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knightware2

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About knightware2

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    North Carolina, USA
  1. Hi Captain, Very interesting experiment. I hope you can continue a bit longer before the summer time brightness interrupts. As regards the outlier readings... As I understand it, the meter continuously integrates data. The darker your sky, the longer it takes to integrate a reliable reading. Depending on how long you point the meter at the zenith, your first reading or so may definitely be statistically 'bad'. I hope that makes sense. Anyway, an average of multiple readings is a good idea, and outliers are a possibility. I hope you'll post here on your progress. - Phyllis
  2. I was there both days, but I haven't attended in the past. Saturday was busier than Friday. The crowd grew noticeably when a talk was over. My stand stayed busy Saturday afternoon and intermittently on Friday and on Saturday morning. Some vendors I spoke to said that business was not good, but others were happy. One thing for sure - the gentlemen running the show are delightful to work with and really want the show to succeed. All in all, it was a very worthwhile experience even with the plane fare from America. - Phyllis
  3. Hi heliumstar, Full disclosure - I am a vendor - husband and I will be attending IAS from the US. Our discount will be a shade higher than 10%. Please introduce yourself if you come by our stand (#9). I always enjoy meeting fellow astronomers at these shows! - Phyllis
  4. Yes it does. It covers the entire sky, and is perfect for small telescopes and binoculars. You can read about the smaller version here: https://www.shopatsky.com/pocket-sky-atlas , and the larger version here: https://www.shopatsky.com/jumbo-pocket-sky-atlas Assuming that you can get either version, you should be happy with this depth of sky coverage until you either learn the sky well or need charts for a darker sky or large telescope. They are wonderful charts.
  5. Hi Buzzard - I'm also from NC (near Raleigh). Welcome to SGL - it's a very friendly bunch. I'm glad you've got a new scope to kindle your interest. Better yet that your daughter is interested too. Please show her Jupiter now, and Saturn as it reaches evening apparition in late summer. I still needle my kids to have a peek (they are grown). Feel free to visit the Raleigh Astronomy Club if you wish - raleighastro.org. Let us know who you are and I'll be sure to say hello if I'm present. - Phyllis
  6. I have a copy of 'NGC 2000.0' edited by Roger Sinnott, published 1988. While it lists all the NGC and IC objects, it doesn't contain pictures. The question earlier about the number of objects might seem confusing. The NGC catalog has 7840 objects, and the IC (a later supplement) has 5386. Together there are 13226. More recent work on these catalogs has produced a larger number of objects only because some of the original objects have multiple components identified. For example, 2 components have been identified for the galaxy NGC 67 leading to NGC 67A and NGC 67B. 'NGC 2000.0' is a nice, compact listing of the catalogs, but 'Observing and Cataloguing Nebulae and Star Clusters' by Dr. Wolfgang Steinicke, published in 2010, is truly definitive. It explores the history of the catalogs and include pictures of a few (but not all) objects. This is a hardback book that is really expensive in the US. Maybe it is more reasonable in the UK. The internet is probably the best resource for pictures of all the objects although I don't know of a site that has photos for all objects. You can certainly query the online DSS websites for photos, but they aren't organized by object number. I wish you luck with this endeavour! - Phyllis
  7. Chris, Measuring seeing is mostly a subjective matter for amateur astronomer, but as a previous poster mentioned, it can be done objectively using a CCD camera. There is a very thorough discussion of measuring atmospheric seeing here: http://www.handprint.com/ASTRO/seeing2.html I believe that the most commonly used (subjective) seeing metrics used by amateurs are: Antoniadi scalePickering scale (see excellent examples at http://www.damianpeach.com/pickering.htm)Double star separation methodSeeing can change according to the area of sky being observed, so the measurement should be made in the area of interest. In practice, measuring at the beginning of an observing session after optics have stabilized thermally is perhaps more practical. As others have pointed out, SQM measures sky darkness. There are other metrics for sky darkness, but SQM is the objective one. Lastly, one might measure sky transparency. The only objective measurements I know of for transparency are Particulate Matter (PM2.5), and Aerosol Optical Depth (see http://www.gmes-atmosphere.eu/d/services/gac/nrt/nrt_opticaldepth/)
  8. I remember sharing views of Comet Halley with my mother and grandfather (who saw it as a child). That is a very special memory, and I hope yours means as much!
