Orion Nebula (M42) with a DSLR, Start to Finish, Pt. 2a - PixInsight

I have version 1.8 Ripley I think that's the newest version it'll let you know about updates new version of pix insight released one point eight point six I haven't gotten it yet so oh maybe I have I'm not sure what that meant but usually it just gives you a little thing about updates and then if you want them you can check them and say you know update after I finished working on this okay let's go ahead and look at what we have so in the pics insight there's a really handy tool called blink it's under processes all processes then this is just an alphabetical order and I'm going to choose blink and I'm gonna open up my folder of lights and click and shift-click to select them all it's going to load all of those files up for me here and a list over here in the blink window all right so here we go all the files are loaded here in blink and what I can do now is I can just quickly step through them by hitting the down arrow or just clicking on one and this is helpful for a few reasons one we can sort of evaluate the sky brightness as the night passes because it applied an auto stretch to the first frame here and then if we can see down here we can see the sky got a lot darker so when that happens you might want to wait the files that have the darker sky higher than the files that have the brighter sky and there's different ways we can do that especially if we use the process called subframe selector I'm probably going to do that in this video just because it'll take too long to explain everything but the main thing we want to do in blink is just evaluate the frames for focus and for tracking issues especially with light weight mounts like I was using there might be some tracking issues here these all look pretty good sometimes it's hard to see exactly what's going on until you zoom in stars look pretty good there and you can basically just quickly click through these and just take a look at the stars like in that one they look a little bit more streaked and actually in those two right there and let's say you wanted to then reject those frames you can just say let's move those selected files to a new location with this little button down here and you could just make a new folder that's like rejected frames something like that I'm gonna keep those in they didn't look too bad let me go all the way down here to the bottom and make sure my focus is still okay focus looks good here okay but on this final one ice clearly see there's a problem so see eight three five one looks okay but when I go down to eight three five two there's this little artifact on all the stars zoom in even more so you can see what I'm talking about here come on there we go so you see how there's that little line coming out of all of the stars that's usually an indication to me of probably I hit the Mount somehow by stepping too hard near it or actually manually running and do it or something and so I would not want to use this frame in my final stack because it might mess things up so I would then just not use this final one when I'm stacking these but most of the rest of these look pretty good so I'm probably gonna use all these but you really do want to blink through your frames make sure that there's no big surprises if in one you notice there was maybe like a satellite trail or a airplane trail that probably would be fine because through the stacking algorithm it will automatically reject those pixels if it only shows up in one or two frames so let's go ahead and close out a blink go up here to no over here on the left-hand side to format Explorer go into DSLR RAW format Explorer and click Edit preferences and what I like to do before I do any calibration is just set this to pure raw so you just click on peer raw right down there it turns off any image flipping it doesn't try to debayer before calibration at deep layers after calibration that's what this create raw CFA image means and you go ahead and click OK to accept that and now normally what I would do is I would go through the processes of subframe selector image calibration image registration image integration all these different processes separately to make my fully calibrated stacked image because I like to sort of do it all manually to see what's going on as I go but because this is a beginner video and I don't want to make it too long I'm gonna use a script and a lot of times the scripts take a bunch of complicated processes and picks inside and combine them together to make the whole thing easier so I'm gonna go to script batch pre-processing and choose batch pre-processing and this is very similar to like deep-sky stacker you just load in your lights or flats your darks your bias and it basically takes care of the rest for you but just like with deep-sky stacker if you want to you can go in here and go into more advanced topics so I'm gonna go ahead and add my lights here just select all of those except for the last one because we didn't want that last one 8 3 5 2 click open all set select my flats I'll select my darks I'm just clicking these little add lights add flats add darks buttons at the bottom and add my bias or offset okay we have all those loaded now I'm not going to generate drizzle data even though normally I might because I don't want to get into that right now let's check our integration parameters here so percentile clipping that is not the one we want basically it gives you an idea of the best rejection algorithm by just