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Hi all, I have been giving some thought to the procedure for next year's project to produce a movie of the Jovian atmospheric movement. Here is my suggested procedure. Please come back to me with any suggestions to improve this or if you have any concerns about any of the practicalities: 1) Time Period for the imaging The opposition of Jupiter is May 9th in 2018. I suggest we aim to do the imaging for 1.5 weeks each side of the opposition. Lets say 23 days in fact, because we can include as many weekends as possible in the timeframe. I am assuming it is easier for people to image during the weekends so the greater the proportion of the time that is on the weekend the better. Can I suggest therefore we start on Saturday 28th April and finish on Sunday 20th May 2018? This gives 4 weekends (8 days) and 15 week days. 2) The Imaging Process Clearly you will all have your own techniques, so the following would not be considered mandatory, but probably the more standardised the approach the better. Telescope: 200mm + objective diameter. The larger the better Imaging camera: Monochrome or OSC but capable of high frame rates 100+ fps RGB filters: Where monochrome any good RGB set up. Luminance generally not required nor preferred Focal Length Multiplier (Barlow or Powermate): Optimal Multiplier = 5.15 x camera pixel size (microns) x objective diameter (mm)/ telescope focal length (mm) This is to ensure adequate sampling Eyepiece projection may also be used to give good results. Seeing: 4 or 5 out of 5 Transparency: minimum 6 out of 10 Captures: I suggest a standard of 60 secs per colour channel for monochrome and 90-180 seconds for OSC. The videos thus produced do not need de-rotation prior to stacking. If you want to take longer videos, then you will have to de-rotate the videos before stacking using WinJUPOS. I use Firecapture to manage the capture process and it is an excellent piece of software. The ability to crop to a small Region Of Interest (ROI) around the planet allows much higher frame rates to be achieved. The higher the frame rate the more data to improve the signal to noise ratio. Imaging run duration: As long as you can manage. The longer you capture the more of the planet you are seeing as it rotates and the better the planetary map we will be able to generate, especially if you encounter good seeing. I generally aim for as high a gain as possible, zero gamma and set the capture rate to give a histogram level of ~ 80% 3) Image Processing - Quality Assessment and Stacking I think we all use Autostakkert to quality assess and stack the videos. RegiStax is also a possibility, however, I have found file size an issue and it is less stable than Autostakkert. I also understand that there is consensus that Autostakkert produces superior results. You will no doubt use your own settings, but i would expect you would use Planet (COG) for image Stabilisation. For the Quality Estimator I would use Gradient, Noise Robust: 4 (if the seeing is good enough this should be fine) and Local (AP). After doing the Quality Assessment, I generally set the frame percentage to stack around the point where the Quality Graph drops below 50%. I have looked at a variety of frame percentages to stack which is a balance between more data and less noise against including poor data. I have generally found that the 50% Quality on the graph corresponds well with the optimal frame percentage to stack. However, feel free to bracket if you want or use your own criteria. When it comes to stacking I generally select an alignment point (AP) size to get 15 - 25 APs. 4) Image Processing - Wavelet Processing In order to sharpen the stacked image there can be many techniques. I use RegiStax, but you may have a different approach. The exact process to sharpen the image is highly subjective. What I do is to select Linked Wavelets. The first slider I push to ~ 40, the second to about 15 and the third to ~ 5. Depending on the seeing this sharpens but introduces noise. I then use the noise reduction on each slider, most on the first, until the noise has been reduced to an acceptable level. The zoom feature is useful to see the noise. I then play around with sharpening and de-noising until I achieve an acceptable result. It is useful to save the settings to apply to each image if RegiStax crashes. I then look at the histogram. I bring in the slider from the right until it reaches the histogram and press "stretch". If necessary I move the central slider to marry up with the peak of the histogram. This just seems to give a good exposure for me. 5) Image Processing - De-rotation I think we all use WinJUPOS for this. I don't there is anything in particular to standardise for the process, except image size. For OSC outputs, when you do de-rotation of images can I ask that you select a Quadratic Image Size of 600 pixels. For monochrome with RGB, please also select this size when de-rotating images for each of the RGB channels and again when you are doing the De-rotation of R/G/B frames. This will ensure that we are dealing with a consistent image size and minimise the image measurement work when combining the images from multiple imagers to create a planetary map for each day. 600 pixels gives the planet occupying ~ 80% of the frame. Please also select North UP, so the images all have the same orientation. I generally like to de-rotate and compile the monochrome outputs from 6 RGB runs. This gives me significantly better resolution than from a single RGB run, depending on the seeing. The resultant RGB combined image which has a time stamp at around the centre of the 6 runs, can be sharpened again with RegiStax. I generally start with half the slider levels of the first round. That is for first slider I push to ~ 20, the second to about 8%and the third to ~ 3. Again depending on the seeing this sharpens but introduces noise and I use the same process as previously successively de-noising and sharpening until the result looks satisfactory. I then RGB Balance in RegiStax which always improves the colour of the final image. 