Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Welcome to Stargazers Lounge

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customise your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more! This message will be removed once you have signed in.

  • Announcements

    sgl_imaging_challenge_banner_jupiter.jpg

     

Jannis

Advanced Members
  • Content count

    1,591
  • Joined

  • Last visited

Community Reputation

554 Excellent

4 Followers

About Jannis

Contact Methods

  • MSN
    dj_janis@hotmail.com
  • Yahoo
    janerikjohansen@yahoo.com
  • Skype
    jan-erik-86

Profile Information

  • Gender
    Male
  • Interests
    Astronomy, Anime, Electronics and Photography
  • Location
    Gamle Fredrikstad, Norway
  1. Received some feedback that i had been a bit too careful with the processing, so made a v2 with darker background, a bit more noise reduction and stronger sharpening. Still not sure which one i like best...
  2. Correct, in PS just select select 200% size for the images that you captured with 2x2 and save. DSS should then be able to "stack" (or simply align) the channel images for you. If you used a filter wheel for the channels and haven't changed the camera position at all you might also simply resize and align manually in PS though.
  3. Thanks guys! I'm impressed with what this camera can deliver as well. Even though it requires more work then when imaging with the QHY5L-II, I'm very happy i didn't give up trying to use it for imaging. It have already improved my M51 significantly, this M63 turned out very nice also, and my ngc 6946 from last night also appear to have turned out really nice despite the short exposure time and lack of complete darkness in the night. I'm hoping for an upgrade in the future to a proper camera (one actually intended for imaging, and not polar alignment), but for now i can't even afford RGB filter, so I'll just have to keep trying to pull out every photon possible from my current equipment..
  4. The dark season in Norway is officially over, there is no longer any "astro" dark time during the night. Still, with no moon and a couple of hours with more or less dark skies, i though i might as well give it a go, and it turned out much better then i had though indeed! This is another round with LRGB, where the RGB data was captured with the 550D right before sunrise, and the L data was captured with the QHY Polemaster camera. I've changed my approach a little this time though. Previously I've gone for gain 30 and 60 sec exposure, but seeing as my tracking and seeing were rather poor this night i went for gain 100 and only 15 sec exposures. This resulted in a noticeable sharper end image. I wanted minimal data wasted, so i made 2 stacks. One with 50% best frames, and one with 95% best frames. The 95% best frames image was then only applied for the background to reduce the noise. L data is 605x 15 sec at gain 100 + calibration frames (222x dark, 250x flat, and 500x bias) I only managed to capture 12x 180 sec RGB exposures before the sky got washed out, but any color is better then no color. Total exposure is 3 hours 7 minutes.
  5. That's a really great start! If you're able to take 120 sec exposures unguided with reasonable round stars at 300mm then that mini mount is better then i thought it was, and you can for sure use it for many many targets! Your image looks really nice, just capture more data to increase the details and lower the noise. I recommend that you take more calibration files though. Although 4 darks are better then 1, or none, i would aim for a higher number to get a more accurate average. I'd say 20+ if possible (if you took the light at ~+4c, throw the camera in the fridge and let it take darks until it runs out of battery ). Canon DSLR normally have strong random banding noise, and so the problem with too few calibration frames is that you risk removing actual data from the image instead of just the constant noise / hot pixels. Just make sure the temp and ISO is the same. A warmer sensor will have more noise and hot pixels, so if you take darks at a higher temp, you'll end up removing actual data from the image. Darks taken at a slightly colder temp is usually fine as far as i've understood (someone please correct me if i'm wrong), it just won're remove as much noise as it could have if taken at the same temp.
  6. Guys, am i understanding it correct here that this supernova is in fact not in M63 after all, but if from a galaxy far behind it? If my understanding and math is correct this supernova is from around 1000 million light years away?
  7. It looks pretty good if you ask me. A way i smooth the background only with a gradually less and less aggressive noise reduction for the brighter parts, is that in PS: 1) I duplicate the layer 2) Copy the whole frame and paste it into a layer mask 3) Invert the layer mask (so that the background is nearly white and the brighter stars nearly black) 4) Click on the duplicated layer again and run a very strong noise reduction (don't be gentle with it like you usually would be, as it will only affect the darker parts of the image) 5) if it affects too much of the brighter parts of the image, or too little of the darker parts, adjust the levels on the layer mask only to adjust how the noise reduction will affect the image. Now you can just check and uncheck the processed layer for comparison - I find it a lot more easy to see if you've over or underdone the processing that way. 6) If you're happy with it, apply layer mask and merge down.