  9. I should try Astronomy Now again soon. I met some of the staff at NEAF in New York and they were fine folks indeed. I've had the good fortune to meet staff from Sky At Night, Sky & Telescope and Astronomy. They are all terrific folks - energetic, knowledgeable and so easy to talk with. Attending trade shows allows one to meet these folks and that is one of the reasons I enjoy going. To the original poster - please pick up a copy of other magazines before changing your subscription. We are so fortunate to have so many fine publications, and each addresses different niches.
  10. I have a little different view of the magazines (I'm in USA). I've subscribed for years to Astronomy and Sky & Telescope. I stopped reading Astronomy for several years, but resumed recently. I also read Sky At Night monthly, and I've read a few issues of Sky News (Canada) and Astronomy Now. All the mags have a different feel to them, and they obviously have different columnists and contributors. To me, we are very fortunate to have such a wide selection. I think readers should subscribe to their favorite(s) and purchase some of the others occasionally just to see how they fit in to their own interests. My own thoughts on the mags: I've read S&T for many years and I'm very concerned about 3 editors having left over the last 3 months. I hope the new owners take care of business. Astronomy has improved greatly in the past few years. I have a little trouble with the small font used for print, but I really enjoy reading it monthly. Sky At Night has become a definite monthly read. I think the artwork is excellent, and the coverage of current science is more readable than the similar sections of Astronomy and S&T. I have a friend that is a theoretical physicist who votes Sky At Night his favorite, and he reads everything mentioned in this thread. I think the take away is to try as many as you can, and subscribe to your favorite(s). Enjoy your astronomy reading whatever it may be!
  11. I really am sorry you guys are having to wait so long. I've had mine for a couple weeks now, and I am truly enjoying it. I've tried many eyepieces with the Quark in a 80mm f/4.8 Brandon refractor, and I've found a (borrowed) TeleVue 32mm Plossl gives the best image. It gives a full-disk view that is extremely sharp and contrasty. I tried to buy the 32 off of the owner to no avail. Can you guess what's on my Christmas list already? - Phyllis
  12. Michael - We have had some clouds here this week, so I appreciate your concern about tuning delays. A friend with a different DayStar filter suggested that tuning towards red might take less than 10 minutes, especially in summer heat. I experimented with this today but I did not find it to be true with the Quark. Tuning toward the red one click (.1 angstrom) still took about 10 minutes for the indicator on the Quark to change from orange to green. Views today were quite nice during periods of good seeing. Proper tuning definitely make a difference in the contrast of surface features. Observing at 52x revealed granularity, sunspots, plages, a large filament and beautiful prominence detail. Spicules were more difficult today due to lower magnification. - Phyllis
  13. Olly - Thanks for emphasizing the usage warning. I had a long talk with the DayStar marketing director at NEAF in April about my intended use and whether additional filters would be needed. In my case, I have air spaced doublets, each 80mm in aperture. No extra filter is needed and we have not used one. We also have a 4 inch Genesis refractor. It has a fluorite element midway down the tube, and that one needs a front ERF. We aren't using that one at the moment. I can say that we have observed for 30 and 45 minutes with each of our 80mm refractors this week and there has been no extraordinary heat build up in the filter or the front elements. - Phyllis
