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Peter Rosen

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About Peter Rosen

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    Stockholm, Sweden
  1. Hi James, Sorry, I missed that you got back in June on this topic. I went to >Library >Preferences and found a file called "com.openastro.oaCapture.plist". Sometimes I also found a file called "org.openastroproject.oacapture.plist" and I have trashed both of them but it does not help to solve the problems. I have no idea were I can locate the file you are mentioning ".config/OpenAstro/oacapture.ini". Could you please guide me. I can view the created file with QT7 or QT10. If I want to stack the result I use AstroIIDC. But since this problem appeared, all the .MOV files are corrupt. Even if I capture for example 1000 frames, less than 100 will display and QT says that the duration of the film is 0:00:00. But the file size corresponds to the 1000 frames. I have tried on 2 MBP and one iMac running from 10.7.5, 10.9.5 and 10.10.5 with the same result. Everything used to work just fine with my ASI-120 MC-S and my 2 firewire cameras from TIS and suddenly it stopped working on all my Macs and with all my cameras. Thank's for your help /*Peter R
  2. Hi James, since the problem appeared I have switched partition on my computer and run oaCapture 1.0.0 on a 10.10.5 system and everything has been mostly fine. But last night I installed oaCapture 1.4.0 on that partition and all my files were corrupt the same way as I have described. A capture of 2500 frames will only allow me to stack 70 or 80 of them, the others remain invisible.! I now start to suspect that oaCapture 1.4.0 might be the origin of my problems. I am now trying to revert and have trashed oaCapture 1.4.0 and reinstalled 1.1.0 but nothing works as it should. Is there any hidden preference file that I should trash as well or do you have any other advice you can give me? Thank you /*Peter R
  3. Yes, I started using oaCapture with my TIS firewire cameras as well but since I got this corruption problems of the .MOV files in oaCapture, it also affects these cameras. On the same computer, AstroIIDC (my old Mac capture program) still captures .MOV files correctly as I wrote above. /*Peter R
  4. No, I have the problem on a MBP 15" mid 2012 with 10.9.5. Since you fixed the problem I had with debarring in the .MOV-format, I have successfully used it with my ASI-120MC-S. A friend lent me an ASI-1600 some times ago so I tried to capture some sequences in the .MOV-format. Everything seemed to work fine during the capture but when stacking I noticed the problem I describe above in my first and second posts. (I can still capture tiff files in 8 and 16 bits using the ASI-1600 with oaCapture). Since then I have the same problem when using my ASI-120MC-S with oaCapture on that Mac as something has become corrupt. If I capture 1200 frames, only about 38 appear when playing or stacking the movie. I have tried downloading newer versions of oaCapture but the problem persists. I have a second MBP 15" early 2011 with 10.7.5. As I have never tried the ASI-1600 on that computer, it still runs fine with my ASI-120 MC-S and oaCapture. My conclusion so far is that the .MOV-files have become corrupt in oaCapture since I tried it with the ASI-1600. As a side note, when I use my TIS firewire cameras with the capture program "AstroII DC", those .MOV-files are not corrupt and work fine on the first MBP. /*Peter R
  5. Thank you Reggie. I have read some articles about the Sirius system and also about the Dogon tribe, some are more or less biased in favour of the Dogons having had advanced knowledge of the system since ancient time. The article you link to gives a good balanced reference to both explanations and facts about the double, possible triple star system. Having experienced how long and difficult it has been for me to get a glimpse of Sirius B, I would favour the theory that the Dogons have received their scientific knowledge through contacts in modern times and integrated it into their ancient believes. /*Peter R
  6. Hi James, last night I photographed Jupiter using my ASI-120 MC-S camera and got the same problem as described above, i.e. Iphotographed 1200 frames but only 38 were available. I used my MBP 15" (mid 2012) running 10.9.5. As I I first noticed the problem when I tried an ASI 1600 on that computer with oaCapture, I assumed that oaCapture had a bug. I have just tested my ASI-120 MC-S on a different MBP and it works fine just as it has done before so I now think it is more likely it is something in my computer rather than the program that is at fault. Would you have any suggestions to what can be the cause? Is it possible that something got corrupted when I tried the ASI-1600 with oaCapture as everything worked fine before but not after? Thank you /*Peter R
  7. Thank you for all your positive feedback I have used for just 2 weeks now so it's a little bit early to draw any final conclusions, except for the results on Sirius B of course. I have searched the internet but there are very few good reviews and even fewer images published from people using this scope. I thought it would be difficult to handle 4000 mm as a starting point as I am used to 700 - 2350 and then I might add a 2,5x or a 4x PowerMate if necessary when everything is correctly set up but I found this telescope easier and gentler to use than I had anticipated and quickly got used to it. My first observation of the Moon last week was breathtaking in spite of a strong wavy turbulence. Just to check the resolving power, I added a 2,5 Powermate so this is 10.000 mm and I think it seems promising. On another occasion the turbulence was more high frequency and I could not get much good out of it. I used a DMK-41 mono firewire camera. I have checked all the captures from that night and Sirius B is detectable in all of them, but some need more processing. The best result though was obtained with a framerate of 3,75 images/second, exposure: 266,67 ms. To avoid getting longer exposure times I had boosted the brightness quite high to 800 (out of 1.000 and some) I took the opportunity to manually select the 40 best frames out of 1.200 and stack them in Photoshop. I also doubled the size. I am quite happy with the pinpoint shape of Sirius B and the fact that that it goes clear by a margin (5 arc seconds) to the overexposed glare of Sirius A I am glad so many of you liked the 3rd picture I had uploaded. With all the efforts to capture Sirius B, we try to reduce and control the glare of Sirius A to the point that we forget that it is the brightest star in the night sky. This image reveals the impressive glare almost right to its core. I made it in 2012 and do have it as a layered file somewhere on my hard drives but it will take some time to dig it out. Basicaly I have stacked several images starting with the brightest showing the star fields of a bigger area and successively reducing the exposure in the hope of capturing Sirius B somewhere along the way. To cope with the resulting enormous contrast, I could have tried some sort of HDR merging but I thought of another approach using frequency modulation of the luminosity of each layer. It sounds advanced but basically it just applies a curve from bright to dark several times, accentuating greatly the contrast by turning the pictures into positive-negative-positive-negative instead of just going from dark to bright. I just added the blue color because it got cooler. Here is an example on a single image:
