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wimvb

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Everything posted by wimvb

  1. That pretty much sums up the situation last night. A very unexpected clear night coincided with a dinner party with colleagues. When I got home I opened the observatory, but couldn't find an interesting enough target. So I settled for a group of "small" galaxies in Lynx, close to Camelopardalis. Nest 100044 consists of about 18 galaxies and is situated about 380 million light years away. There are many other galaxies in this field of view. PixInsight found about 90 identified galaxies, but there are also a decent number of unidentified ones. One of the most distant galaxies in this field is about 2 billion light years distant. The image may not loook impressive and colourful, but shows things in a grand scale. This is 6 hours of RGB data, collected with my MN190 and ASI294MM Processed and annotated in PixInsight, with help of the TypeCat script. There is a glare of the nearby star HD 65626 in the image, but I didn't bother to remove it. Click on the image to open a larger version.
  2. Hence the title of my recent post 😉
  3. Nice! It’s a bit low in the sky for me due to trees, but your image gives me inspiration to try to catch it too.
  4. wimvb

    NGC 3628

    Great image already. Do you have a sky darkness that allows you to catch the tail?
  5. Thanks, Chris. I have several versions of the image by now. The image that I have in my first post is just RGB, without synthetic luminance, I believe. The one that I posted yesterday has a synthetic luminance and stretched somewhat differently.
  6. Reworked the image with the new version of BlurXTerminator. This version does wonders on dodgy stars, and I didn't need to crop the image. I used the combined RGB data as a synthetic luminance.
  7. I stand corrected. The vendor id for ZWO is 03c3. 0403 i s FTDI, the EQDIR cable You can see my usb list here. The first device is my ASI294 camera. The next ZWO is my ASI290 guide cam (fourth in the list), and the last one from ZWO is my filter wheel
  8. Should I go over to my image processing computer and examine my version of M33? 😁 https://www.astrobin.com/tr3ihi/B/
  9. Minor planets are asteroids and such, I think. I'm not sure about the exact differences, but I beleive that the distinction between planets / dwarf planets / minor planets is about size. The definition of a planet that I saw a long time ago was that a true planet has cleared its orbit of any other matter. Only larger bodies can do that. Asteroids / minor planets obviously haven't done so, or there wouldn't be an asteroid belt..
  10. Wasn't RASA developed for sky surveys of minor planets and other "fast moving" bodies that might come close to Earth? If so, you finally use the scope as intended. 😁 Great and surprising image, Göran.
  11. Any usb device has information about its manufacturer and model. ZWO has manufacturer code 0403 I believe. All my ZWO devices have that code when I check the usb ports. In linux (ASIAIR is based on linux), I use the command lsusb (list usb) to see this.
  12. THE hidden galaxy (not IC 342) ... with a bonus https://stargazerslounge.com/topic/416757-the-hidden-galaxy-not-ic-342-with-a-bonus/
  13. Thanks, Paul. Yes, I know of David Björkén. He used to live in the very North of the country and used the 190MN for his "portable" setup. I guess he found out that the scope is just too big if you have to set up every night, and if you have to clear a foot of snow to do so. Daniel has since moved on to a small refractor and moved to the very South of the country. The 190MN works best in an observatory or semi-permanent setup. The title of this thread is tongue in cheek. IC 342 is called the Hidden Galaxy, but with all the images of it on social media (not least AstroBin), it can hardly be called "hidden" anymore. UGCA 86 on the other hand, has so far been overlooked, even though it's very close to IC 342.
  14. Thanks, Göran. Not imaged by amateurs at least. There are just a handful of images ftom scientific publications and sky surveys.
  15. A few months ago, Göran @gorann informed me about a rather unusual galaxy that happened to be included in an image that he was working on. pgc 14241 (a nice palindrome) or UGCA 86 as it is called in the scientific literature is situated near the frequently found and imaged "hidden" galaxy IC 342. But unlike its big neighbour, this gem is truly hidden. The galaxy is situated in the constellation Camelopardalis, some 10 Mly behind the Milky Way and has a red colour as most of its blues are filtered out by dust in our own galaxy. It has an angular size of about 5 arc minutes. On closer inspection of the image, it seems that I managed to capture a few of its globular clusters as well (indicated in the annotated image). Technical details: Telescope SW 190MN with ASI294MM camera Integration time 66 x 5 minutes for R, G and B, 16 hours in total Processed in Pixinsight
  16. It doesn’t happen often here either. At least not this early in the season. February is the coldest month of the year. Yesterday the trees where completely covered with frost.
  17. The simple solution to that is a Raspberry Pi and a Pegasus Astro power box. A friend has his remote controlled setup 1.5 m from mine in the same observatory. Last summer he upgraded his computer and chose a pc next to the pier in stead of a fanless Mele on top of his scope. (Yesterday his cables were like rods). To quote Julia Roberts: ”Big mistake. Big.”
  18. Using any dslr with a mechanical shutter or mirror at such low temperature is a gamble. Otoh, modern non cooled astro cameras with their low dark current and no amp glow are a different matter. As I said in another thread on this forum, my next astrocamera may very well be such a camera, OSC with smaller pixels, used in superpixel mode. (2.9 um in superpixel mode would be 5.8 um effective pixel size. At 1000 mm focal length, this would give a very nice pixel scale.)
  19. An unexpected clear night, here north of Stockholm. The second in a row, actually. Normally I have my camera at -10 C, but that won't do now. When I just finished a session (don't want to leave my observatory open since I can't trust the forecast), the temperature had dropped to -17.8 C. I have my cooling set to -20. Now I just need to take matching darks for the rest of the night. I started imaging just after 7 pm, and managed to get 40 minutes H-alpha (wasted) and 4.5 hours RGB on my target.
  20. Excellent result. I'm starting to question the need for cooled cameras for DSO photography. The newest generation of cmos sensors with their low thermal noise, low read noise and lack of amp glow, make photography at ambient temperature a real possibility.
  21. I have to clear 8 inches of snow from my observatory before I can do any AP.
  22. Great mosaic, Göran. I wonder, if you put all your images in one big mosaic, how much of the sky would they cover?
  23. wimvb

