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Showing content with the highest reputation on 05/01/20 in all areas

  1. 12 points
    Rosette Nebula: Total 16 hours HaSHO with FLI ML16200 on Tak FSQ 130ED.
  2. 8 points
    The last time I was able to get outside and image was in September 2019. A combination of illness and bad weather managed to scupper any chance of getting the telescope out. In the meantime, I threw myself into learning Sequence Generator Pro and automating my gear so that I can control all aspects (other than dragging it out into the garden from the garage) from the comfort of indoors. The main purpose for last night was to test run SGP, acquire the step sizes for my motor focuser and then to test run a short image session to ensure the image sequencing, plate solving and guiding all came together. The bad news is the clouds managed to spoil any serious imaging and the Moon was at 62% illumination. The good news was my H-alpha filter was in the filter wheel and Messier 1 was ideally placed. The attached image is made up of 30 minutes of integration time (my shortest so far!); Lights 6 x 5 mins Flats 25 Dark Flats 25 Darks 25 Equipment William Optics Z103ED ZWO ASI1600mm Cooled Pro Baader 7nm H-alpha filter SkyWatcher NEQ6R-Pro Sequence Generato Pro Exposure Gain 139, Offset 21 I will certainly be revisiting Messier 1 in the near future. John
  3. 8 points
    I captured OIII data the other night and was able to get a bi-color image. This is my first color image of 2020 and it looks like it's going to be a good year for astronomy. This is a pretty quick process, I'm considering adding RGB for the stars but there are other great targets that I could be imaging... Probably won't be adding SII though, since my SHO images seem to turn out worse than my HOO ones. Ha: 55x430s OIII: 45x430s Thanks for looking, as always comments appreciated.
  4. 7 points
    I took a photo of Betelgeuse in February 2019 just because it's a pretty star - Thought I'd take another to see if it really has dimmed as much as everyone says and the difference is very noticeable - (prime focus of a 7" refractor with a focal reducer bringing it to f 5.6. )
  5. 7 points
    Following on from my post a few days ago of the crescent moon, I had a chance to go for a quarter moon on the 3rd January with the new ZWO ASI290MC on my SW120ED. A little sharper and less over processed this time, showing more real detail. I did have some odd colour banding going on that I have not figured out yet, so I have set it to greyscale which looks OK. There's so much to learn. Again kudos to Photoshop Elements for really simple stitching - it seems to adjust exposures to match as well. There was cloud scudding across the moon during the videos that does not seem to have upset anything.
  6. 6 points
    FSQ 106 / RD 645 / QHY 128C IC348 by Yves, on Flickr
  7. 6 points
    First imaging session in 4 weeks! A lovely 1st Quarter Moon. The whole shot using the new Canon 6D full frame camera and the detailed images using the Altair 290M camera. 3000 frames each shot and using the best quality above 60%, roughly 300-400 frames. Both on the LX850 12". I have had the GP290M for about 6 months and it has replaced my Altair 178C for Lunar. The Canon 6D (mod'd) has been added to my collection. I was very surprised how much Moon I could fit in the FOV compared with the 450D
  8. 6 points
    A few weeks ago, I moved the 18" Obsession from it's shed to another room inside of the large barn, for easier access to the paved yard. The view is more restricted now, but I can wheel out the scope (wheelbarrow handles already attached) and start observing within three minutes. No slippery grass, dew or white frost. This was convenient this morning, when I woke up at 04.35 CET and noticed, that the nightly clouds had mostly gone, and the nearby street lights were still off. With the 18mmf/82° Maxvision, giving a TFoV of 0.72° and 114x mag, I started eight minutes later with M 35, already deep to the west. It's stars filled the whole field of view. More fascinating was the nearby oc 2158, a very remote cluster (16500 Lyr). It was well resolved into tiny 13 and fainter mag stars - a really "stardust"-impression, and aesthetically very pleasing. Over to the Leo triplet, M 65, 66 and NGC 3628. The former two showed readily as oblong 3:1 galaxies, and the fainter 3628 revealed even the slightly asymmetric located central dust line. All three were in the same field of view. The oc M67, again filling the field of view, finished the 15 minutes session, that was accompanied by two bright Quadrantid meteors (about -1 mag), heading south with rather high velocity. - The illuminated street lights (at 05.00) terminated the observation, but were helpful, when I pushed the scope back into it's at least temporary new housing. A nice and rewarding start of 2020; and so to bed for additional two hours of sleep. Thanks for reading Stephan
  9. 5 points
