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Found 10 results

  1. When talking 32-bit files I normally feels that I'm safe with big margin to not clip any information in my astro image files when workning with them. But is it really so? After some discussing I feel, why not try to make a Bit Resolution Calculator? Here is my new Bit Resolution Calculator: http://www.astrofriend.eu/astronomy/astronomy-calculations/bit-resolution/bit-resolution.html For sure there will be some mistakes in it. I correct it when I found something. The calculations are also simplified. I'm a little bit surprised over the result, but still in the safe area when not doing something extrem. Note this is a theoretical simulation and in real life there are a lot of noise that mask the rounding errors. But still interesting to test what happens in different situations. /Lars
  2. Ben the Ignorant

    Reconstruction worker wanted

    I made a lot of eclipse shots that turned out too dark because my Samsung phone camera is not sensitive enough (400 ISO), but treating these shots as deep sky images, stacking them and doing the processing magic, is it possible to make a few presentable views? If someone is willing to try - no need to lose sleep over it - I'm posting the images by groups. Each group contains pics made seconds or tens of seconds from each other, not sure if the slight differences will make processing too hard. They were made with a Celestron 5 and an Explore 24/68 eyepiece. Focus seems to be accurate. First group Second group Third group Fourth group Fifth group Sixth group Seventh group Last group
  3. Hi, I'm doing some planning for my first mosaic of M45. There is lots of good and helpful advice out there about framing and shooting and I'm fairly sure that I'll use MS ICE for the stitching. My question is about processing. When I get my tiffs out of DSS should I go directly to ICE and do my processing on the composite in my normal way or do I need to do any processing on the individual images first? Any advice welcome. I'm hoping stitch first and process later - I can't see how I'd get the panels looking similar enough to each other for the whole thing to look coherent if I was doing stretches etc before stitching. Thanks.
  4. One of the challenges in image processing is getting the required colour in you image without spending half a day playing around with curves, saturation levels etc. There are a number of tools available in most image processing packages that allow you to match colours from one image to another. However what is really wanted is to be able to match your image to another colour pallet (e.g. Hubble or ESO etc) so you can mimic some of the more iconic images from the data you have collected. One tool I have found that performs an excellent and every quick job of mapping one image to another is Mathematica (http://www.wolfram.com/mathematica/) a very powerful general purpose mathematics package that also does image processing in a programmatic way for those that enjoy doing a bit of coding. The process is pretty straight forward and only requires 6 lines of code. I have included a snap shot of the work I recently performed on M42 taken under hostile Wimbledon skys using an unguided C6SE on an alt-az mount. The steps to obtain a processed image are given here: 1) Load RAW image (in this case from DSS without adjustment / cropping etc) 2) Load Pallet image NOTE: The pallet image should have quite similar characteristics to your image in terms of FoV if possible this will help get the desired background as well as foreground. 3) Investigate the image histograms of your image and the pallet image. Check that the pallet image has the required bit depth, else there could be problems. Mathematica allows smoothing functions to remove the issues around the discrete values seen from low bit depth images or images taken at high ISO (this will be shown in subsequent posts) 4)Finally perform the image transformation - in Mathematica this is know as the HistogramTransform Then the image can be exported for final processing in your favourite point and click photo editor. Here is the final image This was taken from my back garden in Wimbledon on 10 Jan 2014, Celestron 6SE x0.63 reducer - alt-az unguided , Canon 1100d unmodded 34 x 24s, ISO 800 (25 darks, 5 bias frames taken using the laptop held up to the telescope !). So even with modest equipement and light polluted skies some powerful image processing can give you some great images. I will follow up with some more pallets and techniques to improve the final images in later posts.
  5. Here my last video. You can watch at the evolution of a solar image through several stages of processing, from what you usually see in the telescope up to what you find in the final image. The effect of seeing of the first clip is evident and even if there are few moments where you can understand the structure and details, they are ususally blured by turbolence; in the frames stacking you already notice a superior quality, no noise or turbolence, while in the wavelet stage you can finally discover the inner details normally not visible. The last animation is the final work, colored and tuned to show better. I used as subject a close up portion of the Sun of 26 May with the evolution of a huge prominence during an hour of observation. Images taken with a 100 ed refractor using a Daystar h-alpha filter at a focal of 2000mm. Hope you enjoy it and will follow my channel. Follow YouTube Channel
  6. I think I could do with some advice on my use of wavelets (and the rest of my processing probably) in Registax 6 for Jupiter. I either get a really soft image with little detail, or an ugly over-processed image to bring out more details. These are my latest 2 images from last night. I pre-process in PIPP and stack in Registax 6. You can see the un-waveleted TIFF version here. Can anyone get more out my image than I can because I'm stumped. Is there more to come out or is the original video not good enough? (Image captured using Skymax-180 and DBK 21AU618.as, 60fps, Y800 raw.) Thanks for your help. Mark
  7. Here is a project I have thought about over many years. What can I do with all scientific data that are out there? I tested this already 15 years ago with the POSS-I data from Mount Palomar observatory with good results. Now I'm just practising this how to handle the data and get something out of it. One easy task is just to make pictures from the data and compare it with my own photos. Just to get an idea how much worse my photos are compare to the telescopes at Mount Palomar. Here you can see how I have processed the first two Messier objects, M1 and M13: http://www.astrofriend.eu/astronomy/science-data/science-data.html Even more exiting is if I'm in the future can do some science with it. I have many cloudy nights so I'm desperate! /Lars
  8. I am interested in improving my image processing techniques, but I do not have clear enough skies or good enough equipment to capture my own images to process. If anyone is interested in sharing their unprocessed images so that I can practise editing them I would be grateful, thanks
  9. GreatAttractor