  14. I tried the Quark in another telescope. This time we used an 80mm f/9.4 refractor on an equatorial mount with the 32mm Erfle (101x). We started out with the Quark tuned to 2 clicks toward the blue. This is where we left off the previous day with the other refractor. It took a long time to find proper focus. The first diagonal (2") we tried did not allow sufficient in-travel. We found success by using a 1.25" diagonal and centering the limb of the sun on the cross hairs of a 12mm reticle (guiding) eyepiece with white light filter. Once the telescope was aimed properly, we inserted the Quark and the 32mm Erfle and saw much greater detail on the limb than with the lower power combination the day before. The views were stunning. With the longer focal length telescope (750mm), not only was magnification higher, but exit pupil was narrower (0.8mm), making eye placement a greater challenge. Viewing in daylight also means a more constricted eye pupil than with nighttime viewing, so care must be taken! The views with this equipment was very different. The surface detail was less impressive, perhaps due to etalon tuning. Limb features (prominences & spicules) were better. Even though surface granularity was less obvious, filaments were still very clear. We observed mostly with etalons tuned 2 clicks toward blue, but we changed to a further click toward the blue (a total of .3 angstroms) and noted very little difference. I think viewing with the longer focal length instrument is best for prominence detail. I also feel that we need more experience with tuning etalons to the optimal wavelength. It may be that working with either instrument is equally satisfactory once we learn more about tuning, but the smaller instrument can go on an alt-az mount, so it is easier to set up. Now we are waiting for clouds to go away. Maybe more viewing on Saturday! - Phyllis
  15. While the Quark is not an eyepiece, I suppose this is the most appropriate part of the forum for this report. Perhaps it can be moved by a moderator if necessary. I received my Quark chromosphere model Ha filter today from DayStar. Husband and I were fortunate enough to get a look at the sun for about 45 minutes before storm clouds arrived. Packaging was secure and the filter arrived safely without damage. Fit and finish were quite good and all parts were present. Importantly, the documentation included with the filter was concise and well-written. First light occurred through an 80mm Brandon refractor. Its focal length is 385mm (f/4.81). We observed during the hottest part of the afternoon, so there were thermal issues with the atmosphere. Apart from the occasional clouds and thermals, we were able to catch some very nice views using an old Celestron 32mm Erfle (52x) and an old TeleVue 24mm Widefield (69x). Both eyepieces had 1.25 inch barrels. It took the Quark about 10 minutes to reach proper viewing temperature at its center tuner setting. Initial views at 69x were very nice though the contrast seemed a bit light. A few curious neighbors stopped by to have a look which we enjoyed sharing. A few prominences, filaments and plages were visible, and a few small sunspots that were visible in white light were also visible through Ha. We switched eyepieces, giving a full disk view at 52x. We also moved the filter tuner one click towards the blue. This change also took around 10 minutes to reach proper temperature. The contrast was improved, and more prominences became visible. The general surface texture, filaments and plages became more apparent. A further change to the filter setting toward the blue resulted in yet better contrast at 52x. All features noted above became clearer with improved contrast. We plan to give the Quark another go through a longer focal length refractor as weather permits. Our next test will be with an 80mm Stellarvue refractor of focal length 750mm (f/9.4) with the eyepieces mentioned above. Items often debated online... You can definitely see surface detail AND prominences with the chromosphere model of the Quark.You can definitely observe without a front energy rejection filter on an 80mm refractor. The OTA and diagonal remained at reasonable temperatures throughout observing.You can definitely observe without a UV/IR cut filter on an 80mm refractor. Equipment temperatures remained reasonable.It definitely takes several minutes for the filter to reach operating temperature - either at start up or when the filter's tuning setting is changed. Fortunately, there is an LED on the filter that changes from orange to green when the filter has reached proper temperature.You can get very good views with eyepiece designs other than Plossls. Both eyepieces used so far are essentially Erfles. Further, at NEAF in April, I observed through a small refractor (size not known, but I believe 80mm) + Quark + TeleVue 24mm Panoptic.My initial impression is that the Quark delivers very good views with equipment we have on-hand. Because it can be used with our existing equipment, it is the most cost-effective Ha filter solution available to us. Further experience with tuning should result in excellent, contrasty views of the sun. - Phyllis
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