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The-MathMog

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About The-MathMog

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    Nebula
  • Birthday 29/08/93

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    Male
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    Denmark
  1. Sorry but I don't have a solution to getting dss to work that out for you. But why not just manually stack the two outputs, the stacked 30 second frame and the stacked 4 min one? It can easily be done in either photoshop or gimp which is free and then you can also experiment with different opacities, to either favor more of the 4 min data or more of the 30 second data, or only using the 30 second data for the cores. The stacking itself can easily be done with the blending modes, where "difference" mode is a great tool, and then turning one layer on and off to see if they line up properly
  2. Alright then. I did have quite a lot worse coma when I put the barlow closer to the camera. That was quite horrendous. And yeah this is actually a full frame, at least the first image. Right now I am stuck at using the barlow lens, for focus reasons, at least until I can find a place that sells the right screws for me to move the primary mirror up the tube. From what I've heard and read, is should be about the equivalent of the HEQ5 mount, with maybe a slightly lower payload. Definitely I will! At this point I've been able to get some 3 minute unguided subs, but the periodic errors make me throw out at least 3/4 of them. I absolutely agree. And processing is something that I am looking quite a bit into at the moment, using the tools I have available (I don't wanna spend more money than I have to at the moment :p) I actually don't have the original RAW files anymore, as I had to convert them into a usable file (Photoshop wouldn't handle the NEF file from Nikon), so I only have PPM files, which is around 4 GB of data. I don't have that much space left on my dropbox unfortunately haha! But if you wanna have a go at the final stacked image, be my guest! https://www.dropbox.com/s/op2q56k1mvvwsly/Last Stack 60 Images.tif?dl=0
  3. Haha indeed it was a intense! It was all done in Photoshop CS2. Stacking, subtracting darks and stretching. And you might be right. But that sub example was also one of the better subs, most of the subs had worse data or worse stars too because of the wind, which is also apparent in the final image as I just used all the frames, making them all "stretch and blur" in one direction. Processing the images is still very new to me, so a bit of a learning curve, and as of right now, I try to not overdo it whenever I do it. A coma corrector and auto-guiding is indeed my next step in astrophotography, so your estimation isn't all that wrong, as I will probably get those in a month or two. The bank was just broke with the AVX mount last month, so it needs to recover a bit hehe. Whenever I try to do longer subs than 1 minute I will often see what looks like periodic errors, at least not a consistent star trail, so guiding is something I'll be looking forward to, as well as doing Periodic error correction. The coma might also be enhanced by the use of the barlow, or is that a wrong idea? And was it in the initial photo that you see the coma?
  4. Went out Tuesday night to do some more practice with my new Celestron AVX mount, as a clear night was predicted. I wanted to improve my polar alignment and tested drift alignment for the first time. It came out very well, and I thought that I'd better not let it go to waste, so I went on to capture M51. The thing is though, I had neglected/underestimated how much wind there would be that night, and it got horrible very quick. The medium wind (according to weather stations) was around 10m/s with gusts being more than that at its peak, but stubborn as I was I just endured it, knowingly that the a lot of the subs would be straight for the trashcan. On top of that, it was 1.5-2 days after the full moon, so the sky was veeery lit up, proving even more of a challenge. But again, the lack of clear skies lately, made me not want to waste it. So I ended up gathering around 64 frames of 1 minute at ISO 6400. I did try doing 2 minute and 3 minute exposures. They didn't show much trailing, but were a lot more prone to the strong gusts that made the stars jiggle, so I kept to doing 1 minute subs. And even out of those, only around 4 subs were decent without much traces of the strong wind.. Of course deep sky stacker didn't like my horrendous shaped stars, so I went on to stack 60 of them manually (at this point I didn't care about the shapes of the stars, I just wanted to see what data was hidden in it), stacking 5 at a time, and then stacking those 12 stacks 4 at a time, and then the last 3, for an estimated total exposure time of 60 minutes +- (as I was using a remote without a timer).. Nonetheless, this is what one of the better subs looked like, and what eventually came out of it, and I am glad that I could at least pull something out of this, and this just makes me want to get out and shoot even more (preferably on less windy nights)! 60 Subs (1min+-) 60 Min Total Exp ISO 6400 20 Dark Frames Celestron 130 SLT OTA Celestron AVX Mount Baader 2.25 Barlow (For focus) -Mathias
  5. Rookie question. What does the QE percentage stand for?
  6. And to add on to the Bahtinov mask suggestion. You can also create one yourself. Just find a template with the correct size online. Print it out, tape/glue it on top of a thin or thick piece of cardboard and then cut out the holes with a utility knife. Then it is just about adding a few pieces that will hold it in place. It takes a bit of time, but is easy. It might not be AS accurate as one made professionally, but it will still produce the desired spikes.
  7. Indeed haha, forgot that minor important part
  8. I recently got hands on my first equatorial mount, a Celestron Advanced VX mount.. And the curse holds true, that after purchasing new gear, you are to bear the burden of weeks of bad weather! So whenever there has been minor holes in the clouds, I've been out practicing star alignment, polar alignment, and just the general behavior of the mount, pointing at any star that would glance through the thin cloud cover. Hope to soon be able to practice drift alignment. A patch of "clear sky" showed itself a few nights ago, so I thought I would try and see how far I could push the unguided exposures (having only done the ASPA). And even though thin clouds would regularly pass over the target, I am at least pleased that I could squeeze this out of the image. +- 1 minute exposures of the center of the noble M45, Pleiades. 5-6 shots later, the clouds came rolling in again... So here I am stuck looking at my mount collecting dust and browsing these forums again Looks like there is some coma that needs fixing too. Scope is the Celestron 130 SLT OTA. Using a barlow right now to achieve focus. Trying to obtain the screws needed to move the mirror. As a bonus, I noticed the presence of a magnitude 17.2 in this one, faintest I've caught yet I think.
  9. From the album The-MathMog's Images