    ImPPG (Image Post-Processor)

    ImPPG has moved to GitHub: http://greatattractor.github.io/imppg/ ImPPG performs Lucy-Richardson deconvolution, unsharp masking, brightness normalization and tone curve adjustment. It can also apply previously specified processing settings to multiple images. All operations are performed using 32-bit floating-point arithmetic. Supported input formats: FITS, BMP, JPEG, PNG, TIFF (most of bit depths and compression methods), TGA and more. Images are processed in grayscale and can be saved as: BMP 8-bit; PNG 8-bit; TIFF 8-bit, 16-bit, 32-bit floating-point (no compression, LZW- or ZIP-compressed), FITS 8-bit, 16-bit, 32-bit floating-point. ImPPG can also align an image sequence, with possibly large and chaotic translations between images (aligned output images preserve number of channels and bit depth). This can be useful, for example, when preparing a solar time-lapse animation, where subsequent frames are offset due to inaccurate tracking of the telescope mount. Other possible applications are smoothing out of terrestrial landscape time-lapses or preparing raw frames (with serious image jitter) for stacking. ImPPG is free and open-source, licensed under GNU GPL v3 (or later). Building from source code (C++) requires Boost, wxWidgets and (optionally) FreeImage & CFITSIO libraries and is possible on multiple platforms. Windows executables (32- and 64-bit) can be downloaded using the links below. See the README file for details on usage and building. Screenshots: Sample results (processing and animation alignment): Image processing tutorial Solar processing tutorial by Michael H.F. Wilkinson Astrobin users can add ImPPG to their “Gear” list: imppg Files: imppg-src.zip: source code imppg-win32.zip: Windows program (32-bit) imppg-win64.zip: Windows program (64-bit) If you are not sure what you need: download the latest imppg-win32.zip, unpack it and run imppg.exe. Version 0.5 and newer: go to http://greatattractor.github.io/imppg/ Version 0.4.1 (2015-08-30) Enhancements: – Numerical sliders use 1-pixel steps instead of hard-coded 100 steps – Output format selected in batch processing dialog is preserved – Unsharp masking not slowing down for large values of "sigma" – Increased the range of unsharp masking parameters Bug fixes: – Invalid output file name after alignment if there was more than one period in input name – Crash when a non-existing path is entered during manual editing – Program windows placed outside the screen when ImPPG was previously run on multi-monitor setup – Restored missing Polish translation strings imppg-src.zip imppg-win32.zip imppg-win64.zip Version 0.4 (2015-06-21) New features: – Image sequence alignment via solar limb stabilization – FITS files support (load/save) – Zooming in/out of the view Enhancements: – View scrolling by dragging with the middle mouse button – Logarithmic histogram setting is preserved Bug fixes: – Tone curve in gamma mode not applied during batch processing imppg-src.zip imppg-win32.zip imppg-win64.zip Version 0.3.1 (2015-03-22) New features: – Polish translation; added instructions for creating additional translations Version 0.3 (2015-03-19) New features: – Image sequence alignment via phase correlation Enhancements: – Limited the frequency of processing requests to improve responsiveness during changing of unsharp masking parameters and editing of tone curve Bug fixes: – Incorrect output file extension after batch processing when the selected output format differs from the input Version 0.2 (2015-02-28) New features: – Support for more image file formats via FreeImage. New output formats: PNG/8-bit, TIFF/8-bit LZW-compressed, TIFF/16-bit ZIP-compressed, TIFF/32 bit floating-point (no compression and ZIP-compressed). Enhancements: – Enabled the modern-look GUI controls on Windows Bug fixes: – Selection border not marked on platforms w/o logical raster ops support (e.g. GTK 3) Version 0.1.1 (2015-02-24) Bug fixes: – Blank output files after batch processing when L-R iterations count is 0 Version 0.1 (2015-02-21)
  10. Hi all, To date I had been satisfied taking single shots with a DSLR and quickly seeing features of nebulae and fainter stars or moons of planets that I could not see at the eyepiece. Now I wanted to see what I could manage with further processing on a computer, so I took some pictures of M8 with a Canon EOS 700D on a NexStar SLT102 altazimuth refractor. I took about 20 30 second exposures at ISO 1600 and managed to get 6 with reasonably round stars. I then used Siril (because I have Linux on my computer and could not get DSS to run using Wine) to stack these after some issues. Siril appears to need to convert the input files to FITS format and also creates the final stacked image in this same format. It has features to then convert to others like JPEG but I found that the only way I could see the effect of the stacking was to open the final FITS file in KStars' viewer. I used the auto stretch feature of this viewer, then took a screen shot of that to which I applied a Gaussian blur filter and scaled down in size with Gimp. I ended up with mixed feelings at the end of this foray. This work flow is definitely not ideal. The final result reveals more than a single shot from a technical point of view but I do not really like it aesthetically. If the reddish background "speckling" is part of the nebula I would appreciate any advice on how I can get a smoother appearance (or how to remove it if it is noise). Cheers!
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