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Somerled7

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Everything posted by Somerled7

  1. Thanks for all the replies. In the end my night was scuppered not by a computing problem but a mechanical one - my mount was tracking weirdly, and when I opened it up I had a badly deformed belt drive. So I need a new belt and am in discussion with Rowan Engineering about what went wrong. My experience of astro-photography is that everything is a potential problem - it's just a question of which problem manifests itself on any given night!
  2. Yes, I could have tried a more 'manual' approach. However this was only one of several problems on a frustrating night that ended with me giving up! I know what the source of the other problems were, but couldn't figure out the plate solving issue and wondered whether there might be some setting in APT or ASTAP that I had forgotten about.
  3. Thanks Paul - yes, I was more successful the following night, so hopefully a one-off.
  4. I didn't try that as I don't have another plate solver set up - something I should do in case of problems. Anyway, tried again last night and it plate solved successfully, so no idea what the problem was.
  5. Last night I came across a problem with APT trying to plate solve to the Lobster Claw Nebula. I have an HEQ5 connected via the Synscan wifi module and I'm using the ASTAP solver. Usually it works fine, but this time it solved the first image than said it could not move the scope to the new location. Here's the APT log after the solve:- 2023/11/28 23:32:00 (UT 2023/11/28 23:32:00) DBG RelativeGoTo - SRa:23.256415317, SDec:60.174225994, TRa:23.254444444, TDec:60.174166667, RRa:22.345884323, RDec:55.016101837, NRa:24.164975438, NDec:65.332290823 2023/11/28 23:32:00 (UT 2023/11/28 23:32:00) OpErr Cannot slew to coordinates. Exception occurred. 2023/11/28 23:32:00 (UT 2023/11/28 23:32:00) OpErr PointCraft Error: Can't move the telescope. So the solver worked OK and showed the scope was off by about 1 unit in RA and 5 in Dec, but then it failed to move. I tried changing the target Dec to a random value of 55deg and it plate solved to the location no problem, then re-tried the Claw Nebula location again at dec 60deg and the same failure. For some reason, it seemed like it didn't like those particular co-ordinates! Any ideas?
  6. The Crescent Nebula in Cygnus. I have been trying to get into Narrow-Band imaging for about a year, gradually adding a cooled mono camera, filters, filter wheel and electronic focuser to my kit. I have finally got everything working together (almost!) and have something I think is worth sharing. This is an HOO image with 1hr 15min of H-alpha and 1 hr of OIII. I had hoped to get twice that amount but I left the kit running unattended and when I came back the camera had hung up on downloading images, so I lost a couple of hours. I think it was an intermittent USB problem, so still some things to sort out! Equipment: Skywatcher HEQ5 mount, Altair Astro EDF72 scope with 0.8 reducer giving F4.8 at 345mm focal length, Altair Astro 183MM cooled camera, Baader 7nm H-alpha filter and 8.5nm OIII filter. I've used minimum gain and 300s subs to try to avoid saturating the stars, which I find happens very easily with this camera. I think I still need to experiment with the spacing behind the field flattener as the star shapes go off in the corners, but I don't think they are too bad until you pixel peep. Any suggestions for improvement welcome.
  7. Yes. After the 'big 3' of Andromeda, Orion and Pleiades, the next targets like the Heart, North America and Flaming Star are much harder with an unmodified camera.
  8. I've been slowly upgrading my Astro kit for about 18 months now, and the most recent upgrade was to astro modify my little Canon EOS100D camera. I've also bought a Baader 7nm H-alpha filter for use when the moon is up. I'm now experimenting with combining H-alpha and RGB images, starting with the Flaming Star nebula. I managed 11 hours of H-alpha (15min exposures) over 2 nights under a 70% moon. The RGB data is 2 hrs 30 mins (5min exposures) taken a while ago. Unfortunately they were at different focal lengths - 432mm H-alpha and 300mm RGB, and don't even entirely overlap, so the bottom right side is lacking RGB data. I've stacked in DSS and processed in Photoshop, adding the H-alpha as a luminosity layer over the RGB data and manually aligning the stars as best I could! I know I should gather better quality RGB data at the matching focal length/orientation, so that's the plan for the next clear moonless night, but any other advice/feedback welcome. Camera: Modified Canon EOS100D, Scope: H-Alpha - Altair 72EDF, RGB - Canon 300mm F4L. Mount: Skywatcher HEQ5. H-Alpha Filter: Baader 7nm, RGB Filter: Astronomik CLS clip-in.
