it isn't a 'pop up' design so does require assembly on arrival. For something large and portable I'd certainly have a look at David Lukehurst's website before deciding. Olly
  8. 2 points
    Just came across this...smart idea me thinks!
  9. 1 point
    The Moon as it dances through the solar system doing a endless waltz with its partner Earth. kit starwave 102 classic, 1200d, HEQ5. 72 frames staxed with reggie. I'm looking forward to seeing everybodys images. good luck and clear skys. charl. best viewed in full res.
  10. 1 point
    Taking advantage of the work of my colleague Jr Martini who is doing a detailed study on the Linné crater, I would like to draw attention to another little known formation that can be seen in this photo. This formation is in fact composed of two Vallis and a rhyme of a very peculiar and practically unique format on the Moon. I searched for information on these Vallis and actually did not find anything specific other than names and location. If anyone is aware of any work that deals with them be sure to inform me! July, 02-2017 C14 Edge + ASI 224 + PM 2X http://www.astrobin.com/full/316009/0/?nc=user
  11. 1 point
    Well last night, my partner's Aurora alarm app went off whilst we were having dinner - so pudding had to wait! We loaded the tripod and camera bag into the family truckster and headed off to Corton Beach under cloudy but clearing skies. Sadly, the street lights dont go out until midnight so Corton Beach, relatively close to our house, provides a dark site with a northerly view back over the cliffs largely missing the 'orange glow' that is Great Yarmouth. Whilst we were on the Beach the clouds began to clear and both of us thought we could see a green glow over the cliffs and just below the tail of the Great Bear. Anyway I took a number of photographs the best of which was taken whilst the app was telling us that photography would show the aurora from most of England. I have attached the image - 20 sec exposure - ISO1600 - F3.5 - tripod mounted Canon 600D DSLR - 18-55mm at 18 lens which has had the following image processing : Application of autocolour at about 20% Colour saturation enhancement using LAB color and adjustment of channels by increasing contrast. Colour blurring using a gaussian blur. Saturation of red and yellow colours reduced to reduce the orange red glow of some 'low pressure' sodium street lighting that I could not avoid when taking a photograph looking north. General lowering of saturation across all colours and some repetitive luminosity layers to finish I think it shows some auroral activity. Looks very much like the low level auroral display that I photographed in Tromso several years ago. But as my partner says when I reach for the 'imaging software' - "Cheating again" - So who knows for sure ? A bit of a bonus was the very dark sky view east out across the North Sea. Quite beautiful. We watched the Pleiades rise out of the sea and the Milky Way was absolutely marvellous. The dark lanes of dust could be traced with your finger and the Andromeda Galaxy was an easy spot with the naked eye. I took a sequence of images more or less centred on the Double Cluster in Perseus - 6x20 secs RAW-ISO3200 f=18 and F3.5- stacked in DSS - FITSwork etc. I do like widefield astro photography and very much enjoy reading articles and viewing widefield images created by Professor Ian Morison - I have some way to go! It was very nice to see a couple of meteors - one was quite bright - and to capture the less than bright one shooting by and just under Messier 31 - an exposition in 'near and far'.
  12. 1 point
    Sunny skies today but rather windy. Seems it was prom day on the sun today, below are the ones I managed to capture. And a couple of H Alphas to round off the set.
  13. 1 point
    I also got a new cap for my vx14 because the one I've got has a big hole on it for stopped down observing, but the highlight was finding a second hand dual speed focuser for my maksutov!
  14. 1 point
    That's exactly what it is. Useful when you've a DSLR's weight pressing down on it.
  15. 1 point
    Ah, that would rather be the focal ratio myth ;-) As said in many other threads, and as debatable as it may be, focal ratio wins. The focal length is as much relevant as it's linked to the focal ratio. And IMHO Ikonnikov is right : depending on focal ratio (at fixed aperture) the object image is more or less stretched in the focal plane, so that ends in more or less photons per pixel. Yes, the overall photon quantity is the same, but you only capture a part of them corresponding to your FoV. Edit: BTW, I didn't grasp your setup, but the reducer should be irrelevant as it's only a way how to achieve shorter focal length and lower ratio; Again what seems to count is the effective focal ratio (just as with lenses after all).
