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  1. Past hour
  2. Hey Carl, I set the dish up and tried an observation. This is my block diagram (electronics chain): Single linear polarization feed -> LNA -> LNA2 (in-line amp) -> 3m LMR-400 low-loss cable -> Bias Tee -> 1420 MHz Bandpass Filter -> RTL-SDR V3 -> 60cm USB extension cable -> Computer I observed for about 6 or 7 hours, with a not-so-proper-but-still-OK averaging (it takes about 5 minutes to go from the "noisy" spectrum curve to the averaged smooth spectrum curve, so you can kind of say that it averages over ~5 minutes). I uploaded the Observation on YouTube (I wrote a quick script that takes screenshots every minute for 6 hours and sticked the images together). I also recorded (unaveraged) Waterfall plots, in case I got a very high SNR and things were also visible in the Waterfall plot without averaging. Any idea why there is no (apparent) detection? I'll admit I was quite a bit optimistic this time with a 1.5m dish pointing to zenith, but I don't think I got anything... I have three suspicions: 1) The feed's monopole is misaligned - I set it perpendicular (90deg) to the grid bars, expecting ~100% efficiency (since the bars will act as a polarization filter, I turned it so I got the most out of what's reflected). If I've done this wrong I'm probably receiving nearly 0% of the incident waves. 2) The software can't extract the emission from noise without averaging for longer (not sure how long you've averaged for to get your results but I didn't expect I'd need over 5 minutes of integration time for a reasonably high-SNR detection). Perhaps I'll need to work with different software or write another GNU Radio flowgraph. 3) The primary LNA is not getting any power (I don't think that's the case cause my in-line is having a LED lit up, so it's definitely getting power - the question is if it forwards the DC voltage to the primary LNA, but I don't think that's the problem - wish all LNAs had an LED on them though, it'd be super helpful for knowing if they get power or not). Here is the YouTube video of the Observation: [to be edited once upload is complete] A few pictures of the setup:
  3. There were no details about when the first one is going to be, but they did say the timing was suspiciously good for the opening of the 2020 Olympics. They see supposed to be a display that can be enjoyed (relative term) over a distance of 200 miles. They did not say if that was radius or diameter!
  4. Thank you Steve! I only see one problem when SGP and PHD2 are running you can not lock on to the com port with Stellarium as its being used and by pressing connected in Stellarium it does nothing. If i shut down SGP then it will connect. So I guess i align it in Stellarium first with APT?
  5. Good comments on technique Dave. I find it's helpful to tell people to adjust the distance between the two barrels of the BV first by just holding it up to the eyes (with eyepieces) and adjusting it by looking at the bright circle of light you will see until both eyes can see this circle - with the BV not in the telescope at first, but pointing at the sky in the daytime. It's also best to start a little away from the eyepieces and slowly move your eyes towards them, many people put their eyes very close to the eyepieces straight away which makes it harder. Also, people can practice using their BV in the daytime to get used to it, pointing the scope to the horizon or as far away as you can to focus. I almost never use my BV on anything but the moon and planets, I also prefer a single wider field eyepiece with good eye relief for everything else. I forgive you for not being a lunar fan Dave - just!
  6. I am very new to all this but I platesolve just like in the video using APT and has revolutionised my sessions so much quicker and so accurate. Usually after polar aligning I will slew to my target take a short image (20 secs or so) platesolve it and it will be out a little but but then click on Sync you then see Stellarium update its position. You can then slew to the exact position you want to image and away you go. And the great thing is if you setup Stellarium with the camera and scope details it gives you an outline of the image on the screen so you can see exactly how your camera is rotated. Steve
  7. Thanks for the advice. Blue is next on my list, looking forward to see if it looks better than L. I'm getting a AT106 loaded with a moonlite focuser and high resolution stepper motor. A friend bought it for me in the US and he's bringing over in May when he's coming to London. Emil
  8. Thanks for comment. Newish, bought End Jan, but only used few times due to weather. I guess I could return. Odd thing is how it seems variable in extent, but always same position in image. I guess I don't want to return it only to find its something im doing wrong like tilt. If consensus is pinched optics I will return.
