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Everything posted by catburglar

  1. Although your pixels are 4.3microns with a colour chip you are sampling every 8.6 microns in each colour because of the Bayer matrix and then interpolating…so if you can guide with the required accuracy to make use of the greater image scale (approx 0.5”/pixel) then you might see some improvement from a longer FL. The RC might be easier for your mount to handle because it’s shorter, but as Alacant has shown, you can get nice images out of a humble f8 Newtonian.
  2. I personally don’t find much benefit from a UHC filter, but my skies may not suffer so much light pollution-my NELM is around 4.5. However I do find an OIII filter works well- even on smaller scopes. As Vlaiv says- it’s a bit more specialist than a UHC, but I find it more rewarding, so I no longer own a UHC filter at all. I’ve tried a few different brands over the years- currently a Castelli from 365 astronomy which has a slightly higher bandwidth than some others and hence better for smaller scopes with less light grasp… Planetary nebulae usually have quite high surface brightness (and there’s quite a few within the range of a 130mm aperture) so I find I can use an eyepiece with an exit pupil of around 1-2mm on the ring, dumbbell and cat’s eye etc in a 90mm Mak. And….just to tempt you a little more- by way of example. One of my Astro “Wow” moments was seeing the whole of the veil nebula in an 80mm refractor with this filter and a 30mm wide angle eyepiece from my back garden- so it’s not just for PN’s. I’ve also seen it in an Edmund Scientific Astroscan (approx 105mm f4ish) with a 16mm ultra wide angle eyepiece to- so for the dim stuff I think a 4-5mm exit pupil is better. I know this goes against the trend somewhat, but based on my personal experience I would recommend an OIII as the first step into filtered views and get away to dark skies for the galaxies, globs and the like rather than use a UHC filter.
  3. I realise this is an old thread, but I’ve just started running this a few days ago with an RTL-SDR feeding in to spectrum lab. I’m planning to let it run through to the end of the Perseids and see what I get… I managed to process a few sets of data in the time when I was tweaking settings, so no real value in the output, but at least the process works so I should be good to go in a week or so. I’ve also been tweaking the script so it can run on a Raspberry Pi (my preferred devices for low power 24x7 operations)…. It’s a bit untidy at present, but I think it’ll work receiving the output as a UDP data stream from GQRX…. Will test that more thoroughly in a couple of weeks if anybody is interested.
  4. I use Astroberry and Ekos. I’ve used Linux OS’s for ages and I am reasonably computer literate. I did get it all working quite nicely with an AZ-EQ5 and canon 600D plate solving the a local astronomy.net install and PHD guiding... But I wouldn’t say it was completely straightforward- there’s quite a lot of ambiguity in the configuration and I had difficulty finding online tutorials that corresponded to the version of EKOS. Once you get your head around it all it works fine, but I suspect the ASI air would be en easier starting point - and it looks like it should support all of your gear just now.
  5. Seeing the whole of the Veil nebula from my garden a few years ago in an 80mm scope with 30mm UWA eyepiece was a breath taking moment for me. I thought I’d ‘give it a go’, but didn’t expect to succeed. However, I’ve struggled with the North America nebula- it’s barely visible in comparison to the Veil which is quite striking...don’t know if it’s my aging eyes or whether it’s the ‘empty’ middle of the Veil that means the contrast against the sky background is greater.
  6. I picked up a Daystar Solar Scout 60 last year, but didn’t get much chance to use it. However this year I’ve had more time, and have to say I’m quite pleased. I was a bit worried by some negative reviews, butI find the images very satisfying. Typically the appearance (visual only) is a bit better contrast than the one shown for El Teide but not quite as contrasts as Cerro Tololo(https://gong2.nso.edu/products/tableView/table.php?configFile=configs/hAlpha.cfg)
  7. For those objects with your camera you’ll need a focal length around 430mm or less (see screenshots- The first two are 430mm, the last is the Samyang 135mm- I use Telescopius.com to estimate the FoV of different scope camera combinations). You are probably better off with something in the 3-400 mm range so you can crop any stacking artefacts at the edge. So unless you’re going for a takahashi epsilon or sharpstar 150 reflector your looking at a small refractor or camera lens WO ZS61 or Sharpstar 61EDPH or WO Redcar or Askar 180 or 200 lenses might do. For the 61mm scope you’ll probably want a flattener, you shouldn’t for the Redcar, but not sue about the others. You could always start off without and see what you think about the corner stars
  8. If you’re not having troubles with guiding and your individual sub lengths are not limited because of tracking errors - then a shorter focal length scope won’t make a difference to your ‘image quality’. But it will give you an option to capture wider fields of view- so it’s a question of how wide you want to go? The 130pds option is about 600mm (compared to around 1000 with your current SCT & reducer), the refractors are around 400mm and the Samyang lens at 135mm is very wide. You might want to check what FoV is required for the targets that you want to shoot. I don’t have any direct experience of the Optolong filter- but if imaging was my bag, I’d be considering that one. It should be fairly straightforward to get some automation using a raspberry pi/Astroberry combo. I used it with a 600D and AZ-EQ5 some time ago-plate solving, guiding and image capture, but didn’t go as far as completely unattended imaging. You might need some other bits depending on how far you want to go- I’d start with an autofocuser, then you might want to get a ‘flip flat’ so you can automate taking flat images, and you might want an all sky camera or something to monitor the weather so you can shutdown safely when the clouds arrive and before the downpour.
