Archived posting to the Leica Users Group, 2020/12/21
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]My preference for detail is the narrow bandpass picture, because you can see the filamentary structure. However I prefer the contrast in the first stacked image. In the second you can also make out the motion of the stars between frames. Funny that, because you have more images stacked in the first than the second. I assume that the narrow filter meant longer exposures per frame. Is that right? Peter On 21/12/2020 15:05, Howard Ritter via LUG wrote: > Hi, Peter? > > The images are single exposures. Since posting them, I?ve learned how to > stack multiple images of the same field to improve S/N and reduce color > noise and granularity. It makes a huge difference! > > I?ve just posted > <http://gallery.leica-users.org/v/hlritter/Nikon+Astro/?g2_fromNavId=x98ac3343> > a stacked version of the same Orion field as well as a stack of frames > taken through a narrower emission-line filter. The latter I think is my > preference. > > http://gallery.leica-users.org/v/hlritter/Nikon+Astro/?g2_fromNavId=x98ac3343 > > <http://gallery.leica-users.org/v/hlritter/Nikon+Astro/?g2_fromNavId=x98ac3343> > > ?howard > >> On Dec20, 2020, at 1250, Peter Dzwig <pdzwig at summaventures.com> wrote: >> >> Howard, >> >> are those single shots, or did you stack them? The one of the Orion >> nebula is particularly fine. >> >> Peter >> >> On 19/12/2020 21:38, Howard Ritter via LUG wrote: >>> Congratulations, Douglas. A first astronomical telescope is a memorable >>> and possibly fateful thing, potentially a trap as dangerous as a first >>> camera. With me it went the other way: At about age 10, my parents got >>> me an Edmund Scientific 3? reflector, and this was enough to launch me >>> on a lifelong hobby. I got my hands on a camera at about the same age. >>> It?s a tossup which hobby has consumed more of my time as well as money! >>> The apex was a 25? Dobsonian (I?ve downsized to a mere 20? now, plus a >>> 6? refractor and a pair of 100mm astronomical binoculars.) >>> >>> The Dobsonian format is the ideal one for a neophyte, and a 6? aperture >>> will show you wonders. I recommend getting a guide to the Messier >>> objects, of which many look great in 6? of aperture, as I know >>> firsthand. And you won?t need to be told to point your scope at the >>> Moon! Dobson was a creative genius and the patron saint of amateur >>> observers around the world, a tireless advocate of astronomy on the >>> cheap for the masses. >>> >>> Good luck with the weather next Monday. Ours in Florida looks >>> unfavorable. Because of that, I took the time to get a picture of the >>> pair last night, when they were still 4 times as far apart as they will >>> be on the 21st. After moonset, be sure to have a look at the Northern >>> Hemisphere?s deep-sky (as opposed to Moon and planets) showpiece, the >>> Orion Nebula. If you don?t have dark surroundings, take a dark cloth or >>> hoodie to shut out all extraneous light as you look at the nebula and so >>> you can keep both eyes open while you look. Start with an eyepiece that >>> will give you about 50x. >>> >>> I put my images of Jupiter and Saturn, as well as the Orion Nebula, on >>> the Gallery here >>> <http://gallery.leica-users.org/v/hlritter/Nikon+Astro/>. >>> >>> http://gallery.leica-users.org/v/hlritter/Nikon+Astro/ >>> <http://gallery.leica-users.org/v/hlritter/Nikon+Astro/> >>> >>> ?howard >>> >>>> On Dec19, 2020, at 1326, Douglas Barry <imra at iol.ie> wrote: >>>> >>>> This is the telescope I got recently as a birthday present from my >>>> sons. It works extremely well, even in light polluted suburbia. I >>>> haven't taken it out to darker skies yet due to the pandemic. >>>> >>>> http://gallery.leica-users.org/v/DouglasBray/Sky+Quest+Dobsonian.jpg.html >>>> >>>> With the conjunction of Jupiter and Saturn coming up on Monday, I hope >>>> it won't be too cloudy so that I can use this. It's pretty good for a 6 >>>> inch, but with my back bothering me at the moment, I could with >>>> lightening the Dobsonian base a bit without sacrificing stability. >>>> Maturer years don't like heavy weights. >>>> >>>> By the way, if you would like some marvellously therapeutic viewing >>>> have a look at the great John Dobson making a reflector telescope by >>>> hand, including hand grinding and polishing the 16 inch mirror. >>>> https://www.youtube.com/watch?v=snz7JJlSZvw >>>> >>>> Douglas >>>> >>>> >>>> >>>> _______________________________________________ >>>> Leica Users Group. >>>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >> >> -- >> >> Dr. Peter Dzwig >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > -- Dr. Peter Dzwig