TiffsAndAstro Posted Tuesday at 11:16 Author Share Posted Tuesday at 11:16 34 minutes ago, 900SL said: It ;looks about right, I use 3 minutes. It's not a lot, you are cutting out a lot of light and remember that Oiii signal is usually weaker than Ha yeah i was wondering if there is a complimentary filter something + Oiii, so that could make up some of the Oiii weaker signal on second run but need to look into that. Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 11:22 Author Share Posted Tuesday at 11:22 43 minutes ago, 900SL said: I use two zwo 2" filter holders, they slot into the filter drawer and you can buy them separately Make sure you check and get the right sizes https://www.firstlightoptics.com/zwo-accessories/zwo-spare-extra-2-filter-holder-for-m42m54eosnikon-filter-drawers.html When extracted I keep the spare one in a soft plastic wallet yeah i ordered a spare one of those from svbony with my filter for my svbony filter drawer. looks very similar, but dunno if identical. i'd like a holder to hold one or maybe two of them Link to comment Share on other sites More sharing options...
900SL Posted Tuesday at 11:52 Share Posted Tuesday at 11:52 32 minutes ago, TiffsAndAstro said: yeah i was wondering if there is a complimentary filter something + Oiii, so that could make up some of the Oiii weaker signal on second run but need to look into that. Askar do a Sii/Oiii filter but TBH I'd just pile up the Ha/Oiii on 3 min exposures. Important to get the Oiii out of the noise. You can channel split in Siril (there's a script) and use the 'linear match' tool to match the Oiii stack to Ha 1 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 12:08 Author Share Posted Tuesday at 12:08 3 hours ago, iantaylor2uk said: I tend to use 2-3 minutes subs when using my L-Enhance filter (as opposed to 30-60 secs for simple IR/UV filter). I would also look at increasing your gain value since you're less likely to saturate stars, and you get lower noise at higher gain Apologies if this is repeat post, I thought I'd replied I'm going to stick with unity gain = 101 to start with, and will up my exposure times if needed. but with clouds and satellites and such, I think 5 and 10 minutes sub times are out, so might need to up gain if 3 min subs seem under exposed. does that seem like a decent plan? Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 12:11 Author Share Posted Tuesday at 12:11 17 minutes ago, 900SL said: Askar do a Sii/Oiii filter but TBH I'd just pile up the Ha/Oiii on 3 min exposures. Important to get the Oiii out of the noise. You can channel split in Siril (there's a script) and use the 'linear match' tool to match the Oiii stack to Ha Er not seen the linear match tool. All I've done in my experiments with fake hoo was ha to red channel and Oiii in green and blue channels. Doesn't look great but then it wasn't real ha oiii. Need to look at linear match in siril. It sounds like what the normalisation feature in pixinsight does? Link to comment Share on other sites More sharing options...
900SL Posted Tuesday at 12:20 Share Posted Tuesday at 12:20 (edited) 8 minutes ago, TiffsAndAstro said: Er not seen the linear match tool. All I've done in my experiments with fake hoo was ha to red channel and Oiii in green and blue channels. Doesn't look great but then it wasn't real ha oiii. Need to look at linear match in siril. It sounds like what the normalisation feature in pixinsight does? Yes, it's a while since I did dual narrowband but from memory: Use the 'OSC extract Ha/Oiii' script to create two (mono I think) files for Ha and Oiii from the dual narrowband stack Do background extraction both files Do star extraction if required on both files separately on the linear file (I think.. ) Do linear match on Oiii file using the Ha file as the reference. This matches the background ADU of both files Not sure what I did next, maybe process each file first , then Pixel math or RGB composition to combine both files into an RGB image There's guidance on line Edited Tuesday at 12:21 by 900SL Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 12:51 Author Share Posted Tuesday at 12:51 (edited) 31 minutes ago, 900SL said: Yes, it's a while since I did dual narrowband but from memory: Use the 'OSC extract Ha/Oiii' script to create two (mono I think) files for Ha and Oiii from the dual narrowband stack Do background extraction both files Do star extraction if required on both files separately on the linear file (I think.. ) Do linear match on Oiii file using the Ha file as the reference. This matches the background ADU of both files Not sure what I did next, maybe process each file first , then Pixel math or RGB composition to combine both files into an RGB image There's guidance on line cheers for all that. all i've seen so far is in the siril guide and its not much, but im sure i'll find more if i need any after your tutorial i've already saved your tutorial to a text file for handy reference. im fairly sure this is a tool i that was only in pixinsight so im very happy to find siril has it Edited Tuesday at 12:52 by TiffsAndAstro Link to comment Share on other sites More sharing options...
Elp Posted Tuesday at 13:12 Share Posted Tuesday at 13:12 You could just extract the red, green and blue channels separately in gimp or PS. Simple. 1 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 13:53 Author Share Posted Tuesday at 13:53 40 minutes ago, Elp said: You could just extract the red, green and blue channels separately in gimp or PS. Simple. Siril also does this, but on a stacked result only. Link to comment Share on other sites More sharing options...
Elp Posted Tuesday at 13:55 Share Posted Tuesday at 13:55 But that's what you want, you extract/split the channels after stacking. 2 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 14:22 Author Share Posted Tuesday at 14:22 24 minutes ago, Elp said: But that's what you want, you extract/split the channels after stacking. Sure but I have the other siril stacking option to stack into separate Ha and Oiii results. I literally have no idea the pros and cons of each, other than one is via a stacking script and other works on final stacked results. I'm sure I'll try both 1 Link to comment Share on other sites More sharing options...