  9. Depends what you want to achieve. If you want a wider FoV you could go for a small refractor as suggested above, OR a SW130PDS plus coma corrector OR a Samyang 135 F2 ED lens - and carry on using your DSLR. Also, if you’re sticking with the DSLR, you may want to try one of the dual-band or tri-band filters so you can do a bit of “narrow band” with your colour sensor. You could also try a cooled camera - but with your budget you’d be looking at the used market - there’s an ASI533MC on astrobuysell- it’s over budget, but if you sold the DSLR it might not feel so bad. The sampling rate is a bit high for your focal length, but you could bin to bring it back to somewhere between 1-2 arc sec per pixel. It’s probably true that a better mount would be a good investment in the longer run, but I doubt you’d get anything much better than your current set up for your budget- and if you’re going shorter FL then tracking precision is less important.
  10. I was looking about an hour ago- looks like someone dropped a Boulder into a lava lake and the splash is following outwards in super-slo-mo
  11. It’s not so much whether the binoviewer is any good- I’ve seen a few reviews and looks like it is. The real question for me is how much does it add to the viewing experience? Solar is trickier than I’d imagined it would be- excluding ambient light and finding critical focus on low contrast details specifically. It seems that binoviewers split the audience- some love it and others are less convinced. If I tried a typical binoviewer and didn’t get on with it, then I know I’d be able to sell it on at a relatively smalll loss. But I think for most people the additional premium for the Orion might be a tough one to swallow for a used item, so the loss is likely to be higher.
  12. I'd tried that also and it kept coming back after the restart... BUT... I'd misread your initial post....I was looking for the gpsd conf file in etc and not in _etc_default...changed USBAUTO='false', rebooted and all is OK- gpsd is still running but it's not automatically connecting to the USB device....just what I wanted. I don't think I'll be needing an actual GPS dongle, but if I do then at least I'll know where to put the config! Thank you so much.
  13. Thanks for the suggestion. I don't need the GPS, but I can't seem to disable gpsd....if I run 'sudo systemctl stop gpsd.service && sudo systemctl disable gpsd.service' EKOS connects and everything works OK, but after a reboot of the pi I have to do the same thing again- I thought that if I disable gpsd.service it wouldn't come back up after the reboot.... I'd like to find a way to tell gpsd to ignore /dev/ttyUSB0 - but I can't find a way to do that easily. The only thing I can think of would be to build gpsd from source, but leave out the support for the usb-serial chip (cp210x) that's in cable....but that seems a bit extreme....so I guess I'll just ssh onto the pi and disable it each time I run. It's not a massive issue, but it's a bit irritating and I can't seem to find a good way to fix it.
  14. I'm snookered.... adding a udev rule to make a permanent symlink didn't work disabling gpsd.service and gpsd.socket via systemctl didn't work- they start up again after a reboot and I can't seem to stop that happening (short of uninstalling the packages I guess) I'm planning on using the pi as an indiserver controlling the devices from a Ekos on either Windows or Mac desktop so I'd really like to avoid having to connect to it directly simply to stop the gpsd service each time I startup...but I can't think of any alternative right now.
  15. I don’t know if I need gods at all- the scope doesn’t update the OSwith location data so if I disable virtualgps and gpsd- I guess other apps might not work as expected- butI don’t think that’s a major issue. If there’s a way to keep gpsd running but avoid it locking this device I don’t have any problems.-it would probably be the best outcome. I’ll see what I can do with user rules first.
  16. I'll give that a try, but I suspect I'll just get a different port in use error because there is only one USB device- it's the cable connecting to the scope.... gpsd seems to think the scope will behave like a GPS device and therefore binds to the port even though when I try to get data from it with a GPS client (cgps or xgps) neither can connect. The scope is getting a GPS fix, and updates KStars with the correct location data- so the built in GPS is working and once I've stopped gpsd everything works OK....I just want to stop gpsd reacting to this device.