  9. I am at the very start of my Astro Imaging exciting journey and made a fair bit of progress last night. It was my first full night out with my new Imaging setup. Firstly I connected all the leads and balanced my scope. Played for about 45 minutes with Sharpcap to get my focus and setting right for my guide camera Altair Aor130 Succesfully Polar aligned another 1 hour (First time) Sharpcap showed it as Excellent within 00:00:10. (I nearly gave up) Run and setup PHD2 and Sequence Generator Pro with some help with setting off of youtube. Got my EFW 8 slot wheel working and mount control and Asi1600mm Pro. Spent 1.5 hours playing with it all to finally get it to work. Had a lot of problems with getting SGP to automatically starting PHD2 and guiding. Just said connecting constantly but fixed itself Added my Bahtinov mask and got HFR on my 10 second Lum frames between 0 and 3.0 (not sure this is good. Was around HFR 6.0 and 8.0 before Bahtinov focucing?) PHD2 Giuiding was smooth and was averaging 0.43 total less than 1 arc second. I have had my EQ6 Pro Modified. Tonight I will be out again as the skies look fantastic. But I need to align my scope to the stars. After Polar Aligning I tried to do a 1,2 and 3 star align on my Synscan controller but it always skewed the wrong way and I had to stop it twice as it got close to the tripod legs. I have the correct day, time, long and lat coords dialled in and daylight saving on. I was using ascom on my PC last night to control my scope from indoors. So the question is can I star align my scope another way after Polar alignment? If I used Astro Photography Tool and plate solved and then ran stellarium to fix the point as in this video would I be able to star align that way? Regards David
  10. ZWO developed rgb filters that are optimised for the cameras spectral response, meaning that R is wider than b which is wider than g. 1 s exposure for each filter should give the same adu count, when imaging a neutral source. If your filters are equally wide for each band, you should expose red and blue more than green. But since the galaxies have more detail in the blue region, it makes more sense to shoot more blue (longer exposures?). But if I were you, I'd check wether the blue master shows more detail than the L master in the outer regions. If that's so, consider adding blue to the L master. You'd need an awful lot of blue to make that work. Btw, great image so far. Good luck with what ever you decide on next. Which refractor will be coming your way in May?
  11. It almost has a feel of pinched optics!. is it new?.. can you return it
  12. My employer got so fed up with this option they now send all couriers away, even including work deliveries!!
  13. It staggers me with these delivery situations!. I now have everything delivered to work.
  14. Might be a strain on the arms with a heavy pair of binoculars and you have to beef up the construction using metal tubing instead of plastic. Plus, how would you adjust the focus ? Google "parallelogram binocular mount" for a better design.
  15. Edited with user friendly cropped PNG files rather than FITS!
  16. Optical aberrations aside, it should not. But range does, and there is a difference between 249 kmiles, 250 kmiles, and infinity... Indeed, so.
  17. I have a CPC800 with Starsense. It has not been used for 3 years but GPS still finds position/date after a while. Furthermore I check it on the HC prior to use. Problem: Starsense is working perfectly; all items are spot on in the centre of field using Autoalign. Finds whatever I ask it to on the HC. However, plugging in SkyFi or Skywire after alignment as suggested, the object it way off – 10º to 20º - in both Skysafari 5 or 6 Pro. I have no idea – SF/SW is used on an Ipad mini. The only difference between now and 3 years ago is that the IOS has been updated. 3 years ago all worked perfectly. Any ideas?
  18. AR2738 funeral pyre: Pushed this one much harder in Registax Wavelets. Just trying to get the Quark look at half the price.
  19. I'll double check mine but pretty sure I'm on the latest firmware. Sure that was one of the things I went through. Only ever use it with phd2 and brief spells with sharp cap for polar aligning. Never in sharp cap long enough to notice any issues there.
  20. I agree, Paul, both about the "2 eyes better than 1" point, and also that not everyone can see the benefit of two eyed viewing. It seems that some people can merge two images better than others, and others can't do it at all. I had to persevere myself, and I think I was "trying too hard" to merge the images to begin with. I found that if I opened up the bv's IPD to its widest, and then slowly closed them up while "just looking"-almost like with binoculars, just "expecting" to see a single, mono type view, but with both eyes, then there it was. I hope that makes some sense. I also do think that binoviewers are better with some objects than others: for me, lunar, planets and some doubles show best, while with some clusters I seem to see better with a nice modern wide field in mono mode, but yet others, such as M13, do look great with a pair of good orthos. M42 is an interesting one: my most pleasing ever view was with binoviewers, ie the whole object showed so much detail. But for close up resolution of the Trap, I find that a good single ep works best. Clearly the loss of light with the split beam in bv's does play a part here. I'm not a big lunar fan, but since gasping at the clarity and comfort of the binoview mode presentation the first time I viewed it this way, I much prefer the binoviewer for the Moon..same for Jupiter and Saturn. Strange, isn't it?! Dave
  21. Oh My! I feel your pain... I can get that. As a beginner I fixed a 9x50 finder atop my MAK90. More of a "double telescope"? I could find things at 200x on the "main" scope? Also just "exhumed" my favourite Baader "Skysurfer V" RDF. This has the nice feature of internal adjustment screws against a RIGID finder clamp.
  22. My setup is: Laptop connected to Celestron CG5 GT mount via RS323 COM adaptor (goes to the Nexstar+ hand controller). The laptop has PHD2, Astrophotography Tool (https://astrobackyard.com/astro-photography-tool/) (this allows me to connect a DSLR, control the camera settings, view images, etc) and Carte du Ciel. The mount is ASCOM compliant so I have that installed which connects everything up. Microsoft Remote Desktop app on my tablet. This connects via my home wifi intranet to the laptop So, my choices are to sit outside (shed observatory) with the laptop , controlling everything or sitting indoors with the tablet, checking what is going on. The optimum for me at the moment is to get everything connected and tracking via the laptop directly, then just monitor via the tablet.
  23. Today
  24. Thanks Olly, I love coloured moons, overdone or not
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