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soundwave

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  1. I decided to try and see how the ASI120MM Mini that I bought to guide my SkyGuider Pro can perform photographing planets with my SkyWatcher 250px Manual Dob. ASI120MM Mini SkyWatcher 250px Manual Dob (10") 2X Barlow The planets were a bit low in the sky, and I'm not sure I managed to get perfect focus, but it's close enough I recorded videos of the planets drifting from one corner or the frame to the other, and then aligned in PiPP, stacked in AutoStakkert and processed in Registax. Thanks for viewing.
  2. Hello everybody! I decided to try and take a shot at shooting a small galaxy with my 70-200mm f4 lens + Canon SL3 (250D) + SkyGuider Pro + Auto-guiding. I've only recently started auto-guiding my SGP using ZWO's mini bundle, and so far I'm really enjoying using/testing it. To mount the ZWO guide-scope to the camera, I've designed and 3D printed a clamp-mount for the lens. It seems to work well. I might do a detailed post about it in the near future. Some details: This image was taken from my front yard (Bortle 8-9), under a street light. Integration: 1h10m (28x150sec), ISO-400 10 darks, no flats because I accidently touched the focus ring when putting on the lens cap. Filter: SVBony CLS clip-in. Equipment: Canon SL3 (250D) Canon 70-200mm f4 USM (@f4.5) SkyGuider Pro + ZWO ASI 120MM Mini + ZWO Mini Guide Scope NINA + PHD2 Processing: PixInsight (Cropped). I used a combination of auto-dithering on the RA and manual dithering on the DEC. Basically, I auto-dithered every 2 frames, but every 5 frames I would pause the sequence in NINA, stop the guiding in PHD2, move the DEC very slightly, then resume guiding and the sequence (re-calibration was not needed in PHD2 after stop/resume). While the final image is noisy, the noise doesn't seem to be aligned in any direction (no walking noise). I'm pretty happy with the result, I thought it would turn out much worse Thanks for viewing.
  3. Thank you. The entire session was an hour and a half, during which I took many videos of Mars drifting in view (and then realigning the scope, and repeat). Although when stacking, I chose videos that were all taken within 5min, so that the rotation won't mess up the stack. I was left with 4 decent stacked images, so I decided to make the gif. I didn't have a set interval in mind for the animation frames.
  4. Hello everybody! This is my second attempt at photographing Mars. I'm fairly happy with the result. I was using my Skywatcher 250px + a 2X Barlow & a Canon 550D (T2i) using Movie Crop Mode. Aligned in PiPP, stacked using AutoStakkert, wavelets using Registax. Side-note: After the wavelets edit, there was some sort of a bright brim around the planet (mostly on the left side). I have cropped out that line of pixels. Not sure if it's considered "appropriate" or not. I also stacked some more frames that I took that night, and made a nice little animation (using 4 stacked images) Thanks for viewing! Have a nice day.
  5. I gave Siril a try and came up with the attached result. This is what I did: Background Extraction: I think I used the red channel, and I did an auto-generate of samples and played with the tolerance so it will sample around the galaxy) Color Calibration: I sampled a small part of the background and clicked 'background neutralization', then sampled the core of the galaxy as the white reference and 'apply') Deconvolution (helped with sharpening a tiny bit) Then I did another Background Extraction, because there was still a bit of a noticeable gradient. This time I manually placed the samples) Histogram Transformation: Clicked the auto-stretch button (gear), but it was too stretched for my taste, so I played with the middle & black sliders a bit) Then I saved the image and did a bit more processing in Photoshop: Noise removal (with a lot of color-noise removal) Curves: did a slight S-Curve for more contrast Levels to make the background a bit darker Looking at both results, the Pixinsight photo now looks too beige for my eyes (and this one not beige enough) hehehe So I'll need to work on my color calibration skills a bit more.