  8. So i was looking around the forum for images of M63 and compared with my own. I came across Barry-Wilson's awesome M63 image and decided to do a more detailed comparison with my own and aligned the images. I noticed i still have miles to go to get to that detail level, but i also did notice something else...! I first thought it was a hot pixel or other artifacts in my image, but then thought it simply can't be - it's shape and size is way off for that. I then compared it to The-MathMog's fresh and nice M63 image as well to confirm, and sure enough, the bright "star" was in his picture as well! After some googling I think I've captured Supernova 2017dfc. I wasn't the first to notice this one though, but i don't think many people have captured it yet either! I hope you guys (The-MathMog and Barry-Wilson) don't mind that i copy a section from your images for comparison? This is my image from the 17. and 18., of April 2017: This is The-MathMog's M63 (from the 24. April 2017?): And this is Barry-Wilson's M63 (from between 1. February and 2. April 2017?), snowing no SN at all:
  9. Thats a really nice capture there! Quite sharp and lots of details, especially when concidering the relatively short total exposure and equipment used (and even unguided if i understood well?)! Edit: I think you've also managed to just capture the Supernova 2017dfc!
  10. If you in DSS selected "standard", instead of "intersection" or "mosaic" the 2x2 bin frames should be exactly half the size of the 1x1 bin frames. This simply mean you need to double the size. Can be done in most programs, even MS paint. DSS is very picky indeed. Just 1 pixel off and it won't stack and align, so it's critical they are identical. Because of this I also tend to stack data separately and use registar for aligning, but it's not a free program. I haven't tried this myself, but if you have enough frames, it could maybe work to check the "2x drizzle" option in DSS for the 2x2 BIN files? It will create a 2x sized image, but naturally at the cost of SNR. If it works it could both simplify the process of resizing and also maybe recover some lost resolution (unlike when resizing afterwards).
  11. Thanks guys! It was more difficult to capture this target in details then i had thought, but considering the equipment used and not ideal seeing I can't complain. Göran, I agree, I think i was a bit too aggressive with the sharpening and pulling out the fainter data that was hiding in the noise. Does this look any better? It looked very blurry to begin with, so i used quite a bit of sharpening. This is the L data with just some quick levels and curves before any sharpening. And correct, the L data was captured with the Polemaster. It used the same sensor as the QHY5L-II-M / ASI120MM (MT9M034), but without the automatic FPN removal. It's not an ideal sensor for deep sky i guess, but for brighter targets it give a very good results for the money I'd say - if you just get enough exposure.
  12. M63 looked like a really nice little galaxy, but my multiple attempts to capture it with the 550D did not give results i was looking for. Recently I've started using the Polemaster camera more and more for imaging once its polar alignment job is done, with great results on for example M51, and so i thought I'd give this target a go as well. M63 turned out fainter then i expected, but let the camera run for 2 nights anyway, capturing a total of 9 hours L data, and added some earlier data from the 550D as color. Only the cropped area contains the L data. I'm quite happy with this image for now, but i hope i can improve it even more next season. Captured with the Explorer 200 on the HEQ5-pro mount, guided by the QHY5L-II-M. 2 hour 35 minute RGB: 31x 300s, ISO800 with Canon 550D - flat dark bias added. 9 hour L: 540x 60s, gain 30 - flat bias added.
  13. That looks really nice if you ask me. I would maybe prefer a bit stronger colors, but not sure what your data will allow you to drag out?
  14. That's indeed a nice and colorful image from only 30 minutes! Some darks to remove the hot pixels you make it even better though, as they disturb the picture a little. I'm also interested to see your previous image for comparison between dark and suburban sky. I've always captured in an orange sone, and with a not so mobile setup I've just tried to beat it with more exposures.
  15. I usually take my flats the morning after where I've left my camera attached and the focus locked. I shoot straight up into the sky before the sun gets up, but after the brighter stars are no longer visible. The minimal focus change caused by a few degrees temp change is so small it haven't seems to affect any of my images at least. As far as before/after flip i can't really say I've ever even thought about that. Dust that is stuck doesn't care about flip, and very loose dust will probably not return to the exact same position even if you flip it back for flats, but i don't know, maybe there are other reasons why people want this...?