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About almcl

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    Proto Star

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    Telford, Shropshire
  1. Hope Maksutov-Newtonians are allowed in? Here's another WIP, 60 minutes from the only clear night we've had in the last fortnight (haven't done anything about the amp glow, noise or bright star reflections yet):
  2. No apology needed, I was trying to clarify and, yes, absolutely, a test image with and without filters should help clear things up.
  3. Sorry if it wasn't clear, I was referring to the OP's question, not your response. His issue may or may not be caused by the filter. Mine isn't. It might be him worth checking.
  4. Don't be too quick to blame the filters. I get a similar effect on bright stars with no filter in the train. Beginning to think it may be an artefact of the DSLR matrix/Baader Filter &c (single cropped sub from 1st light with my SW190MN):
  5. Depends what you are planning on doing with the scope. If you are visual only then there's no need for EQDIR and PHD2 and the Synscan handset is all you need. A rough polar alignment should be enough to keep objects in the eyepice field of view. If you are planning on imaging then, depending on what scale, the mounts tracking accuracy probably won't be accurate enough. I started with an unguided EQ5 and did get some usable images, but moved on to guiding.
  6. Another thing that occurred after I typed the above is that the current guidance from the PHD2 developers is to get the guide star as sharply in focus as possible. The old advice about 'soft stars' is no longer current, although it still seems to be repeated...
  7. +1 for Laurin Dave's suggestion to increase the star mass detection tolerance. 80 or 90% may not be too much. Also might be worth increasing the search region size, so that if a momentary loss of guide star occurs, it gets found again.
  8. If you are using one of the later versions of PHD2, the present developers (Andy Galasso, Bruce Waddington &c) recommend (sometimes on an almost daily basis on the Open PHD guiding forum) getting the guide camera focus as sharp as possible: link 1 link 2 While the centroid computation can cope with some pretty hefty distortion (fortunately for those of us using OAGs), they state that the best results come from sharp guide stars. They suggest using the HFD figure as a guide and adjusting guide scope focus to minimise this. For me that figure is seldom stable enough to judge whether an adjustment has improved matters so some sort of mask can be very helpful. To get a small 3d print, I have used 3d Hubs in the past and they were pretty reasonable and fairly quick. I think it was a case of up load the file, choose the material and some other things and they quoted there and then.
  9. Thank you for both of those, Han. I'll have another look.
  10. May not help, but if your LED street lights are like ours... I was mildly surprised/absolutely flabbergasted to see the council lighting contractor fitting a shade to the light outside yesterday. It hasn't quite worked, unfortunately, as the shade needs to be about an inch closer to the lamp post, but considering we didn't ask for it, well surprised. Might be worth asking if your council could do something similar
  11. It's hard to be sure about focus as you have star trailing along the RA direction (bottom left towards top right or approximately the line from Sadir to Vega) and the star shapes are a little strange: I've never used a lens with that wide an angle but you might be able to make a suitable Bahtinov mask and use that to check the focus? The colour (enhanced red from the extra IR) is not unusual - post processing can usually deal with this.
  12. A couple of thoughts which may not be relevant, but have you tried solving the image on astrometry.net to see if the resolution &c agrees with your figures? Second are you just using PlateSolve 2? I have found this to be very unreliable. Especially if the target is any distance off. Allskyplatesolver (ASPS), while slower, has a much better chance of succeeding with 'distant' targets, at least in my back garden. If you are using ASPS, have you downloaded the relevant index files for your new resolution and tried going through the troubleshooting routine?
  13. Wonderful data again! But found this really hard to process, particularly without losing some of the Oiii data. Processed in StarTools 1.7.421 alpha standard work flow: --- Compose > Auto Develop > Crop > Wipe > Auto Develop > Contrast > HDR > Wavelet Sharpen > SNR-aware Wavelet Sharpening > Deconvolution > Shrink > Life > Color ----Parameter [Matrix] set to [SHO 40SII+60Ha,70Ha+30OIII,100OIII] > Wavelet De-Noise
  14. Here's a website that predicts seeing. https://www.meteoblue.com/en/weather/outdoorsports/seeing/38.043N-77.350E It looks as though you have a strong jet stream over Virginia at the moment and that often results in poor seeing. Ironically good transparency (clear skies) is often combined with poor stability (roiling air) whilst poor transparency may be accompanied by more stable air. Frustrating isn't it? When you get a rare night that is both stable and transparent, make the most of it, in UK at least, they can be quite rare!
  15. Fortunately a very prominent dust bunny as well as horrific amp glow showed the rotation required (anti-clockwise). Autorotation is turned off in the camera, suspicion now falls on APT which has been randomly flipping images for a little while in its on-screen display.
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