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Showing results for tags 'stacking'.
Found 26 results
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I like live stacking as I can see the image develop and it saved my hard drive being cluttered up with thousands of images. The downside, I have found is that if a cheeky wisp of cloud comes over, it often gets included (in spite of trying to clamp down the FWHM settings). Some of my images then have a like a grey smear over them. Then after and hour of live stacking I find it looks just like a greasy smear over the picture- which is a real pain to try and post process out. Always seems to happen when I pop indoors to make a drink etc. I noticed that there was a setting on SharpCap. to save the stack- save and reset. Which I have not used yet. So Im thinking maybe I should do shorter live stacks eg. 30s for 5-10 minutes and then stack the results in A!S or DSS, so I can weed out the poorest sets, and I least I get something. Gives me a chance to do any slight re-adjustment too. Is a stack of stacks the same as doing a longer stack? My rusty school maths says it should be - but thought I'd see if anyone else does this. (I guess the setting wouldn't be there otherwise) Thanks -
Hi is anyone using Regim to stack using a dslr modded , currently trying to work out the settings in regim , im using a modified canon 1000D , do i need to set up libraw within regim ? if anyone has good success in using regim i would be interested in hearing what settings you are using .
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This is probably silly, but anyway here it goes.... What would happen if say someone intended to shoot 100 of 60sec subs of orion nebula or Andromeda, and clouds rolled in the middle of the session or just got bored and stopped for a hot beverage. Now this poor fellow is left with only 50 subs and starts thinking of copying and renaming these 50 subs in the same folder (unaltered or with slight denoise or slight Gaussian blur) and stacking all of the 100 subs?
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Hi, Hoping for some help here.. Im trying to learn some basic processing in PixInsight, including the PreProcessing (calibration, registrering, stacking, etc.) Im using the only data I have, from my very first lights of M13, calibrated with a SUPER BIAS, no darks and flats yet. When doing it in DSS I get 7 images stacked and the stacked file looks OK. Switching to PixInsight it goes horribly wrong after stacking, and the stacked picture looks like the attached. I have done the whole process in two different ways, but get the same basic result. 1. Doing all the steps manually: Calibration, Debayering, SubFrameSelection, StarAlignment, Stacking. 2. Doing everyting with the BatchPreprocessing script I yield the same result, its like the subs aren't properly aligned, even though the process has eliminated A LOT of bad frames (from 26 to 5). Link to zip with the 5 registered light: https://www.dropbox.com/s/sj2ytaa00u5qlap/GREAT CLUSTER_LIGHT_45s_400iso.zip?dl=0 Hope someone can give me some pointers, none of the tutorials I have been following explains why this can happen. Thanks in advance stargazers! -
Yeah, back again (sorry). But having sorted out my problems with my star halos caused by the settings in DSS, I have now had a go at combining two images to keep the core from burning out. Not going to win any awards but I am quite happy with it as my "first" proper Orion shot. I'm proud enough of it I sent a copy to my mum! Essentially: 27 of 29 60s ISO1600 shots stacked for the Nebula 30 of 30 20s ISO400 shots stacked for the Core Stacked in DSS with minimum processing to match the output TIF files. TIF Files opened as layers in GIMP, aligned and a layer mask attached to the top Nebula Layer. Used the paintbrush to blend the two layers and saved as one after a bit more processing in GIMP. I think the ISO1600 shots over-cooked it a bit, so there is some noise in the darker areas, but I'll just go back to ISO800 for the next ones. First image shows the output from the Nebula stack, complete with burnt out core And then the second image after blending the core As I said, it won't win any awards, but I am happy that I am making some progress. Next to try and eke out a little more for the subs and try and get them up to 90s and will keep trying to get more detail out of the images. So to everyone starting out like me.....keep at it, it is amazing how quickly you can progress in your knowledge of this astrophotography lark, so don't give up. Obviously the more you learn and the better you get, the more it is going to cost you, but the nights of banging your head against a brick wall of clouds, rain, bad subs, poor processing and general frustration are worth it when you finally get a picture that you like. And thank you for everyone for humouring and helping me this far. I'm bound to be back again and again for more questions but, hopefully, I'll be able to start helping others as well! Clear Skies!
