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Showing content with the highest reputation on 13/08/19 in all areas

  1. 9 points
    Before starting an imaging run I now do some test images with different filters, exposures, and binning to see which combinations work best. When I examined the OIII 1800s bin 2x2 test image I was surprised to see an asymmetric outer shell with intricate structures, and so factored this into my image capture plan. This is the result. There is also a very faint diffuse OIII shell that is even further out from the core. I found processing this to be a real challenge, with 7 filters, and exposures varying from 30 sec bin 1x1 to 1800s bin 2x2. Integrating images with such extreme dynamic range was also a challenge. I was concerned by some lighter parts of the sky background, but after checking with other images available online it became clear that this was integrated flux nebula. This is a total of 57 hours of integration. Captured on my dual rig in Spain. Scopes: APM TMB LZOS 152 Cameras: QSI6120wsg8 Mount: 10Micron GM2000 HPS
  2. 8 points
    Attached are Jupiter and Europa, Saturn, Copernicus Crater. All taken with ASI120MC, SW150/750 and 2x Barlow.
  3. 4 points
    Some Politician will Blame Brexit before too long
  4. 4 points
    Cue the slightly out of focus and ever so shaky video - not much different from my astro photography work Jim
  5. 3 points
    Hi, this is my first proper attempt at an LRGB image. I chose the North America Nebula and framed the shot to capture the Cygnus Wall. What do you guys think? Do the colours look good? I think my focus was off slightly for the red channel as the stars look a little bloated? 120mins integration time 1x1 binning. WO Z73 + Altair 183m Pro Tec + Baader LRGB filters Thoughts, comments welcome as I really want to learn and improve! Thanks
  6. 3 points
    You are of course right. I'm sorry for the misleading information on my part. I totally misread the situatuion here tho... . When I read the first post over agian. I thought from reading the description in the post (very poorly read I might add), that the board was powered by 12V itself. I totally missed out the fact that there is also another power supply here. This combined with the fact that I did not have the datasheet for the IC lead me to believe that the device is something that it's not. Sorry for that. I don't want my name associated with things like "that cocky new guy who just writes something something so it looks good" , as I am not that guy. I didn't read/check properly, and was wrong . . I will be more careful next time hehe.
  7. 3 points
    Disclaimer: I don't do DSLR AP, but understand what happens, so will try to explain. Let's first talk about what ISO is. ISO is in principle multiplicative constant. As such it does not impact your image in any way with regards to SNR - which is important thing in AP. If you have some sort of signal that is let's say 100 units, and associated noise is 10 units (photons / electrons, whatever), and you apply high iso - you will be multiplying with some number like 10, so resulting signal will be 1000 and noise will be 100. Signal to noise ratio remains the same. Image remains the same once you scale it to display range 0-255. So in principle nothing major happens with high / low ISO with regards to captured data. On the other hand, there are things that happen when you change your ISO settings - read noise depends on ISO, and usually low ISO has higher read noise, and higher ISO has lower read noise. This will have some importance later in discussion. Another thing that ISO does is change your effective full well capacity. Let's say you have 14 bit DSLR. This means that digital values produced by your camera can have values in range 0-16383 (integer values). Actual signal that pixels detect can and usually is higher than this. In order to map hole range that pixel can receive to limited range of 14 bits - you need to divide it with something. Let's say your actual full well capacity is 60000 electrons. You need to multiply that with 0.25 to get values in range of 0-15000. Such values fit 0-16383. But when you select higher ISO, you will be using only portion of your true full well capacity. Sometimes with very high ISO you might end up having less than 14bits effective full well capacity. For example if certain ISO has multiplicative constant of 2, then actual electron count from 0-8191 gets mapped to output of 0-16383, and you end up having smaller effective full well capacity. Now back to your question about blow out. Only thing that makes a difference between stacking a few longer subs vs many shorter subs (of the same total exposure) is read noise. Or to be precise, how "important" read noise is. There are a few sources of noise (shot, thermal, LP, read noise) and difference between few longer vs many shorter comes down to how "big" read noise is compared to other noise sources. Maybe best way to illustrate this is by using triangles, as noise adds as linearly independent vectors: If read noise is close in magnitude to other noise sources like LP noise this happens: Total noise is larger than both read noise and LP noise. But if read noise is far less in magnitude to some other noise source - in this case LP noise, than this happens: So difference that read noise makes gets minimal and there is almost no difference between few longer subs vs many short subs. With lower ISO you will effectively have larger full well capacity, and LP signal levels will not occupy significant portion of the range, so single sub will not look blown out, but lower ISO will have larger read noise - which means you need to again swamp your read noise with LP noise in order not to make difference. What all of this means is: yes you can change ISO but there won't be any significant improvement in stacking result. If you have high background LP signal at 90 seconds - just use those exposures - going longer simply won't produce better results.