    I visited this area back in August and noted the Gylden Valley whilst I was sketching Ptolemaeus and others. At the time I noted the valley. This visit was centred on Gylden Valley itself. It has been hard to find information about it other than it is about 47km wide and is part of the Imbrium Radial Structure. It must have been an enormous piece of rock flying at low altitude as it gouged out this cleft. In the valley I caught site of longitudinal curving ridges. Crater Gylden, bottom left (southern) at the end of the valley. It must have occurred after the cleft was formed as it impinges on the valley. Gylden crater has been lava filled and interestingly so the central peaks are off centre. Crater Sporer impinges on the valley on the opposite side at the Northern end with no sign of a central peak. Below Sporer is Herschel N and to its West is the the big imposing crater of Herschel. Noting all the impacts in the area it is a wonder this cleft survives at all. Part of Ptolemaeus just sneaks into my sketch. Black is done in felt. Some of the white is gel pen. The rest is with a 4b graphite pencil and smoothed out with blending stump. Mike
  10. 5 points
    Alright, so I've had 2 nights that were clear and I had a chance to try the scope under the stars. Initially I am quite pleased with the performance of the scope. Not so much with the mount though, because it seems to be causing vibrations that gives an image that appear to be affected by atmospheric turbulence. But the symptoms comes already at 100x, and the air was very cold the second night with little moisture. I was set up on our front yard which is compacted gravel, so a very hard surface, not very different from concrete, especially during sub-zero temps. I will try next time to set up om the lawn part of the yard instead, and see if it makes any difference in suspending vibrations. The vibrations also made it hard to focus on stars at high magnifications. But all in all I had very nice views. Yesterday was the longest observing session. Being out from 20.00 to around 00.45. I viewed the Orion nebula starting with low mag around 21x, then increased to 30x. The scope picked up the cloudy details very well, much more so than my 102 slt achro frac. I could see a very dark field in the image that stood out and was way darker than the surrounding darkness. As I went higher, this pitch black which I suppose is dust, grew bigger and bigger. And even at 100x, I could see the cloudy misty soft nebulosity extending in every direction. It was a very nice view and I spent a good 20-30 mins on that target. This was with a moon that was more than half full and drowning the sky in its glare. Could easily discern very tight stars that were very close to eachother. I also visited bodes and cigar galaxy. Had no problems spotting them in the scope at 21 and 30x. But the moonglare destroyed any possibility to see much of the extension of bodes galaxy. Had to use averted vision to see some more. But I think on a dark night, I will see more. Visited also the beautiful doublecluster. My eyes were quite watery from the cold wind that started to pick up, so had a hard time with the stars as they were glaring But did manage to get some fine views of pinpoint stars. I really like the doublecluster, and viewed it in 21x and 30x. I like the sea of stars around the two clusters that almost seems to spiral outwards. Visited some other clusters as well. The hyades amongst others, and I think M67 and a couple of others. Also I spent a good time looking at the moon, before and after viewing deep sky targets (stupid to look at the bright moon before, but I wanted the whole buffe..) I had good views up to 250x, so a little bit past the 50x per inch limit. Some color showed on the lunar limb, but it started already at low mag and did not increase with higher power. And it dissapeared completely when viewing directly on axis. And it came and went as I moved my eye. So this is lateral colors I am seeing. It was more pronounced in wider angle eyepiece I had. I used the following eyepieces last night: TS-optics 2" 70 degree 38mm giving 21x Celestron (plossl design) 1.25" 54ish something degrees 25mm giving 32x BST Starguider 1.25" 60degree 8mm giving 100x BST Starguider 1.25" 60degree 5mm giving 160x BST Starguider 1.25" 60degree 3.2mm 250x and a damn small exit pupil Attaching a singleshot taken with Samsung S7 through 5mm eyepiece at 160x (just holding it at the eyepiece). The image is low detail (uploaded to facebook via phone and then downloaded from there to my computer) but still a pretty nice shot. You can see some of the lateral colors though. I don't like to use moon filters. I like it as it is, unfiltered. But when I came in, I had a glowing green moonghost in the eyes for a while, felt like I had been staring in the headlights of a car Gotta read up on the geography of the moon, it has pretty interesting details. I really like this mountainridge in the center of the picture, extending as a half circle. Mare Imbrium, perhaps? Best regards Peter
  11. 4 points
    Went out at 8.15 pm when I saw indications there may be a thinning of the cloud, and stayed out until 8.50 and managed some glimpses of the Moon when the cloud broke near the Moon briefly. I was pleased I bothered as the 'Cup Handle Effect' was visible. This is when the Jura Mountain tops are catching the morning sunlight, but the sunlight has not advanced across Sinus Iridium far enough to reach the base of the mountains. This has the effect of making the Jura Mtns look rather like a cup handle clinging to the edge of the terminator. Took a single frame at 8.45 pm, SW 80ED, AZ5, Olympus E-M5 Mk11, 1/25 sec at 400 asa.