  9. Haven't been back to check replies because I've been busy elsewhere. I ended up with different exposure length subs by accident rater than design. Looking for something to image under a bright moon (mainly for practice!) I opted for the Double Cluster in Perseus. As the moon was bright, I took shorter subs than I normally use to avoid over-exposing the sky. I had some older images with longer subs of the same subject, so was looking to see if I could combine them. In the end, I stacked each set separately, then overlaid and combined in Photoshop - interesting to see the noise reducing as the two stacked images were combined.
  10. I've been taking a look at SIRIL for stacking and initial processing, but run into a problem of stacking images with different exposure times. In DSS there are different tabs to group Light files along with their corresponding Dark Files, but I don't see anything similar in SIRIL. Is it a case of throwing everything in and the program sorts it out, or is it necessary to stack each set of images separately then combine the final stacked results? Can anyone advise?
  11. In my first winter of Astro-Photography, I've wanted to at least get decent images of the 'big 3' - Pleiades, Andromeda and Orion. Sounds easy, but it's surprising how much clouds and the moon get in the way - this hobby would be a lot easier to learn if there weren't 4 weeks between each outing! Anyway, here finally is my best effort on Orion. It's only about an hour of total integration time, but ClearOutside was lying when it promised an entirely clear night - after a couple of hours the clouds moved in and by the time they cleared, Orion was sinking behind the neighbours house. 21 x 200s exposures at F6, ISO400, with darks, flats and bias. Stacked in DSS and edited in Photoshop. I've tried extracting the stars with Starnet++ part way through the edit, then re-introduced them at the end. I was quite pleased to start to get some of the darker brown dust showing up. Unmodified Canon EOS80D, Altair Astro EDF72, HEQ5 Mount, QHY5LII GuideCam, Altair Astro 60mm Guide Scope, Pegasus Power Box, Bortle 5 skies.
  12. Thanks for the feedback - you have looked closely! Immediately after posting the image, I spotted the sensor spot directly above the galaxy, but I didn't see the other two. Easy to correct using the Photoshop healing brush, then bring the stars back - we don't want an interstellar incident by destroying someone's star! Point taken on the blues, which I had also noticed when compared to other people's images. I don't think I've got enough detail in the outer reaches to capture much of the blue, though I could adjust the colour balance slightly.
  13. I did use dithering, but just the default levels from APT. Maybe I could look at something more aggressive. Update - Just checked the APT settings, and the default dither level is very small, so I obviously didn't dither enough (though my wife would probably say otherwise!!)
  14. After getting a Pegasus Power Box, some dew heaters and a 12V Leisure Battery, I can now shoot all night without worrying about due or running out of camera battery power. Tried it out on Andromeda for 6 hours before it disappears into the west, and here's the end result. 43 x 500s exposures. 25 x 500s Darks 50 x Flats 50 x Bias Equipment is a stock Canon EOS80D, Altair Astro EDF72, Skywatcher HEQ5, Skywatcher Light Pollution Filter, taken with APT and PHD guiding, stacked in DSS and edited in Photoshop. Taken under Bortle 5 skies (Sky Mag 20) at about -2degC and 98% humidity. I'm very pleased with it as I think it's the first time (since re-starting this hobby in May) that I've got a set of Lights which are not compromised in some way (eg full moon, dew on the lens, dodgy star shapes etc). However, all the experts on here can probably see lots of problems with what I've done or not done, so feedback welcome, as it's the only way to progress. Also interested to know if there would be any benefit in gathering even more hours exposure to add into the image - I plan to keep the raw files.
  15. It's a good point about processing skills improving. However I'm still finding that my subs are often compromised in some way - last few attempts it's been dew and moonlight, not so bad to ruin the night, but not really good enough to re-use if I get better data. So, if I get some good subs, I'll keep them, otherwise I think I'll just process to the best I can, then move on.
  16. Thanks Vlaiv. Thinking about it a bit more, I don't think it's dew or ice as the stars remain sharp across the image. As I mentioned, the dark corner is a similar exposure to the earlier images, so probably there's extra light shining on the left of the frame. The moon was out and quite close to the Pleiades, so that's the likely culprit (though it was equally close all through the night!) To be honest, with the bright moon I was really only testing my new dew heaters - I wouldn't normally shoot so close to a bright moon.
  17. Does anyone have any thoughts on this background gradient? These are 2 Raw images from a sequence of 75, which I have done a very quick and dirty stretch on just to show the problem. The first was taken at about 8pm and the background is fairly even. The second was at about midnight and there is an obvious band with the bottom right corner looking darker than the rest of the image. This banding appeared gradually over the last 25 images . It's not cloud as its present over a long period. I wondered if it might be dew/ice over part of the lens? It was quite frosty, and in fact this was the first time I was using dew heaters. When I packed up, I checked the lens and it looked clear to me, but maybe I didn't look hard enough. Another thought is light shining into the scope? Comparing all the exposures, it's the bottom right that is 'correct' ie it's the rest of the image that has lightened as the evening progressed.
