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The-MathMog

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About The-MathMog

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  1. That is almost certainly amp glow as others said. I get the same with my ZWO ASI 183MM, and it looks almost exactly like this, and I went through a whole trouble-shooting session, then only to figure out it was amp glow. Applying Dark Frames can greatly reduce these.
  2. A few things, when you say "it has no more data", are you then looking at the image straight out of DSS (or manual stack), or are you looking at a fully stretched and processed image? I couldn't see much difference in my 45 minute stack and 4 hour stack, but once processing it, I saw the difference in detail I was able to pull out immediately. And are you recording your images in RAW and not JPEG? The JPEG compression makes the image loose a lot of the very fine details that stacking lots of subs would normally bring out. And someone please correct me if I got it wrong. When you take more subs and stack then, what you do is increase the signal to noise ratio, and for that ratio to double, you need to quadruble the amount of subs you stack. So if you have an image with a total exposure time of 2 hours, then to double the signal to noise ratio, you would need 8 hours of data (correct me here, forgot if it was quadruple or double). So the longer you've been exposing a target, the more time, exponentially, you will have to put into it, to see further significant results. So you need to figure out at what point the time is simply not worth it for you. But more is of course always better Lastly, if the subs you add to a image, is actually of lesser quality than the ones you used previously, then they will actually degrade the image. Lesser quality could be that the moon was out. That there was more moisture in the air. Turbulence in the upper atmosphere. Small tracking errors. Dew on the mirror/lens, etc. Always go through your images, to sort out ones of bad quality Personally I wouldn't go far beyond 10 hours on a project, if I even ever get close to that
  3. And there indeed are people using it, but most of the time it is only the tube (OTA) that they are using. The Alt-Az mount is the main problem. I did so myself too in the beginning, but it was a lot of frustration, lack-luster results, and extra money spend, that could've been used a lot better, acquiring gear that was more suited for astrophotography in the beginning. In the beginning I didn't know that I wanted to go down the astrophotography road. The longest exposures I ever got on it was like 30 seconds, and that was after a lot of practice and calibration. As said, this mount is very flimsy and the slightest breeze or someone walking close to it will ruin your images. The mount is the most important part, when acquiring gear for astrophotography, and where you want to spend most of your money. Again, all in all, it is a very good telescope for beginners, or someone that wants something easy, light and user-friendly for exploring the night-sky visually. One that I would gladly recommend to people. Just not for astrophotography. Remember, that when you see people refer to the 150PDS, 130PDS or similar, they are talking about the SCOPE (OTA), and not what mount it sits on. They will 95% of the time use a EQ mount. The SLT by default comes on the ALT-Az. Just wanted to make that clear. Right now I have added quite a bit extra gear to my mount, with Filterwheel, Guidescope/camera, CMOS camera, Dew shield, extra counterweight to compensate for the extra weight etc. So the entire setup with tripod legs, mount, scope, all of it, weighs 35kg, so when I set it up I lift it out in two parts. The Scope part of it with OTA (Skywatcher 150PDS), Camera, Filterwheel, guidescope/camera and OTA rings, weight about 9 kilos, so well within the limits of the mount, if it is properly balanced. But all in all the setup is very quick for me to setup, compared to all the equipment I have, and I can be imaging in 30-45 minutes. If I were to only set up the telescope (OTA) and the mount, I would be up and running in way less than that. But everything is a learning curve and routines, and EQ might be harder to set up in the start, but once you get your head around it, and practice it, it is actually very intuitive and simple. A lot of people use the 130PDS with a similar mount as the AVX (Skywatcher HEQ5 or EQ5 for example), and get great results. You can see a lot of them in the thread "Imaging with the 130pds". The only difference with the 150PDS is the larger aperture (a slightly higher light-gathering cabability) and the slightly longer focal length, 750mm compared to 650mm. But the smaller size makes it more portable and "forgiving". In short, my biggest advice would be, do a lot of research (as you seem to be doing), spend as much as you can on better gear now, so that you don't have to upgrade later, and prioritize spending the most on the mount. In astrophotography, the mount is the king. Sorry for the long response, but I hope it can help you out somewhat
  4. If you wanna go pursue astrophotography and specifically deep sky imaging, you should go for a Equatorial Mount, not an Alt/Az as the Slt 130 is. When imaging on an Alt Az mount, you will get field rotation, which will make the stars blur and stretch after a certain exposure time. I made the mistake myself to start out with the Celestron 130 SLT. As good as a visual and beginner scope it is, it is really not suited at all for astrophotography. Not only is the mount quite flimsy, so that you need tuberings. The OTA itself is not set up for imaging either, as a lot of cameras doesn't have enough inward travel to reach focus. I temporarily went around this problem by introducing a barlow. But that also introduces even more optical abberations than the coma of the telescope itself did from the start. Only about half a year after I bought the SLT, I upgraded to a Celestron Advanced VX Mount and a Skywatcher 150PDS. A setup I've been very happy with. But less will do
  5. The 10 inch Skywatcher Quattro, weighs 15.1 kilograms. And that is only the tube, so when you add tube-rings, camera, guide-scope etc, it would be quite a bit heavier. The HEQ5 only has a payload of 11kg for imaging and 15kg for visual, so you would need a mount that is a lot beefier The NEQ6 (guess that is the one you meant), has a payload 18kg for imaging, 25kg for visual. Even with that you'd get close to the limits, but with proper balancing and limiting the amount of extra gear, it would be possible. An EQ6-R PRO would probably be a way better solution. But all this is of course only me looking at numbers. Things oftentimes works differently in practice, and people who've actually had their hands on these mounts/scope combinations would know a lot more than me
  6. Thank you very much Martin. These two only barely fit in the frame at this rotation. If I were to do it again from scratch sometime, I think I'd rotate the field like 20 degrees clockwise. Can't wait to add some color to it, and maybe even some HA if time lets me!