6) Image Processing - Finishing If there have been any moon shadows creating a black smudge, you may choose to use something like Photoshop to remove this from your final image (s). Equally if you've ended up with some unwanted processing artefacts please feel free to eliminate these in whatever manner you see fit. However, if you don't want to do this, you can just submit the images with the blemishes and I can clean them up if required. Where you have done multiple imaging runs and therefore have images that cover more than 180 degrees of the planet, then please generate more images from across the run to include more of the planet. So for example, supposing you have been imaging for 2 hours. During this time the planet will have rotated 2/ 10 ~ 70 degrees, so your images will cover 180 + 70 =250 degrees of the planet's surface. You could arrange the number of runs that you compile in WinJUPOS so that you cover the surface with three good colour images. For example one image from 0 to 180 degrees , one from 35 to 215 degrees and the next from 70 to 250 degrees. This way when combined with the output from other imagers we will have the best chance of getting coverage of the whole planet each 24 hours. 7) Image Submission So your aim will be to produce a number of high quality colour images of Jupiter each day you can. Don't worry if you can't due to personal commitments, weather or seeing. I would expect that you only succeed a proportion of the time. I will give you a DropBox link and you will be able to upload your images to there. I think that will be easier than uploading them to AstroBin, although you can do that as well of course. 8 ) Planetary Maps Hopefully each day I will be able to produce a planetary map of Jupiter from our combined images. Over the 23 days we may have some gaps and I am hoping to access some image morphing software to produce an "intermediate" map for those days, such that in the end we can make a movie showing the evolution of Jupiter's atmosphere over nearly 3 weeks. Please come back to me on this. |
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Perfect SOP (Standard operating procedure) for this project. Fully agreed. Lets do it! ;) Almir |
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Great! Thanks for the feedback Almir. |
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| According. Procedure confers with mine. I'm just a little disheartened by seeing conditions here ... but let's go !!! 8) |
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Thanks Newton. Yes, the seeing is the reason we will need quite a few imagers. I too was feeling somewhat disheartened recently and then we had a few nights of excellent seeing. Let us hope that next year the weather is kind to us. ;) As an addendum to the procedure I should add that a 24 hour day starts at 0:00 UTC. I was also thinking that we should get people to submit all their images from a run. So for example, if like me you do 6 RGB runs to create a single colour image with a date stamp at the middle of the imaging timeframe then you would submit 1 image, spanning 20-30 minutes of imaging, depending on the time between colour channels. If however you had a long night of good seeing, such that you were able to do 24 RGB runs (4 lots of 6), then you would submit 4 colour images, one for each RGB run and covering approximately 2 hours. If we standardise on 1 colour image per 6 RGB runs, or 6 OSC runs, then that would give us the most quality information. |
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I'm looking forward to contributing to this very interesting project. When I saw the APOD video of Jupiter I immediately thought of this. Thank you |
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Thanks Mark |
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First of all, let me say I am so glad to be part of this project. Thanks!  Great SOP! May I add one thing? Try TopazLabs-TopazDeNoise software. It seems magic to me; it removes noise without compromising the sharpness of the image. |
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Thanks Massimiliano. I'm glad you are part of the project as well. Thank you! Funny that I have just written the document in Word and I did include exactly your suggestion on using Topaz Denoise 6. It does a great job on removing noise, although one thing i found is that it reduces image clarity and resolution near the limb. Maybe this is a function of what I'm doing. Have you had this issue? |
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| My guess, based on my experience, is that what you are talking about happens when the stacking is not "good enough"; alignment points close to the edge of the planet make this happen... |
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Hi, Niall I use topaz denoise and did not have this problem ...  |
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I don't think it's a stacking issue, since the details look good before the denoise. Maybe I need to play around some more. |
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Hi, Niall Almir informed me of your project. I am based in South Africa(between Pretoria and Johannesburg) and spend most of my time on Mars, Jupiter, Saturn and lunar imaging. I am trying to plan a trip to the UK with my daughter next year which could possibly clash with the timing of the Jupiter opposition. But I would be happy to contribute what I can. |
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Hi Clyde, Your contribution would be most welcome. Thanks for making contact. The project will run from April 28th to May 20th. If you can contribute during that time great. Of course there are no expectations on anyone, because of the vagaries of personal availability, weather seeing, planet altitude. Could you send me your email address and I will add you to the Group, giving you access to my DropBox folder. In it you will find sub folders for each date and one called "TEST". Once I give you access perhaps you can put an image or two in there to make sure it is working for you. I also wrote a Standard Operating procedure, which I'll send you. Thanks and welcome aboard. Niall |
