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Dom543

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Everything posted by Dom543

  1. I have had a Samsung SCB-2000 video camera for three years and that conditioned me on colour. I felt that the extra sensitivity of the mono was not enough to compensate for the sense of loss inflicted by the loss of colour. Also the X2C became available in the summer and ahead of the fall, which are the seasons of colorful nebulae. So I bought the X2C. Had we been in the winter/spring galaxy season, I might have given a more serious consideration to the mono version. --Dom
  2. Thank you, Don! Your Bubble is very nice. Yes, I used 5 darks for the last image. Darks are very easy to take with my flip mirror set up. No need to cover the scope. I take the darks, while the mirror is flipped to the eyepiece and I finding and centering the object. Here is a photo of my flip mirror with LSX2C <http://www.cloudynights.com/topic/144287-post-a-picture-of-your-assisted-visual-setup/page-14> #335 towards the bottom of page 14 or Post #6210685. My earlier image, that was made from a single frame has quite a few hot pixels. The yellow and magenta ones are particularly noticeable. Comparing the earlier single frame image with the most recent dark subtracted one shows how well Paul's darks and stacking work. --Dom
  3. Thank you, Paul and All! It cleared up for two nights last weekend. Below is my most recent attempt on M27. The LL settings were the same as described above. But this time it was live capture, not reloading an earlier captured FITS file. This way I could mean-stack 12 frames 60sec each. The result is a much smoother image. The alignment and stacking works very well in LL. I also used an IDAS LP2 filter. It helped to suppress many of the overwhelming background and foreground stars and to make the background darker. This way the nebula jumps out better from the background. Apart from the IDAS filter, this image is also filtered through the moisture-rich September atmosphere of Seattle. This time I managed to capture some of the cyan of the interior of the nebula. But nearly not as much as HiloDon from from under his Hawaii skies. I also managed to see the Crescent and Bubble nebulas on my screen. But the shots are too faint and pale to be posted. Clear Skies! --Dom
  4. Nice shots Don! Even on the unprocessed M27 you got more teal than I did with twice the exposure and several stops faster optics. It may simply be the case that the atmosphere here in Seattle is filtering out some of those colors. It clouded up here now so we may not see any more photos from Seattle until July 4. Next week I'll go back to New England and will try from there. LL is a very nice product and opens up entirely new horizons for the Lodestar. My input is user feedback, not criticism. --Dom
  5. Hi Paul and All, After my attempts yesterday (see http://stargazerslounge.com/topic/225395-first-light-with-lodestar-x2c-and-llive/ Post #8), I did more thinking about how one could increase colour saturation. The final conclusion reached is that it would be difficult, if not impossible, in RGB or in any system that doesn't have an explicite luminosity component. The reason is that colour saturation is a variable that is (should be) independent of luminosity. So one needed a way to keep luminosity constant, while increasing colour saturation. In RGB, when we increase the brightness of any of the colour components, that automatically also increases luminosity. The best way, I could come up with involves temporarily changing into the cylindrical HSL coordinate system. In this system the axial coordinate measured on the perimeter of the circle/cylinder is hue, the radial component is saturation and the axial component is luminance. The plan of action would be as follows. 1. Convert every pixel's RGB values into HSL coordinates. (There is a formula giving one-to-one correspondence.) 2. Increase the radial "saturation" coordinate of every pixel by the desired multiplier (ideally, implemented with a slider). 3. Convert the new HSL coordinates back into RGB. I believe that the additional computational burden should be managable for the relatively low number of pixels of the 1/2" sensor. If not, then we could think about figuring out the formula, that does the same but directly in RGB coordinates. I am not sure though, if this offers any real saving of processing time. All three coordinates of all pixels will still need to be recalculated. As an example, a not fully saturated green pixel also has non-zero red and blue components. Increasing saturation means increasing the green component and, at the same time, decreasing the red and blue components so that the overall luminosity of the pixel remains constant. Cheers! --Dom