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Hi there, I am still new to amateur astronomy and astrophotography. I recently took my first steps towards moon and Jupiter photography. While I am satisfied with my moon pictures, I am struggling with Jupiter. I am a bit desperate, so I hope that maybe someone good give me a couple of useful hints so I can learn and improve. When shooting Jupiter without any barlow lense or eyepiece, I manage to get a sharp picture and am actually reasonably satisfied with the results (see attachments named "ok.."). I use Firecapture to shoot something like 3000 single images (mostly JPEG because I had issues with other formats.. maybe this is one of my first mistakes) and stack them afterwards. When recording AVI movies with Firecapture and dissecting them to single pictures afterwards, my results are less sharp than taking photos, so I sticked to recording images instead of movies. When the image is stacked, I continue with editing using Registax. After tweaking around, I obtain a sharp image of Jupiter as a result. Now to my issue: I want to obtain bigger images from planets, especially Jupiter, and therefore bought a premium 3x barlow lense. I tested it on the moon and was very satisifed when comparing the view (and images) to my cheap 2x barlow lense. So I think I managed to see the difference and I think that the new barlow lense does quite well. When putting the ASI ZWO cam into the barlow lense and shooting Jupiter, the effects of the seeing increases (as I expected) and the image starts getting more noisy, but the single frames I see within Firecapture are still ok (at least that is what I think, maybe I am wrong there). I play around with the values for gain and shutter speed, select the Jupiter profile and start shooting (max. 180s because of Jupiter's rotation, I receive around 20 - 50 FPS, depends on the shutter speed, ofc). After 3 minutes, I receive between 2000 and 4500 single JPEGs, depending on my settings. Of course I know BMP or TIFF should be better, however I often have issues with Firecatpure's BMPs/TIFFs when putting them into pre-processing software such as Pipp. I pre-process, stack and edit my images and then still have a blurry Jupiter in front of me (see attachment, images named "stack.."). No matter what I do and how I tune the settings within Registax, Jupiter won't become any sharper when using the stacks which were recorded through my 3 x barlow lense. Could this be because of my recordings (bad image format, not enough frames..)? Do I need more frames when recording through a barlow lense? Or can't I do any better under the conditions of my site (see below)? Are there any tricks when recording through a barlow, do I need other settings or shall I use another software? I attached the stacked image ("stack6_raw.tif") and am curious if someone could get more out of it. For me, this tif looks like the stacked pictures of the small Jupiter pictures, and I managed to get them sharper. So I wonder if it's me or if I simply can't expect more when using a barlow lense? If so, how can I shoot bigger and sharper pictures of Jupiter then (without having to switch my telescope, I know that my Newton is not the "planet killer"). I am greatful for all hints! My equipment and software I use: EQ6-R Pro with GoTo 8" inch Newton (200PDS 200mm 1000mm f/5) 3x Premium Barlow ASI ZWO 290 Color and cooled Recording: Firecapture Preprocessing: Pipp (Planetary, output in TIF) Stacking: Autostackert 3 Editin: Registax6 My site: Germany Small town, lots of light pollution, but it's still "ok" Mid - strong seeing on most days stack6_raw.tif single_stack6.tif single_small_jupiter.tif -
Hi everyone, the black and white image is an image that I stacked in dss and the other image is a single shot of what I stacked! I was wondering if anyone would take a crack at editing the stacked version of the picture for me as I am trying to get my head around editing and am wondering what a picture like this could look like with a bit of tweaking ? Thanks everyone
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Hi all - I've been using our family Canon 350d for long (60 second) exposures over the last week to see what I can get. Stacking is the next thing to try out - I have a ToUCam Pro II but no adaptor yet. I've looked up in Stellarium and Jupiter rises over my location around 4am, so I was thinking of giving that a go. From what I understand you have about 3 minutes to get as many shots as possible before Jupiters high turn rate starts to affect the shots. With that in mind, and I think the shutter speed has to be about 1/125th ish otherwise the light from Jupiter will wash out the bands, colours etc. But will I physically be able to fire off enough shots to count? The 350d doesn't a) have Live view and can't take avi files. So it'll need to be manual firing from the cable release. So do I try or wait until I get the webcam adaptor? cheers frank -
I understand the purpose of shooting dark frames, but what are 'flats' used for? Is there a general ratio of darks and/or flats to process with the collection of images when you stack them?