  16. 1 point
    Looks brighter in the reduced image exactly as I would have expected. Same number of photons spread over less sensor area / pixels due to the increased field of view. You increase signal to noise at the expense of reduced resolution.
  17. 1 point
    Packing Light = Putting the red torch in! :-D
  18. 1 point
    David Hinds mirrors are good - most were 1/8th wave PV, some were even better
  19. 1 point
  20. 1 point
    The tolerances in diameter don't matter, any M4 metal screw will enter any M4 hole tapped for metal screws, but metal M4's are 4mmx0.7mm when plastic screws are 4mmx0.8mm because the more fragile material needs to have thicker threads. A plastic screw will turn a little inside a metal thread and then bind. When I tried to replace the broken nylon 4mm screws in my GSO finder, I found I had to enlarge and tap the holes in the 6mm format, which is identical for metal and nylon screws alike, fortunately. To make eyepiece holder screws less aggressive, I put a nut and a counternut just under the screw tip, so only a fraction of a millimeter is visible. After that I rub the tip against fine sandpaper to make it smooth and square to the screw's axis. A final polish on a rough kitchen sponge makes it easier on eyepiece barrels.
  21. 1 point
    £309 https://www.firstlightoptics.com/skywatcher-mounts/synscan-pro-goto-version-3-upgrade-kit-for-eq5.html
  22. 1 point
    I believe that to be irrelevant! The program takes calculations from your scope positions to align the MOUNT, you not aligning your guidescope alone to Polaris.
  23. 1 point
    http://www.sharpcap.co.uk/sharpcap/polar-alignment
  24. 1 point
    @newbie alert Is 5 degrees not like 10x diameter of the full moon?
  25. 1 point
    Thank you all. Lots to consider. My 12" mirrors give (what I think are) good views. They are heavy Hinds late 1980s Pyrex and cooling down only takes 30 mins. I like GOTO, so perhaps a dob with that hardware should be more an equal consideration though tracking down objects can be part of the fun. Though I love sat nags when driving rather than map orienteering.
  26. 1 point
    The "compare-the-curves" exercise is strictly only valid for a single frame (= 3 exposures) white light source, without any weight factors in creating the rgb image. DSO imaging is an entirely different beast. The Astrodon I-series red filter looks much more orange than the E-filter, but all that light is pressed into one red channel anyway. In principle you let orange light count as red. I think that someone imaging from a light polluted site should more carefully examine the filters. But in that case equalising fluxes is of less concern. I can imagine that if comparing the various filters, you'd say that one set gives "cleaner" or "crisper" or "more saturated" results, but that may depend more on other characteristics than bandwidth. E.g. reflections or glass quality. Adding Ha to the mix, offsets the balance, as you noted.
  27. 1 point
    That sums up my journey beautifully Alfian.
  28. 1 point
    Nice build... an Obsy is a lovely thing to have & makes such a difference. The neq6 & my back was the deciding factor for doing mine. It won't be long before you'll be wanting to motorise the roof & automate from the house.. trust me ?
  29. 1 point
    When I bought the zwo asi 174mm, I also got the standard lrgb filters. Since then I've done the math and calculated the best exposure ratios between r, g, and b. In retrospect, I should have also done that for the asi1600 optimised filters, to compare. Anyway, I found the ratios to be 145:100:107, for r:g:b. I.e. red needs 45% longer single frame exposures than green to get a proper colour balance from a white light source. The problem is that if I use this and shoot different exposures, I will also need to do different darks. That's the whole reason for getting optimised filters in the first place. The Astrodon filter sets e-series and i-series are designed for red and green sensitive chips, respectively. You'd have to do the math to match the filters to any camera. On casual inspection, the (new?) Baader set seems to be similar to the ZWO optimised, with two exceptions: 1. The green and blue filters overlap at Oiii, while H-b signal ends up in the blue channel only. (Good thing) 2. The red and green have a larger overlap at the sodium line. (Bad thing) Based on filter curves alone, the Baader set may actually be poorer than ZWO in handling light pollution, and the Astrodon should outperform both (it better, at that price). But beware, this comparison is solely based on published filter curves, NOT on actual experience, mechanical stability, reflection properties, or other optical characteristics.