  6. Finally, here is a slightly darker version. --Dom
  7. Hi All, This is my second try. I used one of the subs that were stacked to get the image at the beginning of this thread. Then I did my best to mimic that Paul said v.011 will do. Here is the outcome. Here are the steps that I took. 1. Loaded FIT file that was saved by LL during the observing session three days ago from the "Run" prompt with the command <full path>\LodestarLive.exe -args -<full path>\<filename.fit> 2. Found the center of the dynamical range by moving the "Black Level" and "White Level" sliders to the point, where their position indicators on the right of the sliders displayed the same numbers. 3. Checked the "Modify all" box and moved all three histogram spikes to the center of the range by increasing gamma (to about 3.0). The red one ended up slightly on the right side of the center, the blue and green ones on the left side. 4. I fattened the histogram spikes by pushing up the contrast slider to its maximum position. 5. Moved the "Black Level" and "White Level" sliders to their original end positions and unchecked the "Modify All" checkbox. 6. Moved the three histogram spikes to a position, where their maxima overlapped exactly. This is done by checking the radio button of the respective colors and moving the "Brightness" slider up or down. 7. Moved the "Black Level" slider up to as close to the beginning of the now overlapping histogram spikes as possible. Moved the "White Level" slider down as far as I could without creating a whiteout spot inside of the nebula. This is all. One difference between the image at the beginning of the thread and this "improved" one is that the recent image was created from a single FIT file and with no darks subtraction. The original image had a master dark made of 5 exposures subtracted and was the result of mean-stacking of 10 frames. Cheers! --Dom
  8. Hi Paul, The videos are very helpful. Thank you! Is it possible to download them from somewhere? So that one can watch them off-line. Is it possible to stack multiple FITS files in test mode? I have several hours of fits files from the other night. It would be nice to play with them as the clouds have now moved in. I would also be happy to send you some FITS files, if that would help. And if you let me know, where to send them. Thanks again, --Dom
  9. Hi Greg, I have cousins in Victoria BC and nephews and nieces in Port Hardy, Port McNeil, Campbell River and other forestry towns on the Northern part of Vancouver Island. I bought my CGEM from a guy in Nanaimo. He turned solar... The magenta tint is due to the fact that the red histogram spikes are to the right of the blue and green ones. You can move the histograms of the individual channels by first selecting their respective radio buttons on the bottom of the page (with NO checkmark in the "Change all channels" box). Then increasing "Brightness" moves the spike of the selected channel to the right and increasing "Contrast" moves the spike to the left. Doing this carefully, one can nudge the spikes to overlap exactly. That yields a neutral color balance. Also, you need to move the "Black level" slider up to as close to the beginning of the histograms as possible. And the "White level" slider down as far as you can go without getting too bright of a background. In my case, the space between the two sliders is approximately 20% of the total available dynamic range. I assume that your air is just as moisture rich as ours here. But you probably have much less light pollution. I have a straight view of downtown Seattle about 2-3 miles away across Lake Union. I see the city lights both directly and also reflected over the water... Those are the filters I meant. I don't know what they are for. Enjoy the nice clear nights, while they last! Cheers! --Dom
  10. Hi All, Yesterday I managed to get my first properly color balanced shots out of my new Lodestar X2C with LLive v.0.10. Thank you HiloDon for the advice. Here is the best I could get out of M27. The 60 sec integration seems excessive but was necessary under the September skies of Seattle. The sky here was clear but the air was full of fine moisture and not transparent. One could barely see the bright alignment stars that the CGEM mount uses. And M27 was not visible in the eyepiece of my 10" Meade OTA. I had to center it in the field using the nearby stars and averted vision. This was, actually, my second try with the new camera. The day before I got images straight from the Beatles song Strawberry Skies... This time I nudged the histogram spikes of the three colour channels to overlap using the brightness and contrast sliders. I don't exactly know what gamma goes but this image