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geoflewis

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Everything posted by geoflewis

  1. Hi Neil, Rather than me trying to post a workflow, please try the workflow in the below link from Farnham Astro, which is the method I use for adding comets one by one. http://www.farnham-as.co.uk/2013/11/adding-comets-to-stellarium/ For 46P, use the online search tab and enter 46P/Wirtanen into the search bar. The search should return the comet, so then tick the checkbox and click the Add objects button. I'm not sure if there is a way to add a full current list, but if there is then I'd also like to know. Hope this helps. Good luck, Geof
  2. Tonight is my first clear sky in ages, but 30-40mph wind gusts, so no chance imaging - well I tried but couldn't even get a focus V curve due to telescope shake, so I gave up on that and decided to look for comet 46P with my 15x70 binos instead. First I added it to Stellarium to work out where it is, then star hopped from 2.5 mag Menkar ( α Cetus) down to 3.8 mag Azha ( η Eridanus) and back up to the line of 3 5th/6th mag stars ρ (Rho) 1,2 & 3 Eridanus and there is the big fuzz ball of comet 46P/Wirtanen. Despite being low down in the murk and locating Azha was very difficult naked eye, once I got that finding the 3 stars ρ (Rho) 1,2 & 3 Eridanus and the comet was very easy. As a very rough guide to locate Azha, I imagined a straightish line from M45 (Pleiades) through Menkar and about half as far again towars the horizon. Whilst not particularly bright Azha was the only naked eye star that I could see in that region, so once I'd found that I was good to go with the binos. Good luck anyone else trying to finding it by star hoping tonight (7/12) - I hope the above helps. Cheers, Geof
  3. ....one is more than enough, just glad to help you resolve the problem. Cheers, Geof
  4. Hi cloudymoon, It sounds to me as if you have long exposure noise reduction set to ON in the camera, which means that the camera shoots a matching dark to whatever image exposure you shoot and applies that before downloading the image. I'm not familiar with the 1100D, but I used to have a 600D and turned that feature off. You mentioned shooting seprate darks and flats, which is what i'd recommend, as you don't want to waste dark sky time with the camera shooting and applying darks with every exposure. Hope this helps, Geof
  5. I spoke to Ian at AA last week and they were certainly still trading then . I live about 40 min drive from their shop, so I do pop in from time to time as it's generally easier to get a quick answer that way. It's a small shop usually with just Ian working there and from my experience their phone never stops ringing, so I can well understand the difficulty getting through - I have waited well over half an hour in the shop whilst Ian was on the phone to a single caller (possibly another astro shop checking on products). I think the advice to purchase from one of the other astro shops that sell their gear is good, but that is not to say that you won't get a reply from AA direct, as Ian has always got back to me, just sometimes it takes a while. Good luck, Geof
  6. In my experience M31 is naked eye (averted vision) even from fairly light polluted skies. 25+ years ago I live at Staines, Mx (now Bortle 6 - I don't know what it was, as no Bortle scale back then) and later at Frimley, Surrey (Bortle 5 - SQM~19) and had no difficulty finding it with AV at both locations in a moonless sky. BTW M13 and the double cluster were also fairly easy targets for me at both locations. I now live in South Norfolk (Bortle 4/3 - SQM range 20.8-21.5 depending on seeing) and all 3 are easy in direct vision and on nights of excellent seeing I have also glimpsed M33 with AV, making that the furthest naked eye object that I have seen, beating M31 by a few hundred lys. Binocular and telescope views of M31 (and of course everything else) are a vastly improved experience from Norfolk than anything I experienced from ~50 years living in Surrey. Dark skies rule.... Cheers, Geof
  7. Thanks Sean, If you hadn't prompted me I would have missed it again this year. You were right about the C14 image scale working pretty well with this target, even with the Optec telecompressor. If the data had been better, I'd probably have cropped it for just the Quintet as well, but it looks really crap close up.... Cheers, Geof
  8. Stuart, I have no ability to critique your wonderful image. I love the side by side of your 'pillars' with hubble, what's not to like... Cheers, Geof
  9. I was prompted to have a try at this target by a comment from Sean (@Craney) in my recent NGC891 image thread.... The Quintet has been on my bucket list a few years, but being a late summer/early autumn target I never seem to get around to it until it's getting too late from my location, which is pretty much what happened again this year. I wanted to capture the data before the waxing Moon flooded the sky, plus with poor weather forecasts of thickening haze/mist/fog I got going very early each evening, starting the capture sequences even before the end of astro twilight. The weather forecasts were disappointingly accurate, added to which on a couple of nights I had strong winds gusting in excess of 30mph, so lots of subs were discarded immeditaely on capture; at least my decision to shoot 5 min subs rather than my usual 10mins worked in my favour, though not much else did....!! Here's what I managed to extract from nearly 8 hours of decidely dodgy data.... I really bullied the data and the RGB stack had some nasty vertical red & green banding, possibly due to passing cloud, which I did my best to photoshop out, so this isn't going to win any prizes, but maybe next year I can do better.... Thanks for looking. Geof