  8. 2 points
    I decided to combined all the images from my meteor camera into a few composites images. I had a total of 89 confirmed Perseids over three nights, which I was very happy with. This plot shows the position of the meteors relative to my location. Thanks for looking.
  9. 2 points
    You can do it in AutoStakkert3. (before you do any stacking) When you load up your AVI file, two boxes appear. The 'image' one has a sliding bar thingy on the top which allows you to step through the frames. Get to your transit ones and export each of the frame individually. Then a bit of Photoshop adding....... I did the process yesterday and got this....
  10. 2 points
    Many of them are actually quite small and easy to over look. Once you identify them you can push the mag up and often they become more distinct and easy to compare with the Skysafari image as the fainter stars become visible.
  11. 2 points
    Later it just got enjoyably better with a slight Milky Way at the zenith. A check showed sqm of 19.47, ace for the edge of town. Spent most of the time on Cassiopeia, enjoying the open clusters here . Went for a few lesser known King and Cr clusters. Of these King 12, King 21 , Cr 463 and Cr 36 stood out from the field of stars. Pleased to attach details below, makes a change from the norm ! Into Lacerta and the spectacular sparkling NGC 7209 and NGC 7243. Then a horizontal view , laying down to look at the views overhead and that theatre of Wonder from Cassiopeia to the front of Pegasus. Over to Perseus and the lovely triple Σ 162 (SAO 37536) . A great view of Σ 314 (SAO 23674) showing lovely twins 1.5" apart. Always a wonder to get an insignificant star then observe at high magnification. A brilliant challenge is ψ Cassiopeiae (SAO 11751), tease out the companion to give a triple group. Iota Cass. gave a great view. Pleased to attach a few bits of Cassiopeia. A wonderful calm, dry and warm few hours, under , Clear skies ! Nick.
  12. 2 points
    https://github.com/deepskystacker/DSS/releases/tag/4.2.2-Beta2 This release is all about performance, though other areas have been enhanced as well. The main changes since 4.2.1 are: 1. Changes to star registration code to detect larger stars than before. Star radius of up to 50 pixels is now valid (it was 20 pixels). This was needed to accomodate higher resolution sensors. 2. Allow larger star sizes to the specified in the Star Mask creation dialogue. Star diameter of up to 100 pixels is now allowed. This was needed to accomodate higher resolution sensors. 3. OpenMP speedup of Star Mask image reading code. 4. Huge speedup of final image display by using much larger rectangles and OpenMP speedup of the bitmap extraction code. 5. Speed up star registration by updating progress indicator once every 25 iterations instead of each iteration. 6. Computing Final Picture using Kappa-Sigma Clip processing is now about 50 times faster! 7. Computing Final Picture using Auto Adaptive Weighted Average is now about 43 times faster! 8. Auto-Adaptive Weighted Average now re-written completely. It should no longer produce whited out images or other strange results. Thanks to Michael A. Covington and Simon C. Smith for their immense help in locating references and getting this working. 9. Update LibRaw to 0.19.3. 10. Reverted Entropy calculation code in CEntropyInfo::InitSquareEntropies() to NOT compute in parallel - some called code wasn't thread safe. 11. Entropy Weighted Average complete stack of 50 lights is now about 20 times faster on my laptop, down from 4hrs 22min to 12min 55 sec. 12. Bug fix - changing "Set the black point to 0" or "Use Camera White Balance" after an image was loaded didn't change the rendering. 13. When loading raw files, check that the camera is listed in the LibRaw supported camera list. Issue a warning if not. 14. User request to change the file open dialog to default to *all* supported image types including raw files. 15. Three times performance improvement in star registration. Have fun David
  13. 1 point
    Galaxies, Planets, Nebulae are pretty easy, I kind of know I'm observing one if I find one, but even with the star atlas in hand and knowing more or less the scope is pointing in the right direction, I'm not always sure I've found an Open Cluster . Sure, there are pretty easy ones to identify like the Double but for those more dispersed OCs, those in Cygnus or Cassiopeia for example, that all seem wrapped up with all the other stars when do you get that 'that's it' moment? To be honest, a lot of the time I'm just guessing so do you have any tricks or tips? Thank you for you time and I hope this is in the right section
  14. 1 point
    Excellent image! I've tried this through both 7 and 3 nm filters. I captured nothing at all through the 7nm, but the 3nm is very promising. I came to the conclusion that OIII is susceptible to light pollution and any moonlight (compared to Ha), and I would never have captured it with the 7nm filter.