with gamma=2 looked better than with the default gamma=1. My #1 desire would be to increase color saturation. If anyone knows a trick how to achieve that, I would really appreciate it. I have not tried those filters in LL. Could they be useful for this purpose? My #2 wish would be to have rolling sum-stacking in LL. So that one could set the maximum number frames and always the most recent this many frames would be summed. The registered stacking works very well in LL. In fact, better than the tracking of my mount. Fixed-number-of-frames sum-stacking would allow to limit single exposures to 30 sec, or whatever the tracking of the mount allows and synthesize the longer exposures through sum-stacking. Anyway, big thank you to Paul for LodestarLive and similarly big thank you to SX for this very fast and sensitive modern camera. Cheers! --Dom
  11. Hi Don, I am new to LL and have two newby questions. 1. What exactly are you doing to adjust color balance in the histogram? What steps? 2. What is "two finger swipe"? Thank you, --Dom
  12. Thank you Piotr / riklaunim ! Your insights are very helpful. The pieces now start to fall in place. My interest in the Opticsar DS-616C XL was motivated by the fact that the same Tucsen TCC-6.1ICE camera is used as the starting point for the new Mallincam Universe. According to posts by Rock Mallin, his design transforms the base lab camera to a spacialized astronomy device through the following three main contributions. 1. Replaces the standard ICX413AQ sensor by a hard to get laboratory grade version that has fewer defects (Class 0), higher sensitivity (1250mV) and can be chilled more aggressively (-45C) to generate less noise. 2. Replaces the stock amplifier of the lab camera with his own low noise and high gain "hyper circuitry", adapted from his Mallincam video cameras. 3. Boundles the camera with a self-contained control and capture software designed and developed specifically for the astonomical use of the Mallincam Universe. A feature of the software is that it allows near live views of sufficiently bright objects. Based on what you Piotr said, it seems that the low noise high speed electronics is really one of the crucial elements that is needed to make the difference between a lab and an astro camera. Of course, all the nice things come at a price. The US introductory price of the Mallincam Universe is $1900. For comparison, the US list price of the Opticstar DS is $1300, the QHY8L is $1300 and the QHY8pro is $2100. As far as I know, about 20 MC Universes have been delivered to date and perhaps another 30-50 will be made before the end of the year. Many of the cameras from the initial batch went to devout users of the Mallincam video cameras, who want to use their Universes as the tool of entry into serious CCD astrophotography. Since most of these buyers are novices to AP, it will take a time until the MC Universe can be evaluated based on images made by experienced astrophotographers. I am neither a secret salesman nor an agent of a competitor of the Mallincam Universe. I am only listing the above facts for the information of other readers of this thread. I don't want to hijack the thread but it seemed that this info may be of interest to those, who are looking at the Opticstar DS. Thanks again for all the input this far. --Dom
  13. Thank you riklaunim! I am still at the early stages of the learning curve. It would be helpful to me, if you or someone else pointed out what is wrong with the following argumments. 1. Lab cameras are made in large production series and can hence be made available at economical prices. 2. 12 bit means less color depth than 16 bit but, on the other hand, allows faster downloads. 3. Why do we need all that ultimate color depth in asto imaging? There is more "color cheating" happening as a result of the use of filters and of deliberate shifting of color balance during processing. Thanks, --Dom
  14. I was about to ask the same question about the Opticstar ds-616c xl. Since Opticstar is based im Manchester UK, I was hoping that, if anywhere, I could locate users of this camera on these forums. The first ten pages of a google search in the US list only three URL's that are not opticstar.com. Oceanside Photo and Woodside Camera list the opticstar ds-616c xl on their retail pages. But inquiries about actual availability yield the answer that "We are eagerly awaiting this camera". Farpoint Astro, which is the third outfit listing the camera replies that "We no longer carry this item". So one is wondering, if this is a real camera that anyone is using. Or just a pre-announcement that may or may not ever become reality. Any further insight would be appreciated. --Dom
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