    M33

    I'm not familiar with the uncooled 385MC. I use my 294MM at 0 gain in order to get the highest dynamic range. But it seems I'm quite alone in that. If I were you, I might test at lower gain, just above the hcg turn on value of 60. Each gain value has with it a unique offset. When the gain increases, this offset also needs to increase. I determined the best offset for my camera by shooting darks and measuring the lowest pixel values. As long as these were 0, I'd increase the offset and shoot again. For 0 gain, I use offset 8, and for 200 gain (nb imaging), I use offset 30. But because your camera has a very small sensor, it's more important that you can use the whole sensor area for your stacked image. I would look into improving telescope pointing first.
  24. wimvb

    M33

    Here's my version in PI Crop Background equalisation Colour calibration Arcsinh stretch Histogram and curves stretch (levels and curves in PS) Colour saturation Detail enhancement using MMT (multiscale processing)
  25. wimvb

    M33

    Dean, I donwloaded the fit and have a few remarks before I start processing it. There seems to be a rather large offset and some rotation between the various subs that went into this image. This is becomes apparent at the left edge and at the right corners of the stretched image. Do you use platesolving between sessions? Imo, if you don't you should start looking into it. I assume that you use a windows computer and that you already have ascom installed. In that case use NINA or similar software to control your mount. If you have to remove your camera between sessions, spend a few minutes to align the long or short edge of the camera sensor with the RA axis. Take a 30 s unguided exposure and 5 seconds in, slew the mount at 1 x sidereal in RA. This will create star trails in RA. Align the trails with an edge of the sensor. These steps will give you a better overlap between subs and maximise the usable area of the image. Second, the stacked image has a large offset. The average pixel value in the unstretched image is 0.11 on a scale from 0 (black) to 1 (white). My guess is that either the offset value for the camera at gain 135 is rather high or you have a lot of light pollution.
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