hovering over it right here and there's different options based on the number of frames you've captured and for over 25 frames or something like that I think linear fit clipping is the best so I'm going to choose that you might want to change some of these parameters depending on what you see in the final stack but a lot of times you don't know until you do it so I just leave those on the default for now everything else here looks good over here we want to tell it that these are CFA images that means color filter array such as a Bayer pattern which is on all DSLRs so I want that on Bayer mosaic pattern you can leave that on auto but the most common one is our G G B and V and G for the debayer method is fine this probably doesn't matter if it's checked off or on but we're not using fits file so I'm going to go ahead and uncheck that okay and now we have to pick a reference image for our registration and I remember the first one looked pretty good so I'm gonna choose lights and pick that first image basically that's the one it's gonna look to for registering all the other pictures against the star pattern if we did subframe selector we could mathematically know which was the best one in terms of focus but since we didn't I'm just going to use the first image I shot because that's right after I focused meaning the stars should be in good focus there and then I'm gonna choose an output directory here I'm just gonna make a new directory called pix insight process okay this all looks good I'm gonna go ahead and click run it'll give me some warning about you know you might you might want to integrate the lights yourself using image integration process that's fine we'll go ahead and click continue and then just let it roll and this takes a while we're just going to let it do its thing and come back in a few minutes here all right once that's over we can click exit there and say we want to exit that then you get a file open go into this process folder find master if you want to look at any of these if you notice any problems you can but me the main one we're interested in here is the light master so light binning one dot X is f I'm going to go ahead and click on open brings this up this is in a linear state so if I click on this little STF auto stretch button over here we can sort of see what we have and you'll notice the background here is very red that's normal that's the the light pollution and basically just the channels being a little bit out of sync here if we click on the actual screen transfer function process and we link the RGB channels I'm still red ok nevermind ok but the next thing we want to do here is we want to go ahead and extract the background here so we're going to go to processed background model ization and usually I just start with the automatic and see how well a job that does and so we're going to subtract the background and go ahead and just apply that okay so here's what the background looks like basically pure red and here is our image without that red background now it's a good starting point but it did some strange things here I think it over corrected the middle seems darker here and then there's like a ring around that which is a classic thing with automatic background extractor so I'm gonna go ahead and move that over to the side here and try my own hand at this just using this is a reference so I don't accidentally put a point on any nebulosity but I'm gonna use dynamic background extraction so I'm gonna go to process background model ization dynamic background extraction go ahead and click on this to tell it that this is the active window here then I'll just go ahead and use these default parameters and see how it does I'm gonna go down to sample generation and click generate okay so with the default it didn't place too many samples and it placed one right in the nebula so a little bit off there so let's go ahead and play around with these model parameters a little bit I'm gonna increase the tolerance to one I'm gonna increase the smoothing pact factor to 0.5 and down here under minimum sample weight I'm going to decrease that to 0.5 and click generate again okay so that gave me a bunch more samples but it's still not having samples down here at the bottom so I'm gonna increase the tolerance just a little bit more 1.3 let's say and generate again well we still don't have any samples down there at the bottom but that might be fine we could just crop that bottom part away if it's too hard to model that part the other thing I'm going to do here though is I'm going to look at where there is no Buhl ASSA tea here my automatic automatically subtracted one and I'm gonna get rid of any samples that are in that nebula part so I'm gonna move this one out of the way that one looks fine this one is probably a little too close I'm going to move that out of the way this one is definitely in the dust there so I'm going to move that over there okay the other important part to do with dynamic background extraction is starting with this sample up here in the top left I'm gonna step through each sample looking at this screen right here on the dynamic background extraction panel and just make sure that I don't have anything like this where it's the big star is basically taking up the whole sample like that because that will throw off the model then I might manually place a few samples down here and the lower part as well okay yeah I'll go back up here to the top oops click on this one try to there we go step through there's another