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ejwwest

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Everything posted by ejwwest

  1. Took this this morning: Sun and Sunspots by ejwwest, on Flickr Compared this taken on Sunday, the large sunpot group (AR2036) in the middle has formed since (over thepast 24 hours according to spaceweather.com): Sun and sunspots by ejwwest, on Flickr
  2. best site for timings of transits is www.calsky.org Be aware though that solar and lunar transits have a very narrow path on the ground (a few kilometres wide at best) so you have to be on the path to see them. If you enter your location into Calsky it'll tell you the path of the centreline so you can see where nearby ones are. In my experience there are usually a couple of solar transits a year visible from my house, and many more nearby to travel to (usual caveats on weather etc).
  3. Excellent. Rarer than Solar transits and also harder to get the exposure right!
  4. That really is good - much more detail on the solar panels than with my DSLR.
  5. No, I have it pointed to a fixed point it's predicted to go through (usually the maximum altitude). I haven't yet tried either manually following the ISS or computer controlling it.
  6. My plan to do a bracketed exposure failed, but got this one shot at the tried and tested exposure! Another ISS Closeup by ejwwest, on Flickr
  7. http://www.heavens-above.com/ is good for general ISS appearances. If you want more precise details or want Solar/Lunar transits then use http://www.calsky.com
  8. I used my Canon 70D. Its 7fps and roughly 30'x20' field of view on the EdgeHD 925 so gives a good chance that there'll be 3 or 4 usable shots each pass. I also try to get the ISS tracking diagonally also to maximise the chance of usable shots.
  9. What I do to to get a focus is to use a Bhatinov mask and focus on a star first. On exposure the main problem is the dynamic range: parts are very bright and other parts very faint. With my Canon 40D I found ISO 1600 and 1/1000s seemed to get good results but with my 70D go for about 1/2000s and 2000ISO (the scope is f/10). The centre is still overexposed but get reasonable exposure on the solar panels and peripheral parts of the station. If I try tonight's pass I may try bracketing exposures at (say) 1/2000s, 1/3000s and 1/4000s (I probably won't get more than 3 shots in the pass) and see which works best. The fact is it is 250 miles away at best, moving fast and there's lots of turbulent air in between so there's a limit to what can be obtained. My experience is that a high ISO is more tolerable to obtain a short exposure. However, for something to aspire to, Thierry Legault has some stunning images (eg: http://legault.perso.sfr.fr/STS-133.html ). His equipment is both better AND he has set it up perfectly (eg I think the collimation of my EdgeHD 925 is probably what I need to fix next).
  10. A closeup at prime focus of the EdgeHD 925: International Space Station by ejwwest, on Flickr A slightly better one with 4 shots stacked: ISS by ejwwest, on Flickr And a long exposure of its tracking across the sky (three exposures of 1 minute each): Pass of the International Space Station by ejwwest, on Flickr
  11. This was three shots taken with my Canon 70D at prime focus of the EdgeHD 925 merged together: Moon - 12 days old by ejwwest, on Flickr
  12. Here's some examples from the 2007 (https://www.flickr.com/photos/ejwwest/sets/72157594571245814/ ) and 2008 (very cloudy: ) that I took using the Canon 100-400mm lens and 2x extender (so 800mm f/11). I typically took 10-20s shots mid eclipse and had it piggy back mounted on a scope tracking Lunar (though in 2007 I discovered I hadn't locked the drive so many shots came out blurred).I'd try different exposures and would suggest shooting in RAW so you can adjust the white balance later if necessary. For lunar eclipses you should have, weather permitting, plenty of time to try out different settings - unlike a solar eclipse during totality. Oh, I'd take off all UV filters (definitely do that in a solar eclipse should you be planning ahead for 2017) so you don't find reflections from bright areas on the final images.
  13. A lot better than my first attempt on the last apparition of Mars in 2012.
  14. I have considered trying my DFK21AU618 but the sensor is very small and the accuracy of the scope alignment too uncertain (that's ok when you have to then do fine adjustment on a bright object). The DSLR has a large enough field of view that you can count on a couple of shots having the ISS in when it's overhead (the 70D has 7 fps). I have also found shortening the exposure and upping the ISO a better tradeoff - the image won't be sharp anyway, so increasing sensor noise is better than motion blur. I know some have successfully managed with a video camera and then follow the ISS as it moves, manually or by computer control, and then stacked the video stream. That requires a lot of setup and patience! I may try the video function of the 70D and see how many frames have the ISS with the scope fixed.
  15. I have a Bhatinov mask so try to get a good focus on a star before hand and then point the scope to a position on the predicted path by Calsky. With an exposure of 1/2000s the motion blur is more or less gone. There's more structure visible on this shot than most of my previous attempts.
  16. First attempt at Mars this apparition: Mars by ejwwest, on Flickr
  17. Taken at prime focus of EdgeHD 925 with Canon 70D: International Space Station by ejwwest, on Flickr
  18. The Thousand Oaks has a 77mm thread so easily screws onto the lens and is compact and robust. It's quick to setup and very portable which is its attractiveness (I got it for the 2008 eclipse in China). I made some filters for my 50mm and 80mm binoculars from Baader film but they are quite flimsy and not as robust or convenient to use. Should I want some high quality sun shots, I'd take the time to setup my EdgeHD 925 which does have a Baader (or similar) filter. I have some spare Baader film I think so I could try it with the Canon zoom lens.
  19. Taken with Canon 70D and 800mm lens with Thousand Oaks filter. Sun and sunspots by ejwwest, on Flickr
  20. Normally the telextender takes lenses like the 100-400mm beyond f5.6 (to f/11 at 400mm) which, for some reason, means the normal autofocus doesn't work. Manual focus has the problem of keeping the image steady enough at this high a magnification whilst adjusting the focus ring. However, I successfully managed to get EOS Utility to adjust focus on the 70D with the extender attached. I'll just have to wait for a sunny day to try this with the sun.
  21. I think the problem is with the 2x extender - with my 40D I couldn't get the Canon Utilities to fine adjust the focus with the extender on the 100-400mm lens, but could without it. The 70D comes with a new technology "Dual Pixel CMOS AF" whereby in LIveview there's contrast detection between adjacent pixels which I think may allow it to focus with the extender on. As I was trying to manually focus this morning the camera started (slowly) focusing down to minimum then back to infinity and seemed to get a reasonable (but clearly not sharp) focus. I'll try the utilities to see if I can improve it next time. I did get a manual focus but at a longer exposure than desirable which I processed with PSE 12:
  22. It's comparable with best attempts at manual focus through Liveview given it's very challenging in bright sunlight to adjust the focusing ring and keep the image steady enough to focus. I'm not sure the EOS utilities will work as I think the reason the Liveview auto focus works on the 70D is because of the builtin new technology. However, will give it a try next time I get the chance.
  23. Taken with my 100-400mm zoom lens and 2x extender and Thousand Oaks Filter. Is it me or is the Canon 70D able to achieve autofocus at f/11 with the 2x extender on via Liveview? The camera definitely did focus automatically, albeit very slowly. Sun with Sunspots by ejwwest, on Flickr
  24. Taken at the start of the session last night whilst Red Spot still just visible: Jupiter with Red Spot and Shadow of Ganymede by ejwwest, on Flickr
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