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LOL221

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Everything posted by LOL221

  1. As requested, heres my Astrobin Gallery. https://www.astrobin.com/users/LOL221/ These are not all DSO's i shot yet, but i got so much data to process... I think ill need the next 2 months haha.
  2. thats what i thought. Thats why im checking thrice on everything, cant afford to waste my already low balance.
  3. oh haha, i already posted in that thread. But my images there are through a completely non-tracking 8" Skywatcher.
  4. Its not the only one that fits my D3400, and yeah the filter is by STC, but the transmission chart seems to show exactly what i need the filter to do. I was acutally quite surprised that there are clip filter for the D3400 because last time i looked, there were none. My Alt-Az Setup actually isnt all that bad. Yes, with the 660mm focal lenght im limited to 30 seconds (+- 5 sec depending on conditions) but it works better than i thought it would. I will upload my images to Astrobin, will post the link here later since it takes a while.
  5. Yes, that helps massively. So Ha is not part of IR... I shouldnt ask the facebook groups anymore, or atleast confirm every word they say with reliable sources. Yes i want to take Broadband color images, basically just like the stock camera would but with higher red sensitivity and no IR or UV bloat. So the Multispectra filter will work. Thanks a lot, i got it now. This is all very confusing to me, especially because im a complete beginner when it comes to modded cams.
  6. The people in Facebook's Astrophotography groups told me something completely different. Am i just too dumb to understand this? I removed the ICF (aka the stock filter that comes with the camera, infront of the sensor) and now have to replace it. I do not want to do narrowband imaging. I do not want to capture a single emission line on its own. And again, would the STC MultiSpectra filter work? All i need is a filter that blocks the invisible part of UV/IR but lets the Ha, Sii and Oiii emission lines through. Is that what a UV/IR cut filter will do? Ha is part of IR so wouldnt a normal UV/IR cut filter just cut the Ha line off?
  7. First of all, neither mount or scope are suited for AP but i got some impressive results for what they are. The Scope is a Nexstar 102SLT on its stock AltAz mount. No lenses, except for barnards loop but thats it. Prime focus, T2-ring screwed to large end of eyepiece holder and then into the scope. As stated, my original plan was to get rid of the stock filter and replace it with a filter that lets Ha through, BUT i dont want to do narrowband imaging only. Thats why i linked the STC Multispectra filter because it seems to do exactly what i need it to do.
  8. So a Clip-in Multispectra filter for my D3400 would be better? Im not using my DSRL for daytime photography anyways.
  9. Thank you so much, but i cant find an Astronomik Clip filter that fits Nikon APS-C. Can you recommend any brands?
  10. Aloha Astrogang. Yesterday i successfully Full Spectrum Modified my Nikon D3400 and instantly had a chance to try it out. The oiginal plan was to Ha mod it but i didnt have a filter to replace the stock one with... I kinda already knew a full-spec dslr is bad for AP. I dont know what filter to put in to get rid of the IR star-bloat while keeping the cam more sensitive to the red glow of Ha, thats where i need your help. After doing some browsing (yeah i know i shouldve done that before modding the cam) i found this Multispectra Clip Filter and its Transmission Characteristics . Is that the filter i need? And if its more than i need, would it benefit me in any way? It would fit my D3400 and is, at least in my opinion, a steal for that price. A simple "Yes" or "No" is enough but i like detailed explanations too!
  11. Oh wow... So i was the one who got it wrong. I use that website a lot to see if a target will fit into my frame, i just cant work with the FOV calculation. I just dont know how much, lets say 2°x1.5° FOV is like i dont know how to "interpret" it, if that makes sense. Anyways i got clear skies tonigh with very nice seeing so ill see what i can get. Is the Wizard Nebula doable with an unmodified DSLR?