  7. Cloudless nights has been sparse the last 6 months since I got my new ZWO ASI 183MM-PRO. Probably just the prophecy holding true! But I just had two nights last week where I could get some hours in during the moonless part of the night. Unfortunately my rig had some issues on the first one, so only got like 40 minutes in, but then almost 4 hours the next night. Unfortunately I had to go to work the next day, so had to pull the plug early.. ______________________________ Gear: Skywatcher 150PDS Celestron Advanced VX Mount ZWO ASI 183MM-PRO Baader 2'' Neodymium Filter Explore Scientific Coma Corrector ToupTek Camera G-1200-KMB Mono Guider Orion Mini 50mm Guidescope Image: 4 hours 24 minutes of total luminance integration time 24 subs of 2 minutes gain 300 54 subs of 4 minutes gain 111 (unity?) Brightness/Offset 40 Calibrated with Darks and Flats Software: Sharpcap PHD 2 Photoshop CS2 Deep Sky Stacker Stellarium/Stellarium Scope Astrotortilla _________________________________ There were some rotational difference between the two sessions, so the image had to be cropped even further. Not happy with the star shapes either, but that is most likely due to me not being able to set the proper distance between the coma corrector and the camera. This is something I've fixed afterwards, so I am keen to test that out, as I should have nailed down the 55mm optimal distance. This week I got a ZWO EFW Mini with RGB filters too, so hopefully I get a few clear nights soon so I can add some delicious colors to it too. And just for fun, I've attached the stacked and processed 48 minute image I had after the first night. The background might be slightly clipped, but aesthetically that looks more pleasing to me than a more grey-ish background. I will probably do the processing from scratch when I get some rgb data on it. ______________________ 4 hour 24 minute image ________________________________________ 48 minute image Still a lot of detail in the short image, but when zooming in the noise is a lot worse, and I did really have to process the "S**T" out of it!
  8. So after acquiring a dedicated astronomy camera, the ZWO ASI183MM, and going from Backyard Nikon to Sharpcap, I've been looking into ways that I can get the program to sort the files for me with names. What I would preferably like, is for it to name the files themselves, as the target, and with the exposure length and gain, but I am not sure if and how that is possible. I've been noodling a bit with it, but it isn't as intuitive as I would like it to be. Right now it creates sub-folders: "Date/Target Name/Time of sequence start" and then the file names with the time of the exposure. It works well enough, as it also produces the text file with all info, from cooler target temperature, exposure, time you name it. But sometimes I've changed these parameters during a capture sequence, and then the text file only matches half of the actual files. Settings are changed under "File/Sharpcap Settings/File Names", if someone who isn't familiar with the program, but better at solving these issues, would have a look at it Maybe it is also just a case of me needing to change my habits, but I hope that someone has some ideas of how I could change the file naming. Thanks for your time, and if there is a better sub-forum for this, please redirect it! ///Mathias M.
  9. My guess is that you would have to use sidereal when training. But not having said controller myself, it is hard to say. I did find the manual for it online though and the procedure is as stated. 1. "Polar align the equatorial mount accurately, and then perform a star alignment". There is an answer for your first question. You need to star align. 2. "Choose a star close to the celestial equator, point the telescope towards it and start mount tracking. Center the star in the telescope's eyepiece" - this is where I am pretty sure you need to just use sidereal tracking. 3. "Access the menu - "Utility Function\PEC Training" and press ENTER. Press 1 or 2 to select the guiding speed. 4. "The screen will display the elapsed time. Use the left and right direction keys to control the mount and keep the star at the same spot in the FOV of the telescope until the SynScan HC stops displaying the time. The total time for this training process depends on mount models." and then to activate the PEC, you do indeed go into "Setup\Tracking\Pec+Sidereal". So, if you followed those steps, I can't see why it would not work.