  8. Thank you :-) Yes, I am but it is a strange feeling after trying year after year since 2012 to finally nail it. I guess I am mostly proud of how I have succeeded in perfecting the technique involved. And I was lucky that I got the opportunity to use a fantastic telescope. It all comes down to be able to concentrate the light in the smallest possible dot. I have a dog since 3 years whose informal name is Sirius B, of course, what else... But I don't use it in public places :-)
  9. Hi all, I have tried for 6 years now to capture the elusive Pup from my northern location of Stockholm, Sweden, 59,2° N, almost thinking it would be beyond my reach. Not an easy task when Sirius culminates at less than 14° and the winter season is short with a lot of bad weather. I have used a CT-10 Newton from Orion Optics UK, a FLT-110 apo-refractor from William Optics, a Celestron 9,25, with and without Powemates of 2,5 and 4x, various cameras and filters. Last week I got the possibility to have an OMC-200 Mak from Orion Optics UK on loan. The mirror is handpollished to a specification of lambda/10 and a strehl of 0,995 which is supposed to be excellent. On the 28th of March I decided to give Sirius a last try for the season at an altitude of only 8°, I used an ADC (Atmospheric Dispersion Corrector), put on a DMK-41 Mono camera and skipped all filters to be able to have the shortest possible shutter time. During the capture, I soon saw on the computer screen a little fuzzy white dot come and go close to the bright glare of Sirius A and I knew that I had succeeded at last. It can be seen approximately at a 10 o'clock position in the animation. There is a star that lies at the correct angle but that is 10 times farther away from Sirius A that is sometimes misstaken for Sirius B, circled in red in the second picture attached. The real position of Sirius B is indicated by an orange dot, well inside the glare of Sirius A. The third image was an attempt some years ago to add several different exposures and using a technique of modulation of the contrast. There is a tiny dot at the right angle and distance but it did not seem conclusive enough to me. There is always the possibility of mistaking an internal reflection for Sirius B. So during the capture I put the pair in different positions on the sensor and even turned the camera 180° to confirm that they retained their relative positions. I also photographed a wider region to get reference stars to perform the measurements of angular position and distance. I measured the distance to 10,5" and the angle measured from an horizontal line to the East was 18,3°. When plotted on a chart showing the position of Sirius B, I was glad to get it almost spot on (Red dot on the 4th image) /*Peter R
  10. Some further tests show that the .mov is in 16 bits either I choose 16bits or not. I attach the capture text file as well as 2 screen shots that show some oddities like Duration: 00:00:00 and Frame Rate: 11605.58 fps. /*Peter 06.txt
  11. Hi James, Yesterday I used an ASI1600 mono camera with oaCapture 1.3.0 for the first time. I am using a MBP 15" with OS 10.9.5. The format was MOV 8 bits and I set it to ROI 640 x 480 px. It seemed to work perfectly and I caught approximately 1.200 frames. The .mov file is about 750 Mb which seems consistent with the number of frames. But when I open it in QT, there are only 98 frames in all. Do you have any idea of where all the frames are hiding? Thanks /*Peter
  12. Thank you very much for your comments. Thank you Jonn, the amount of detail is also what made this project so difficult as even tiny mapping errors will show upp as a misalignment and double contours etc... Interestingly, in the end, the high definition is carried along by the best images while those of lesser quality merely show up as a little local turbulence, they don't reduce the overall quality the way I was afraid they would. Thank you Ron, my friend Göran Strand said about the same to me, that he could watch it for hours and asked me to put online the basic cylindrical map and the polar ones, just looping over and over again and that is the way that I like to watch them as well. In my opinion, there are so many tiny vortices at all latitudes that are thrilling to follow and you get a better understanding of the dynamics of the flows. That's basically the ultimate scope of this video. /*Peter R
  13. Hi all, Some days ago I released a new project at animating the cloudbelts of Jupiter and the GRS. In order to have an almost continuous monitoring of Jupiter, we contacted 91 amateurs from all around the world to ask for permission to use their images in this project. It took a full year and thousands of hours of work to get all the pieces in place but I'm quite pleased with the results. John Rogers, Director of the Jupiter section at the British Astronomical Association has written: "An amazing animated map of Jupiter's winds has been released by Peter Rosen and colleagues in Sweden, portraying real observations from images by amateur astronomers over 3 months in 2014-2015. The map (in various projections and perspectives) shows Jupiter's winds in glorious detail, and this is by far the best such movie ever produced from ground-based images -- worthy to compare with the Cassini movie." I hope you enjoy it It is now up and running at https://youtu.be/YZc1Y662jtk /*Peter Rosén
  14. Hi Carlos, under "Camera" you can see that your Point Grey camera has been detected and is displayed in the list but you must also click once on it to select it before you can use it. /*Peter R
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