  12. Alright, thanks for the dark flat "tutorial" haha. Im gonna read up if APP has binning. I save some of my raw data so i can freely experiment. oh that actually makes more sense... But i remember reading somewhere that to calculate your focal length at prime focus you do: Focal length of Telescope multiplied by Crop Factor of Camera, so in my cases 1200mm x 1.5x and 660mm x 1.5x. I remember the settings in DSS for the Ring Nebula, may give it a go and see if the difference is really there or if its just my mind playing tricks on me. There was some noticeable drift but it wasnt anything extreme, maybe 1 or 2 mm on the Camera screen. I can sort that out quickly with the hand control of the scope. Thank you for the explanation!
  13. How do you actually do dark flats? from the name of it i guess its like a dark frame but the same exposure time of a flat frame? Oh so thats binning. Its like the custom rectangle in DSS, isnt it? i have never actually used that, gotta give it a try and see if it goes any smoother. Thanks!
  14. Thank you! I actually dont like it "that much", the stars are bloated and im not a fan of that. But this image brings me to my next question. I shot the Ring Nebula at 1800mm focal length (8" 1200mm dobson and 1.5x apsc crop factor dslr) and this one at 990mm focal length (102slt 660mm and 1.5x apsc crop factor dslr). There is hardly any difference in the size of the Nebula, even tho its almost 2 times the focal length on the 8" dobson.
  15. I never thought about the possibility that too few darks can add noise... I have to make sure to remember that darkframes are just as important as lightframes haha. What exactly is binning? I may be confusing it with drizzle. Also, if a gradient is barely noticable, are flats really needed? I tend to crop images more and more, except for targets that are too big for my FOV like M31.
  16. Here i am again, now with a Nexstar 102SLT on the stock AltAz goto mount. It is actually easily possible to shoot DSO's with an AltAz goto Mount, not even remotely as hard as EQ users tell you. Here are my efforts from just 1 single night, around 3 hours of being outside and aligning the mount, focusing, testing settings and searching for targets. All frames were taken 05.22,2019 night, through 05.23.2019 morning. All of the following Pictures were shot with a Nexstar 102SLT on the stock AltAz Goto Mount with a stock Nikon D3400 at prime focus, no extensions tubes, filters, coolers, heaters, field flatteners or anything else. Messier 81 and Messier 82, Bode's Galaxy and Cigar Galaxy. 49x15" ISO6400 15 darkframes Messier 57, the Ring Nebula 10x13" ISO6400 9 darkframes i forgot to defringe in Photoshop... But i got the central star in the Nebula which is a plus 😛 NGC 6992, a bit of the (Eastern?) Veil Nebula 28x13" ISO3200 (shouldve used 6400 here) 9 darkframes (this was the last DSO and the camera battery was dead) couldnt defringe because i would lose the Nebula's color. Messier 51, the Whirlpool Galaxy 28x10" ISO6400 9 darkframes every EQ user ive seen said/wrote that anything within 30° of zenith is impossible with an AltAz mount, which isnt true at all. In my location at this time of the year, Messier 51 is almost 82° high. No matter what EQ Users tell you, Astrophotography is very much possible and fun with AltAz mounts. Messier 13, the great Cluster in Hercules. i deleted the RAW files and cant remember the settings, but it was ISO1600. i cant get rid of the gradient because i didnt do any flatframes AND the Moon (can you believe how much i hate this Moon guy :P?) was 99.81%. Anyways, this was the first DSO i shot with the Nexstar 102SLT. Messier 27, the Dumbbell Nebula 18x13" ISO3200 9 darkframes Everything was processed in DeepSkyStacker, Photoshop and Lightroom. Very basic processing, Deepskystacker: Stacking ofc. Photoshop: histogram strecht, color correction, LP removal, contrast. Lightroom: noise reduction and final WB correction. I had to crop the images because they were over the maximum filesize that Stargazerslounge allows. Huge because the D3400 shoots in 6000x4000 and Deepskytacker loves huge files. I still got questions tho. If i take more lightframes and darkframes for, lets say M81 and M82, and stack upwards of 200, will the SNR improve by a lot? it seems to me that stacking 20-150 frames will reduce noise by a lot, but anything over that doesnt do anything. Is there a limit at which the SNR cant improve anymore? Criticism is very welcome!