  30. 1 point
    Good luck, I look forward to hearing how you get on. If I can, I sometimes like to take a short nap and then freshen up prior to setting off. As others have stated, take layers, food and a flask and when you arrive, try to block off all internal car lights. It is a good idea to begin by returning to targets that you have some familiarity with. A good chance for seeing structure perhaps such as M33 and the Andromeda galaxy group will be much brighter, expansive, wait until you have become fully dark adapted and have observed a few other objects before hand. Hope you enjoy being out there underneath the Milky Way, if it goes well, it can become additive.
  31. 1 point
    tonight's moon was observered at 05.40am gmt in hessle England due to the phase of the current moon not much was on show except 3 craters at bottom of moon and 1 half way up here is a picture to show current phase of moon I am just amateur at astrophotgraphy at moment so don't expect Hubble space telescope pics lol pictur was taken with celestron 20x80 binoculars and Samsung j5 mobile phone enjoy
  32. 1 point
    Also my first visit to one of these things, and i second everything seemed bigger, the Tec 140 looked incredibly fat. Like you say wouldn't go often but was interesting to see the stuff in the flesh
  33. 1 point
    I have 3 quad USB cards in the obbo PC as well as the motherboard connectors. So my worry is not that a single connection will draw too much but that the sum of the connections will overwhelm the psu.
  34. 1 point
    Unfortunately ISO1600 is the highest a 400d can do (unless there is Russian firmware hack to increase this)
  35. 1 point
    Happy birthday for when it come around... I have the 14" GOTO model.. and it did deliver some amazing views so go ahead and spoil yourself... just be aware that they are big scopes. Consider the GOTO... it really helps out when you just want to observe and not hunt... if you want to hunt for objects manually, than you can unlatch the fears and use it as a standard Dobsonian.
  36. 1 point
    As my partner's aurora alarm went off, so did we to the dark delights of Corton beach car park. Looking north we thought we could see something other than the Orange glow of Great Yarmouth 10 miles to our North. So I took a few 20 second images at F3.5 and ISO1600. I then realised how dark the site was and decided to take a few images of the Milky Way running through Cassiopeia and Perseus. Andromeda was naked eye bright as was the Double Cluster. The Seven Sisters had just appeared out of the North Sea horizon. Quite a lot of people lurking about in the dark on and around Corton Car park and I'm pretty sure few of them were Stargazers. Hey - ho it takes all sorts. George now in bed after an hour or two of image processing. Will post the results tomorrow in blog format. Nighty night stargazers wherever you are.
  37. 1 point
    This isn't just a nice image. It's a great image! 60 seconds exposures. Detail in the Orion nebula, a clear horsehead and flame. Control of the bright stars, and showing faint dust. This image has it all. The two things I would add to the work flow are to try to reduce the smaller stars, to calm the image down a bit. And use noise reduction on chrominance to get rid of the colour mottle in the faint dust. But those are minor issues. Thanks for sharing.
  38. 1 point
    An increase from 12" to 14" is unlikely to give you the wow improvement that an upgrade should bring. Paul
  39. 1 point
    Yes it is helpful to have understanding parents. My parents share the same astronomy passion as me which is a huge plus.
