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wxsatuser

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Everything posted by wxsatuser

  1. 23cms is very quiet here in south central Sussex, takes some tropo or a contest to get stations out. I can just hear the Martlesham beacon near Ipswhich using a Create 21element logperiodic attached to my ICOM 9700. It doesn't beam my way, it beams east and west, you may be able to hear it. When I beam towards it I get the Gatwick radar over loading my receiver.
  2. That is better. The worst area is bottom left, as above crop it out. Unfortunately all Samyangs are not equal, some are better than others.
  3. Some star trailing, focus seems good but in that test I would go with the kit lens at those settings. Not what you want to hear no doubt but the Samyang has the obvious coma. You should be able to shift the chromatic aberration with software and a lens profile. Do this on the RAW file. BTW the filter will shift the focus point as it's another piece of glass in the way. I wouldn't worry about it as long as you get good focus.
  4. The coma is not good if that is f/4. Try the focus without the clip filter and see if it comes to infinity.
  5. It has sagittal astigmatism/coma in the corners, the flying birds, with some chromatic aberration and vignetting. Not unusual for a lens of this type, not massively obvious unless we pixel peep, about as good as it gets at f/2 imo.
  6. For star clusters an unmodded camera is perfectly ok. If you have a real dark sky there a 600D should pick up some nebs on long exposures as well.
  7. My 6Dmk2 does release the shutter with out a lens, all my Canons do.
  8. I would have thought that diagonal pattern is not right. The column not a problem as such.
  9. Going back a bit I had two stacked 55elements on 23cms, very sharp. I hear there are fake Diamonds out there, buy from a reputable dealer to avoid disappointment.
  10. You will not find anything about it apart from it was supposed to be funded with Dogecoin. Musk has talked up Dogecoin a few times so may be this tells some thing, calls himself the Dogefather. On Saturday Night Live Musk called it a hustle, and howled, “to the moon,” a catchphrase used by doge enthusiasts intent on getting the cryptocurrency to one dollar. Make of this what you will, this I found looking around financial sites btw.
  11. High flying birds like geese may reflect light and appear like a satellite. Not saying it was a bird but it may explain a wobbly path and slow or speed up. Never seen a satellite do anything unexpected and have seen the usual flares, blinking and going into eclipse. I have seen large birds at vary heights when imaging and surprising how many fly at night.
  12. Well done that is a keeper.
  13. Have a look at this https://skyandtelescope.org/astronomy-blogs/explore-night-bob-king/random-meteors-arent-random02112015/
  14. It is excepted amongst us radio amateurs that the best time for random meteors is from midnight to about midday. When I did meteorscatter I always tried to get skeds after midnight but you had to be quick to get in before the best slots were taken. I have no idea if the speed matters but we definitely got more meteors in the hours just before and after sunrise.
  15. We did not protest when Mr Brown dropped it to 15% but it did not last of course.
  16. This one of my favourite objects as well and you have done it proud Peter.
  17. I can assure you that us Brits know full well what VAT is and that it is in the price for consumers. If a business deals mainly with businesses then prices will not have VAT. If they deal with both businesses and consumers then the price will include VAT if not both prices should be displayed with equal prominence. At work we deal with mainly businesses, when we quote prices to a business it is assumed there is no VAT added although we always quote the price plus VAT. We do this because some unscrupulous firms try to catch you out by claiming the price you quoted is the lower price without VAT. The arguments I have had with some of these chancers, they are just trying it on or are ignorant of the law.
  18. I have one if your still interested..........£325 including tracked delivery or pickup for £295, I'm near Worthing btw. It is in very good condition and will post some photos if your interested. You can see what I did with it by clicking the link in my sig. Only used it for Ha on an Atik 383.
  19. Here is an image of the tropo signal with a satellite and just left of the tropo signal is a diverging signal, aircraft.
  20. I would say aircraft. I see these as well, often they appear along side the tropo signal that I receive direct off the GRAVES side lobes. Normally they run parallel and then diverge off the main signal.
  21. There are very few zoom lenses that can do better than that. Just like scopes we need to spend an arm and leg to get a good one. What is the zoom lens btw
  22. Modern cameras have on sensor dark current suppression. The 450D does'nt have it.
  23. If your doing short exposures, longer exposures may help, expose so the camera histogram peak is at least 25% from the left.
  24. Cannot help with the filter but it may cause a reflection, may be some one else will comment on that. Re diffraction spikes. As you stop down they become more noticeable. An even number of of blades gives the same amount of spikes, 4 blades 4 spikes. An odd number of blades produces double the amount , 9 blades 18 spikes. You either love or hate spikes, me I don't care, it's something we have to expect if we use camera lenses.
  25. Can I just add, although your sort of correct there are two autofocus systems in Canon cameras. The sensor autofocus only works in Liveview mode or in mirrorless cameras, I believe the whole sensor is used in dual pixel AF. In view finder mode there is a dedicated autofocus chip, I would assume that one wouldn't use Liveview in AP.
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