  12. 4 points
    Been running the Graves meteor detector over the past couple of days for the Quadrantids. Below are my numbers and graphs of results with, for me, a clear peak around 05.00-06.00UT on the morning of the 4th Jan. Regards to all, Les
  13. 4 points
    Against the odds, some clear patches developed between 4 and 4.30 pm and I managed a few pics before the cloud closed over completely. A nice lunation with the terminator running right through Copernicus and along the W edges of Clavius. Single frame taken at 4.66 pm, SW80ED, AZ5, Olympus E-M5 Mk11, 1/125 sec at 400 asa. Moon 64.0%, 9.46 days.
  14. 3 points
    Don't think this has been mentioned before - apologies if it has... Free 1-day Practical Astronomy show in Kettering? (21st March 2020) https://practicalastroshow.com/ A couple of the online talks from 2019 were quite interesting: SharpCap's Dr. Robin Glover on optimising exposure times (https://youtu.be/3RH93UvP358) + Damian Peach on high res. planetary astrophotography:- (https://youtu.be/3RH93UvP358) We're going to combine it with a trip to the National Space Centre in Leicester - should be a good weekend!
  15. 3 points
    I recently acquired a 102mm ed scope and having learned a lot from reading posts from others about their scopes thought I should share some comments on this one. I've observed previously with achromats, maksutovs, SCTs, and newtonians, but never an ed/apo. The headline specifications are: - 102mm aperture, 714mm focal length, focal ratio f7 - Air spaced ed doublet with fpl53 glass - 2.5" rack and pinion dual speed rotating focuser, with a retractable dew shield. This happens to be an Altair Astro Starwave 102ED-R scope. I believe you can get similar scopes from other suppliers, however my comments are intended to be more about this scope compared to my expectations and compared to other types of scope than about this scope compared to other 4" apochromats as I have not tried any others. I bought this as I would like to experience different types of scope for myself and in the hope that I can simplify to a smaller collection of scopes. In particular this scope is planned to be mostly grab and go in nature - potentially replacing both a Star Travel ST120 f5 Achromat and a Bresser MC127 f15 Maksutov. I will be doing some comparisons of these and it will be interesting to see how it goes... the ED102 has quality on its side but the ST120 and the MC127 have more aperture, lower cost, and are no slouches at what they are designed to so. Here it is with a typical set up I am using - just an RDF, a 6x30 RACI finder, and 1.25" diagonal and most of the time I'll probably be using light eyepieces (SLV's) or a MkIV zoom eyepiece. I don't use 2" gear on small scopes to keep the size/weight down, and with finders I've downsized from a Telrad and a 9x50 RACI also to reduce the size and weight of the kit I am using. I've started accumulating notes and will post some when I have sensible chunks of commentary to add - fingers crossed!
  16. 3 points
    Was driving my gran back home after a family get together and noticed the lovely sunset. Decided to go down to the beach and see if I could catch the Moon and Venus's reflection. Taken on my phone so resolution is not great. Tommy.
  17. 3 points
    My IC-342 project has come to an end. I felt this IC-342 deserved its own post, so I am posting this image out of respect for my friend Rick Kunts, whom provided half the data. I collected about 32.5 hours of data usinga TOA 130 with an ASI 1600, and about 32 hours of data was captured with a Planewave 12" CDk and a 16200 camera (not sure the brand). My data by itself can be found in my previous IC-342 post. Due to the scale difference, I registered all data to the red stack of the Planewave. this is an L((Ha)R(Ha)GB composition. the quantity of data yielded a clean image, much cleaner than my data alone, which, when enlarged to this size is obviously noisy. But, for some reason that probably nly Vlaiv could explain, my data was sharper than his--so I blended the final image with my original, which imparted its sharpness to the clean new image. I think this is about as good as i can make this data. I am not 100% satisfied of course--some of the faint outer regions seemed to have dimmed a bit-surprising with the amount of data--maybe its due to my processing. Anyway--this is my fist true callobration on data and I am anxious to try it again on a less "hidden" subject.