  10. That's a very nice planetary Luke, which I don't think I've seen previously; I shall add it to my list of targets for the C14
  11. I’ll start by saying that I’m not a big visual observer, but I do dabble and I always take a look at Jupiter, Saturn and Mars when they are around. I have classic C14, so a 14” aperture (with central obstruction) and native focal length of nearly 4m. My normal viewing magnification range for the planets is around x200-x325. My favourite is with a 12mm TV Nagler (3905/12=x325), but I often use a 25mm Meade with x2 Powermate (3905x2/25=x312). On nights of poor seeing I use my ES68/40mm with the x2 Powermate (3905x2/40=x195). If seeing is exceptional then I have used the 12mm with the x2PM for a magnification around x650, but that is extremely rare and only worked one night on Jupiter this past year and even then it was questionable whether I got anything more than viewing at x325. I do get away with x650 on the Moon, when the seeing is good and the Moon is riding high; I have even got up to x1000 with a 4mm TV (just because I could), but really that was not a great combo. When viewing DSOs I never get above x325 and most often have the best visual experience at around x200. As others have commented a smaller sharper image is almost always better than a larger blurred image. Also be aware that Jupiter and Saturn will remain very low, i.e., close to the horizon, for the next few years, so in addition to the resulting poor seeing, they will also suffer from atmospheric dispersion which appears even worse at high magnifications, unless you introduce an atmospheric dispersion corrector (ADC) into your optical train. Good luck, Geof
  12. Hi Sean, Yes that target has been on my bucket list for quite a while, but I never seem to get around to it, so thanks for the gentle prompt. Unfortunately it's already transiting by the time I'll get on it now, so I'll need 2 or 3 clear nights to get enough data and once again I've probably missed a trick not attempting it about a month earlier. I hung in trying to image Mars longer than I oroiginally planned this year (with no real benefit), plus we had family visiting from USA for most of Oct, so AP took a low priority last month. Cheers, Geof
  13. Thank you Ruud, Sunshine and Craney, I'm glad that you like it. It's fun imaging at this focal length, but I'm never too sure how the end result will turn out. It can also be problematic guiding through the camera's OAG as there have been several times that SGP/PHD2 couldn't automatically find a suitable guide star in the pick off prism due to the small FOV. For this target there was a choice of 3, almost like Christmas . I also resist performing a meridian flip as that too can result in no guide star after the flip with targets in a more baren region of sky. Fortunately with this mount I can usually image a couple of hours or more past the meridian (CW up) with no issues, so if I start out early with higher altitude targets, i.e. those that transit within, say, 30 degrees of the zenith, then I can stay on target for up to 7 hours without flipping, which makes data capture easier. Geof
  14. Thanks and yes, in truth it's a crazy FL for DSO, but I like the up close and personal results . The C14 native is 3900mm (F11), which the Optec telecompressor reduces to around F7, so still ~2500mm. Fortunately the AP1200 barely knows that it has the C14 atop and guides very well using PHD2. Last night's session averaged around 0.5 arcseconds RMS each axis, with extended periods down below 0.4 arcsecs. I just wish the sky had been more pristine, transparancy was poor.
  15. Thanks Donal. I was down your way recently, popped in to see PCB. Geof
  16. I first shot this target excatly 1 year ago (5Nov2017) with an almost full Moon in the sky. Last night I had another go with no Moon, but very hazy poor transparancy conditions, so still far from ideal. C14+Optec FF/FR; QSI583wsg-5 L=18x10mins; RGB 9x10mins each for a total integration of approx 7.5 hours. All frames binned 2x2. Each channel calibrated and stacked in ImagesPlus. Stacked channels star aligned and cropped in Registar. Post processing with ImagesPlus and PS(CS2). I'm finding Registar does a great job aligning the stacked channel images, so many thanks to all those that persuaded me to buy it, in particular Carole Pope (@carastro) who also provided me with some excellent tuition at Kelling Heath back in September. Thanks for looking, Geof
  17. A lovely report of another excellent session Neil. Cheers, Geof
  18. Superb image Dave. Excellent star colours and the cluster really sparkles.
  19. Well that was a good nights work Bryan. I particularly like the M45, but then I'm a sucker for (RGB) colour and that bright red star top left just sets the whole picture off for me....
  20. Very nice going Stu for just 30 minutes of data
  21. I agree, it's not only smoother, but deeper nebulosity and the stars are more crisp.
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