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geoflewis

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geoflewis last won the day on March 20 2016

geoflewis had the most liked content!

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About geoflewis

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    Proto Star

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    Norfolk
  1. I also use the DSM app. In my opinion it's a pretty reliable, cheap alternative to a dedicated SQM meter working down to about SQM 21.5.
  2. Hello and welcome from South Norfolk
  3. Good luck Alan, I find GCs a welcome source of targets during the light summer nights and very useful for doing some testing. Geof
  4. A superb composition Rodd. I've only ever imaged this close up, but I really like to see it alongside the adjacent dark nebula with rich star field background. Cheers, Geof
  5. Thanks Alan, it's so low down for me that it almost doesn't exist at my location , along with several other summer Messiers. M107 is another cluster that I haven't imaged for a few years, so I may try that one again this year as it's at a much more accessible altitude. Cheers, Geof
  6. Well maybe not quite a fest, but a 4 course meal.... I previously posted my recent M5 image, but I continued capturing more globular clusters during the clear, but Moonlit nights earlier this week, so here are 3 more... M92 - the 'other' Hercules Cluster M12 M28 At first glance globular clusters can all seem somewhat similar, but seen side by side they take on their own character. The seeing for M92 was better than for M12 and M28 and in addition M28 was a very challenging target as it only just about reaches 10 deg altitude from my location which is the limiting altitude for my scope seeing over the observatory wall. All the green data subs that I collected over 2 nights proved unusable, so I resorted to processing the little red and blue data by creating a synthetic green to produce a colour (RGB) image. Nevertheless seeing the cluster against the backdrop of the rich starfield in the direction of the center of our Milky Way galaxy makes for an interesting image and I'm please to add this one to my personal Messier collection. Anyway, I hope that you enjoy seeing these 3 and thanks for looking. Cheers, Geof
  7. Welcome Matt, that MW pic is a great way to introduce yourself. You'll find lots of great advice on here. Cheers, Geof
  8. Thanks Donal, it's good to have some bright RGB targets to image during the summer months, and/or when the Moon is around. I'm having a go at M92 now, then later hope to capture a few more subs on M28, which is down around 10 deg alt, so only available briefly. I got a few last night, with luck I'll get enough to process an RGB image; I won't bother with any Lum for that one. Cheers, Geof
  9. Thanks, I'm pleased that you like it.
  10. With the planets too low this year for successful imaging, permanent astro twilight almost upon us and a bright 1st qtr Moon riding high last night I decided to capture the bright globular cluster M5 whilst experimenting with different PHD2 guide algorithms. I used PPEC for RA guiding and Hysteresis for Dec both for the first time. I had excellent guiding of <0.5" total RMS with both axes reporting ~0.33" over 3.5 hours (excluding dither excurtsions). Here is the resulting image, which came out pretty well considering the bright background sky. LRGB: 30:15:15:15 x 120s The data was captured with the QSI583wsg using SGP through my C14XLT + x0.63 Optec telecompresor lens, with a Lodesar X2 for guiding. Calibration and post processed using Registar and ImagesPlus6.5. Thanks for looking. Geof
  11. I was out imaging until dawn, stopping just after 4am with a bright blue sky, both to capture some targets, but also to do some summer nights testing. The sky never got really dark as the brief true night was lit up by the Moon, then we were well into twilight by the time it set. I was RGB imaging a couple of globular clusters for my Messier list as they are bright targets that can cut through the bright background pretty well. Certainly not much point going afrer any dim targets for the next couple of months, but with Jupiter and Saturn so low this apparition I thought I'd use this summer to grab some of the brighter summer Messiers that I have previously ignored, or have only got poor versions. I was also using the opportunity to experiment with PHD2 algorithms by using PPEC for RA and Hysteresis for Dec, the combination of which gave better guiding performance than my previous Hysteresis for RA and Resist Switch for Dec. My AP1200 is a well behaved mount with very little backlash, so the thinking is that Resist Switch might be a too aggressive DEC algorithm, so I'll continue with the new settings for a while. Here is a screen grab from PHD2 Log Viewer which reports less than 0.5" RMS (excluding the dithers) over a 3.5 hour session on M5, with both RA and Dec in balance at 0.33", showing a nice even scatter graph. This dispalyed graph is just the last half an hour or so, with stats and scatter for the full 3.5 hours; the graph looks pretty much the same the entire 3.5 hours. I've yet to process the M5 data, but hopefully it will turn out ok. Cheers, Geof
  12. True if you want to wait for it's maximum altitude, but it's up to ~25 deg by 2023 and gains about 5 deg altitude per year the following few years, so with an ADC I can work with that.....
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