  18. 3 points
    Hi again! Yesterday evening I assembled LowSpec device - I still miss focusing bolt, so I need to focus manually moving the camera. And also spectroscope collimation is rough, for testing purpose. But first results are very promising. I have used all standard optics from LowSpec and 600 l/mm EO grating. I used Altair IMX224 camera. First test frame with workshop fluorescent lamp: Mosaic of full visual range: And plot from Vspec: Today morning I recorded few Sun spectra. Doublet Na: and magnesium triplet: I am pretty happy with this test results. I think after careful collimation and mounting focusing bolt resolution will improve a bit. Many thanks to Paul for this outstanding project and to Ken for constant support!
  19. 3 points
    We go for so long between clear nights that when we do get one we have to spend it getting things working again - even in an obs this happens. There's only so much equipment testing you can do without actually being under the stars. Suppose it's our own stupid fault getting involved and having a passion for this activity in the UK - rather like getting involved in white water canoeing in the desert and complaining there isn't enough rain to feed the white water.
  20. 3 points
    Good news! Mr. Mesu recommended checking the wire connections on the dec controller input. Some of them were loose!! Don't know why, the mount sits comfortably in the obsy, maybe thermal expansion/contraction? After I tightened the screws, I downloaded the latest sitech.exe (v95A) reinstall the software reconfigure the sitech.exe (took 2 minutes, after a while one learns it by heart :)) ) close sitech.exe position the mount with scope looking east open sitech unpark (ignore error message) issue an offset init somewhere in the east sky (too cloudy to sync on the Sun :)) ) the mount starts tracking no error, no sudden movement in DEC, fingers crossed. After 5 minutes of tracking with no error, open a bottle of champagne stop tracking slew manually to a convenient park position park set park turn off everything Spare your credit card from a 10 Micron 2000 hps :)) for now, and dream of CFF 185 mm APO After 2 years with the mount I still have stuff to learn. Some times I wish the sitech software was a little bit more user friendly Next order of businesses: when the weather clears I have to check the spacing between the FF and camera Thanks for the support! and specially mr. Mesu for his quick email response and troubleshooting!
  21. 3 points
    Hi Dave. I got back out on I C 443 around New year and the light leak is gone. Thanks to you and Vlad for keeping me right here
  22. 3 points
    Took this photo of Venus yesterday, it clouded up on my way to the lake Another shot with the moon on Dec 30th
  23. 3 points
    Better view than in Blighty
  24. 3 points
    At last the skies were clear and I’m off from work so I took the 130 out for my first look set the AZ pro up and fired it up it did it’s merry dance and started the alignment set up it used the moon as this was obvious to pick out and almost centered it in my 35mm Panoptic a few adjustments later it was all aligned I spent a fair while studying the image of the moon it was flawless and pin sharp the shadows in the craters were the crispest I’ve seen any scope I have owned and the whole image looked so clear and crisp I pushed the GoTo to Uranus it slewed straight to it showing a pale green orb disc so sharp then onto Neptune a beautiful blue disc appeared by this time M42 was coming round so Over to that we went again so sharp and detailed it seemed as though I was viewing through my TMB 152 all the stars of trapezium were there with ease did a star test perfect inside and outside of focus it truly is a wonderful scope to use and manage I understand now why these don’t come up to often on the used market it seems the 130 is a perfect balance of aperture to weight and matched with my AZ Pro a very portable set up really hoping for lots of clear nights now .
  25. 3 points
    I love my 8" Cat on GoTo, I love my Dob 'cos it's so easy to swing about the sky while grabbing lots of light, and I love my fracs on altaz - also very easy, but not as good as the Dob for high altitudes. Basically, I love 'em all! Doug.
