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Alien 13

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Everything posted by Alien 13

  1. The landing is often the best bit.. Alan
  2. Have I missed something, still waiting for the first stage landing 😋 Alan
  3. I think even a 90mm Mak would give a long 80mm Frac a close call and the Mak is much easier to mount, the other big benefit is no wobbly focusser, you can hang several kilos off the back of a Mak with no ill effects.. Alan
  4. Some lovely bits of kit there.. Alan
  5. My problem is that there is no realy decent 40-60mm scopes on the market with short focal lengths with field flatteners that can handle a correct image 2 in diagonal. Alan
  6. I do like small scopes but there is a case for both, a large scope is never going to give low magnification or wide field views which is what I prefer... give me a 40-50mm objective any day. Alan
  7. I have enjoyed them all, have missed the last few because Leicester City have been playing a lot of matches on a Sunday recently 🙂 Would love to see more tutorials using Afinity Photo especially now that it has dedicated Astro stacking tools etc. Alan
  8. I do and my dog used to do the same,.. Alan
  9. Not sure why this is unless you have the in camera long exposure noise reduction turned on or are using mirror lock up in combination with the intervalometer and adding in the self timer function. Alan
  10. Nothing wrong, you have to allow time between shots for the camera to write to the SD card..I normally leave a 10 second gap. An ultra fast SD card might reduce this though. Alan
  11. Very nice, had the Artcise and Sirui tripods in my basket for a week, eventually chose the Sirui because it would get more use and Amazon were offering free 4 months credit too. I did buy an Artcise MB 36 ball head to go with it though.. Alan
  12. I have the 254 version of the SIRUI (same design and construction) and its superb for my needs, weight around 1 Kg and can hold 12Kg with ease.. Have a look at the Artcise tripod, probably the best on the planet for the money here. Alan
  13. Great stuff, when I was a teenager the thought of a electric helicopter/drone being able to lift off while being self powered was the stuff of Science Fiction. As to space exploration in general each generation hits a brick wall with the limits of the current technology and has to wait for another breakthrough before planning new types of missions. We are a bit stuck with rocket propulsion at the moment but the payloads can be incredibly small in the future. Alan
  14. Ooh, just noticed the range includes microscope bags, nice.. Alan
  15. Hi Steve, Its a difficult choice with so many lenses out there but for starters the 50mm f/1.8 STM is good for the price, after that you get into serous money with the likes of the Samyang 14mm/28mm/135mm which are very good for AP. You can also get good results with the standard kit lenses or push the boat out a bit for the 70-200mm f/4 L lens which is reasonably priced second hand from WEX or MPB photographic. Alan
  16. I think tethering uses the basic video out rather than the processed image you see on the camera screen that has other options too like exposure simulation. I know I can easily see mag 6 stars and below on the live view screen. Alan
  17. In my experience the on camera screen will give far better results than any tethering software for focus using x10 zoom etc. Alan
  18. As far as mirrors go the Questar 90mm scopes leave Tak in the dust for price per sguare mm. Alan
  19. Its odd but looking at the realy dim stars some looked to have focus nailed and some off... Alan
  20. Didn't think small Taks were any good for imaging without replacing the focusser and using a tiny sensor 😀 Alan
  21. It depends somewhat on the type of scope too, if its a frac then changing the f/ratio by increasing aperture would be disastrous without also increasing focal length too and by more than double, you might be able to do this with a mirror based scope though. Alan
  22. Zeus looks like one of these not that expensive either in the grand scheme of things.. Alan
  23. Makes you wonder when it goes Supernova if the energy released will be directional or offset. Alan
  24. I quite like "crop factor" provided the calculations are done correctly, works for depth of field too. Lets say you have a full frame Canon camera with a f/4 50mm lens, you can get the equivalent image from a Canon crop body including identical depth of field and noise by applying the calculations as follows. 50mm/1.6 = 31.25mm but you also have to apply to the f/ratio so (f/4)/1.6 = f/2.5 So a 32 mm f/2.5 lens would give near identical results on a crop body to the 50mm f/4 on a full frame. Alan
  25. Assuming you are using the same sensor with these scopes then aperture will win for light collection but will not necessarily give the best results if one of the combinations is a mismatch regarding the pixel size etc. In the Camera world f/ratio is useful for obtaining correct exposures but there is no way a Camera phone lens at f/4 is the same as a full frame f/4. Perhaps astro kit should use the "crop factor" calculations in there specs 😋 Alan
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