  17. I'm running astroberry and attempting to control an LX200GPS via Kstars/Ekos. The scope is aligned, connected to the Raspberry pi via a USB cable Whenever I start the pi and try to connect from Kstars I see the error message that the USB port is already in use... I have to manually stop GPSD every time I restart the pi and then Kstars can connect and control the scope without issue. Is there any way I can get the connection to work automatically without having to do this?
  18. I was wondering about binoviewers with the DS-SS60 and came across this: https://uk.telescope.com/Telescopes/Orion-Premium-Linear-BinoViewer-for-Telescopes/rc/1306/p/130875.uts?keyword=Binoviewer....A bit too expensive for an experiment though?
  19. I think the 224 may not a good match with the sct for EVA. Binned 2x2 you’re capturing at approx 1.3 arcsec per pixel and with 200mm aperture, you might not get sufficient signal in the short exposures usually employed in EEVA. With this camera, you probably want a 12 inch (2.25 x collecting area) at f/4 (for comparable image scale) If you could find one of the f3.3 reducers, then you’d be at around 2.3 arcsec per pixel, which could work OK. It’s not too far from the configuration that Martin uses successfully, but you’ve arrived at it by a different combination of factors.
  20. Binning doesn't change the field of view (that's determined solely by the chip size and focal length) but it does change the sampling rate of the image. For DSO's you want bigger pixels to capture as many photons as possible in a 10-30 second exposure and therefore improve the signal to noise ratio at the expense of image resolution For planets- it's the reverse, because they're much brighter, you'll want short frames at max resolution to capture the most detail possible. If you can live with the approx 0.5 degree FoV of the IMX183 chip using the C11 and 6.3 reducer, I think it could be a good combination...particularly if you want remote operation. The other point to note is that for the dso sessions, you'll be going from your 20Mpixel native resolution to approx 1.2Mpixel DSO image if you bin 4x4...but if you choose a chip with bigger pixels, you'll lose out on the planetary. The ASI1600 might also be a reasonable option, binned 3x3 it'll be a little more sensitive than the 183 and won't loose out too much on planetary, and will give a bit more FoV
  21. I wonder if you could still get good results with the large SCT (C11) and 6.3 reducer and something like the ZWO ASI183- with 2.4 micron pixels. If you bin 4x4 gets you 1.1 arc seconds per pixel for DSI’s and then unbinned / ROI for planetary at about 0.3 arcsec per pixel... The FoV for DSO’s will be a little limited, so I think it depends how wide you want to go...if you’re after galaxies, globulars and planetary nebulae, this would be OK, but if you want M31 or Barnard’s loop, then you’ll need something with a shorter fl.
  22. Welcome. I don't know if this sight might be worth a look: https://www.slooh.com/about/about-slooh
  23. I think I saw a comparison between one of the canon L series lenses and a WO Redcat- the results were similar....I'd expect a similar situation here...with some important things to note....they are both 400mm FL and therefore will have the same image scale if used with the same sensor. As you note this means that the RASA will be faster. But, I would also expect the lens to be slightly less sharp if used at it's maximum aperture- this is typical of many camera lenses even good ones. So to get comparable sharpness, you'd probably need to stop the lens down, which would make the RASA speed advantage even more significant. In which case the lens will produce diffraction spikes when you stop it down because the aperture blades aren't circular...You can get around this by using a round aperture mask. So- if you want to operate at 400mm and you want to do it quickly, I think the RASA is a better option than the canon lens, unless you also want something for conventional daytime photography... But I've never used either of these, so I have no practical experience
  24. I started with a 60mm Tesco refractor telescope on a wobbly altaz mount...apparently it was exactly the sort of telescope that you shouldn’t start with according to some.....but it showed me lots of detail on the moon, Saturn and it’s rings, double stars a plenty as well as the Hercules globular cluster, dumbbell nebula and ring nebula...your scope will be fine, and give you lots of things to look at. Like nialk above, I’d also recommend the book Turn Left at Orion- it’s got a nice selection of things you can see with easy to follow instructions showing how to find them as well as a guide to what it should look like...You can get all of this from the internet, but I find it easier to use a paper guide like this to start with...An alternative might be the Celestial Sampler by Sue French, but that’s less beginner oriented in my view...
  25. I was surprised I didn’t have any significant interference for a couple of days to see this so suddenly....but as of about 11:30 it seems to have disappeared....not sure what it was, but will see if it reappears.
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