  26. 3 points
    Arp 315 is a small group of galaxies in Lynx located about 300 million light years from our solar system. It is quite easy to distinguish on a night of good seeing because they are of magnitude between 11 and 14, Arp's notes: Companion E (NGC 2831) is quite compact. Chhallenge: Separate 2831 and 2832 TSoptics RC8 + Risingcam IMX294C uncooled+ Risingcam captura soft 15x25" stack+ DF&FF correction+ Startools post process
  27. 3 points
    I would never consider making an offer on an item unless I felt it was genuinely overpriced. I have had some insulting offers in the past for items and felt it was a real cheek and politely declined. One such person told me the item was overpriced (which it wasn't as I apply the 2/3 new price as do most others). He then approached me several weeks later to see if I had sold the item, I bet he was hoping I'd got desperate and would sell him at his cheeky price. I was then happy to inform him I had sold at the asking price. Carole
  28. 2 points
    Hi all, I'm doing an all sky camera (more heath Robinson). Managed to scrape the clear plastic dome whilst drilling. I'm hoping it won't have any detrimental affect on performance but I'll have to see. Can always order a replacement if needed. Cost £50 excluding the camera. It'll be based on the Zwo Asi 224mc which I had hanging around. I've also got a Zwo120mm so not sure to use that instead. It'll be interchangeable anyway which I end up using. I'm finding it difficult to get hold of a reasonablely priced 180 degree lens at the moment so any suggestions would be much appreciated. I tidy things up when I seal the dome with clear cealent. Also I need a 15m length of usb3 cable for the 224mc as against usb2 for the old 120mm. What software are people running on Windows 10?
  29. 2 points
    Jan 3rd was one of those steady transparent skies. In addition to my previous post I wanted to take a look at the crater Regiomontanus because it has an interesting central peak. True to form I got side tracked due to there being so much of interest in the area. I did have a close look at the central peak and yes there it was - a crater let right at the top of the peak. Then I spotted that there was a shallow valley running NE from it, down the Eastern slope. West from the cratered peak the slope is much steeper, resulting in a wonderful shadow. Further inspection revealed a minor peak to the south and a ridge running north. Then I started pondering why is the central peak not in the centre of the crater? I soon realised that the crater to the north, Purbach was younger and had smashed up and totally obliterated the original northern crater rim. Thus making the once central peak, now apparently an off set central peak. Looking at Purbach it looks like any central peak got covered by lava, then ridges caught my eye - remains of what must be ghost craters - just had to mark those on the rough sketch. And so it went on. What a cracking crater Thebit is, the one at the top of the sketch. In the end I just gave up - so much to absorb. I marked on key shadows and a few key details, deciding that I would have to rely on an image of the area to add extra details to my sketch. On the sketch I have done a circular inset to try to show the detail of the Regiomontanus central peak. Mike
  30. 2 points
    Here is an image I got this morning/ last night. This is about 6.5 hours of hydrogen alpha through my new 3nm 1.25in filter. Unfortunately the filter's rim is so thick that it got caught on the inside of the filter wheel however, I found a solution by reversing the front plate of the wheel so that it is inside out A bit odd but it works. So far moving to a narrow bandwidth filter looks promising, less light pollution and stars visible. Processing for this image is just a stretch and re sample. ASI1600mm FSQ106 Astrodon 3nm Ha: 55x430s Happy New Year
  31. 2 points
    Heya, Woke up to a fairly decent sky this morning without rain, been a while since we've not had rain daily, weird storms near Florida lately. Bleh! Anyhow, seeing was average to good at some moments. Took a peak at two noteable features, the new unnamed active region has visible umbra, likely to be named AR2755 I assume, the poles are that of cycle 25, so we are on 3 cycle 25 spots in a row in such a short period which is really interesting activity. The largest umbra shows a light bridge already, so it is already decaying and will not likely get bigger but rather diminish as it progresses I think. Still glad to see it. There is also a filaprom to see on the limb, North West quadrant that is nice! B&W: Colored: Earth Scale: Equipment: C8 Edge + Aries D-ERF Baader Red CCD-IR Block + PST Etalon + 10mm BF (Chromospher) Baader Red CCD-IR Block + 610nm Long Pass (Photosphere) ASI290MM 52mm F11 (ED80 masked) Baader Red CCD-IR Block + PST Etalon + 10mm BF (Chromosphere) Baader Blue CCD-IR Block + E.O 430nm (Photosphere) Very best,
  32. 2 points
    I’ve been recommending Sticky Stuff Remover for years.. Works and no nasty smells and it doesn’t harm skin. Works well on upholstry and clothes as well.. I recently refelted some rings with some of FLOs flocking.
