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Darth Takahashi

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Everything posted by Darth Takahashi

  1. Wow, that's a great image but 32 hours... where do you get 32 hours of clears skies? I don't know if I'm more jealous of the image or the fact that you have 32 hours of clear skies ;-) Anyway its an amazing result that will take me years to even try to equal... Neil.
  2. I have a question and a proposal? According to optical theory if I use two telescopes to image the same object and separate them, well lets say by 5m, then I have effectively created a telescope with the same resolution as a 5m telescope, correct. So if I image the moon from Holland with my Mewlon M250 and one of you guys does the same thing in the UK with a comparable C11, and we then send the data via the internet to each other, will we have created a superscope with a mirror the size of the baseline between the locations? Of course, I realise that there are many issues to over come; 1. Matching the focal lengths of the telescopes 2. The local seeing condition at each of the locations 3. Matching the camera's and maximizing their raw resolution 4. Synchronizing time 4. Image processing! To some extent making avi's and rejecting bad frames as already overcomes a lot of the local seeing conditions. Also we could stick to one frequency, Infrared etc... Using filters from the same manufacturer for consistency etc... The network could be extended to include more telescopes to gather more data from difference viewing location and so different viewing angles. Times and target could be delivered to the this SuperScope network using the forum. We only need a cental location for uploading large volumes of data. Namely the raw avi files. I beleive that it would be best to centralise the image processing since I might reject frames that are usuful in the final image. Unless a standard set of parameters could be agreed for rejecting frames? Let me have your comments, what are the flaws if any with the above? Neil.
  3. Great images with lots of resolution, wish I had such seeing conditions! Neil.
  4. Gents, Thanks for the tip, I'll give iMerge ago tonight and will post the results. Once again, Thanks Neil
  5. Very nice image indeed, you've got to give me some pointers on blending as I'm struggling with this at the moment... You can find my poor mosaic attempt also online here. Neil
  6. Thanks for the great comments. Trevor, I know exactly what you mean... Its funny how everything looks great in the eyepiece but as soon as you put the camera in... all hell breaks loose! I keep dreaming of imaging at F22 or F40 like some of the guy's on this forum but its still a dream.
  7. Any helpful hints would be appreciated? I'm struggling to blend these images into one seamless picture. Current effort using Photoshop and layers & levels etc... There's a nice picture lurking in there somewhere... I'm not sure that I have the patience foe these mosaic's. Or maybe I have just underestimated the effort that's required:rolleyes: Neil
  8. Went out last night with the intention of doing some high resolution lunar imaging but in the end as usual the weather wouldn't co-operate with me. Seeing was average along with the transparency The image below is a combination of three frames taken as follows; 1. Telescope Mewlon M250 with Reducer 2. Camera 450D at prime focus 3. Exposure 1/350 @ ISO200 I also took some higher resolution images with my HX916 and will post them shortly. Neil.
  9. Sorry about posting twice, I don't know how that happened, maybe because I had to log back in to post? Takahashi states 15kg for imaging and 18kg max. for the EM200USD3. I have pushed it to just under 19/20kg and still managed to imaged with it. The problem was that the M250 = 15kg + Sky90II 3kg + Tube rings 3kg + BT Technologies mounting plate 2kg etc... In the end when I worked it all out excluding camera's, I had around 23kg load and at 3000mm native focal length for the M250 was just too much. But it did look good. Even my wife commented on it:eek: Still not sure that that's a good thing! Neil.
  10. Well I had a reasonable night on Monday this week and completely wasted it. Still, even the negative experiences are lessons to learn just not to be repeated. Whilst in Japan a couple of months back I pickup a nice short tube sky90II. The reason that I'm telling you this is so the next part make sense! For some strange reason I decided that my EM200 USD3 could just about manage my M250 + Sky90II and mounting material. It looked fantastic and I was just about able to reasonably balance everything with 20kg of weight all hanging on the end of the balance bar? There was a mismatch but I decided that it was small enough to press ahead. After some web cam imaging on the moon with vlounge and a SPC900 I had a brain wave - more like a brain fart! I decided to do some wide field imaging with the Sky90II, all guided by the M250. Many of you are probably already laughing. 1. Guiding by Mewlon M250 and Atik 16C at 0.51 arcseconds / pixel 2. Imaging by Sky90II and 450D at 2.14 arcseconds / pixel This was a disaster but not immediately! The EM200USD3 struggled on manfully for about 5 mins before giving up and lossing the guide star. So what did I do? I adjusted the setting in PHD and tried again:D. Guess what happened, it still lost the guide star... Lessons learnt 1. An M250 + Sky90II are too much load for the EM200USD3, even though it looks good! 2. Guiding at 3000mm in typical Northen European weather conditions is impossible and a waste of time. The seeing is never good enough. Even if I'd had a bigger mount the seeing is the limiting factor! 3. Never use vlounge from Phillips for capture as it uses mov compressed format to record the video stream. 4. The one bonus from the night is that the computer control software from Canon for the 450D worked perfectly. The only other plus point is that I have found the practical limited of my equipment. Other limits that I have suspected for a long time (Seeing) have now been confirmed. Neil.