  17. have you tried deepskystacker? what extension (Ie .NEF .CR2) do your RAW's have? DSS should not have any problems with most RAW's.
  18. Yes, the color correction in GIMP is IMO better than in Photoshop. No idea what Photoshop is doing, but GIMP doesnt remove any nebulosity at all.
  19. actually a pretty decent tutorial! I like when things are kept simple, so its easier to follow them and learn! You wrote that all your images are done AltAz, which really gives me hope todo Astrophotography with this scope https://www.astroshop.eu/telescopes/skywatcher-telescope-ac-102-500-startravel-bd-az-s-goto/p,15563 i will hopefully have the money to get it soon . Thanks for the video! One more thing... to me it seems like GIMP is almost same to Photoshop which makes it easier for me.
  20. I never really used GIMP before, only once to draw something. I will try it now and let you know!
  21. i just found this topic, and i love it already. Here are my efforts! All the images are made with an 200/1200 Skywatcher and an Unmodded Nikon D3400 at prime focus (no barlow) in a Bortle class 4-5 area. AltAz and No tracking at all. (If needed, i can give proof) Messier 27 - The Dumbell Nebula. 114 lightframes 0.5sec exposure each at ISO25600 50 darkframes 0 flatframes 0 biasframes Stacked in Deepskystacker. Histogram streching, color correction, light pollution removal in Photoshop. Final Noise reduction in Lightroom. The edits are basically the same in every single image. The grain in the images comes from the Histogram stretching.. im aware that it destroys detail, but i wanted to get as much "nebulosity" as possible. Messier 31 - The Andromeda Galaxy. 130 lightframes 0.5sec exposure each at ISO25600 36 darkframes 0 flatframes 0 biasframes Stacked in Deepskystacker. Histogram streching, color correction, light pollution removal in Photoshop. Final Noise reduction in Lightroom. Messier 42 - The Orion Nebula 399 lightframes 0.25sec exposure each at ISO25600 92 darkframes 0 flatframes 0 biasframes Stacked in Deepskystacker. Histogram streching, color correction, light pollution removal in Photoshop. Final Noise reduction in Lightroom. Some ampglow on the sides but i didnt want to crop it further. M57 - The Ring Nebula. 143 lightframes 0.5sec exposure each at ISO25600 38 darkframes 0 flatframes 0 biasframes Stacked in Deepskystacker. Histogram streching, color correction, light pollution removal in Photoshop. Final Noise reduction in Lightroom. Messier 82 - The Cigar Galaxy. (one of my favorite DSO's) 136 lightframes 0.5sec exposure each at ISO25600 46 darkframes 0 flatframes 0 biasframes Stacked in Deepskystacker. Histogram streching, color correction, light pollution removal in Photoshop. Final Noise reduction in Lightroom. So yeah, those are my efforts. I read everywhere that "Deepsky Astrophotography with a Dobsonian is impossible" and that you are only able to capture planets with it. I didnt believe that and prove myself, and maybe others, that its possible. Personally, im really happy with the images i got even if its kind of "hit n miss" and takes a long time to get the most out of your equiptment. You have maybe noticed that the colors, except for the Orion Nebula, are still way off... That is because Deepskystacker doesnt have a Debayer matrix for the Nikon D3400. I really want natural colors, but color correction in Photoshop removes too much nebulosity so im stuck with what i can do. Didnt i write "color correction in Photoshop"? Yes i did. The fake stretch image from Deepskystacker is way worse in color. I Hope you like my 5 cents and if there is anything i can improve, please let me know! P.S: If anyone wants the raw .NEF files, i can upload them for you. It will probably take 2 weeks (no joke) because my internet is bad and uploading 31.7GB with 350kb/s isnt fun.
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