  33. 2 points
    Only advantage 2" eyepieces offer is larger field stop. That means larger AFOV at longer focal lengths. In order to fit larger field of view / lower magnification in eyepiece you need wider field stop (surface at focal plane that lets light in - larger it is - larger field of view it will allow). At some point you simply run out of space in 1.25" eyepiece format - at about 27mm - you need a bit of space for eyepiece body and filter thread and soon you are at 31.5mm - or 1.25". To circumvent that - eyepiece makers use 2" format. Some 1.25" eyepieces have 2" "converter" - it is just fitting so you can use them with 2" focuser / diagonal - it is essentially the same thing as you already have in your focusers / diagonals - 2"-to-1.25" adapter - just a piece of hardware used to hold EP in place - it does nothing optically. In any case - don't choose eyepieces based on 1.25" / 2" format. Eye lens will be larger if eyepiece has larger AFOV (apparent field of view) and longer eye relief. If you like eyepieces with larger eye lens - you could be in fact liking eyepieces with longer eye relief. These are often described as more comfortable to use as you don't need to get in too close with your eye to use it. Too long eye relief can also cause problems, especially on smaller exit pupil - it can be hard to hold your eye properly positioned and you can experience blackouts because of that. Anyways, here is my list of EPs that should suit your scopes good, provide you with what you want and cost less than TV or Pentax: budget: BST Starguiders Upper tier: Explore scientific 68 degrees and 82 degrees series (I can recommend 5.5mm 62 as well - managed to finally try out mine and I like it). Top tier (close in prices to two mentioned brands but not quite that level): Baader Morpheus I think that you can safely go with ES 68 / 82 but be aware - that will depend on how much you value eye relief. While ES eyepieces do have longer eye relief - It is not always as comfortable as can be - for example 82 degrees 11mm and 68 degrees 16mm - although they have 15.6mm and 11.9mm eye relief respectively in their specifications - in use they feel about the same in terms of eye relief - on edge of comfort that long eye relief provides.
  34. 2 points
    Nice all sky set up there, I run my 120mm-all sky via wifi on stick pc with fire capture on it to laptop inside via windows remote connect. What I like about fire capture time lapse mode is will turn off pc when its finished / before dawn. So for meteor shower evenings I connect and watch live while it captures or disconnect while it captures, watch tv, connect again, disconnect, forget about it go to bed since it will shut itself down.
  35. 2 points
    Main idea is to create affordable setup that can "do it all". I noticed that many people come and ask for advice for a scope that can basically do it all - as they often put it: "I want to observe both planets and deep sky objects, and I want to be able to record what I'm seeing - to take a picture of it". Some give a bit better explanation of what they want to image - but point is - they are limited in budget - usually up to 1000 of dollars/pounds/euros (I guess it is mental barrier of four figures spent on gear). Of course - you can't accomplish that in said budget or with one scope, but I wondered if one is ready to cut some corners - what sort of setup it would require and what sort of budget would cover it. Since I already own some bits and pieces of such setup, and I fancied idea of having a small Mak as grab&go lunar scope - I got myself new setup for both purposes - to test out "do it all" budget scope and to have lunar scope for quick peek. In lunar role - this scope is beyond my expectations. Mount works good enough to track the target and hold the scope. Setup is less than a minute, and scope delivers sharp views beyond x200 power. What more does one need for grab&go lunar? In the mean time - I'm fiddling with EEVA with this setup as that is the key for "do it all". It will aid observing in light polluted areas, but it will also provide base for "take image of DSOs" that I see (well they will see them when doing EEVA). In order for this scope to be good performer for EEVA - we either need large sensor ($$$) that will provide large FOV or if we go with small sensor CMOS camera that will be both for planetary imaging and EEVA/DSO imaging (and cheap) - we need means to exploit all corrected and illuminate field that scope is providing - that means some sort of focal reductor. We also need quite aggressive reduction if we want to get widest field possible out of this scope (and make a good match in resolution vs pixel size for available cameras that have pixels in range of 2.4um to 3.75um). I've identified 4 different means to achieve focal length reduction: - EP projection in "reducer" configuration ( focal plane of scope is at sensor and eyepiece lens acts as focal reducer - see first post - I could not achieve this successfully because I could not get sensor close enough to eye lens of eyepiece with this adapter). - EP projection in "regular" configuration ( focal plane of scope is at focal plane of eyepiece and eyepiece is again bending - reimaging at sensor). I tried this approach today and while it works and you can "dial in" required/wanted reduction - edge correction is disastrous - there is so much blurring at the edge of the field. - Regular reducer - very limited choices there given that most reducers are T2 or 2" and we have 1.25" option only here (maybe I could look for T2 reducer?). This seems to give most usable results so far. - Afocal imaging. This uses eyepiece the way they are meant to be used - focal point of telescope is at focal point of eyepiece and eyepiece produces collimated beam at exit pupil. Lens is then used again to focus that light onto the sensor. This combination is the worst in terms of number of glass surfaces - but will potentially provide best correction / best sharpness because both eyepiece and lens will be doing what they are designed to do. Problem with that configuration is - attaching everything together and matching eyepiece focal length and lens focal length and getting lens that is good enough (there are a lot of security camera / industrial type lenses out there that match sensor size - but most are basic and not well corrected lens - usually marked as 2MP - for this application we really need sharp lens - marked as at least 6MP or higher - 10MP, and of course lens performance needs to match the label - and still be cheap / affordable). That is left to be tested and I'll test that as soon as I get lens to test with. This was rather long answer, short one is - we use EP projection as one way to get focal length reduction because we want wider field and better matching of pixel size to focal length with this scope and camera I'm using.
