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Nyctimene

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Everything posted by Nyctimene

  1. I've read somewhere, that a DIY modification was done by replacing the three wood screws, that fix the vertical part of the mount to the circular one, with cylinder screws, and threaded inserts in the vertical part. With this modification, all the mount's parts fold nicely flat, and could be taken, together with the OTA, as hand luggage. Might be worth a try, if you have some woodworking skills. Stephan
  2. Hello and welcome from a German stargazer. A decent 10x50 is the stargazers "Swiss army knife", well suited for a lot of wide field views, and an excellent grab and go tool. Have a look at the Auriga clusters M 36, 37, 38; the Pleiades, M 35, the Orion nebula. Download the monthly newsletter. by BinocularSky ("Observing - with binoculars"). Enjoy the journey! Stephan
  3. Nice report. Nothing beats a big dob under decent skies. Worth all the hassles with setting up, using a ladder, small field of view etc. Just being out visual only, the right thyme and plaice (thanks, Peter!) - enjoy your great lifetime scope, and keep on posting! Stephan
  4. Had the same impression this morning at 0h30min CEST under 5 mag skies with the 13.1" Odyssey. Dimmed about 0.5 mags, and the coma diameter seems to be having shrinked as well to 4-5 arc min (but compromised by upcoming haze). Otherwise little change. Clouds rolled in after 15 mins, so I had to stop the search for pn NGC 246, the Skull nebula, well placed at this time. Stephan
  5. Spotted comet P/2018 W2 Africano this morning at 02.30 CEST under 5.0 mag skies with the 5.1" Heritage. Appeared rather faint, about 9.5 mag guesstimated; round, DC=4; coma diameter about 8 arc min. For moments, the "false nucleus", somewhat asymmetric positioned, could be made out. No tail visible. Rather fast movement, visible within 20 min. Incoming clouds, so no further investigation possible. Some fun, always escaping the clouds, with Castor, M 35 and oc 2158 (the latter slightly brighter than the comet), the Auriga Messiers, finally 7789. 26mmf ES; Seben Zoom. Stephan
  6. Interesting question, Gerry. I've been observing with binos and scopes for almost exactly fifty years now, starting with comet Bennett in spring 1970. But there have been many years with only few observations, up to ten/year. The frequency increased with my first Dob, the 13.1" Odyssey, that I bought 1987, having moved a few years before to a very dark location in the deepest Odenwald forests. Numbers climbed to 30 - 40 observations. After retirement, I was able to observe a lot more - up to three digit numbers in 2017 and 2018 (this year, 59 so far). I'll try to get some medical/physiological information about the subject; never heard of it before. Stephan
  7. Excellent report, Neil. Whilst reading, I was with you at the eyepiece. You described the process of finding an elusive object very precisely. (Had similar experiences last evening, locating NGC 891 under 20.6 SQM-L skies...) Stephan
  8. Definitely too big and heavy- moreover, 2" barrels, that won't fit the 11/4" Heritage focuser. I'm quite pleased with the 26mmf/62° ES LER eyepiece when working together with the Heritage. It's somewhat of an Erfle type; very good colour correction, very sharp on axis, slightly deteriorating at 85% of the AFoV. No kidney beaning; calm, relaxed viewing. If you are interested, here a review: https://www.cloudynights.com/topic/579467-26mm-es62-observations/ Stephan
  9. It does, indeed. With a Skywatcher UWA 6 mmf and the 2.25x Barlow, I get a 244x magnification - still usable for tight doubles (I can confirm Stu's Pi Aquilae split with it repeatedly), and Lunar. Stephan