  15. 1 point
    Thanks PauI, I looked for a bit myself and didnt see any. Mostly these were early in the morning. But actually got quite a few on the 8th too.
  16. 1 point
    All my printers have just one nozzle(fast interchangeable btw) never regretted it, never needed dual nozzle systems. I always design/draw my own projects and draw/print in such a way I don't need to use support at all. Never used that 'Support' function as a matter of fact. And as Julian said, dual colour printing is just a gimmick indeed.
  17. 1 point
    Very good seeing giving good detsils on Jup - GRS just about to disappear though
  18. 1 point
  19. 1 point
    That is a damn fine effort. It's a beastly beast I used 4 hours worth of 30 minute subs at f4 and still it doesn't leap off the screen ! ( 5nm ) Dave.
  20. 1 point
    A number of deliveries have arrived and have already sold, the factory are currently preparing another order for us. Generally speaking ETA for the next delivery (includes CEM40 mounts) is end-Aug / early-Sep but if you email us the model/version that most interests you we will do our best to be more specific. HTH, Steve
  21. 1 point
    Hope it works out for you..........
  22. 1 point
    Good luck Nigella! Look forward to seeing the pics if the cloud stays away.
  23. 1 point
    Just a heads up after some hands-on practice: The 27" screen makes imaging far easier. I could have used a 24" but was glad for the extra acreage of the 27" at my normal viewing distance. The bigger screen can be split down into separate areas with different input signals if you like. Huge image scale makes focusing an absolute doddle. Either manually, at arm's length, or motor focuser. You would not believe how tiny a change in focuser drawtube position alters the critical sharpness. I was never aware of this on the 15.6" screen! In retrospect: Most of the focusing was complete guesswork. You can examine the seeing conditions directly on the live image on the monitor before and during capture. This raises an interest point about visual observation and choosing your moments of clarity. Here you can see those moments directly on the screen. Or not, if there aren't any. A bigger screen is highly recommended if you are still struggling with a small laptop screen for your imaging. The 2560 x 1440 resolution allows content enlargement to suit your personal taste. FireCapture was legible from the first attempt compared with my frustrating trials with 4k on the smaller 15.6" laptop screen. I have attached a couple of digital snaps I took of the screen yesterday to show the sheer scale of things. BTW: The sun was far more evenly lit on the screen but the digital camera couldn't cope. The seeing for Jupiter was the worst ever but it was huge! Thanks to those who responded.
  24. 1 point
    How about a solar system paperweight/lamp like this one - https://www.amazon.co.uk/Erwei-International-System-Crystal-Engraved/dp/B0787PP19H/ref=asc_df_B0787PP19H/?tag=googshopuk-21&linkCode=df0&hvadid=310734995700&hvpos=1o2&hvnetw=g&hvrand=12036510559397166866&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9045038&hvtargid=pla-564068933008&psc=1 There are lots of options if you ask Google
  25. 1 point
    Enjoyed reading your account of both events. Very nice!
  26. 1 point
    It cleared up really nicely here around 2am so I just set the camera up in the back garden. Saw a few beauties, but not too many. Going to see if I captured any on camera now
  27. 1 point
    I have had other older relatives with similar experiences, this was before TV so was not something they had seen elsewhere and imagined. My Gran was also very insistent that you have your doors open during a thunderstorm just in case..... Alan
  28. 1 point
    Thanks. Yes, had an Altair Astro ED 66mm ‘frac a while back which gave me cracking pin sharp views, but sold it on. If this one gives similar views it definitely won’t be getting sold on. Just testing the focuser on it by keeping it at 90 degrees with a diagonal and one of my heaviest EP’s in. Not moved a fraction on the 2 speed gear, which holds much better than a Crayford focuser I think, unless you spend crazy money on a top end focuser.
  29. 1 point
  30. 1 point
    Good to hear from you again Kev.
  31. 1 point
    great images well done
  32. 1 point
    A few clear hours gave me the opportunity to get my NEQ6s polar aligned last night, and once the first was done I left it collecting unguided subs of M27 whilst I started on the second. Unfortunately I couldn't get my Altair camera working on the second so I had to stop the first and pinch the ASI174MM off it. But never mind! This is the first DSO image I've captured for many years. It needs more and longer subs, and the stars are a little eggy, but I don't care :) 19 x 60s unguided, ED80 and ASI174MM. James
  33. 1 point
    Welcome back from me too Kev. Good to have you back. Enjoy your retirement!