  40. 1 point
    You see the word "Sale" and buy 2 of something that you already have or don't need ... human nature i'm afraid
  41. 1 point
  42. 1 point
    Hello The 16 " skywatcher dob are a big beast. But with more aperture you get more light gathering ability and therefore the ability to see more especially DSO, atmospheric ,weather and very important light pollution problems permitting. If you are considering going for a big dob then I do think a scope like this needs to be in some form of outside obs. As in my opinion it is not practical to keep taking it outside and setting it up. You will quickly get fed up with this routine and the scope will not get used. Also you will need to let the mirror cool and the collimation is likely to need far more adjustments.The best scope to get is the one which will be used. I was considering the 16" skywatcher but decided on a more managable 14" Orion optics solid tube. Still great light gathering ability. Lighter to lift , less collimation issues. Fits in a medium sized car. Most of the benefits of a bigger scope but with far less drawbacks. If you are considering maybe a 14" I think I am correct that Helen on SGL has one for sale a 14" OO( I understand she has now got a obsession) . So may be worth a look if interested. I hope the above helps.
  43. 1 point
    A photo that does not need to comment, just made to admire! http://www.astrobin.com/full/312948/B/?nc=user
  44. 1 point
    This is what I managed with a WO ZS61 & a full frame nikon D810 on the star adventure, not a great image i know but it will give you some idea of what you can expect regards field flatness you would be better off leaving your sony in full frame mode and crop later if required.
  45. 1 point
    Hi all, Just wanted to share first (promising) test results from new algorithm that I've implemented. Algorithm deals with normalizing / equalizing subs prior to stacking. Because target position changes over the course of shooting session we end up with frames that are a bit different one to another. Each frame has some (usually different) amount of LP, depending on target position in relation to LP sources, and also signal recorded depends on altitude of target at a given time due to atmospheric extinction. It can also vary with transparency, fog or passing clouds. For advanced stacking methods to work well frames need to be adjusted - signal multiplied with appropriate coefficient and LP subtracted. Simple average method does not need this, but algorithms like sigma clip, or auto adaptive weighted average do. In general case we can't determine proper values, but we can do frame normalization based on a reference frame. My new algorithm deals with this and as a bonus it has capability to minimize LP gradient, depending on reference frame selected. So if reference frame with low LP gradient is selected, whole stack will match that level of LP gradient. In ideal case if we have single frame without LP - all other frames would be adjusted accordingly. For test case I've chosen some data I shot about a year ago (actually on December 30th 2016). Target was M78 and conditions less then ideal - a lot of fog/haze (and smoke from neighborhood chimneys) and the usual amount of LP but really showing because of all the problems with transparency. Data is shot with OSC camera, and I've selected green channel for the test. Data is of low quality, hence so much noise in examples - it is not due to algorithm I've chosen 3 different reference frames to do normalization upon, one that I've judged as having the least LP gradient, one with LP gradient somewhere "in the middle" of the bunch, and one with rather high LP gradient showing. After normalization I used basic mean / average stacking, and did basic exposure stretch in gimp. Here are results: Stack of frames normalized based on frame with least LP gradient: Medium LP gradient: High LP gradient: And in the end just for reference, composition of these 3 stacks, because difference in level of LP is a bit difficult to judge unless blinking images (then it is really obvious), from left to right - the least, medium, the most lp gradient reference frame: For the end, I would like to stress that this is not "gradient removal tool" - it does not operate on already stacked images, it is part of preparation of subs for stacking. It will not fully remove LP gradient, it will reduce it to levels found in reference frame - so reference frame needs to be chosen accordingly. Any comments and questions are welcome, Thanks for looking.
  46. 1 point
    Yes, but PixInsight do not free software. Astro Pixel Processor is another commercial software for astronomical image processing. StarTools is post-processing image editor.