  36. 2 points
  37. 2 points
    My last image of comet C/2018 W2 (Africano) taken on 2019 November 17, when it had moving away until 1.8 AU from Sun and Earth its brightness had dropped to a magnitude near 13 with a very faint green coma some 3 arcminutes of angular size and a weak dust tail with 5 arcminutes lenght. Data and link to image: https://cometografia.es/2018w2-africano-20191117/
  38. 2 points
    Once Betelgeuse does go, it will be that bright I don’t think we’ll be seeing Orion at all for a while but to see the result will more than make up for it
  39. 2 points
    Hi everyone. Just a thought here, and if you don’t agree, that’s fine, I’ll understand........ As you know, there’s loads of used astronomy kit for sale, from various online sources. Much of it seems to stick around unsold for ages. I fully get that folks want to obtain the best price they can, so they can release funds for whatever. But the other side of that is we want to buy stuff for a great price for us. In a world awash with second hand stuff, it seems to me that there’s only one way to make our advert stand out and get it sold, and that’s with a lower price than we would really like to get. A lower price will hopefully bring a quicker sale. I wouldn’t want to see “a race to the bottom” we want a fair price for both sides to the deal. A “fair price” is of course a matter of opinion. Several years ago many said that a fair price was around 70% of the new price. Much more than that and most would say it’s better and safer to buy new, with a guarantee, and with many dealers the option to return for a refund. It could be I’m biased. Being retired for a long while, no mortgage, no debts and adequate pensions ( worked hard for them !! ) I’m financially stable. I realise that lots of you are not so fortunate, lots of bottomless pits for your money, and many desires you’d like to own, so it’s a struggle. So feel free to agree or disagree ( nicely please ) to the above regarding lower prices and kit unsold as a consequence of higher prices, or shoot me down in flames if you wish.......... Cheers from Ed.
  40. 2 points
    Wow fast mover!!! A lesson in decision making!!
  41. 2 points
    Well..... I wasn’t going to get a jumpstart pack but for 50 quid I can’t complain. You sold me on it There is a Halfords five minutes down the road so I got one just now
  42. 2 points
    Please don't Gina, I'm not sure my blood pressure would benefit
  43. 2 points
    Not intended to drink huge quantities of alcohol and feel terrible for 48 hours, I went down to Beadnell Harbour and took a few snaps. Alas, the clouds were coming in. Frost was forming on my fingers. It was windy..... and there was an industrially sized arc-light behind me. Still.... Stitching programme had trouble matching the hugely contrasting light levels between the Sky and the local artificial supernova. You can see it with a kink in the harbour wall, but hey-ho I think I got away with it. Btw..... HNY....as they say.
  44. 2 points
    If what's under the concrete is stable then I see no reason for it to crack without the need for fibres or any other additive. If it isn't stable then the concrete will probably crack (or at least shift) eventually regardless of what you put in it. Here the soil is quite shallow and I can get down onto rock very quickly. Even my 7.5m x 2.5m brewery barely has 150mm of concrete in the base and that isn't showing any sign of failure. If you have deep topsoil though, I'd probably think about putting a load of hardcore into the hole first, tamping it down and then just lay concrete for the top 100mm to 150mm. If you don't intend to be in the observatory bumping into things whilst imaging then I'd not worry about a large block for the pier. The entire base will effectively become your large block. James
  45. 2 points
    I poured my dome base in one hit during last summer’s heatwave. Six inches of concrete + pier hole which was 800 wide and 600 deep. I’ve had no issues with cracking, however I did water the concrete 3 times a day to stop it from drying out to quickly.