  10. What constitutes it being a disaster? Is the images just completely black, or is it all out of focus? Starting out, it is indeed a good idea to focus on the moon, as the focus will be pretty much the same for everything else in the sky. But the moon is also very bright, so camera settings will need to be very different for other objects. Way longer exposure and higher gain. As mentioned too, your mount is an Alt-Az mount, and is decent enough for photographing planets and the moon, but it gets hard when trying to do Deep Sky Objects. It is possible though. I started out with an Alt-Az mount too, and found the longest exposures I could do was just short of 30 seconds. Enough for some of the brightest objects, and getting your head around astrophotography. But if astrophotography is your main interest, then you should eventually look at getting an Equatorial mount and even a telescope with a shorter focal length, but as you said, don't do that quite yet. Get comfortable with your current setup, and spend time learning and observing. Figuring out what your expectations are
  11. Welcome to the forum! I've only been on here for almost a couple of years myself, and I can attest to, that there is a lot of help, experience and opinions to help you along the way! Clear skies!
  12. PEC seems to one of those areas that either works wonders for people, and for some it is a "waste of time" disaster. For me, it worked wonders, and actually improved my guiding a lot. But that was also because my mount did have a lot of periodic error, that the guiding now doesn't have to work as hard to fix. I did have to have a very good polar alignment, and do half a dousin training sessions and then average that data to get it to work how it should. But that also took my from loosing about 1/2 of my 2 minute subs, to be able to frequently pull of 4 minutes of unguided subs. So, I still wager he should at least give it a go. But yeah, if your mount doesn't have serious issues with PEC anyway, guiding would almost always be time better spend
  13. I've had great experiences with Skywatcher, as I am currently using the 6 inch version "Skywatcher 150PDS" on a Celestron AVX Mount. What you need to figure out for yourself is, what focal length and targets are you looking at imaging? The TS optics is a 800mm (F4) focal length, while the Skywatcher is 1000mm (F5), so the TS has a larger field of view, but is also more demanding in terms of precise collimation. On the other end, the Skywatcher is a bit heavier because of the difference in length, so will be slightly more demanding for your mount, (but probably not by much, and your mount should easily handle it), while the length is also more susceptible to get affected by wind gusts. And tracking errors in general are of course amplified too. I do recommend the Skywatcher though. They are great quality scopes for the price. Haven't had hands on a TS though, but if they are in the same range, I would pick the scope that matches your desired focal length I'd search the web dry, for references and experiences on that scope.
  14. I've had my fare share of issues with PEC myself, mostly because of actual bugs and file format discrepancies between the mount and the software, but have now gotten it to work mostly! ? I do have a Celestron AVX mount, so I am not sure if I can be of any help, but I can at least try. On my AVX, I need to do a "Star-align" to get it to work, but that is because I can't really access the telescope without it. I can of course just do a "quick align", which just tells the scope it is in parking position. The reason really just is, that without the align, it isn't tracking in RA. How do you do your PEC-training? Do you manually guide on a star for the period when training, or do you auto-guide? And just to make sure, you do need to be tracking when training PEC. Is it only PEC that stops, or is it tracking in general, after 5 seconds? If the star literally starts to drift, it sounds like tracking too. On the note of "Choosing other items in the menu "Setup\Tracking" will turn off the PEC", you say that you DO choose another item, and that you think it is strange that it turns off PEC. But that is what it says it will when you do so. Or did I misinterpret that? My mount keeps on PEC even when exiting the PEC menu, but it sounds like this mount only have it activated when "PEC + Sidereal" is chosen. Quite a few questions, but clarifying those might help get to the culprit of your issue ?
  15. A new camera, means a lot of testing and seizing every possible clear night at your disposal. I used the first nights with my "ZWO ASI183MM-Pro" shooting hydrogen alpha, but now I wanted to test it on a broadband target. And what better test-subject than good old Bode's Galaxy/Nebula, for this image size! Upon processing the 3,6 hours worth of luminance data, I then realized that I missed the color in the image. So I went digging for the last images I shot of M81, which was with a Nikon D5200 sometime last year. I aligned the images and set the old image to color, and got this as my final result. I must say though, that I've probably gone through 20 different renditions of this one, as I kept trying to improve it, and finding a new favorite image But here is the last one I came up with, together with the separate luminance data and the 2017 M81 image Upon further investigation, I've noticed some dust-motes that has snuck into the image... Guess I need to figure out how to do flats.. They were never really necessary when shooting with the DSLR as noise would be too high anyway if you stretched it this much. Shot with: ???? Skywatcher 150PDS ZWO ASI 183MM-Pro (Nikon D5200) Celestron Advanced VX Mount Explore Scientific Coma Corrector Baader Neodymium Filter 213 Minutes Luminance (4 Minute + 8 Minute Subs) 136 Minutes of Color DSLR (2 Minute Subs) Combined Image (5.816 hour data) Luminance Data (3.6 hour data - ZWO ASI 183MM-Pro) DSLR Image (2.26 hour data - Nikon D5200) Any advice or thought are accepted with open arms! One thing I know myself, is that I need to improve my mounts PEC data-set, to improve my guiding. It worked very well when I first did it, but that is like 1,5 years ago now.
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