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Ok, so i had my first run at planetary imaging yesterday evening, which was disappointing to say the least :/ I was trying mars. The setup went smooth, and imaging went ok as well, but the seeing was very bad and especially the heat of the atmosphere was high, which blurred the images to the point that mars' image was not even a sphere (see left image). There are , however, also other probable issues: + Short focal length (800mm) with an 8mm EP, resulting in only medium magnification + problems with focusing the blurred image + missing real astro darkness (24th of june) + days' high was around 28 deg c, although it had cooled down to 22c at imaging time... Have you guys & girls tips on how to improve? The resulting image from stacking 1600 out of 3800 images was a mess, but at least spherical
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Now that imaging season has come to an end, I have the time to do some reprocessing of old data, and I thought I'd share some of my processing methods. I gathered much of that data before I started doing dithering, and the usual background I am fighting looks like this: This is an extreme crop of a wide field image of the area around NGC 1499 (the whole frame covers the area from M45 to Mirfak), taken with my unmodified DSLR. The stars show trailing, but this is not a problem in the final image. Process details: 12 subs, integrated using AVERAGE integration with sigma clipping; no other method for hot pixel removal was used. As you can see, despite pixel rejection during stacking, there is a streaking pattern. This is due to hot pixels which weren't removed during the calibration/stacking process. In my case, it never made a difference if I used darks or not, some of this pattern always remained. The next image shows the stacking result for the same subs, but this time with MEDIAN integration with aggressive percentile clipping (20 % high values) and hot pixel removal during calibration (cosmetic correction using the Auto Detect option in PixInsight): As you can see, the streaks are gone, and it will be much easier to process this image further. Since I can't control my cameras temperature, and it's difficult to match dark frames to light frames, I don't take dark frames anymore. Instead I rely on bias frames and cosmetic correction to remove read noise patterns and hot pixels. During this past season, I started using dithering, and found this to be the best way to remove stacking artefacts and large scale noise (what Tony Hallas calls "mottle"). I typically dither 15 pixels between frames in a spiraling pattern. After star alignment, the dithering pattern looks like this: M45_dithered.mp4 This is a crop of debayerd and aligned raw files. No calibration process or cosmetic correction was used. As you can see, the stars are aligned, but the hot pixels move around and will be effectively removed during image integration. If these were calibrated files, I would also have used cosmetic correction, and the number of hot pixels would have been much lower. I hope this information can be of use to anyone fighting the same problems. Cheers,
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I'm very new and green when it comes to image processing/photographing the night sky. I barely know any of the terms or lingo, but I very much want to get involved! Here's my question: What are flat, dark, and bias frames? How do you create these? Thanks.
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Hi all, first off, still a newbie at imaging and astronomy for that mater. So i'm taking my first steps shooting the moon, with my Skymax 127 and Sony Alpha6300 in prime focus. I also used a moon filter but i guess next time i wont so i can match my shutter speed to my ISO since i've learned that's the way to go. I've shot quiete some pictures in RAW and tried stacking in Lynkeos (Mac over here), following are a single shot and the stacked one (40 shots converted to .png) Does anyone know where the purple/pink is coming from ? I guess one could get rid of it in post proces, but i'm not that advanced in image processing yet. Thanks!