one that's on a big star so I'm just gonna move that a little bit over you can see I'm doing this pretty quick just looking for if any are hitting well on this one you know has two stars right there in the field so I might just move that off to the side a little bit I basically just want these samples to be modeling the background and not stars or nebula features okay looks good I'm just going to put one down here in this corner you can add as many manually as you want but you don't have to add too many or it it sort of throws off the models usually simpler is a little bit better okay I'm gonna go ahead and choose subtract here and apply all right if I look at the background looks like that look at this you can see I'll just get rid of this I'll minimize this if I compare that to automatic you can see the automatic sort of created this weird ring effect well by a dynamic background extraction looks a lot better in that regard there's no ring effect it looks pretty good out here towards the edges there's still some artifacting and noise and things but we can just go ahead and crop that away right now let me go ahead and get rid of this a B E I'm gonna go ahead and go up here to process geometry dynamic crop click on it then reset it and then just drag in from the sides here to get rid of all this sort of noise on the edges and apply and that's looking quite a bit better the background is still a little bit blotchy but this is super stretched so most of that is just noise that we can that's going to actually disappear once we do the real processing okay next thing we can do here is I'm gonna go ahead and save this I'll just call it put it in my process folder here and I'll call it integration DBE drop alright now what I'm gonna do is I'm gonna extract a luminance which you can click on this little button right up here it says extract CIE L asterisk component but that may basically means extract illuminance and I'm going to open up screen transfer function and histogram transformation I'm going to apply the screen transfer function drag that down here by the little triangle and apply it on the histogram reset the screen transfer function and now I have a stretched luminance right there I'm gonna reset my histogram transformation here and with this luminance in the view and basically just continue to stretch that a little bit so that this histogram peak is right at about mid like that and this is basically just what we're gonna use to put on as a mask when we apply some noise reduction I like using a nice highly stretched mask like this to make sure that I'm not going to accidentally overly smooth any of these nebula features this is actually maybe even a not quite aggressive enough so sometimes I'll also open up curves here and just open up a preview and just really try to make sure that all the nebulosity part is gonna be protected against this that looks good okay so I'm going to go ahead and apply this and invert it mask invert mask and now I have a nice mask that's protecting the red is the part that protects and letting in a little bit of noise reduction which we're going to apply next on to the sky so I'm going to go to process multi scale median transform I'm going to increase the number of layers to six turn on noise reduction on all of them and basically with the smaller scale structures we want to apply more noise reduction so you increase the threshold well do I don't know ten or something like that on that first one and you just sort of decrease it on each one so I'm going to do nine seven five three two and one something like that and just go ahead and apply that on this masked version here this is my favorite noise reduction thing to do while the data is still in this linear format like this and basically this is just like a blurring kind of noise reduction it takes a very crunchy noisy looking stuff and blurs the pixels together a little bit I guess they call it smoothing but it's basically blurring and the multiscale part is that it it blurs on different scales and you can set different amounts of blurring based on the scale of the structure so what I'm doing here is the very small structures are getting more blurred together while the bigger structure is less blurred together okay I'm gonna go ahead and remove that mask and you can see that it made the sky a little prettier a little bit more smooth looking and so the next thing we want to do is apply some color calibration to this so I'm gonna go to process color calibration photometric color calibration we can search coordinates and just type in m40 to search it finds it you say get and it puts in the right Ascension and declination for you for focal length it was 360 and pixel size so 3.7 to 360 focal length knows the RA and Dec good good good for white reference I almost always use g2v star and I'll go ahead and apply that basically what this does is it plate solves the image it then pulls up catalog data and linear fits and changes the colors in RG and B so that the as many stars match the catalog data as possible in the field and then it gives you a nice plot showing you know how many of your stars agree with the found stars and so here it's telling me that it found 319 reference stars of those 25 have problems but that means it still has almost 300 stars to try to match the color against and it's gonna take all my colors and match those against those catalog stars so very nice little color calibration tool built into pix inside here it's fairly new I think like year and