  10. Another vote for the Skywatcher Heritage 130 P Flextube. It fits nicely into the boot of my Seat Mii (= VW Up), still leaving enough room for eyepiece case, maps, a small folding stool and some luggage. It's my grab-and-drive set at the moment. With an ES 26mm 62 degrees LER, I get a field (TFoV) of 2,5 degrees. Add a 24-8 Seben/Celestron zoom, and a shorty Baader Barlow 2,25x (giving 183x magnification), and you're prepared for all astronomical targets. Cheap enough, so any damage/loss will not harm too much. Added a picture of it in the boot/trunk of the tiny Mii: and another one, with folding stool, PSA, 7x50 binos, eyepiece case (re-, upcycled physician's case). Still enough space for other things. Stephan
  11. NGC 6811 in Cygnus, "Hole in a cluster". About 1000 stars, with some concentration in the outer regions, thus leaving the impression of a darker center - the hole. View varies with different apertures.; nice to look at and easy to find. Stephan
  12. Just to remember....posted this 9 months ago - a proven method to assess eye pupil diameter: It's really simple! Get a set of spiral drill bits, graded in 1/2 mm steps. Go outside (your pupils will adapt within a few minutes, not so the retina), and look, one eye covered, at a bright star. Hold, beginning with about three millimeters, a drill bit (blunt side up), 15 to 30 cm in front of your eye (you may as well go farther away with it -stars send parallel light rays out of infinite distance). You will see the starlight, passing the bit's edges and entering your eye. Now, work your way up to larger bit diameters; you will still see the starlight. At a certain point, the used bit will block all the starlight, and the star's image will have disappeared. Repeat two or three times; the bit's diameter just below the occluding bit is the diameter of your maximal dilated pupil. Now test the other eye. I've assessed for my eyes 6.5 mm (left eye) and 6 mm (right eye) that way - very satisfying at age 66. It's astonishingly precise, when repeated. Learned this from an article by German amateur Uwe Pilz years ago. Stephan
  13. Observing faint DSO's, or details in brighter ones, is mainly a thing of contrast, i.e. a high signal-to-noise (S/N) ratio. A certain aperture given, the signal strength (amount of photons entering the eye) cannot be increased. So it all comes down to decrease the noise. There are external sources of optical noise, that can be eliminated (observing hood/eyepatch, as you, Neil, already mentioned; observing late, in dark sky areas etc.). But there are also internal ones -the need of small muscular correction movements, when observing standing, contributes to the amount of neuronal "noise" in the brain. Therefore, observing seated is to be preferred. Alcohol increases via raising sympathetic nerve arousal neuronal noise in the same way; sleep reduces it. But in the sensors (=retina) and the processor (=brain) a certain level of "noise" is always present. There are several complex neuronal mechanisms, based on a combination of activating and inhibiting ("lateral inhibition") properties, that enhance contrast perception within the retina and the brain. Practice is also crucial; repeated activation of neurons in the visual system leads to the forming and growth of synaptic connections ("neurons that fire together wire together"), thus increasing the S/N ratio. In August 1997 I observed, together with the very experienced comet hunter, Otto Guthier, the comet C/1997 J2 Meunier-Dupouy through his 16". With a visual mag of 12.2 and 3 arc min coma diameter, we both could make out the comet easily, constant in AV, sometimes directly. Another experienced observer (but not so much in DSO's) tried it again and again, without avail. I learned a lot about the importance of experience that night. Stephan
  14. You might go up to really large apertures.... Dr. Erhard Hänssgens DIY Dobsonian, here shown with it's full aperture of 42". Here's the full read: http://www.cruxis.com/scope/scope1070.htm Stephan