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Hi, can anyone help with star detection in DSS. I have been getting some good images using my Star Discovery 150p and nikon d5100. I'm using a 2xbarlow as I know I can't gain prime focus on this OTA and keeping my exposures down to 25secs due to field rotation with it being a Altazimuth mount and this can also be corrected in processing. The problem I'm having is that when I put everything in to DSS and register the images, it detects hundreds of stars but when I stack them it tells me there's not enough stars and to change the threshold so it can stack more of the images! The threshold is already set all the way to the left at 2% I'm using 100 x 25sec exposures iso 1600, 25 x dark @ 25secs iso 1600 and 25 x bias @ 1/4000secs iso 1600 No matter what I do it will only stack the dark, the bias and 1x25secs exposure! Is there anyone out there that has had similar issues and can shed some light on this please.
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Well, not really actually. For some reason the stacking process produced this strange image. Most likely the image registration process aligned on hot pixels. And since the camera (Liverpool Telescope) is used in two orientations (90 degrees rotation), this was the result. Two colliding galaxies. Or is that three colliding galaxies? Or four? -
I did a test using the same stack of images, but using 5 different stack modes in deep sky stacker... which one is best? I just did very minimal adjustments to them and they all have the same....align rgb, and adjust exposure.... this is a stack of 26 min 30 sec........ 106*15 lights, no darks no flats no bias,,,,,,iso=3200 f7.1 on 50 mm lens........... If someone would like to process them and see what you get out of them that would be great....... I cant really see too much of a difference between the different stack modes All of them have the same file size except the first one the avg stack mode,,,it is smaller.... 2 other stack modes auto adaptive and maximum stack didn't work avg stack modecopy.TIF entropy weighted avg stackcopy.TIF kappa sigma clipping stack modecopy.TIF median kappa sigma stackcopy.TIF median stack modecopy.TIF -
While playing with manual image stacking using GIMP to see the effect on image noise, it occured to me that a short video showing the noise reduction might be interesting to other beginner imagers. (The % layer opacities might not be quite right.) So it's done and can be seen at :
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What are the two axes on the quality graph in AS!2, and what does the length of the grey lines represent?
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Hi all, I captured around 4000 frames in liveview mode while shooting at the Moon, with Camera / 2xBarlow / Telescope. Then cropped them in PIPP and created an AVI file to export after to Registax. The video file, even after cropped and centered, is not very stable (i guess because it was windy?), u can see the Moon is misplaced in a few frames, but nothing really serious, in my guessing. So, when i pass it to Registax 6, i do the normal process that i already did for saturn and for full lunar disc, (Align, choose a decent amount of align points, limit to 95% quality or best frames, etc). Thing is, the final result is something really odd, with the Moon not even entering the final pic. Somewhere along the alignment points process there is a problem that i dont have the knowledge to solve, and you can see the green lines of alignment going way out of the picture for some reason. I only had time to printscreen one shot before coming to work, and looks like this: Some alignment details were, as i remember: default minimum number of pix between alignment points - 30 from edge - 20 chose around 100 alignment points automatically (in some cases, there was one in a black area, but i tried right clicking in order to delete it,but it wouldnt do anything) So, i wonder if i could get any help from you guys! Would be much appreciated. Thanks, Rui
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So here's a thing - it seems to me that astronomy is one of those not very straight forward hobbies. Last night I though it would just be the same as Friday night - set up, look at the moon take some pictures! Simples... Aw but not to be!! I'm good at setting up in the daylight, get my mount bang level (checked with electronic level app on phone...) Get it facing north with my beautiful brass compass and enter coordinates back to Kidderminster from Thame, then you would think just observe... Nah! Moon very wobbly with tinges of green on the edges... Barlowed it and got some superb views of Gassendi and the Hippalus Rilles albeit a bit wobbly... Then the tree came so I thought check out Jupiter the other side of the tree with the camera. Once again folks it appears I have a great deal of Astro luck! Couldn't find Jupes at first, camera in and out of diagonal, EP in and out of diagonal... Shall I just go to bed? Then just before my capitulation - Boom she appears as a large white circle! Mmm something to work on I thought... Messed with the Gain and Exposure, what's Gain mean? Now it's a smaller white ball no moons... Then after another stop and start - Boom!! a ball with bands on... Hello Jupiter my old friend I whisper like a sniper lining up a kill! Brainwave, blue filter! in she goes and Boom again deffo a Jupiter view (although very wobbly) Quick action - click the 'take a picture or million' button... Next quick, take a video or million button. Amazing here I am with a table chair laptop wonderful AVX mount and my Starwave 102 doing EAA.... It's not that clear and it looks like a black spot just above the main band... Er it couldn't be could it? Could it be? Not another transit surely.... Run indoors get the phone check my Jupiter moons app and Bingo is Io, only Io transiting Jupiter... Wonderful how lucky am I? I call my girlfriend down out of bed, look look she's sat at the table looking and and "can you get the image any sharper? Oh that's funny I thought the band's go horizontally".. a quick turn of the camera in the diagonal and she's happy! Flipping heck is it me how can she not be doing the I've just bagged a great target dance?? Amazing, another example for me of when things don't go perfect at the beginning, decide it's better to just give up and then a little while later having a wonderful moment. This hobby never lets me down! So today the result of all that is I have a million pictures (exaggerate a bit there) and not a clue what do so with em apart from maybe trying something I heard of called deep sky stacker... Should be interesting later. What a fun night in the end... never give up hang in there the joys are just a moment away.....