a half to two years old maybe and it works really well for me some people have had trouble with it but I've always found it to work really well okay so here's our white balance function plots you can see for the most part the Stars match up against this slope and then there's a few outliers but that's okay now it looks really weird right there but that's because we just have to reset the auto stretch so I just turn it off and turn it back on and for the most part you're probably not going to be see much difference there but once we fully process it it should really help with getting accurate color alright so we've done that one more thing I like to do here on DSLR images like this is to neutralize the background which the way we do that is we make a sample here of just the background with no stars in it just through a preview you just click on a little preview button you drag out a preview and then you go to color calibration background neutralization you set the reference image to your preview and you apply background neutralization again doesn't seem to make much of a difference but it helps later on and then I can just kill that preview reset my auto stretch there we go all right next up what I'm gonna do is I'm going to apply one little thing more of noise reduction which is SCN are green because I see some green noise here in the image I usually don't set this to the full amount I do something like 60 or 70 and you just apply it and it takes out some of the green and green noise in the image all right now we can go ahead and apply stretching we could try math stretch which is an easy way to do this you basically just tell it what is the background and then it stretches it for you but I'm gonna do stretching by hand because I just like doing it by hand so I'm gonna open up histogram transformation here reset it open up this one DBE and then I'm just going to take this middle slider and move it over here until I can see the little histogram peak come up over a little bit apply it and you can see that applied an initial stretch and I'm going to just do that again and now I'm gonna really back off and reset the black level here and that might be good enough for now actually be interested to compare that to a mass stretch let's just see what the two the difference is here so I'm gonna undo what I just did let's go ahead and make a copy of this just by dragging it out by the little tab over here on the left hand side I'm gonna rename this one mass stretch and I'll rename this one HT for histogram transformation okay and on this one I'm going to do the same thing I'm going to stretch it back out again okay so that was my histogram stretched image like how it looks the most part and then here's my masse stretch so with mass stretch you're just going to first define a preview of the background I'm going to use this little area right here again then you can turn back off the auto stretch go up to process intensity transformations math stretch for the background reference choose that preview and then apply it and it basically is doing the same kind of thing I was doing in histogram transformation but instead of just applying those stretches those stretches did the same image it first masts off the background and so it's just stretching based on what is not background and then it also does it in something like a hundred iterations well yeah he was set to a hundred iterations while you can see a histogram transformation I did it in about four iterations so sometimes it looks better sometimes it gives the image a funky look but while we're in this state of getting ready to stretch the image let's just try both and see which looks better okay it's done you can go ahead and drop the preview here and compare these two honestly they're pretty similar the mass stretch just brought up the background level a little bit beyond what is called for for this image so but it maybe also retained the star color a little bit better so if I can't decide between these two I might just combine them with pixel math so I can show that I'll just do process pixel math and I'm going to do the expression editor here do point five times HT plus 0.5 times math stretch all right and I want to make a new image so under destination I'll say create new image whoops click the plus I mean the square to apply that okay and then I get somewhere in between those two which I actually think looks the best of those three so cool I can save this off press command S save this off as after stretch and I think I want to try to remove some of that vertical noise banding I'm seeing there's a script for that under utilities canon bandung reduction there that did it so I applied it to aggressively the first time because I didn't know what I was doing I guess but with a less aggressive mode it worked pretty well for removing that banding that I was seeing what else is left to do we could try making a range selection so I'm going to do mass generation and range selection open up the preview here increase the lower limit until it's basically just selecting the nebula and the stars make it a little bit fuzzier a little bit smoother something like that and then it comes out like this that's taking up too much sky so I'm going to open up my histogram transformation and basically darken out the sky there okay so I'll go ahead and apply this mask and so now it's just it's just selecting the nebula and the bright stars and I'll go ahead and uncheck show masks so I can see what I'm doing I'm going to