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Hi Guys, I just watched your video and it looked great. The issue I have is, I think my setup (8in Newtonian + DSLR + Barlow) broadly complies with your multiplier, 5.15 x 5.48um x 200mm/1000mm = 5.6 multiplier and I used a x5 Barlow (admittedly quite a cheap one) and here is my result, which clearly doesn't get anywhere near your standard.  Jupiter on SGL My suspicion is focus (unless you think it is something else). So my question is what procedure do you use to get good focus? And could that be specified in your operating procedures? Regards Steve |
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Hi Steve, Focus is always an issue and the worse the seeing the harder it is to get good good focus. Having said that, unless the seeing is excellent you won't get a great image anyway. I have used a couple of methods. The first involves slewing to a nearby star and then using a Bahtinov mask to get good focus. This is alright for a One Shot Colour (OSC) camera, but I have found when using a monochrome camera with filters, the focus can be slightly different for each filter. Now I just use a fine adjustment crayford focuser to make the adjustment for each run by eye and if the seeing is good this normally doesn't present too much of a problem,. Having said that I doubt your issue is focus. I never really achieved any decent images with a DSLR. It wasn't until I went to a dedicated planetary camera (ZWO ASI 174MM) with RGB filters that I started to generate good images. The use of Firecapture as the capture software where you can crop the Region of Interest right around the planet allows very high frame rate captures, so you get a lot of data, with minimal file sizes. When correctly processed it is amazing the detail that can be brought out. I also can't over-emphasize the importance of the seeing. For me this is always the single biggest determinant of the final result. I hope this helps. Regards, Niall |
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Niall MacNeill: Hi Niall, Thanks for your response. At over 600 GBP, it looks like I will be an observer only of your splendid project. Never-the-less, I will be endeavouring to improve my images when Jupiter next comes into view, I have a small cheap planet cam which do better than the DSLR. I'll give it a try and at least try to follow the other parts of your SOP correctly. Good luck, I hope it goes well. Regards, Steve |
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I have a Canon EOS DSLR. If you do have an EOS as well you can download eos_movrec to capture video directly to your PC. you can use the 5X zoom, which gives 1:1 pixel resolution, so there is no loss of data, unlike normal movie recording with a DSLR. It also gives a larger image scale, although the pixel resolution equation and the required Barlow is unchanged. Good luck Steve. |
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Niall MacNeill: Mine is a Nikon D5000, but I looked up eos_movrec and it provides you with the source. I already have home-brewed code to talk to my Nikon, and maybe I could replicate the functionality of eos_movrec in it. That would be very cool. Thanks for your support. It's a very grand project. If you took the same point in Jupiter's rotation for the whole of the 23 days you'd have about 55 frames. It would be interesting to watch how a specific point developed every 10 hours, maybe you could some morphing software to fill in the blanks. Regards Steve |
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| The original aim was centralise the GRS and only look at the motions around that, but we figured we might as well capture images of the whole planet and use WinJUPOS to hopefully create planetary maps for each day. I think it unlikely we will get good data across the whole planet for each day, so yes the thinking is to access some morphing software, which has been successfully used in past efforts. |
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Let´ s Do! I got a lot of problem with ground vibration last season,I have thought in change my location of capture,have a lot of traffic on my street,I need solve this problem...I´ m thinking of changing my location sorry for my english Regards Newton. |
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Your English is great Newton. Much better than my Portuguese. It's hard to imagine your images being any better than the ones you produced this year. But yes vibration can be an issue. My pier has a deep concrete foundation 1m x 1m x 1m which is below the slab level by ~ 0.3m. The pier has a clearance of ~ 20mm from the slab. Originally I had a tripod on the slab and found the vibration from my own walking around to be the issue. Are you sure it is coming from the street? Regards, Niall |
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my house has two floors and my tripod is on the second slab, it causes a lot of vibration with the cars in the street or even in my house. Thanks Regards. |
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my house has two floors and my tripod is on the second slab, it causes a lot of vibration with the cars in the street or even in my house. I'm sure you've seen these: Anti-vibration pads But they're just like big pieces of rubber in plastic shells. You could make your own. I have the cheap ones and I don't think the expensive ones will be any better. Eye hospitals do the same thing, amazingly. If your whole building shakes like an Earthquake, then they probably can't help, but they should dampen the traffic vibration. Steve |
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| Ouch. That does sound like a problem. |
