Forum Replies Created
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Posted by Tom Moran at 12:54 on 2010 Oct 19
Andrea.I know you are absolutely right. I just like refractors and a large APO is out of my budget. Following on from our conversation in the Telescopes section it will either be a SkyMax Maksutov 180 or a 10" Newtonian upgrade in a year or so.Regards.Tom
Posted by Andrea Tasselli at 00:18 on 2010 Oct 19
Hi Tom,Refractor unless they are large (over 6") and for achromats long (very very long; for a 6" at least f/15 to f/20 really) are not worth considering for imaging purpose. These filters are , in my humble opinion, just hiding the issue by removing or diminishing some of the offenders. Ditto for b&w whereas you can’t see it but it is there anyway. The only safe way to image using achros is to use a monochromatic imager and RGB composite technique to get rid of CA (but you’d still get chromatic spherical aberration the faster the telescope the worse it is going to be). Reg’sAndrea T.
Posted by Tom Moran at 08:18 on 2010 Oct 18
David.Thanks for that. The fringe killer is certainly on my list. I have the Orion Skyglow. Would I get the same result stacking it with the Fringe Killer? I had discussed my telescope upgrade with Andrea Tiselli and he thought highly of the Maks also. I think it is down to a 10 inch Newtonian or a 180 Skymax Makustov. I enjoyed your web site.Clear skies.Tom
Posted by David Mottershead at 19:34 on 2010 Oct 17
HelloWhen using my 120mm refractor (see here, http://britastro.org/baa/index.php?option=com_kunena&Itemid=100007&func=view&catid=18&id=195#201), and depending on what I am viewing and the magnification I am using, I stack Baader Neodymium and Fringe Killer filters, giving the same results as the Baader Semi APO filter. The advantage of having the two (I already had a Neodymium filter, so simply added the Fringe Killer) is that I can still use them individually, e.g. the Neodymium to reduce light pollution etc, but then gain the benefits of the equivalent of the Semi APO filter when stacked – and the Semi APO is apparently well regarded as a planetary filter when used in achromatic refractors.As for the 150 refractor, that will give more light grasp than the 120, allowing finer detail to be seen, and will allow a higher theoretical magnification, but in reality I’d suggest that the highest magnification that you might use on the 150 will be pretty well the same as that of the 120 – and magnification isn’t what it’s about anyway. The better light grasp on the other hand is always worth while to catch the finer, more subtle detail that a smaller scope can’t resolve. If your main interest and area of observation is lunar and planetary, have you considered a Maksutov? These are, in my opinion, one the best lunar/planetary scopes around.A good image of Jupiter as well, and nothing wrong with black and white.Hope this is of some use.
Posted by Tom Moran at 13:08 on 2010 Oct 17
Hello.I don’t know if this will work, but here is a link to my JUpiter image:http://www.flickr.com/photos/48778860@N06/5089337618/RegardsTom
Posted by Tom Moran at 13:04 on 2010 Oct 17
Callum.Cheers. I think that is the problem. A link to a Flickr site would probably be best. I’ll try and set one up.Tom
Posted by Callum Potter at 12:44 on 2010 Oct 17
Hi Tom,is your image bigger than 800×800 (in either dimension), or 150KB – if so, it won’t be posted. Regards, Callum
Posted by Tom Moran at 14:10 on 2010 Oct 16
Giant filament 16_10_2010. 10.00h UT. I thought the sun had forgotten us here in the NE. Lots of passing cloud meant imaging had to be quick.
Posted by Paul A Brierley at 07:00 on 2010 Oct 13
Thank you Len, Callum.Your link Callum is what I was after, cheers.Thanks again.
Posted by Callum Potter at 22:39 on 2010 Oct 12
Hi Paul,the RA and Dec are on the Deep Sky Section page about the nebula. See:http://britastro.org/baa/index.php?option=com_content&view=article&id=545:gm-1-29&catid=101:observing-reports&Itemid=129Cheers, Callum
Posted by Len Entwisle at 21:42 on 2010 Oct 12
This link may help http://www.fredda-o-ac.se/KPO/pvcep.htm , It has a field picture plus RA & Dec . This may be of interest re associated nebulosity ( 20 year old paper !!) http://articles.adsabs.harvard.edu//full/1991MNRAS.249..131S/0000131.000.html
Posted by Marlyn Smith at 09:46 on 2010 Sep 30
The two images below by Dave Tyler show a flare timed at 1031UT 2010 September 21 and at 1043UT that day a prominence showing loops of magnetism around the flare region.
Posted by Julian Parks at 16:25 on 2010 Sep 28
Creating your own version sounds like the thing to do. Remember it is your own personal Observing Logbook. May I suggest put in there items that mean something to you, but also to others who may read it. The items should be reliable, accurate, relevant, and to the point for your location and the type of observing you plan to do. Good luck and Clear skies.
Posted by Marlyn Smith at 15:18 on 2010 Sep 27
The white light images below are by Dave Tyler showing first AR1109 on 2010 September 25 at 0935 UT and then AR1108 nearing the western limb on the same day at 0937 UTThe third image is a full disk image in H-alpha by Sheri Lynn Karl also on the 25th at 1506 UT
Posted by Marlyn Smith at 09:24 on 2010 Sep 20
3 superb images from Dave Tyler. The first is a wide shot of AR1106 on the disk and AR1108 rounding the eastern limb 2010 September 16 at 1418 UT. The next 2 images were taken 2010 September 18 at 0850 and 0927 respectively showing filaments, a flare and sunspot group 1106 and the last image shows AR1108.
Posted by Marlyn Smith at 17:28 on 2010 Sep 17
Below an animation by Andy Devey of a hedgerow prominence, 32 frames taken over 9 minutes between 1436 and 1516 2010 September 14th
Posted by Rich Smith at 11:22 on 2010 Sep 17
Thanks Julian, i have looked at those things that youve mentioned already, still not quite what i wanted… maybe i should create my own version?
Posted by Marlyn Smith at 07:46 on 2010 Sep 17
Images by Sheri Lynn Karl taken on 2010 September 14th. Whole disk image taken at 1057 UT close up of AR1106 times at 1141 UT. Click on an image to see it enlarged.
Posted by Julian Parks at 17:18 on 2010 Sep 16
Here is a link for a company that sells various types of logbooks at http://www.astrologs.com/ and for observation forms at http://www.saguaroastro.org/content/downloads.htm The Sky-at-Night magazine comes with a CD that has observation forms and sometimes logbook formats. There are also logging and planner software like Deep-Sky Planner at http://knightware.biz/dsp/index.php and AstroPlanner at http://www.ilangainc.com/astroplanner/. The software maybe more than you want though, but they are good and easy to use.
Posted by Tom Moran at 20:00 on 2010 Sep 15
Andrea.Thanks for that. I’ll have to try out a 10inch Orion one of our members has here at Newcastle Upon Tyne Astronomical Society. If so I’ll have to get some step ladders as my observatory pier (concrete in a drainpipe) is designed for a refractor.Regards.Tom