  15. Besides astrophotograpy, an 8" f/6 Dobsonian is the stargazers "Swiss Army knife". Well suited for moon and planets, as well as for a lot of DSO's. Given your location in a less light polluted area, a nice lifetime instrument, not expensive, still portable to even darker skies to the west; have a look: https://www.lightpollutionmap.info/#zoom=11&lat=1143802&lon=8482192&layers=B0FFFFTFFFFTT Stephan
  16. Both feelings - the feeling of guilt, when not going out under clear skies; and the feeling of relief, when clouds come up, are quite familiar to me, even with > 100 observations 2017 and 2018. I've found, that a short session, even 5 to 10 minutes, can curb efficiently the feeling of guilt - at least for me, as a purely visual observer. 7x50 binoculars or a grab-and-go scope, as the Heritage, or a small frac, do it for me. Being out under the stars - that's the only thing that matters. Greek mythology tells, that the giant Antaios, son of Poseidon and Gaia (the Mother Earth), could never be defeated, as long as he stood on his mother, the earth. (Therefore, Heracles lifted him up and strangled him to death). I'm sometimes feeling as a kind of "reverse Antaios" - as long as I can look up to the stars and "dip my toes" into the Milky Way stream, I feel always strenghtened and regain confidence and positive attitudes. Even when it's mostly cloudy, I'll go out and try to get a view of some stars. Btw., double stars can be made out quite well even through thin clouds. Stephan
  17. Very congruent with my own list of showpieces. It's nice to demonstrate a sample of different celestial objects: moon, planets, open clusters (M 44/45; Owl cluster), globulars (always one on show), gaseous nebulas (M 42; North America nebula); Supernova remnants (M27/57; Veil). As galaxies go, M81/82 in the same field are always impressive (and different galaxy types). And don't forget double stars - Albireo; Alamach, Epsilon Lyrae. In winter, Omicron 2 Eridani (Keid) is a nice showpiece, as the triple system contains one of the easiest visible White Dwarfs. R Leporis ("Vampire star"), or La Superba as samples for coloured stars. When showing Albireo, I always ask, which colours the guest sees; then I lead over to star temperatures (glowing iron as a hint), then to the star's life cycle, and so on... So much to show! Stephan
  18. The "Red Eyes Cling Xtra Dark" is excellent, long lasting and, IME, worth every penny you spend on it. I've posted an update to a review of it a few days ago in the "Member Equipment Reviews" subforum on here. Don't skimp on the light shield - it will fulfill the needs. Stephan
  19. Just stumbled across a remark by the Deep Sky doyen Jon Isaacs of the CloudyNights forum, that he is using the same product ("General observing and Astronomy - Rogue observing", pg. 2, Aug. 23th). Prompted me to post an update about this product after two more years of use (about 290 observations with it in toto since October 2016). There is little to add. The light shield works still absolutely fine, despite some scratches, minor dents and slight delamination at the corners, which all cannot be seen when in use. Clinginess and flexibility remain at the default state. The light shield has become for me an indispensable item for all observations, as are the neck lanyard for my glasses and the dimmable red light torch. No hassle with the greyish LED backlight anymore, or with black letters on white flashing up when typing. For observers under 21+ SQM-L skies the best choice. Works best, when the SkySafari display is set to the "monochrome" mode. Very recommendable, and not pricey (5,95$) - have ordered three spare ones three days ago. (Of course no affiliation etc., just a very pleased owner.) Thanks for reading Stephan P.S.: ordered the Light Shield Sept. 04th; arrived today, Sept. 11th. No costs for shipping and handling etc.