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Hi everyone. I'm currently running Linux on my laptop and just wanted to know the best stacking software is for an amateur to use. I tried installing registax with wine but it didn't work. I've tried out PIPP and didn't really get on with it. So far the only one I've gotten my head around is Siril by free astro. Would like to know what other software there is that works well on linux that is good for amateurs who have just started playing around with this.
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Hello all - Luc Coiffier (author of DeepSkyStacker) has asked me to post his message about new versions of DeepSkyStacker - specifically there is now a 64 bit version The installers can be found here: 64 bit version - https://github.com/L...64Installer.exe 32 bit version - https://github.com/L...erInstaller.exe 64 bit version as a ZIP file - https://github.com/LucCoiffier/DSS/releases/download/4.1.0/DeepSkyStacker64Installer.zip 32 bit version as a ZIP file - https://github.com/LucCoiffier/DSS/releases/download/4.1.0/DeepSkyStackerInstaller.zip (The ZIP versions are provided if your web browser blocks exe file downloads) I (Tonk) will pick up any issues reported here - but Luc would prefer (if possible) for bugs to be reported on the DeepSkyStacker yahoo group - or if not possible you can also use the GitHub issues page found here - https://github.com/L...fier/DSS/issues If you are not yet aware - DeepSkyStacker is now an open source project on GitHub - https://github.com/LucCoiffier/DSS Regards Tonk pp Luc Coiffier
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I'm looking for a simple algorithm to compare astronomical images (of the same sky region) against each other, compute their movement and rotation, to finally stack them. At the moment I'm already having a more or less working algorithm. First I extract all the stars out of an image (including information like brightness and FWHM), and then I walk trough all the resulting "points" and create triangles out of the current point and those two other stars that have the shortest distance to this star. This list of triangles is created for every image. After this I take one image as reference and then I walk through the list of triangles in the reference image to find a triangle in the other image with the same length of each side of the triangle (I also "allow" some tolerance due minimal relative differences of the star positions in each image). For this matches I calculate movement and rotation relative to the reference image. Last step is to find the matched triangles that have to same relative movement and rotation like the other matches. This is done by calculating the standard deviation, sorting out triangles that are not within 1 or 2 sigma and repeat this process until I have a very small standard deviation. The last part, finding "valid" triangles with the same movement/rotation, is working fine. The problem is that sometimes I have only like 2 or 3 "valid" triangles out of 300 initial triangles. All other triangles have side lengths different to those of the reference image. So I assume it's the way I generate my initial triangles which causes the problem. Sortings stars by their brightness and using this data to generate the triangles also doesn't work. So is there a better way to create the initial triangles in all the images? Clear Skies, David -
I've been putting together a stacking program and today I got all the building blocks working (after a fashion) for the first time. Still lots to do of course (tuning, handling of boundary conditions and testing, testing...), but here's the "first light" (with a touch of unsharp mask):
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