  34. 1 point
    Mr Barnes, I believe you have already recieved a warning for this type of behaviour!
  35. 1 point
    I'm not sure about that one Rob. My understanding is that same sized exit pupil in any scope should give the same image brightness, the thing that changes is the image scale depending on the aperture. What I'm wondering is how you get the same exit pupil in a smaller aperture, longer focal length scope (which sounds like it should be a longer focal ratio). Can you give examples of the scope/ eyepiece combinations you are thinking of?
  36. 1 point
    Very nice "first go" at the planets. They are much better placed for you than us at the moment, so it is good to see some decent images to relieve the "withdrawal symptoms".
  37. 1 point
    Is this any good? Not sure if the motors are compatible with the SP or not so please check carefully.
  38. 1 point
    I got to try 2 examples when I reviewed the scope for this forum quite a while ago. The 1st arrived with a broken lens element within the tube. The 2nd was undamaged although the fit and finish was perhaps rather rough for what was then a £1,400 scope. The optical design had potential I thought, considering no ED glass was used, but I would not like to try and collimate one where the optics had shifted !
  39. 1 point
    You know, she's quite perceptive, your granddaughter :D Just wait until she gets chatting with the neighbours and tells them that grandad spent last night in the wendy house... James
  40. 1 point
    Very nicely captured, some fine detail visible there especially for a 90mm aperture scope. Good to see a Moon in the field of view as well.
  41. 1 point
    Ok.... I could n't resist...... I apportion the difference in quality on the the fact that the HST is closer to the gas cloud...
  42. 1 point
    Who you gonna to call after the Zombie outbreak.
  43. 1 point
    Great Stuff Stu! What a fantastic scope by the sound of it! I've certainly split it with my 127 mak (true aperture 119mm) - smaller than this the secondary will merge with the diff ring of the primary I imagine, but maybe still visible in nights of exceptional seeing. This is a stacked image of Zeta Her with my 127 Mak, together with a simulation using Aberrator for 119mm aperture:- Chris
  44. 1 point
    Wow this was a tough one for the judges - a very, very close run race with three images sharing 3rd place! Thanks to everyone who entered - it was a pleasure to look through these. Winners are: Orion belt, Flame, Horsey and the Great Orion nebula - Ha mosaic by moise212 IC 1396A (Elephant's trunk) by Epicycle Sh2-171 - Cannistra Bicolour by Uranium235 Cresent Nebula (NGC6888) by alan4908 The Wizard Nebula NGC 7380 by MartinB
  45. 1 point
    Thanks! I'm sure you'll get clear skies soon - I'd swap the UK weather for Texas any day!
  46. 1 point
    I've used their 10" dob for a few years and have been very pleased.
  47. 1 point
    I do agree with this Ronin. UHC filters vary in whether they include the Ha line or not so you have to look into the data carefully to understand what you are getting. I believe targets like M101 have plenty of Ha regions to study with the correct filter, not something I've done myself but I know of others who have. I have the Lumicon OIII and UHC filters, alongside a DGM NPB. The Lumicons have so for seen much more use, and I think they are fabulous. My own filters have very high % stats for their passing of the target frequencies, I think I just got lucky with them both. Mine are mainly used in a 4" scope as it's often all I can take with me to a dark site. That is a valid point to make too. People often think these filters are ways around LP and that you don't need them so much at darks sites. In my experience, they come into their own when at a dark site and with good dark adaptation they are very useable in a small scope. As Gerry says, using a large exit pupil in the smaller scopes really helps, and often the targets are widefield ones anyway, such as the Veil. In good conditions you can see the whole veil complex in a small, widefield scope using and OIII or UHC filter. Lovely stuff. My belief is that the Astronomiks have a slightly wider band pass than the Lumicons, so MAY be better in a smaller scope, but otherwise, QC and trading problems aside, I would get the Lumicon.