open up a curves transformation and just apply a bit of saturation to all that and so you can see let me reset it that's without if I just sort of move up this saturation curve a little bit it adds more saturation to the object I'll go ahead and apply it this is showing me if I now applied it again but that looks like too much to me so I'm gonna tamp it down a little bit here apply it again cool and then I'm gonna go ahead and reverse the mask by clicking invert mask and move this saturation slider in the other direction to desaturate the sky just a tad alright and actually let me open up that one more time I'm also just gonna bring the reset this go to RGB k mode and I'm just gonna bring the intensity of the sky down just a tad to the brightness of the sky basically don't want to clip it to you know really black like that you want to leave in a little bit but this is where it was that's sort of a dull gray I just like to make my sky a little bit darker than that something like that yeah messed it up try again grab it right about there just bring it down just a tad okay I basically like it like this I'm just gonna go ahead and save that off as after stretch and curves but if you wanted to try to define the nebula features a little bit more we could reverse that mask one more time and we also would want to get rid of all the stars actually let's just make a new mask this okay so we could instead of doing a mask that includes the stars like that which we were using for saturating to go back to range selection open it up again and increase that smoothness slider until all the stars are out of it and it's just got the the nebula part here okay and then I'll apply that just to show you which part of the image it's working on here just there and what we could do with this applied is go into intensity transformations local histogram Equalization and what this does is it works it does a histogram feature but just on the part we have masked and it's sort of like a extra bit of contrast it really sort of it's similar to like the clarity slider in Photoshop it just adds a bit of sharpness and contrast at a local level and this kernel radius is saying which scale you're working on so smaller scales it's gonna be a smaller kernel radius bigger scales a bigger kernel radius and then the contrast limit is what difference in contrast between two pixels do you want it to pick up on so a contrast limit of 1 is not going to do much at all two is going to be a lot is twice as aggressive so 1.5 is usually where I start and then the amount is how much of it you're applying this is a good one to make a preview over the part of the image that you're working on and then just bring up that preview in here and so you can see by changing the kernel radius it changes the fineness of the detail that it's working on so for this image I think something like 140 looks pretty good I'm gonna bring down the amount a little bit 0.75 all right go ahead and apply it okay close out of that out of that drop the preview and I can just click undo and redo to see what it did helps if you're really far zoomed in here okay so just look at this detail right here if I redo that's with the Histadrut local histogram Equalization that's without it so you can see how it just made the darker parts a little bit darker adds that local bit of contrast there's another way to increase dark structures in your image which is a script over here script utilities dark structure enhance so if you're interested in this you can just try it out it uses a masked approach and sharpens with multiscale transforms and things like that and I picked some pixel math expression it looks like see what it does here again these scripts are often using processes and just creative ways so you can pay attention to what they do here and try to recreate it yourself oh whoops you can't apply that to a masked image let me remove the mask try it again duh the reason you can't apply it that script to a masked image is because it uses masks and so it gets confused if you if you try to apply it to an image that's already been masked because it already creates the masks for you is the idea ok that's done so I can hit undo redo and the main area where I see that did something is look right here under m-43 before and after so basically just figured out where those a little Dark Nebula were and made them darker which it's nice it adds a little bit of contrast to the image in a cool way ok so I'm pretty happy with this there's definitely a lot more I could do with it here in pix insight but I'm gonna say that this is done so I'm going to save it one more time call it first try P I and then I'll also save it off as a PNG file and it'll give me this warning about your losing numerical accuracy by making it into an 8-bit file but that's fine okay all done with processing our m42 here in picks insight if you have any suggestions for future videos or other things you'd like to see either with processing or acquisition or gear or anything just let me know in the comments and I'll try to address those thanks so much for watching you

Channel: Nebula Photos

Views: 11,538

Keywords: pixinsight, m42, orion nebula, orion, astrophotography, astronomy, processing, canon, dslr, photometriccolorcalibration, rangeselection, histogramtransformation, maskedstretch, at60ed, astrotech, ioptron, smarteq pro, calibration, nico carver, nebula, nebulaphotos.com, nebula photos

Id: RGf5zTUC2MQ

Length: 46min 42sec (2802 seconds)

Published: Fri Dec 28 2018