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About JohnSadlerAstro

  • Rank
    Proto Star
  • Birthday 29/07/2001

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  • Gender
  • Interests
    Astronomy, Aircraft, Aviation Gaming, Physics, Technology, RC Aviation, and Model Making
  • Location
    Chippenham, Wiltshire
  1. I use the 130P-DS and coma is horrific when using my 1000d. It's just part of having a short-f ratio scope.
  2. Hi, Using the coma corrector may result in a small loss of backfocus; but I have never experienced any issue when using one. I use the Baader MPCC, I would definitely recommend it. It's not too expensive, but it does the job well! John
  3. M81 & 82

    I never imagined that the background would be so improved when i started dithering. Before, subtracting darks (And a 1000d is a NOISY camera!!!) would result in interesting black streaks across the background, giving the sky the effect of wedding-invite paper. Now, I can remove the sky brightness sooo easily. I am planning to get more data over the next few weeks, the galaxies never really set, so there should be plenty of opportunities!
  4. m78

    That looks like one awkward target! I'm not sure if there's really much more than what you have already picked up, though I'm guessing that a bit more data will slightly improve the noise. What exposure length/iso are you running? John
  5. M81 & 82

    Hi, I feel rather ashamed posting in this area, but I need to challenge myself to improve, so here goes. Bode's Nebula and the Cigar Galaxy taken on Thursday night. * 1h 35m of 240 & 300 sec exposures (RAW), ISO 800 * Cannon EOS 1000d * EQ5 with 130P-DS, guided with PHD2 & Captured with APT * 50mm Finder/Guider and ZWO ASI webcam as guidecam * Baader CC & Skywatcher LP filter (very cheap ) * Stacked in DSS, Processed in GIMP 16-bit version I had some trouble getting everything working on the software/control/guiding side, as this was my first imaging session using a new laptop. I was also controlling everything from indoors for the first time. Unfortunately, I messed up a lot of the guiding, but somehow the equipment managed to overcome my mistakes! This was made from the best subs out of around 2h 30m total exposures, I believe there was a slight wind which blurred some of the subs. Processing has been a bit easier than usual, as I was dithering (for the 1st time ever!) which massively improved the background. However, its very difficult to get the arms of Bode's Nebula without washing out the detail in the Cigar, but I think I've found a middle ground. I have had difficulty with "grimy" colour in many of my images, with strange colour balance or a lack of colour contrast which is almost impossible to correct. Does anybody know the best ISO setting for the 1000d? I'm currently running 800; but I'm not sure if that's the best contrast setting.
  6. Strange PHD graph

    I used to. However it was quite a veteran and also didn't enjoy the cold....get the picture? I'm thinking, if indeed the USB cables *are* causing a slower transfer rate, surely it will only have the effect that longer exposure lengths would have? I usually run 2 sec expos, but i could easily increase that and I surely the subs wont suffer and streaking or blurring, with the short focal length I'm using. Something i notice on all my images is that the colour always seems a bit "grimy" compared to the snow-white galaxies and black background the ppl over in Imaging-Deep Sky are getting. Is this just the result of using a budget camera and simple Skywatcher LP filter? John
  7. Strange PHD graph

    Well, seeing as I did so much wrong, its rather a testimony to the Grandfather of All CMOS sensors (my 1000d) and my EQ5 that the image came out so well!!! John
  8. Strange PHD graph

    So am i right in understanding that PHD "thought" that each pixel was covering more sky than it actually was, therefore giving horrifying accuracy results when they were converted to arc seconds?
  9. Strange PHD graph

  10. Strange PHD graph

    AH!! That must be part of the trouble! I thought I remembered it being 55mm focal length; so therefore all the commands PHD was giving were waaay to harsh.
  11. Strange PHD graph

    Is that an extremely lengthy process? I remember trying to drift align with a crosshair eyepiece back when i had an EQ2 with no Polar Scope and it was a nightmare.
  12. Strange PHD graph

    Hi, I was imaging M81 and 82 last night, which were almost directly overhead. The USB cables I was using were about 20m long, (to go through our letter-box and into our dining room, I don't like standing in the cold at 3 am ). I re-ran the calibration process with the scope pointing at around +7 dec, and it seemed to work ok, but there were still very strange RA behaviours, with the guiding graph looking like a series of RA hills ending in vertical cliff-edges. After a while, though, the guiding seemed to settle down a bit; about 60% of my subs were useable (I think there was a bit of a breeze). I was running an EQ5 with dual-axis drives with 130 PDS. I aligned using the polar scope (I was trying using SharpCap to align, but then realized I needed to buy a license in order to unlock the last step of the PA feature--I may do that at some point). My guidescope is a standard 50mm finer, its quite small but as I'm using a DSLR and a short focal length scope there doesn't *seem* to be an issue with that. EDIT-- Is the SharpCap PA tool worth spending the £10 for pro license with the kit ive got? Is this what you were meaning? Also, how do I find the Guiding Log?
  13. Strange PHD graph

    The Best I can get. I'm hoping this will be enough to remove tooo much blurring.
  14. Strange PHD graph

    Can anyone make any sense of this? I have just started using a set of USB extension cables, I'm hoping they aren't causing issues. It seems to be some error in the calibration data, I'm trying a re-calib, hopefully it will work soon. John
  15. ZWO Camera Won't Connect With PHD2

    Hi, I restarted my laptop and it seems to be working now!