Elp Posted Tuesday at 14:29 Share Posted Tuesday at 14:29 Up to you how you go about it. When doing OSC I usually just process the stack as is (with starless of course), don't split channels or anything. Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 14:32 Author Share Posted Tuesday at 14:32 (edited) 3 minutes ago, Elp said: Up to you how you go about it. When doing OSC I usually just process the stack as is (with starless of course), don't split channels or anything. Pretty certain this will be my first option, but no harm me having other options to compare results to hopefully my 1970s orange brown colour scheme will be a thing of the past Edited Tuesday at 14:33 by TiffsAndAstro 1 Link to comment Share on other sites More sharing options...
Elp Posted Tuesday at 14:42 Share Posted Tuesday at 14:42 The main thing will be incorrect star colour but you already know to image separately and replace these after. 1 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Tuesday at 14:51 Author Share Posted Tuesday at 14:51 7 minutes ago, Elp said: The main thing will be incorrect star colour but you already know to image separately and replace these after. Yeah been testing that. How much I need time I need to grab RGB stars I'll find out. Starting at 30 minutes I think Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Wednesday at 21:19 Author Share Posted Wednesday at 21:19 (edited) I'm on M16 right now. Had to polar align a little later and with 7 sec subs. But it was still daylight my first 2 mins sub looks good gonna look at stats 100 ish x 1 min which is pretty good i think the flag im shooting through/past is making my guiding a bit [removed word]. once i lose m16 for the night in about 30 mins ill try ngc6888 crescent nebula can compare it my broadband version... ....which is what a sensible person might say. I'm tempted to go squid hunting. Edited Wednesday at 21:28 by TiffsAndAstro Link to comment Share on other sites More sharing options...
Stuart1971 Posted Wednesday at 21:33 Share Posted Wednesday at 21:33 On 26/08/2024 at 20:07, TiffsAndAstro said: Sadly siril only has a split Ha/Oiii script. I'll look see if anyone wrote one I could use or maybe edit the values to work on different frequencies. Lots of options on pallettes. I meant do I need filter specific darks and biases? Do you use different dark and bias library sets for each filter? Thanks for the help No, as they are darks, so they don’t care what the filter is as they can’t see it….👍🏻 1 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Wednesday at 21:51 Author Share Posted Wednesday at 21:51 17 minutes ago, Stuart1971 said: No, as they are darks, so they don’t care what the filter is as they can’t see it….👍🏻 was just double checking ty Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Wednesday at 22:06 Author Share Posted Wednesday at 22:06 (edited) for 2 mins, looks ok. guiding is a bit iffy hoping its how low it is in the sky. im zoomed in a bit in nina. also no clipped pixels dark or bright. which i think is ideal? Edited Wednesday at 22:08 by TiffsAndAstro Link to comment Share on other sites More sharing options...
WolfieGlos Posted Wednesday at 23:21 Share Posted Wednesday at 23:21 (edited) Looks good to me 👍 Yes, guiding will be worse the closer you get to the horizon. My guiding was 2” and higher if I recall on M20 a few months ago. Subs were still fine though. Im currently aimed up in Cepheus so near the zenith - guiding has been 0.5” ALL night. I’ve never had that before! Just a shame I’ve just lost 20 minutes of subs since the scope dewed up 🤦♂️ Caught me totally by surprise, so watch out. Edited Wednesday at 23:21 by WolfieGlos 1 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Wednesday at 23:29 Author Share Posted Wednesday at 23:29 6 minutes ago, WolfieGlos said: Looks good to me 👍 Yes, guiding will be worse the closer you get to the horizon. My guiding was 2” and higher if I recall on M20 a few months ago. Subs were still fine though. Im currently aimed up in Cepheus so near the zenith - guiding has been 0.5” ALL night. I’ve never had that before! Just a shame I’ve just lost 20 minutes of subs since the scope dewed up 🤦♂️ Caught me totally by surprise, so watch out. I took a 10 minutes test on squid and saw no squid. So I went to the safer plan. 1 Link to comment Share on other sites More sharing options...
WolfieGlos Posted Wednesday at 23:47 Share Posted Wednesday at 23:47 14 minutes ago, TiffsAndAstro said: I took a 10 minutes test on squid and saw no squid. So I went to the safer plan. Good call. I might give it a go with my SY135 one day, but that’s only because it’s f2. 1 Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Thursday at 00:58 Author Share Posted Thursday at 00:58 Er clouds so doing flats Is 9 seconds unusually long? Link to comment Share on other sites More sharing options...
TiffsAndAstro Posted Thursday at 01:00 Author Share Posted Thursday at 01:00 1 hour ago, WolfieGlos said: Good call. I might give it a go with my SY135 one day, but that’s only because it’s f2. It's a great area for stuff. Link to comment Share on other sites More sharing options...
Stuart1971 Posted Thursday at 07:18 Share Posted Thursday at 07:18 6 hours ago, TiffsAndAstro said: Er clouds so doing flats Is 9 seconds unusually long? I do all my flats at 4 seconds, 9 seconds seems a bit long, but if they are good then try them..👍🏻 1 Link to comment Share on other sites More sharing options...
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