  20. Was out from 01.15 to 03.00 CEST with the 8" f/4 Hofheim Instruments traveldob on it's newly acquired equatorial platform. Average conditions (NELM 5.6; SQM-L 21.12), good seeing, but some clouds, that interrupted the warming up with M 2. Remembering Nick's (cotterless 45) recent post, I went over to Iota in Cassiopeia, and found this lovely triple well resolved at 266x mag (2.6"/7.2"), the fainter components clearly more yellowish than the bright white primary. During the search, SkySafari had pointed me to a 12 mag planetary 30 arc min SE of my starting point, Epsilon Cas. I found this object, IC 1747, after a short star hop, and spotted at 200x and using a Baader UHC filter, a round, small (13") uniform disc, without details. Increasing the mag to 400x and using 4mm Ortho together with the Zeiss Abbe VIP 2x barlow, the disc appeared slightly elongated, and a brighter knot, in the direction of a field star close by NW, could be glimpsed now and then. The central star (15.2) could not be made out. - Two contrasting open clusters followed. oc 637 in Cas was easy to find, with a central elongated group of brighter stars, and fainter stars interspersed; very rewarding. oc 609, close by, was, in contrast, extremely faint, just an unresolved glow, visible only with averted vision. I finished, as usually, with my most loved oc, 7789, Caroline's Rose. Oh, and the joys of tracking! After five decades of observing, mostly as a Dobsonaut, without any electrical tracking (only manual tracked 6" Newton on a GEM), I was very pleased with the precisely working EQ platform. Changing eyepieces at high mags without losing the target - observing details in a planetary - splitting a double star comfortably - all features very welcome now with age. (But I would never give up the freedom of searching, and moving the scope willingly, that a Dob offers!). Really pleased with this mixed bag of observations and experiences, and so to bed. Thanks for reading Stephan
  21. 8 kgs in toto - it's aways fully built up, including RDF and light shroud, and I can take it out in one trip, as a real grab-and go scope. And all parts fit in the box with the handle, that serves as the ground board (with Teflon pads on it's top) - designed for airline hand luggage transport. The struts, made from selected beech wood, and joined with special hinges, hold collimation very well, even at f/4. I'm doing the star test every third or fourth session, and have to adjust the primary only slightly. The stability relies on many triangles in the construction; it serves as an example for the Hamburg High School for Applied Sciences (aeroplane and automotive constructions department). Stephan
  22. Yes, exactly; with it, this scope can handle 2" eyepieces. For real heavyweights, as my 24mmf/82° Maxvision (830 g - giving an excellent corrected TFoV of 2.5°, and an exit pupil of 6 mm), I just add a plug-on counterweight (available accessory). A second friction system on the scope's other side would be another option.
  23. Freshly arrived today; as it seems, I'm one of the first customers: after 11/2 years of developing time - the Hofheim Instruments equatorial platform (VNS-design). Seems to be well built, and matches the Hofheim design perfectly, as shown here with the 8" f/4. Their 12" f/5 will also work with it, not so the 16". (you can spot John L. Dobson's original signature on the facing upper folding ruler truss; obtained during his visit 2007 at the AME astro show). I guess, the Heritage 130P Flextube (here on it's removable "T" pedestal) will be pleased as well: Uploading Fingers crossed for a hopefully clear and almost moonless night! Stephan
  24. I'd suggest, if you get a free view of the southern horizon, to visit the splendid objects of the Milky Way- M8, the Lagoon nebula, M20, the Trifid; M 17 (Omega-or Swan Nebula), M24; M 16; the glorious globular cluster M 22 and, to the north, M 11, the Wild Duck cluster and many more smaller objects.For some of them, a UHC or O III filter will give the best views. Good luck with hunting them down! Stephan
  25. My first "encounter" with the crater-like structure Lamont March 8th, 2018, was so unimpressive, that I entitled my then post on here with "Lamont or How Not To Be Seen". Yesterday evening, the app LunarMap HD showed, that Lamont was very close to the terminator. At 3.00 CEST, I took out the 18" f/4.5 Obsession, and was very surprised, when, despite poor seeing (max. magnification 128x), Lamont gave a totally different view. A clear, oblong, crater-like shape, well detached from it's surroundings, the floor a bit uneven. Two overlapping lava terraces were extending from it to the north; a third and more prominent one to the south almost to the crater Sabine. The nearby crater Arago was flanked by two conspicuous lunar domes W and N (Arago Alpha and Beta, following Rükl, chart 35), forming with them both an almost equilateral triangle. The nearby Rima (rille) Sosigenes could be made out several times in moments of better seeing, extending from Sosigenes A to Ariadaeus E, and almost at right angles with the more conspicuous Rima Ariadaeus. An interesting area with a lot of different geologic formations. So, if you want to spot No 53 of the Lunar 100 and get a satisfying view, wait, until it is almost under the terminator! Thanks for reading Stephan
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