  47. 1 point
    Hello, I know about these free programs: Image processing 1. Siril is meant to be Iris for Linux (sirI-L). It is an astronomical image processing tool, able to convert, pre-process images, help aligning them automatically or manually, stack them and enhance final images. Free. 2. AstroImageJ is ImageJ with astronomy plugins and macros installed. It includes tools based on the Göttingen ImageJ astronomical resources with additions we find useful. Because it was necessary to modify the original ImageJ code to enable some of these features, this package should be installed in its entirety. Free. 3. MicroObservatory Image is a simple to use, yet powerful astronomical image processing program that works with FITS and GIF files. Free. 4. Lxnstack is a program designed to align and stack astronomical images (both planetary and deep-sky) by Maurizio D'Addona. Written in python and qt for the Linux platform it is released under the Open Source GPLv3 licence. Free. 5. Regim is a software tool for processing astronomical images. Free. 6. THELI GUI is a powerful and easy-to-use package for astronomical image reduction, offering e.g. Free. 7. nip2 aims to be about halfway between Excel and Photoshop. You don't directly edit images — instead, like a spreadsheet, you build relationships between objects. You enter formula (or select menu items) to describe how to make a new object from some of the objects you already have. nip2 keeps track of these relationships: if you make a change anywhere, nip2 automatically recalculates anything affected by the change. 8. GIMP v.2.9.7 is a cross-platform image editor available for GNU/Linux, OS X, Windows and more operating systems. It is free software, you can change its source code and distribute your changes. 9. ImPPG performs Lucy-Richardson deconvolution, unsharp masking, brightness normalization and tone curve adjustment. It can also apply previously specified processing settings to multiple images. All operations are performed using 32-bit floating-point arithmetic. 10. Stackistry implements the lucky imaging principle of astronomical imaging: creating a high-quality still image out of a series of many (possibly thousands) low quality ones (blurred, deformed, noisy). The resulting image stack typically requires post-processing, including sharpening (e.g. via deconvolution). Such post-processing is not performed by Stackistry. 11. C-Munipack is the software package, which offers the complete solution for reduction of images carried out by CCD camera, intended on a observation of variable stars. Each step of reduction process can be run from the command line or via simple and intuitive graphical user interface. 12. AstroAviBrowser is a small tool for astronomy imaging processing. With AstroAviBrowser, you may open a video file, select the good frames and save the new sequence in a new avi file. It also debayer your raw sequences. Free. 13. cvastroalign (video align tool for astrophotography) is a program that loads a video sequence, aligns and stacks the selected frames obtaining an image as result of this process. 14. Munipack is a free open source tool for processing of astronomical images. 15. Asterism is a Linux (astronomical) image preprocessing tool for consumer digital camera (CDC) RAW images and many other file extensions.
  48. 1 point
    Observing Information DSO - M35 Date - 08/03/17 Time - 21:00 Lunar Phase - Waxing Gibbous 85% Seeing - Poor Equipment - Celestron Nexstar 6SE Eyepieces - ES 24mm 68 degree It's been a good 6 months since I've sketched a DSO and I have to say it brought tears of joy to my eyes. My object of choice of course was an open cluster M35 before I got to this magnificently rich cluster I observed the moon for a time an M45 fiddled about with my DSLR camera which I must admit is starting to annoy me just something to eat up my visual observing time. Anyway I turned my attention to M35 not to sure what to expect and wow was I surprised, the sheer amount of stars in the whole FOV was simply overwhelming. I was using my ES 24mm 68 degree EP and I have to say it filled the EP gloriously I must have spent a good hour sketching and even then I don't feel I did it justice. Anyway it's good to be back and I'm sure my next sketch won't be as long as my last. Clear Sky's ?? Richard
  49. 1 point
    I am so glad that i have limited mobility or else my aperture fever would be so much worse. I am over the Moon with my Celestron 8SE, but to be honest if i invested time and money and had an Obsy built in my garden i would have a 14-16" scope of some kind housed there all year round. Size really does not matter in astronomy, once you enjoy how and what you do with what you have.
  50. 0 points
    Focal length is irrelevant. When you use a reducer, you change the focal length by definition, so it is not in consideration. Only aperture and F ratio. According to the myth, the druid itself should be the same brightness in the unreduced and the reduced image. We are only considering the FOV of the unreduced image
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