  18. A question about Deep Sky Stacker. If I wanted to image the same object over several nights, do I have to keep all the original light files and re-stack everything, or could I just retain the Autosave.tiff file from the first night, then re-load it and add more light images? It would obviously save a lot of storage space if the original raw images could be deleted once they've been stacked. I'm using a standard DSLR at the moment, so just thinking of adding more raw files to extend the total exposure time.
  19. Here's a comparison of the new and old boards. At first I thought they had sent the wrong item, so I e-mailed Microglobe, but no reply. I then found another thread here on Stargazers Lounge where someone had been sent the same new board from Microglobe and they reported it worked OK. I haven't tried it out at night but the handset runs through the setup OK, and when I do a star alignment the mount slews in a 'convincing' manner, so it looks OK. I still have the old board, so I can send that on sometime after the Christmas/New Year period.
  20. So, an update on my dead HEQ5. I've bought a replacement board from Microglobe - as noted in another thread on here, this looks like a more modern version compared to the original Skywatcher board. I've fitted that (and did the Rowan belt upgrade at the same time as I had the motors out to fit the board). The handset now connects to the mount OK and I can slew it about, though I'll need a clear night to try it out properly (and who knows when that will be)! However, I still can't get the Synscan WiFi adaptor to connect to the mount. I can connect my phone/pc to the adaptor's WiFi network, but it can't find the mount on the network. So, I've two thoughts - either the new board doesn't work with the adaptor (but it does work with the handset?), or I've fried the adaptor at the same time as the main board, but I'm not sure if that's likely or even possible? Any thoughts on checking out the WiFi adaptor welcome. I think my options now are either a new adaptor at £54 and hope it works with the board, or a USB EQdirect cable at about £35, which is now an option as part of my wiring upgrade was adding a USB hub on the mount. I'm inclined to the latter even though it means more cables.
  21. So, I've come across the thread below, where a similar problem with a blown HEQ5 board is discussed. It mentions the dangers of dangling power cables or connecting/disconnecting cables without first switching off. In sorting out my cable routing, I've probably done just that - disconnected power cables and left them dangling as I re-routed them. So that's the probable source of the problem. Oh well, it's all a learning curve.
  22. The exact message was "Can't connect to M.C. Stand-Alone Mode". With the WiFi dongle it simply says "Can't Find Device." The Skywatcher manual says this message means the handset is not plugged in correctly, but I've checked it's in correctly, and neither handset nor dongle is talking to the mount. I'm a bit concerned that without knowing the cause, if I slot in a new/replacement board, that could go as well. Could just be old age though - I've had it 7 years and it was second hand when I bought it. Any advice on how to access the control board?
  23. Thanks for the suggestions - I previously powered it with a 12V mains adaptor. Tried that and no difference. I don't think it's the cable or handset as I can't connect via the WiFi dongle either, which suggests a mount side problem rather than the handset/cable.
  24. I've been adding a Pegasus Astrobox to my kit to power some dew heaters, and as that requires a 12V power supply, I bought a Leisure Battery to power it all. At first I connected my HEQ5 to one of the 12V outputs from the Pegasus but then thought there would be less cable stretch if I took 2 power lines from the battery one for the HEQ5 and one for the Pegasus. Set that up today, switched on - mount LED glows red. I then tried connecting my laptop to my Synscan WiFi - it connects to the WiFi OK, but said it couldn't find the device (I assume that means the HEQ5). At first I thought it might be to do with the WiFi connection, as yesterday I changed it from Access mode to Station mode, but then I tried the hand controller, and got a message that it couldn't connect to the MC (Motor Controller?) So now I'm thinking that the problem is the HEQ5 mount itself, and it's not talking to either handset or WiFi dongle. Maybe in setting up the new power supply I've switched off and on a few times too often and blown something, or maybe connecting to a new battery at about 12.8V was too much? A quick look and a replacement motherboard is about £120, so I'd like to be sure that's the problem before spending that much.
  25. Planets and nebula require two quite different approaches. Planets are very small but bright, so need a very long focal length to magnify them. As they are affected by atmospheric distortions, the usual technique is to record a video stream of hundreds of frames and use software to automatically select and stack the sharpest frames. Nebula are fairly large but dim, so require a short(ish) focal length and long exposures, which basically means a tracking mount. If you already have lenses at about 300mm, you might not need a telescope at first, just a tracking mount.
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