  48. 1 point
    Further to my commitment to bringing you reviews of eyepieces for the more conservative budget, today I review this: http://www.ebay.co.uk/itm/30mm-Ultra-Wide-Angle-80-degree-2-telescope-eyepiece-/380367730023?pt=UK_Telescope_Eyepieces&hash=item588faef567 A 2” 80 degree Eyepiece for less than £85? Hmm, let’s see what the catch is... I used the same review method and targets as my previous review of the 70 deg 2” eyepiece from the same retailer, this can be found here: http://stargazerslounge.com/topic/162318-stock-50-degree-25mm-ma-vs-2%e2%80%9d-70-degree-24mm-vs-60-degree-25mm-bst/ Read that? Good, let’s get on (If you can’t be bothered to read the whole thing I’ll paste the summary here): Summary 25mm BST – Very bright and contrasty image. Does suffer from comma’s and seagulling at the edge, but certainly not a major distraction. A 60 degree 25mm for £41 will always raise a few eyebrows, but does it perform? Oh yes. Highly recommended. 24mm 2” Now, you may think after reading my critique above I’m going to slate this one. Nope. We really must remember I’m reviewing a sub £40 70 degree 2” EP here and on that score I liked it and thinks it’s a bargain. Yes, the image was quite dark compared to the BST (I really don’t think we can blame that on the 24mm vs 25mm), yes the image starts off nice and sharp and rather quickly deteriorates as you get closer to the edge but you must also consider it’s plus points as in it’s cheap as chips and I’m comparing it against a BST which is arguably the best eyepiece you can buy for under £50. It’s a huge step up from the supplied MA and well worth the asking price of £39 for the “spacewalk” feeling alone. My personal choice here would be the BST, but if, for whatever reason, you must have a 2” SWA EP I can wholeheartedly recommend this one and challenge anyone to better it for the price. So, Dumbbell nebula first then. I’ll compare it to the 25mm BST, as that “won” the last review. This new monster was very pleasing. The nebula whilst obviously small, was clearly visible without a nebula filter, and, to my eyes, easily a match for the BST in that regard, so no complaints on contrast and brightness here; when I could finally get my eye comfortable. And therein is my first issue with this eyepiece, initially I found it quite difficult to find the “hot spot” and kept getting black outs all over. I must stress though, once you’ve found the optimum position, which seems to be with your eye literally just touching the eyeguard, not pressing against it. It does become much easier and more comfortable but it did kind of ruin my first impression. I couldn’t help but to “space walk” around at this point, and wow, what a feeling! The extra 20 degrees over the BST certainly shows it prominence! I even put the 70 degree eyepiece from the other review back in, and believe me, even 10 degrees difference appears massive. And awe-inspiring... I also took this opportunity to look at the colours of Alberio and the colours on the 80 degree eyepiece were just as vibrant, if not more so, than the BST. Very impressed. Anyway, scores for this part were 9 a piece for the BST and the 80 degree, but as I state on my other review, this is not what you’d use this kind of eyepiece for, really. So, after I’d finished pretending I was Luke Skywalker I thought it best to do something useful, so onto the Double Cluster we go, and for the ultimate test, edge sharpness! Again, what’s the point of having a massive aFOV if only a small portion of it is usable? I line up the double cluster and remind myself how it looks in the BST. Very nice, but does get a little soft towards the edge, as per my other review. So I pop in this new eyepiece, and the stars are easily as sharp as the BST in the centre so all good there, but I kind of expected that. I look towards the edges and notice they’re still quite sharp, I was quite surprised if the truth be told; this is an 80 degree eyepiece that is quite sharp across the field on an F6 for under £85? It certainly seems so. Notice, however, I said “quite sharp” as I’m being as objective as I can here. The equivalent Nagler, which I’m sure is totally sharp across the whole FOV is well over 6 times more ££ at £555 here: http://www.telescopehouse.com/acatalog/TeleVue_Nagler_31mm_Eyepiece_2__.html . There’s a group of stars on the bottom cluster as you’re looking that I call “the paw” as I think they look like, well, a paw. They’re fairly close together but can be easily split in the centre and to my surprise you could still make out each individual star right at the edge! Yes it gets a little soft at the edges, but no more than the BST, which is excellent in itself, and it starts to get coma about the same place as the BST (around the last 5 – 10% of the FOV). It also seems it suffers a little from field curvature as a tiny bit of refocusing seems to bring these outer into better focus. Let’s just think about that last paragraph for a second. BST quality views across an aFOV 20 degrees more (90 - 95% definitely usable)for an extra £40? Yes, that’s what I said BST 9 / 10 – a 60 degree eyepiece for under £50 doesn’t come any better, in my opinion. 80 degree 10 / 10; I’m still in awe now! Summary: Is it a Nagler beater? Of course not! Is it worth it? Hell yes! Would I buy one? Already have Did you spot the catch? Nope, me neither...
  49. 1 point
    Interesting review - thanks for posting it The 30mm 84 degree Widescan III that I used to have (the Moonfish etc are clones of it) was great at F/10 but suffered a lot in the outer 25% of the field of view at F/6. The Moonfish and their kin do give you ultra wide angle viewing though, for an awful lot less than the premium eyepieces of that type.
  50. 0 points
    Been pretty bad here too Charl as well sadly.
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