  46. 2 points
    Together with my son Steven busy grinding the optics for this telescope.
  47. 2 points
    In this image I think you've black clipped it so much that none of the rotating noise of the first one would be visible anyway. Some field rotation remains visible in the stars, though. The only defence against field rotation with an alt-az mount is to shoot short subs. (Actually no, you do have the option of relocating to either the north or south pole... ) If you're feeling diligent and have Photoshop there is a simple software dodge for making stars round. Saved as an action it can work quickly but only on one star at once. Your action, saved to a function key, should record the following once the magic wand has been used to select a star: -Select, modify, expand (try 5), -Select, modify, feather (try 3). The chosen values depend on camera-scope specifics. -Filter, blur, radial blur set to best quality and spin. Run the filter twice. -Deselect. (Don't forget to record this.) Once done you magic wand a star and hit the function key. Voila, round star. Olly
  48. 2 points
    I couldn't help noticing that a few asteroids named after actors, characters or producers from the original Star Trek series are well placed in the evening sky at the moment. So I thought I'd try and capture them this week. The presence of high clouds and the nearby moon means that these are hardly pretty images, although at least they show the target in question! These were all captured with my Atik 428ex and 200mm f/5 Newtonian. The positions were all verified by Astrometrica. First up is 7307 Takei, named after the wonderful George Takei, AKA Mr. Sulu. Still alive and kicking. This one is relatively bright at magnitude 16.8, and currently very near the Pleidaes. This is a stack of 5 x 120 second exposures. Here's an animation of the first and last images, showing the slight movement over the period of about 10 minutes. Next one is 68410 Nichols, named after the equally wonderful Nichelle Nichols, AKA Lt. Uhura. Also still with us. This one is very dim at mag 19.3 and only just visible in this stack of 27 x 60 second exposures binned 2x. Currently quite near Takei in Aries. This one is 2309 Mr. Spock, a 16.3 magnitude asteroid in Cetus. 20 x 60 second exposures. The story goes that the asteroid was named after the discoverer's cat, Mr. Spock. But since the cat was named after the original Mr. Spock, then I will assume that the asteroid was too! I did try and capture 4864 Nimoy, named after Leonard Nimoy AKA Mr. Spock and currently in Aquarius, but it was close to the moon and at 18th mag. was washed out. This one is 4659 Roddenberry, named after the creator of it all Gene Roddenberry. Magnitude 18 in Pisces. 20 x 60 second exposures binned 2x, and stacked on the asteroid hence the star trails. There is also an asteroid Shatner, currently in Gemini. Sadly, none of the other original stars have asteroids named after them. There's also one named Tenagra after a place in one of my favourite Next Generation episodes: 'Darmok'. OK. That's enough nerdy stuff for the time being.
  49. 2 points
    Here's my first attempt at M42 with a 70-200 f4 lens (at 200mm) from a bortle 4 zone. f6.3, ISO 800, 45x90" lights, no flats (I completely forgot, therefore it was necessary to crop the image drastically due to dust particles on the sensor) stacked in DSS and processed in Startools. I am going to shoot this again soon aiming for more integration time, hoping to bring out some dust.
  50. 2 points
    My used price baseline is 60% of new, not 70%. I don't ask more than that, or pay more than that, without very good reason. Most of my kit has been bought that way as well, despite its being used professionally. I have an advantage and disadvantage as a seller in that, as an astronomy provider, I would be mad to sell bad kit to anybody since it would hit my reputation where it hurts. Like anyone else I have, on rare occasions, ended up with bad kit (not because it was second hand but because it was just bad, or way over-priced. Tak EM200 mount bought new. Ouch. Never again.) In these circumstances I either give it away or sell it, fully declared, at very low prices so that nobody will accuse me of dishonesty. That's the down side of my situation. The plus side is that people know this, so when I offer kit for sale they know they can rely on me and I generally sell - quite seriously - within half an hour. I'm not joking. The father of my childhood best friend was a nationally famous antique dealer. He had a rule that he never made offers, he either accepted the asking price or rejected it. He never gave valuations and bought at the same time. (How can you make an honest profit if you do that?) I think these are good principles to follow within our community, for that's what it is, a community. I've never had a bad experience buying second hand. The few bad experiences I've had have been when buying new, truth to tell. Olly
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