  6. In the Bahtinov Mask Generator website? The "aperture" in this context means the diameter of the lens. (I think that's the name that stuck in the astronomy field because telescopes can't change their aperture, it's always wide open to the diameter of the scope, but I'm not sure) So you can set 300mm as the focal length and (I assume) 67 as the diameter ("aperture")
  7. Thank you. I think that Pixinsight did a great job, and you took very nice data. Sometime later I will try Siril for the first time and try to replicate this result there. Here is what I did in Pixinisight: Slight crop of stacking artifacts at the edges of the frame Dynamic Background Extraction (By selecting different background samples, it creates the overall gradient to be removed by division and then subtraction from the original image) Color Calibration (By selecting a white reference, area-of-interest and a background sample) EZ DeNoise (with a background sample) EZ Soft Stretch Range Selection (which is basically creating a mask of everything other than the background) With the mask: Curves Transformation De-saturated the background to get rid of some color noise Saturated the foreground just a little bit Then, without the mask: Curves Transformation Did a small S-Curve for added contrast Export to JPEG
  8. Yes, flats should help a lot with the vignetting and also with some of those dark patches which are probably dust on the sensor. The color in the new image looks so much better. Is there any chance you could upload the stacked tiff somewhere so I could play around with it in Pixinsight? I wonder what more can be done with that image of Andromeda (and I'll list the steps I've taken).
  9. The 60D is the other camera with a 1:1 movie crop mode according to this website: https://www.astropix.com/html/i_astrop/eq_tests/canon_one_to_one_pixel_resolution.html
  10. Welcome aboard! Wonderful start. I had my Skyguider Pro for some months now, and it's a lot of fun indeed. (and I also use the 550d and a cheap tripod with an annoying center-pole). Polar alignment gets much easier as you get more experienced. What is your polar alignment routine? It looks like you are a bit out of focus in your images. I also had a difficult time reaching 'perfect' focus with my 70-200 lens using just the live-view 10x. Eventually I 3d-printed a Bahtinov Mask that fits my lens hood (but you can also make a DIY one) and I highly (HIGHLY) recommend it. Even-though it's not easy to rotate the focus ring by a very small amount, it is possible. Also, am I understanding correctly that these are stacked images without any post-processing outside of DeepSkyStacker? If that's the case, then there is much more you could get out of these image. I've used the free-trial version of Pixinsight along with many tutorials on youtube to remove gradients, color balance, noise reduction, stretching, etc., and it makes all the difference. I later purchased the software, but there is a new (free) alternative that is emerging now called Siril. Cuiv The Lazy Geek did a nice rundown of it here. I also noticed that Flat frames are very important for the final stacked result. You can cover the lens hood with a white t-shirt using rubberbands, then place a tablet or something similar with a fully white screen. I like using N.I.N.A (open-source) to capture my frames, and it also has a very nice Flat Wizard which makes the whole process much easier. You can take flats at home after your return from the field, just be very careful not moving the focus-ring by mistake until you actually take the flats. For easier framing of targets, I would recommend buying this fairly cheap DEC panoramic-head, along with an arca-swiss dovetail (just the plate). I truly dislike the DEC head that comes with the SkyGuider Pro, because there is movement of the target when you lock down the 2 screws. This upgrade saves me a LOT of time with framing, and also allows me to do Manual Dithering by slightly moving the target in the frame on both axis every 3 frames or so. I'm assuming that you are using the counterweight setup with your gear. The dovetail will also open up the option of balancing on both axis. If you need any further help, don't hesitate to message me.
  11. Hello everybody, I wanted to test some new gear I got for the Skyguider, and decided to try to take an image of the Dumbbell nebula, the first nebula that I've ever seen with my eyes a long while ago (using a 10" dob at a dark site). I think it turned out pretty good for a 21min image from a lightpolluted front-yard Gear: Skyguider Pro + Panning Tripod Head (much better than the one that came with the Skyguider) Canon T2i, 70-200mm f4 lens SVBony CLS clip-in filter Acquisition: 7x180sec (21min) @ iso 400 4 darks Manual dithering -- I manually moved the RA/DEC by a small amount to create dithering. Stacked in DSS and processed in Pixinsight. This was the imaging setup: And here is the result (cropped in)
  12. Check your photos' temperature using Dark Master. I've had some raw files that looked extra noisy and I noticed that my camera's chip temperature was over 40c. When it's around 35c, I can get a workable image. I've attached 2 raw images taken that same night: the first one is at 35c, and the second one is over 40c (same settings otherwise). I'm not sure what caused the temperature spike, but you can see the difference it makes. Also, in hindsight, I would have lowered the ISO a bit for that image. _MG_8674.CR2 2020-08-14_01-43-46___150.00s_1.cr2
  13. Thanks! I used a 3d-printed bahtinov mask on the lens-hood to focus. It's not an easy task with a lens focuser, but after some (and some more) fiddling, the center spike was pretty bang in the center.
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