  11. Hi Mark, You should definitely download stellarium if you haven't already, it great even on cloudy nights;-) Neil.
  12. I haven't gotten into this asteroid tracking business just yet. It looks to be very challenging. Well done and thanks for the big yellow arrow because I nearly missed it. Neil.
  13. Nice animation and image. I've almost forgotten what the star look like! Neil.
  14. Sorry for taking so long to reply, I am actual home in the UK at the moment because my fathers sick and in hospital. Anyway, back to the astronomy. I think one of the difficulties is in not believing that shorter exposure can capture the same detail as longer one's. The trick is to remember that the photon's are arriving randomly. Therefore, the shorter exposures can and do capture the same amount of detail as a single longer exposure. The only real difference in signal terms is the additional readout noise from each of the shorter subs. Think about collecting rain in a bucket, you will collect the same amount of rain in the same time whether you leave the bucket for 30 mins or 6 x 5 mins. The difference is due to surface tension emptying 6 buckets mean each time you will lose some of your rain water and this can be equated to readout noise. The other big benefit that I can see is with the darks. Darks should be as long as your lights and I hated capping the scope for 10 or 20 mins to capture a dart under the same conditions and time as the lights. Shorter darks means that I might doing them along with my lights as I go instead of when I'm ending an imaging session. However, depending on the camera and the noise you might also decide to skip them completely. For me the article can be summed up as follows; Unless you can cool the imaging chip and gain better control of the build up of thermal noise, shorter is always better. On balance after reading this article and listening to the opinions of others, I'm definitely going for shorter subs and not longer ones in the future. And as George shows above, pictures worth 1000 words. Neil.
  15. Its definitely a reflections of some kind and just a guessing :scratch: it is possibly between the CLS Filter and the MPCC? Once one have it stripped down I'm sure you will find the issue, lets hope your relationship with her in doors can survive the trauma? Neil.
  16. Yes, I agree, I'm now of the opinion that when light pollution allows I will only push for 6 min exposures max. Lots and lot of them of course, the question that's still open in my mind is whether or not to continue with DARKS, are they needed with exposures in the 3 to 6 min range at ISO400? For safety I'll still do them but may be in he future I'll try stacking an image with and without them to see what the difference is? Neil.
  17. Today lots of people are using a DSLR to image the sky instead of a dedicated cooled CCD. I believe the reason is simple; if most of us came home to our wife's and told them that we had just dropped 4 to 10K on a camera that can only be used on clear moonless nights and can't take pictures of the family, well, i think you know where I'm going . Canon currently offers many camera that are capable performers where imaging the heavens is concerned, however, once you have your camera and start taking images, determining the optimum settings can be difficult. I too here was apparently heading down the wrong path, striving for longer and longer single exposures. Lots of people here in this community advocate lots of shorter exposures but with no real clear reason why, now I believe that I might of found the proof that shorter is better; I'm uploading a pdf by Craig Shark who goes to great pains of make a fair comparison . In the article it becomes clear why shorter is better where DSLR's are concerned. My be some of you have seen this before, for me and possibly many others its new information. Neil. DSLRvsCCD_API.pdf
  18. Yes, that's it alright, beautiful well balanced image. Neil.
  19. That's a marathon 3H 42M. M101 is a difficult object to locate, low surface brightness, then it needs lot's and lot's of time. There are just no short cuts in astrophotography. Excellent job, I'm sure you will wring the last photons out of the image later, however, it already looks good to me. Neil.
  20. First of all there very nice photo's, however, I think the first one lacks a little contract while the second one has too much! something in between the two would be spot on. In the second image my eyes are pulled first to Copernicus, then Tyco and the limb where I notice the edge. Neil.
  21. Deepskystacker should recognize your RAW files OK once you tell it which one's to use! Its an excellent program but sometimes its let down by the interface. When loading your RAW's be sure to set the correct file type in the dialog box otherwise it basically see's nothing? Normally the default file type is JPG once you set it to CRW or CR2 (CANON) you can proceed to load your images for processing etc... Hope this helps? Neil
  22. Well I guess its clear by now, what ever you do buy a CANON. I just bought the Kiss X2 = 450D secondhand for modding but I wont be doing it myself! Neil
  23. WOW... :hello1: I'm speechless... F42!!! I can honestly say that I have never seen such detail before... You can look at the last image of Ptolemaeus for hours and still not see it all. I have never had such seeing so far, push my Mewlon M250 past F16/22 is normally not possible. To be very honest using it at F11 the native focal length is difficult without an IR filter. Neil
  24. Beautiful images, did you use an IR pass filter at all? Neil.
  25. Very nice and you say that the seeing wouldn't sand any high resolution work! Can't wait ti see those images Neil
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