    Taking advantage of a short break in the cloud cover. Although a thin layer is still present.
  10. The shape of the stars very likely is a case of, sub length being too close to the limitations of the tracking accuracy. Drifting, if done thoroughly of course, will be a lot more accurate than by using polaris as a guide. But nice pictures nonetheless. For 1 minute subs you are at least somewhat polar aligned. I know for one, that my images didn't look like this, after my first nights with an equatorial mount Your background is quite black too, so I think you could also try increasing the ISO and then maybe decrease the exposure length, to improve the star shapes. And then of course shoot several images that you then can stack. Even just stacking say 2 or 4 images will greatly improve an image. Other things to consider is, without guiding, periodic errors in the gears can become a bigger issue with "longer" subs, making every "x" number of image not perfect. And lastly, wind could also be a cause, (if it was windy of course), even for a good steady mount. But great work! I am a bit in the same boat as you, having started with astrophotography not too long ago and gradually learning every nook and cranny of what can make a better image
  11. All you pretty much need to get started is a T2 ring, if you don't have one, specific to the brand of camera you have, canon in this case, and a T-Adapter if your scope doesn't have threads that lets it connect directly. Like this https://www.firstlightoptics.com/adapters/t-rings.html
  12. Drift alignment as mentioned, is a possibility, as all it really needs is a camera capable of doing exposures of a few minutes. And it can be really accurate depending on how much effort you wanna put into it, and it takes software calculations (All Star Polar Allignment for example) out of the equation. And to the original post, it sounds like an interesting feature. Are you just using your main imaging camera, or how do you go about it?
  13. Not really good at processing either, but I figured I would give it a try anyway, just as a practice routine for myself nonetheless. This is what I could bring out of it. And I cropped it a bit, as the image had some stacking artifacts at the edges Test Process.tif
  14. +1 for happy-kat's suggestion. They are quite simple and very useful, and can also be found on youtube.
  15. Here is a list of stars that you could try out http://www.universetoday.com/111716/14-red-dwarf-stars-to-view-with-backyard-telescopes/